Arthropod Management Tests

Nault, Brian, A;Seaman,, Abby

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz081

Potato | Solanum tuberosum Colorado potato beetle | Leptinotarsa decemlineata Say pyrethrin, azadirachtin, Sabadilla alkaloids, Chromobacterium subtsugae, Bacillus thuringiensis, Bacillus galleriae These trials were conducted to evaluate insecticides allowed for organic production. The trials were conducted at the ACDS Research Inc. farm near North Rose, NY. In 2017, ‘B’ grade tubers of a late-season maturing, white-skinned potato cultivar, ‘Genesee’, were planted on 4 May. In 2018, ‘B’ grade tubers of a mid-season maturing, red-skinned potato cultivar, ‘Nordanna’, were planted on 11 May. Tubers were planted mechanically at a density of approximately 1 per foot. Plots included two 25-ft long rows flanked by a single unplanted row. Rows were 36 inches apart and plots were separated by a 5-ft alley of bare ground within rows. Weeds and diseases were managed following typical practices for this region. Other insect pests such as potato leafhopper, potato aphid, green peach aphid, and European corn borer were either absent or only observed at very low densities that did not damage the crop. Eight treatments including an untreated check were included in 2017, and seven were included in 2018 (Table 1). Treatments and an untreated check were arranged in a randomized complete block design with five replications. Table 1. Treatment . Active ingredient . 2017 Rate/A . 2018 Rate/A . Untreated check – – – Azera pyrethrin+azadirachtin 40 fl oz 40 fl oz Entrust SC spinosad 10 fl oz 3.5 and 7 fl oz Grandevo WDG Chromobacterium subtsugae 3 lbs 3 lbs V-10433 Sabadilla alkaloids 11 fl oz 11 fl oz BeetleGONE! B.t. galleriae Strain SDS 502 4 lbs Not tested Trident B.t. tenebrionis 3 and 6 qts 3 qts Treatment . Active ingredient . 2017 Rate/A . 2018 Rate/A . Untreated check – – – Azera pyrethrin+azadirachtin 40 fl oz 40 fl oz Entrust SC spinosad 10 fl oz 3.5 and 7 fl oz Grandevo WDG Chromobacterium subtsugae 3 lbs 3 lbs V-10433 Sabadilla alkaloids 11 fl oz 11 fl oz BeetleGONE! B.t. galleriae Strain SDS 502 4 lbs Not tested Trident B.t. tenebrionis 3 and 6 qts 3 qts Open in new tab Table 1. Treatment . Active ingredient . 2017 Rate/A . 2018 Rate/A . Untreated check – – – Azera pyrethrin+azadirachtin 40 fl oz 40 fl oz Entrust SC spinosad 10 fl oz 3.5 and 7 fl oz Grandevo WDG Chromobacterium subtsugae 3 lbs 3 lbs V-10433 Sabadilla alkaloids 11 fl oz 11 fl oz BeetleGONE! B.t. galleriae Strain SDS 502 4 lbs Not tested Trident B.t. tenebrionis 3 and 6 qts 3 qts Treatment . Active ingredient . 2017 Rate/A . 2018 Rate/A . Untreated check – – – Azera pyrethrin+azadirachtin 40 fl oz 40 fl oz Entrust SC spinosad 10 fl oz 3.5 and 7 fl oz Grandevo WDG Chromobacterium subtsugae 3 lbs 3 lbs V-10433 Sabadilla alkaloids 11 fl oz 11 fl oz BeetleGONE! B.t. galleriae Strain SDS 502 4 lbs Not tested Trident B.t. tenebrionis 3 and 6 qts 3 qts Open in new tab Foliar insecticide applications were made using a CO2-pressurized backpack sprayer and a boom equipped with four hollow-cone nozzles (Conejet TXVS-12) in which two nozzles each were directed over the canopy of single row (i.e., two rows were sprayed simultaneously with one pass of the spray rig). The sprayer was calibrated to deliver 31 gal of spray per acre at 40 psi. Insecticides were applied during the vegetative and early bloom stages to manage first-generation larvae. In 2017 treatments were applied on 15, 19, and 24 Jun with the exception of the 6 qt rate of Trident, which was sprayed on 19 and 26 Jun. In 2018 treatments were applied 15, 20, and 26 Jun. All applications were co-applied with NuFilm at 8 fl oz per acre. After first-generation adults started emerging in early July and when potatoes were in late bloom/early post bloom stages, in 2017 Coragen SC was applied at 5 fl oz/acre on 8 and 14 Jul and in 2018 a co-application of Coragen SC at 5 fl oz/acre + Radiant SC at 8 fl oz/acre + Induce at 0.125% v:v was applied on 14 Jul to all treatments to prevent first-generation adults from causing further damage (untreated plots were also treated). Efficacy of treatments was evaluated by recording the number of CPB life stages per plant during the first CPB generation. Numbers of egg masses (EM), adults (AD), small larvae (SL) (=1st and 2nd instars) and large larvae (LL) (=3rd and 4th instars) were recorded per plant from 10 randomly selected plants per plot. In 2017, for the 6 qt rate of Trident, data were taken on 26 Jun and 4 Jul, but are included in Table 2 under 23 and 29 Jun. For all other treatments and the untreated check, sampling dates included 19, 23, and 29 Jun. In 2018, sampling dates included 20 and 26 Jun and 4 Jul. Table 2. . . Mean numbers per plant . . . . . . . . . . . . . . Jun 19 . . . . Jun 23 . . . . Jun 29 . . . . Product Rate/A EM AD SL LL EM AD SL LL EM AD SL LL Untreated check 0.9 0.3 b 58 a 3.1 0.1 b 0.06 62 a 33 a 0 0 13 ab 46 a Azera 40 fl oz 1.1 0.7 ab 49 a 1.2 0.3 b 0.2 65 a 10 c 0 0 37 a 56 a Entrust SC 10 fl oz 1.9 1.8 a 3 b 0.1 0.9 a 0.3 1 c 0 d 0 0.1 1 c 1 b Grandevo WDG 3 lbs 1.3 1.1 ab 52 a 2.0 0.1 b 0.2 47 ab 29 abc 0 0 7 bc 39 a V-10433 11 fl oz 1.1 0.7 ab 52 a 2.4 0.1 b 0 64 a 27 ab 0 0 23 a 59 a BeetleGONE! 4 lbs 0.7 0.7 ab 67 a 2.5 0.1 b 0.1 71 a 31 ab 0 0 7 bc 31 a Trident (3 apps.) 3 qt 1.3 0.8 ab 57 a 3.5 0.2 b 0.1 51 ab 12 bc 0 0.1 15 ab 27 a Trident (2 apps.) 6 qt – – – – 0.0 b 0.2 33 b 18 abc 0 0 11 ab 46 a P value NS 0.0301 <0.0001 NS <0.0001 NS <0.0001 0.0001 NS NS <0.0001 <0.0001 . . Mean numbers per plant . . . . . . . . . . . . . . Jun 19 . . . . Jun 23 . . . . Jun 29 . . . . Product Rate/A EM AD SL LL EM AD SL LL EM AD SL LL Untreated check 0.9 0.3 b 58 a 3.1 0.1 b 0.06 62 a 33 a 0 0 13 ab 46 a Azera 40 fl oz 1.1 0.7 ab 49 a 1.2 0.3 b 0.2 65 a 10 c 0 0 37 a 56 a Entrust SC 10 fl oz 1.9 1.8 a 3 b 0.1 0.9 a 0.3 1 c 0 d 0 0.1 1 c 1 b Grandevo WDG 3 lbs 1.3 1.1 ab 52 a 2.0 0.1 b 0.2 47 ab 29 abc 0 0 7 bc 39 a V-10433 11 fl oz 1.1 0.7 ab 52 a 2.4 0.1 b 0 64 a 27 ab 0 0 23 a 59 a BeetleGONE! 4 lbs 0.7 0.7 ab 67 a 2.5 0.1 b 0.1 71 a 31 ab 0 0 7 bc 31 a Trident (3 apps.) 3 qt 1.3 0.8 ab 57 a 3.5 0.2 b 0.1 51 ab 12 bc 0 0.1 15 ab 27 a Trident (2 apps.) 6 qt – – – – 0.0 b 0.2 33 b 18 abc 0 0 11 ab 46 a P value NS 0.0301 <0.0001 NS <0.0001 NS <0.0001 0.0001 NS NS <0.0001 <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS = not significant). Open in new tab Table 2. . . Mean numbers per plant . . . . . . . . . . . . . . Jun 19 . . . . Jun 23 . . . . Jun 29 . . . . Product Rate/A EM AD SL LL EM AD SL LL EM AD SL LL Untreated check 0.9 0.3 b 58 a 3.1 0.1 b 0.06 62 a 33 a 0 0 13 ab 46 a Azera 40 fl oz 1.1 0.7 ab 49 a 1.2 0.3 b 0.2 65 a 10 c 0 0 37 a 56 a Entrust SC 10 fl oz 1.9 1.8 a 3 b 0.1 0.9 a 0.3 1 c 0 d 0 0.1 1 c 1 b Grandevo WDG 3 lbs 1.3 1.1 ab 52 a 2.0 0.1 b 0.2 47 ab 29 abc 0 0 7 bc 39 a V-10433 11 fl oz 1.1 0.7 ab 52 a 2.4 0.1 b 0 64 a 27 ab 0 0 23 a 59 a BeetleGONE! 4 lbs 0.7 0.7 ab 67 a 2.5 0.1 b 0.1 71 a 31 ab 0 0 7 bc 31 a Trident (3 apps.) 3 qt 1.3 0.8 ab 57 a 3.5 0.2 b 0.1 51 ab 12 bc 0 0.1 15 ab 27 a Trident (2 apps.) 6 qt – – – – 0.0 b 0.2 33 b 18 abc 0 0 11 ab 46 a P value NS 0.0301 <0.0001 NS <0.0001 NS <0.0001 0.0001 NS NS <0.0001 <0.0001 . . Mean numbers per plant . . . . . . . . . . . . . . Jun 19 . . . . Jun 23 . . . . Jun 29 . . . . Product Rate/A EM AD SL LL EM AD SL LL EM AD SL LL Untreated check 0.9 0.3 b 58 a 3.1 0.1 b 0.06 62 a 33 a 0 0 13 ab 46 a Azera 40 fl oz 1.1 0.7 ab 49 a 1.2 0.3 b 0.2 65 a 10 c 0 0 37 a 56 a Entrust SC 10 fl oz 1.9 1.8 a 3 b 0.1 0.9 a 0.3 1 c 0 d 0 0.1 1 c 1 b Grandevo WDG 3 lbs 1.3 1.1 ab 52 a 2.0 0.1 b 0.2 47 ab 29 abc 0 0 7 bc 39 a V-10433 11 fl oz 1.1 0.7 ab 52 a 2.4 0.1 b 0 64 a 27 ab 0 0 23 a 59 a BeetleGONE! 4 lbs 0.7 0.7 ab 67 a 2.5 0.1 b 0.1 71 a 31 ab 0 0 7 bc 31 a Trident (3 apps.) 3 qt 1.3 0.8 ab 57 a 3.5 0.2 b 0.1 51 ab 12 bc 0 0.1 15 ab 27 a Trident (2 apps.) 6 qt – – – – 0.0 b 0.2 33 b 18 abc 0 0 11 ab 46 a P value NS 0.0301 <0.0001 NS <0.0001 NS <0.0001 0.0001 NS NS <0.0001 <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS = not significant). Open in new tab Visual estimates of defoliation were made on 26 Jun and 3 Jul in 2017 and on 26 Jun and 4 Jul in 2018. Defoliation estimates for each plot were based on the following 14-point scale (0%, 0–3%, 3–9%, 9–17%, 17–27%, 27–38%, 38–50%, 50–62%, 62–73%, 73–82%, 82–93%, 93–97%, 97–100%, and 100%). The midpoint of each estimate was used in the statistical analyses. On 24 Aug (both years), the left-hand row in each plot was harvested and the numbers of Grade ‘A’ (>1.5 inches in diam.) and Grade ‘B’ (<1.5 in diam.) tubers were weighed. All data were analyzed using a mixed linear model procedure of SAS (PROC MIXED) in which treatment was considered fixed and replication as random in the model. All pairwise comparisons between means were made using Tukey’s Studentized Range (HSD) Test at P < 0.05. Insect count data and tuber yield data were transformed with a log10 (x + 1) function to stabilize variance. Defoliation rating data were transformed with a square root (x + 0.001) function to stabilize variance. In 2017, CPB pressure was high. Conditions were moderate and wet from early May through late June. A moderate rainfall event occurred less than 30 min after the first application, whereas other rainfall events generally occurred within a day or so after the other applications. On 15 Jun, before treatments were applied, densities of EM, AD, SL, and LL per plant were 2.0, 0.4, 0.7, and 0.02, respectively. The action threshold recommended in NY for biologically based products is 1.5 SL per plant, 0.6 LL per plant and evidence that 25% of EM are hatching. While larval densities were below threshold, over 25% of the EM were hatching, so a decision was made to initiate applications. On 19 Jun (4 d after the first application for all treatments except Trident at 6 qt/A), there were more AD and EM in plots treated with Entrust than in the untreated check; densities of AD and EM in the other treatments were intermediate between the untreated check and Entrust treatment (Table 2). More AD and EM in the Entrust treatment compared with the untreated check was likely an anomaly rather than a consequence of Entrust on the population. An alternative explanation was that plants in the Entrust treatment were more attractive to colonizing AD than the other treatments because they had fewer CPB and slightly less feeding injury (injury was less than 5% among all treatments). Entrust was the only product that significantly reduced the numbers of SL compared with those in the untreated check (Table 2). These results indicated that despite the moderate rainfall event that occurred soon after the plots were treated, Entrust worked extremely well. There were too few LL at this point in the season to observe an impact of the various insecticide treatments. On 23 Jun, there continued to be more AD and EM in the Entrust treatment compared with the untreated check and other insecticide treatments (Table 2). However, Entrust was significantly better in controlling the larval population (both SL and LL) compared with all other insecticide treatments (Table 2). The high rate of Trident also significantly reduced densities of SL compared with the untreated check, whereas the low rate of Trident and Azera significantly reduced densities of LL compared with the untreated check (Table 2). On 29 Jun, only Entrust significantly reduced the larval population compared with the other treatments (Table 2). Overall, season mean total numbers of ADs and EMs in the Entrust treatment were greater than those in the untreated check, but SL and LL densities were significantly lower than in the untreated control and all other insecticide treatments (Table 3). CPB defoliation levels provided a better indication of insecticide performance than CPB densities. On 26 Jun, all treatments except Grandevo and BeetleGONE significantly reduced defoliation levels compared with those in the untreated check (Table 3). The lowest level of defoliation was observed in the Entrust treatment, followed by both Trident treatments, Azera and V-10433. On 3 Jul, all treatments except Grandevo, BeetleGONE, and V-10433 significantly reduced defoliation levels compared with those in the untreated check (Table 3). The lowest level of defoliation was observed in the Entrust treatment, followed by both Trident treatments and Azera. Table 3. Product . Rate/A . Season mean total numbers per plant . . . . Mean % defoliation . . . . EM . AD . SL . LL . 26 Jun . 3 Jul . Untreated check 1.0 b 0.4 b 133 a 82 a 69 a 100 a Azera 40 fl oz 1.4 ab 0.9 ab 151 a 67 a 16 c 31 b Entrust SC 10 fl oz 2.8 a 2.2 a 5 b 1 b 0 d 1 c Grandevo WDG 3 lbs 1.4 ab 1.2 ab 107 a 69 a 71 a 98 a V-10433 11 fl oz 1.2 ab 0.7 ab 139 a 88 a 38 b 98 a BeetleGONE! 4 lbs 0.7 b 0.8 ab 145 a 65 a 81 a 100 a Trident (low rate x 3 apps.) 3 qt 1.5 ab 1.0 ab 123 a 43 a 11 c 16 b Trident (high rate x 2 apps.) 6 qt – – – – 8 c 36 b P value 0.0243 0.0094 <0.0001 <0.0001 <0.0001 <0.0001 Product . Rate/A . Season mean total numbers per plant . . . . Mean % defoliation . . . . EM . AD . SL . LL . 26 Jun . 3 Jul . Untreated check 1.0 b 0.4 b 133 a 82 a 69 a 100 a Azera 40 fl oz 1.4 ab 0.9 ab 151 a 67 a 16 c 31 b Entrust SC 10 fl oz 2.8 a 2.2 a 5 b 1 b 0 d 1 c Grandevo WDG 3 lbs 1.4 ab 1.2 ab 107 a 69 a 71 a 98 a V-10433 11 fl oz 1.2 ab 0.7 ab 139 a 88 a 38 b 98 a BeetleGONE! 4 lbs 0.7 b 0.8 ab 145 a 65 a 81 a 100 a Trident (low rate x 3 apps.) 3 qt 1.5 ab 1.0 ab 123 a 43 a 11 c 16 b Trident (high rate x 2 apps.) 6 qt – – – – 8 c 36 b P value 0.0243 0.0094 <0.0001 <0.0001 <0.0001 <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS= not significant). Open in new tab Table 3. Product . Rate/A . Season mean total numbers per plant . . . . Mean % defoliation . . . . EM . AD . SL . LL . 26 Jun . 3 Jul . Untreated check 1.0 b 0.4 b 133 a 82 a 69 a 100 a Azera 40 fl oz 1.4 ab 0.9 ab 151 a 67 a 16 c 31 b Entrust SC 10 fl oz 2.8 a 2.2 a 5 b 1 b 0 d 1 c Grandevo WDG 3 lbs 1.4 ab 1.2 ab 107 a 69 a 71 a 98 a V-10433 11 fl oz 1.2 ab 0.7 ab 139 a 88 a 38 b 98 a BeetleGONE! 4 lbs 0.7 b 0.8 ab 145 a 65 a 81 a 100 a Trident (low rate x 3 apps.) 3 qt 1.5 ab 1.0 ab 123 a 43 a 11 c 16 b Trident (high rate x 2 apps.) 6 qt – – – – 8 c 36 b P value 0.0243 0.0094 <0.0001 <0.0001 <0.0001 <0.0001 Product . Rate/A . Season mean total numbers per plant . . . . Mean % defoliation . . . . EM . AD . SL . LL . 26 Jun . 3 Jul . Untreated check 1.0 b 0.4 b 133 a 82 a 69 a 100 a Azera 40 fl oz 1.4 ab 0.9 ab 151 a 67 a 16 c 31 b Entrust SC 10 fl oz 2.8 a 2.2 a 5 b 1 b 0 d 1 c Grandevo WDG 3 lbs 1.4 ab 1.2 ab 107 a 69 a 71 a 98 a V-10433 11 fl oz 1.2 ab 0.7 ab 139 a 88 a 38 b 98 a BeetleGONE! 4 lbs 0.7 b 0.8 ab 145 a 65 a 81 a 100 a Trident (low rate x 3 apps.) 3 qt 1.5 ab 1.0 ab 123 a 43 a 11 c 16 b Trident (high rate x 2 apps.) 6 qt – – – – 8 c 36 b P value 0.0243 0.0094 <0.0001 <0.0001 <0.0001 <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS= not significant). Open in new tab In 2018, weather conditions were hot and dry in June and July and hot with moderate rainfall in August. CPB pressure was very high. On 15 Jun, immediately before treatments were applied, densities of EM, AD, SL, and LL per plant were 2.3, 1.3, 5.3, and 0.1, respectively. Action thresholds were mentioned previously; the threshold was exceeded for small larvae, so the trial was initiated. On 20 Jun (5 d after the first application), densities of LL in both Entrust treatments and Trident were significantly lower than those in the untreated check (Table 4). Densities of LL were similar between the Entrust treatments and both were significantly lower than those in Trident. Densities of SL and LL in Azera, Grandevo, and V-10433 were similar to those in the untreated check (Table 4). There were fewer SL in the high rate of Entrust compared with all other treatments and the untreated check, but not all of these differences were statistically significant. Densities of ADs and EMs were low and similar among all treated and untreated plots (Table 4). Table 4. Product . Rate/A . Mean numbers per plant . . . . . . . . . . . . . . Jun 20 . . . . Jun 26 . . . . Jul 4 . . . . . . EM . AD . SL . LL . EM . AD . SL . LL . EM . AD . SL . LL . Untreated check – 0.8 0.2 12 ab 36 a 0.1 0 8 48 0 0 0 37 a Azera 40 oz 0.6 0.1 17 a 21 a 0.1 0 8 44 a 0 0 0 48 a Entrust SC (low) 3.5 oz 0.8 0.2 13 ab 1 c 0.4 0.2 2 1 c 0.1 0.1 0 7 b Entrust SC (high) 7 oz 0.8 0.2 5 b 1 c 0.2 0.1 0 0 c 0.1 0 0 3 c Grandevo WDG 3 lb 0.9 0.1 17 ab 30 a 0.1 0 5 59 a 0 0 0 32 a V-10433 11 fl oz 0.6 0.1 15 a 24 a 0.1 0 7 50 a 0 0 0 40 a Trident 3 qt 0.5 0.3 16 a 7 b 0 0.1 7 19 b 0 0 0 42 a P value NS NS 0.0125 <0.0001 NS NS <0.0001 <0.0001 NS NS NS <0.0001 Product . Rate/A . Mean numbers per plant . . . . . . . . . . . . . . Jun 20 . . . . Jun 26 . . . . Jul 4 . . . . . . EM . AD . SL . LL . EM . AD . SL . LL . EM . AD . SL . LL . Untreated check – 0.8 0.2 12 ab 36 a 0.1 0 8 48 0 0 0 37 a Azera 40 oz 0.6 0.1 17 a 21 a 0.1 0 8 44 a 0 0 0 48 a Entrust SC (low) 3.5 oz 0.8 0.2 13 ab 1 c 0.4 0.2 2 1 c 0.1 0.1 0 7 b Entrust SC (high) 7 oz 0.8 0.2 5 b 1 c 0.2 0.1 0 0 c 0.1 0 0 3 c Grandevo WDG 3 lb 0.9 0.1 17 ab 30 a 0.1 0 5 59 a 0 0 0 32 a V-10433 11 fl oz 0.6 0.1 15 a 24 a 0.1 0 7 50 a 0 0 0 40 a Trident 3 qt 0.5 0.3 16 a 7 b 0 0.1 7 19 b 0 0 0 42 a P value NS NS 0.0125 <0.0001 NS NS <0.0001 <0.0001 NS NS NS <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS= not significant). Open in new tab Table 4. Product . Rate/A . Mean numbers per plant . . . . . . . . . . . . . . Jun 20 . . . . Jun 26 . . . . Jul 4 . . . . . . EM . AD . SL . LL . EM . AD . SL . LL . EM . AD . SL . LL . Untreated check – 0.8 0.2 12 ab 36 a 0.1 0 8 48 0 0 0 37 a Azera 40 oz 0.6 0.1 17 a 21 a 0.1 0 8 44 a 0 0 0 48 a Entrust SC (low) 3.5 oz 0.8 0.2 13 ab 1 c 0.4 0.2 2 1 c 0.1 0.1 0 7 b Entrust SC (high) 7 oz 0.8 0.2 5 b 1 c 0.2 0.1 0 0 c 0.1 0 0 3 c Grandevo WDG 3 lb 0.9 0.1 17 ab 30 a 0.1 0 5 59 a 0 0 0 32 a V-10433 11 fl oz 0.6 0.1 15 a 24 a 0.1 0 7 50 a 0 0 0 40 a Trident 3 qt 0.5 0.3 16 a 7 b 0 0.1 7 19 b 0 0 0 42 a P value NS NS 0.0125 <0.0001 NS NS <0.0001 <0.0001 NS NS NS <0.0001 Product . Rate/A . Mean numbers per plant . . . . . . . . . . . . . . Jun 20 . . . . Jun 26 . . . . Jul 4 . . . . . . EM . AD . SL . LL . EM . AD . SL . LL . EM . AD . SL . LL . Untreated check – 0.8 0.2 12 ab 36 a 0.1 0 8 48 0 0 0 37 a Azera 40 oz 0.6 0.1 17 a 21 a 0.1 0 8 44 a 0 0 0 48 a Entrust SC (low) 3.5 oz 0.8 0.2 13 ab 1 c 0.4 0.2 2 1 c 0.1 0.1 0 7 b Entrust SC (high) 7 oz 0.8 0.2 5 b 1 c 0.2 0.1 0 0 c 0.1 0 0 3 c Grandevo WDG 3 lb 0.9 0.1 17 ab 30 a 0.1 0 5 59 a 0 0 0 32 a V-10433 11 fl oz 0.6 0.1 15 a 24 a 0.1 0 7 50 a 0 0 0 40 a Trident 3 qt 0.5 0.3 16 a 7 b 0 0.1 7 19 b 0 0 0 42 a P value NS NS 0.0125 <0.0001 NS NS <0.0001 <0.0001 NS NS NS <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS= not significant). Open in new tab On 26 Jun (6 d after the second application), results were similar to those on 20 Jun (Table 4). Densities of LL in both Entrust treatments and Trident were significantly lower than those in the untreated check and the other treatments. Densities of SL and LL in both Entrust treatments were significantly lower than those in Trident. Densities of ADs and EMs were similar among all treated and untreated plots (Table 4). On 4 Jul (8 d after the third application), only Entrust significantly reduced the numbers of LL compared with those in the untreated check and the other treatments (Table 4). Densities of LL in the high rate of Entrust were significantly lower than those in the low rate of Entrust. Densities of ADs, EMs, and SL were very low and similar among all treated and untreated plots (Table 4). Overall, the high rate of Entrust had the fewest numbers of SL and LL compared with all other treatments (Table 5). The low rate of Entrust, which had the second lowest numbers of LL, also performed well (Table 5). Although LL densities in Trident did not differ significantly from the untreated check, densities were reduced by almost 50% compared with those in the untreated check. None of the other treatments affected larval populations. CPB defoliation levels tended to positively correlate with the CPB densities. On 26 Jun, Entrust, Trident, and Azera had either no defoliation or very low levels of defoliation compared with those in the untreated check and the other treatments (Table 5). On 4 Jul, which was near the end of the first generation, the lowest level of defoliation was observed in both Entrust treatments, followed by Trident and Azera. Table 5. Product . Rate/A . Mean total numbers per plant . . . . Mean % Defoliation . . . . EM . AD . SL . LL . Jun 26 . Jul 4 . Untreated check – 0.8 0.2 20 a 121 a 21 a 78 a Azera 40 oz 0.7 0.2 25 a 113 a 3 b 21 b Entrust SC 3.5 oz 1.3 0.4 15 a 9 b 0 b 1 c Entrust SC 7 oz 1.1 0.4 5 b 3 c 0 b 0 c Grandevo WDG 3 lb 1.0 0.1 22 a 121 a 21 a 80 a V-10433 11 fl oz 0.7 0.1 22 a 114 a 14 a 79 a Trident 3 qt 0.6 0.4 23 a 68 a 1 b 15 b P Value NS NS 0.0002 <0.0001 <0.0001 <0.0001 Product . Rate/A . Mean total numbers per plant . . . . Mean % Defoliation . . . . EM . AD . SL . LL . Jun 26 . Jul 4 . Untreated check – 0.8 0.2 20 a 121 a 21 a 78 a Azera 40 oz 0.7 0.2 25 a 113 a 3 b 21 b Entrust SC 3.5 oz 1.3 0.4 15 a 9 b 0 b 1 c Entrust SC 7 oz 1.1 0.4 5 b 3 c 0 b 0 c Grandevo WDG 3 lb 1.0 0.1 22 a 121 a 21 a 80 a V-10433 11 fl oz 0.7 0.1 22 a 114 a 14 a 79 a Trident 3 qt 0.6 0.4 23 a 68 a 1 b 15 b P Value NS NS 0.0002 <0.0001 <0.0001 <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS = not significant). Open in new tab Table 5. Product . Rate/A . Mean total numbers per plant . . . . Mean % Defoliation . . . . EM . AD . SL . LL . Jun 26 . Jul 4 . Untreated check – 0.8 0.2 20 a 121 a 21 a 78 a Azera 40 oz 0.7 0.2 25 a 113 a 3 b 21 b Entrust SC 3.5 oz 1.3 0.4 15 a 9 b 0 b 1 c Entrust SC 7 oz 1.1 0.4 5 b 3 c 0 b 0 c Grandevo WDG 3 lb 1.0 0.1 22 a 121 a 21 a 80 a V-10433 11 fl oz 0.7 0.1 22 a 114 a 14 a 79 a Trident 3 qt 0.6 0.4 23 a 68 a 1 b 15 b P Value NS NS 0.0002 <0.0001 <0.0001 <0.0001 Product . Rate/A . Mean total numbers per plant . . . . Mean % Defoliation . . . . EM . AD . SL . LL . Jun 26 . Jul 4 . Untreated check – 0.8 0.2 20 a 121 a 21 a 78 a Azera 40 oz 0.7 0.2 25 a 113 a 3 b 21 b Entrust SC 3.5 oz 1.3 0.4 15 a 9 b 0 b 1 c Entrust SC 7 oz 1.1 0.4 5 b 3 c 0 b 0 c Grandevo WDG 3 lb 1.0 0.1 22 a 121 a 21 a 80 a V-10433 11 fl oz 0.7 0.1 22 a 114 a 14 a 79 a Trident 3 qt 0.6 0.4 23 a 68 a 1 b 15 b P Value NS NS 0.0002 <0.0001 <0.0001 <0.0001 Means followed by the same letter within column are not significantly different (P > 0.05; Tukey’s Studentized Range [HSD] Test; n = 5; NS = not significant). Open in new tab This research was supported by industry gifts of pesticides and by the USDA National Institute of Food and Agriculture, Hatch project 1011209. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the National Institute of Food and Agriculture (NIFA) or the United States Department of Agriculture (USDA). © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Buntin, G, David;All, John, N

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz052

Sorghum (broom, durra, Guinea corn, jowar) | Sorghum bicolor Lesser Cornstalk borer (LCSB) | Elasmopalpus lignosellus (Zeller) chlorpyrifos, clothianidin, imidacloprid, lambda-cyhalothrin, thiamethoxam Lesser cornstalk borer (LCSB) is a seedling pest of sorghum and can cause severe plant injury and stand loss under hot, dry conditions with conventional tillage. Two trials evaluating soil-applied and seed-applied insecticides were conducted at the University of Georgia Southeast Research and Education Center (32.8750, −82.2146) located near Midville, GA. Sorghum was planted in Trial 1 on 10 Jul and Trial 2 on 11 Sep. Each trial was arranged in an RCB design with 5 replications. Plots were 2 rows by 20 ft long. Seed was planted with a 2-row cone planter in 36 inch rows at the rate of 100,000 seeds per acre. Seed treatments were applied to seed by the manufacturer and included a base fungicide seed treatment from each manufacturer. All seed was treated with Concep III for use of Dual Magnum (S-metolachlor) herbicide (Syngenta Crop Protection, Greensboro, NC) at planting. Lorsban 15G treatments were applied at planting as a 7-inch band and lightly incorporated. Liquid insecticides were applied immediately after planting of seed as a broadcast spray using a CO2-powered backpack sprayer using TeeJet 8002 flat-fan nozzles applying 25 gpa at 40 psi. Stand counts and number of damaged (dead and dying with dead-heart symptoms) plants were measured in the entire plot at 15 and 23 days after planting (DAP) in Trial 1 and at 14 DAP in Trial 2. Untreated plants in border rows were inspected to confirm damage was by LCSB. Yield of Trial 1 was measured by hand harvesting all viable panicles in a 10-ft section of row and threshing panicles with a small bundle thresher. Grain weight, test weight, and moisture content were measured and grain yield calculated and adjusted to 14% moisture content. Grain yield was not measured in Trial 2. In Trial 1, rainfall total of 2.34 inch fell on days 2–4 after planting with no additional rainfall before the second stand count and rating. In Trial 2, 0.84 inch of rain fell from planting to 14 DAP. Data were analyzed using generalized linear mixed model analyses (PROC MIXED, SAS Institute 2008) with treatment modeled as a fixed effect and replication modeled as a random effect. Percentage data were arcsine-square root transformed before analysis. When analyses suggested differences among treatments (α = 0.05), treatments were separated using the LS means separated PLM option in SAS. LCSB reduced plant stands and cause extensive seedling damage in both trials. No other insect pest was present at damaging levels and sugarcane aphid was not present in 2012. In Trial 1, plant stands were significantly different among treatments, but stands with insecticide treatments usually were not different when compared with base fungicide only treatment (Table 1). Seed treatment with clothianidin (NipsIt Inside, Poncho 600) alone or with Lorsban 15G, Lorsban 4E or Karate Z had greater plant numbers than the bare seed check at 23 DAP. Plant numbers in Cruiser 5FS treatments at 23 DAP were not greater than the bare seed check and in most comparisons had fewer plants than the clothianidin seed treatments. The clothianidin treatments alone or with Lorsban 15G, Lorsban 4E, and Karate Z also had a lower percentage of damaged plants than the comparable base fungicide or bare seed treatments. Cruiser 5FS treatments had similar percentages of damaged plants as the base fungicide and bare seed treatments. The only treatment that yielded more than the bare seed treatment in Trial 1 was the NipsIt Inside treatment. No other treatment yielded significantly more than the bare seed treatment, including the other treatments with clothianidin on the seed. In Trial 2, LSCB borer infestation was severe with almost 90% of plants with damage in the bare seed check (Table 2). All insecticide seed treatments and Lorsban 15G without a seed treatment had greater plant numbers than the bare seed check and the Bayer and Valent base fungicide treatments. The percent of damaged plants was large in all treatments. All three seed treatments and NipsIt Inside + Lorsban 15G treatment had significantly fewer damaged plants than the bare seed check. The seed treatments with clothianidin (Poncho 600, NipsIt Inside) reduced seedling damage by LSCB. Cruiser 5FS seed treatments were not effective in Trial 1 but did partly reduce damage in Trial 2. However, at the severe level of damage in these trials, no treatment was highly effective in preventing LCSB seedling damage. No phytotoxicity was observed. Table 1. Trial 1 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Grain yield bu/acre 15 DAP (24 Jul) 23 DAP (2 Aug) 15 DAP (24 Jul) 23 DAP (2 Aug) Untreated bare seed – 151.2bcd 135.6de 38.1bc 46.0ab 35.3bc Bayer base fungicide treatment – 165.8abc 155.4ab 34.8bc 47.4ab 37.4bc Poncho 600 + Bayer fungicides 6.4 fl oz/cwt 167.8ab 159.6a 12.9d 29.5de 42.4ab Valent base fungicide treatment – 145.4cd 138.8cd 49.1ab 52.7a 25.8c NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 169.4ab 149.8a-d 13.0d 25.4e 51.8a Syngenta base fungicide treatment – 147.2cd 121.2e 50.3a 38.2bcd 30.8bc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 139.6d 135.0de 43.3abc 47.7ab 26.7c Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 149.2cd 140.0bcd 35.9c 44.9ab 35.5bc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 171.0ab 159.4a 10.4d 31.7cde 44.1ab NipsIt Inside + Lorsban 4E - broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 170.2ab 152.6abc 12.3d 31.9cde 38.7abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 175.6a 164.8a 13.9d 37.5b-e 42.4ab Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 156.0bcd 135.6de 33.1c 41.8abc 34.4bc P > F 0.0001 0.0001 0.0030 0.0004 0.0269 CV 7.93 8.66 28.04 24.21 29.8 Trial 1 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Grain yield bu/acre 15 DAP (24 Jul) 23 DAP (2 Aug) 15 DAP (24 Jul) 23 DAP (2 Aug) Untreated bare seed – 151.2bcd 135.6de 38.1bc 46.0ab 35.3bc Bayer base fungicide treatment – 165.8abc 155.4ab 34.8bc 47.4ab 37.4bc Poncho 600 + Bayer fungicides 6.4 fl oz/cwt 167.8ab 159.6a 12.9d 29.5de 42.4ab Valent base fungicide treatment – 145.4cd 138.8cd 49.1ab 52.7a 25.8c NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 169.4ab 149.8a-d 13.0d 25.4e 51.8a Syngenta base fungicide treatment – 147.2cd 121.2e 50.3a 38.2bcd 30.8bc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 139.6d 135.0de 43.3abc 47.7ab 26.7c Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 149.2cd 140.0bcd 35.9c 44.9ab 35.5bc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 171.0ab 159.4a 10.4d 31.7cde 44.1ab NipsIt Inside + Lorsban 4E - broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 170.2ab 152.6abc 12.3d 31.9cde 38.7abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 175.6a 164.8a 13.9d 37.5b-e 42.4ab Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 156.0bcd 135.6de 33.1c 41.8abc 34.4bc P > F 0.0001 0.0001 0.0030 0.0004 0.0269 CV 7.93 8.66 28.04 24.21 29.8 Column LS means followed by the same letter are not significantly different (PROC MIXED, protected T-groupings, α = 0.05). acwt = 100 lb of seed. b0.5 lb AI per acre. c0.03 lb AI per acre. Open in new tab Table 1. Trial 1 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Grain yield bu/acre 15 DAP (24 Jul) 23 DAP (2 Aug) 15 DAP (24 Jul) 23 DAP (2 Aug) Untreated bare seed – 151.2bcd 135.6de 38.1bc 46.0ab 35.3bc Bayer base fungicide treatment – 165.8abc 155.4ab 34.8bc 47.4ab 37.4bc Poncho 600 + Bayer fungicides 6.4 fl oz/cwt 167.8ab 159.6a 12.9d 29.5de 42.4ab Valent base fungicide treatment – 145.4cd 138.8cd 49.1ab 52.7a 25.8c NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 169.4ab 149.8a-d 13.0d 25.4e 51.8a Syngenta base fungicide treatment – 147.2cd 121.2e 50.3a 38.2bcd 30.8bc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 139.6d 135.0de 43.3abc 47.7ab 26.7c Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 149.2cd 140.0bcd 35.9c 44.9ab 35.5bc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 171.0ab 159.4a 10.4d 31.7cde 44.1ab NipsIt Inside + Lorsban 4E - broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 170.2ab 152.6abc 12.3d 31.9cde 38.7abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 175.6a 164.8a 13.9d 37.5b-e 42.4ab Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 156.0bcd 135.6de 33.1c 41.8abc 34.4bc P > F 0.0001 0.0001 0.0030 0.0004 0.0269 CV 7.93 8.66 28.04 24.21 29.8 Trial 1 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Grain yield bu/acre 15 DAP (24 Jul) 23 DAP (2 Aug) 15 DAP (24 Jul) 23 DAP (2 Aug) Untreated bare seed – 151.2bcd 135.6de 38.1bc 46.0ab 35.3bc Bayer base fungicide treatment – 165.8abc 155.4ab 34.8bc 47.4ab 37.4bc Poncho 600 + Bayer fungicides 6.4 fl oz/cwt 167.8ab 159.6a 12.9d 29.5de 42.4ab Valent base fungicide treatment – 145.4cd 138.8cd 49.1ab 52.7a 25.8c NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 169.4ab 149.8a-d 13.0d 25.4e 51.8a Syngenta base fungicide treatment – 147.2cd 121.2e 50.3a 38.2bcd 30.8bc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 139.6d 135.0de 43.3abc 47.7ab 26.7c Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 149.2cd 140.0bcd 35.9c 44.9ab 35.5bc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 171.0ab 159.4a 10.4d 31.7cde 44.1ab NipsIt Inside + Lorsban 4E - broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 170.2ab 152.6abc 12.3d 31.9cde 38.7abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 175.6a 164.8a 13.9d 37.5b-e 42.4ab Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 156.0bcd 135.6de 33.1c 41.8abc 34.4bc P > F 0.0001 0.0001 0.0030 0.0004 0.0269 CV 7.93 8.66 28.04 24.21 29.8 Column LS means followed by the same letter are not significantly different (PROC MIXED, protected T-groupings, α = 0.05). acwt = 100 lb of seed. b0.5 lb AI per acre. c0.03 lb AI per acre. Open in new tab Table 2. Trial 2 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Untreated bare seed – 84.8e 88.7a Bayer base fungicide treatment – 90.2de 83.2ab Bayer fungicides + Poncho 600 6.4 fl oz/cwt 144.8ab 66.4bcd Valent base fungicide treatment – 80.0e 79.4ab NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 132.8abc 57.6cd Syngenta base fungicide treatment – 117.0bcd 76.7abc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 131.6abc 53.2d Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 107.4cde 76.5abc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 153.4a 70.6bcd NipsIt Inside + Lorsban 4E – broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 137.6ab 75.1abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 138.4ab 73.0abcd Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 127.2abc 79.2abc P > F 0.0001 0.0351 CV 19.38 21.05 Trial 2 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Untreated bare seed – 84.8e 88.7a Bayer base fungicide treatment – 90.2de 83.2ab Bayer fungicides + Poncho 600 6.4 fl oz/cwt 144.8ab 66.4bcd Valent base fungicide treatment – 80.0e 79.4ab NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 132.8abc 57.6cd Syngenta base fungicide treatment – 117.0bcd 76.7abc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 131.6abc 53.2d Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 107.4cde 76.5abc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 153.4a 70.6bcd NipsIt Inside + Lorsban 4E – broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 137.6ab 75.1abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 138.4ab 73.0abcd Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 127.2abc 79.2abc P > F 0.0001 0.0351 CV 19.38 21.05 Column LS means followed by the same letter are not significantly different (PROC MIXED, protected T-groupings, α = 0.05). acwt = 100 lb of seed. b0.5 lb AI per acre. c0.03 lb AI per acre. Open in new tab Table 2. Trial 2 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Untreated bare seed – 84.8e 88.7a Bayer base fungicide treatment – 90.2de 83.2ab Bayer fungicides + Poncho 600 6.4 fl oz/cwt 144.8ab 66.4bcd Valent base fungicide treatment – 80.0e 79.4ab NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 132.8abc 57.6cd Syngenta base fungicide treatment – 117.0bcd 76.7abc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 131.6abc 53.2d Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 107.4cde 76.5abc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 153.4a 70.6bcd NipsIt Inside + Lorsban 4E – broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 137.6ab 75.1abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 138.4ab 73.0abcd Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 127.2abc 79.2abc P > F 0.0001 0.0351 CV 19.38 21.05 Trial 2 Treatment/formulation Rate Amt/cwta or acre Total plants per 40 ft row Damaged plants (%) Untreated bare seed – 84.8e 88.7a Bayer base fungicide treatment – 90.2de 83.2ab Bayer fungicides + Poncho 600 6.4 fl oz/cwt 144.8ab 66.4bcd Valent base fungicide treatment – 80.0e 79.4ab NipsIt Inside + Valent fungicides 6.4 fl oz/cwt 132.8abc 57.6cd Syngenta base fungicide treatment – 117.0bcd 76.7abc Cruiser 5FS + Syngenta fungicides 5.1 fl oz/cwt 131.6abc 53.2d Valent base fungicides + Lorsban 15G as a band 3.4 lb/acreb 107.4cde 76.5abc NipsIt Inside + Lorsban 15G as a band 6.4 fl oz/cwt 3.4 lb/acreb 153.4a 70.6bcd NipsIt Inside + Lorsban 4E – broadcast spray 6.4 fl oz/cwt 3.4 lb/acreb 137.6ab 75.1abc NipsIt Inside + Karate Z (2.08) – broadcast spray 6.4 fl oz/cwt 1.92 fl oz/acrec 138.4ab 73.0abcd Cruiser 5FS + Karate Z (2.08) – broadcast spray 5.1 fl oz/cwt 1.92 fl oz/acrec 127.2abc 79.2abc P > F 0.0001 0.0351 CV 19.38 21.05 Column LS means followed by the same letter are not significantly different (PROC MIXED, protected T-groupings, α = 0.05). acwt = 100 lb of seed. b0.5 lb AI per acre. c0.03 lb AI per acre. Open in new tab This research was supported in part by industry gifts. © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Schmidt-Jeffris, Rebecca, A;Coffey,, John

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz073

Bean | Phaseolus spp Twospotted spider mite (TSSM) | Tetranychus urticae Koch propylene glycol, fenpyroximate The objective of this test was to determine the efficacy of Acaritouch for control of TSSM on lima bean, either alone or in combination with Portal XLO and applied one or two times. The experiments were conducted in a propagation room in Charleston, SC. Lima bean var. ‘Henderson Bush’ were grown in pots in a greenhouse, with 15 seeds sown in each pot on 3 Sep 2018. The pots were moved into a propagation room 15 d after seeding and spaced evenly apart to prevent them from touching. Plants were infested with TSSM 15 d after seeding by placing three infested lima bean leaves taken from a laboratory colony on plants within each pot. The colony was established on lima bean in Apr 2018 from TSSM collected from a commercial strawberry field in Mt. Pleasant, SC. Movement of the mites onto the new plants occurred for 4 d, and then pots were sorted into replicates by level of visible damage. The experiment was RCBD, with each replicate consisting of a single pot. There were five replicates, for a total of 25 pots (5 treatments × 5 replicates). Treatments were water check, Portal (industry standard), Acaritouch sprayed once, Portal + Acaritouch, and Acaritouch sprayed twice. All plants from a treatment were grouped together and sprayed outdoors with 100 ml (to dripping) of the appropriate pesticide solution or water using a spray bottle. Solutions were mixed according to the surface area of the pot. All treatments except the water check were mixed with Induce at 0.25% v/v. The second spray of Acaritouch occurred 3 d after the first. After residues dried, plants were placed back into the propagation room. TSSM eggs and motiles were counted at 3, 7, 10, and 14 DAT by removing three leaves at random per plant and counting mites under a dissecting microscope. All DAT time points refer to the first application. Data were analyzed using a generalized linear mixed model in SAS (PROC GLIMMIX), specifying a negative binomial distribution for count data. Replicate was treated as a random effect. Treatments were compared using least-squared means at P < 0.05. At 3 DAT, there were no significant differences between the numbers of eggs or motiles in any of the treatments (Table 1). However, both treatments containing Portal had numerically fewer motile TSSM than the other three treatments. At 7 DAT, the numbers of eggs and motiles in the two treatments containing Portal were significantly lower than in the other treatments and statistically similar to each other (Table 1). At 10 DAT, the Acaritouch 2× was the only treatment with egg numbers that did not significantly differ from the check. Numerically, the egg numbers in this treatment were much lower than those in the check, but variability within treatments was high. Acaritouch 2× was also statistically similar to Portal alone and Acaritouch 1× at this time point. The three best treatments for egg reduction, which did not statistically differ, were Portal alone, Acaritouch 1×, and Portal+Acaritouch. For motiles, Acaritouch 1× did not differ from the check. Acaritouch 2× was intermediate, and Portal and Portal+Acaritouch were the best treatments. At 14 DAT, there were no statistical differences among treatments in either egg or motile counts (Table 1). Egg counts substantially decreased at this time point compared with previous evaluations, likely because of the reduced quality of the plants due to mite feeding. Differences in motiles were marginally nonsignificant, with numerically fewer motiles in the Portal, Acaritouch 1×, and Portal+Acaritouch treatments. In general, adding Acaritouch to Portal did not increase efficacy over Portal alone. Acaritouch alone, when applied twice, may be slightly more effective than the water check. Table 1. 3 DAT 7 DAT 10 DAT 14 DAT Treatment/formulation Rate Eggs Motiles Eggs Motiles Eggs Motiles Eggs Motiles Water check – 214a 131a 464a 234a 279a 312a 19a 432a Portal XLO 32 fl oz/acre 205a 85a 25b 44b 30bc 51c 23a 127a Acaritouch 1× 25 fl oz/100 gal 301a 134a 479a 358a 76bc 292a 9a 178a Portal XLO + Acaritouch 32 fl oz/acre + 25 fl oz/100 gal 215a 48a 16b 35b 21c 47c 15a 106a Acaritouch 2× 25 fl oz/100 gal 360a 141a 557a 350a 97ab 182b 22a 341a F4, 16 1.61 2.61 25.73 20.51 5.64 32.96 0.27 2.51 P 0.22 0.08 <0.01 <0.01 0.01 <0.01 0.90 0.08 3 DAT 7 DAT 10 DAT 14 DAT Treatment/formulation Rate Eggs Motiles Eggs Motiles Eggs Motiles Eggs Motiles Water check – 214a 131a 464a 234a 279a 312a 19a 432a Portal XLO 32 fl oz/acre 205a 85a 25b 44b 30bc 51c 23a 127a Acaritouch 1× 25 fl oz/100 gal 301a 134a 479a 358a 76bc 292a 9a 178a Portal XLO + Acaritouch 32 fl oz/acre + 25 fl oz/100 gal 215a 48a 16b 35b 21c 47c 15a 106a Acaritouch 2× 25 fl oz/100 gal 360a 141a 557a 350a 97ab 182b 22a 341a F4, 16 1.61 2.61 25.73 20.51 5.64 32.96 0.27 2.51 P 0.22 0.08 <0.01 <0.01 0.01 <0.01 0.90 0.08 Means within columns followed by the same letter are not significantly different; P > 0.05. Open in new tab Table 1. 3 DAT 7 DAT 10 DAT 14 DAT Treatment/formulation Rate Eggs Motiles Eggs Motiles Eggs Motiles Eggs Motiles Water check – 214a 131a 464a 234a 279a 312a 19a 432a Portal XLO 32 fl oz/acre 205a 85a 25b 44b 30bc 51c 23a 127a Acaritouch 1× 25 fl oz/100 gal 301a 134a 479a 358a 76bc 292a 9a 178a Portal XLO + Acaritouch 32 fl oz/acre + 25 fl oz/100 gal 215a 48a 16b 35b 21c 47c 15a 106a Acaritouch 2× 25 fl oz/100 gal 360a 141a 557a 350a 97ab 182b 22a 341a F4, 16 1.61 2.61 25.73 20.51 5.64 32.96 0.27 2.51 P 0.22 0.08 <0.01 <0.01 0.01 <0.01 0.90 0.08 3 DAT 7 DAT 10 DAT 14 DAT Treatment/formulation Rate Eggs Motiles Eggs Motiles Eggs Motiles Eggs Motiles Water check – 214a 131a 464a 234a 279a 312a 19a 432a Portal XLO 32 fl oz/acre 205a 85a 25b 44b 30bc 51c 23a 127a Acaritouch 1× 25 fl oz/100 gal 301a 134a 479a 358a 76bc 292a 9a 178a Portal XLO + Acaritouch 32 fl oz/acre + 25 fl oz/100 gal 215a 48a 16b 35b 21c 47c 15a 106a Acaritouch 2× 25 fl oz/100 gal 360a 141a 557a 350a 97ab 182b 22a 341a F4, 16 1.61 2.61 25.73 20.51 5.64 32.96 0.27 2.51 P 0.22 0.08 <0.01 <0.01 0.01 <0.01 0.90 0.08 Means within columns followed by the same letter are not significantly different; P > 0.05. Open in new tab This research was supported in part by industry gifts of pesticide and research funding. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. Published by Oxford University Press on behalf of Entomological Society of America 2019. This work is written by (a) US Government employee(s) and is in the public domain in the US. This Open Access article contains public sector information licensed under the Open Government Licence v2.0 (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/2/).

Bradford, Benjamin, Z;Chapman, Scott, A;Crubaugh, Linda, K;Groves, Russell, L

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz045

Potato | Solanum tuberosum L Potato aphid | Macrosiphum euphorbiae (Thomas) The objective of this experiment was to evaluate the performance of several experimental foliar treatments for the control of aphids on potato relative to commercial standards and an untreated check. Experimental plots were established on a commercial potato field near Coloma, Wisconsin (44.027462, −89.605643) on a loamy sand soil in 2018. Potato, Solanum tuberosum cv. ‘Atlantic’ was machine planted on 25 Apr with a 1-ft seed spacing and 3-ft row spacing. In early August, a portion of this field was divided into four replicates of 13 treatment plots and one untreated check plot arranged in an RCB design. Two-row plots measured 6 ft by 20 ft and were separated by either one untreated guard row or 5 ft of untreated plants along rows. The field received standard commercial fungicide and insecticide programs prior to plot initiation. Foliar treatments were applied on 6 Aug (Table 1). Treatments were applied with a CO2-pressurized backpack sprayer with a 6-ft boom operating at 30 psi delivering 20 gpa through 4 flat-fan nozzles (Tee Jet XR8002XR) spaced 18 apart while travelling at 3.5 ft/s. No signs of phototoxicity were observed. Table 1. Trt no. Producta Rate (amt/acre) Mean aphid countb 10 Aug (4 DAT) 13 Aug (7 DAT) 1 Untreated check 174.25 c 286.00 cd 2 EXP-1 Low 271.00 c 229.50 cd 3 EXP-1 Med 236.00 c 108.50 bcd 4 EXP-1 High 149.50 bc 47.00 abc 5 Movento 240SC 3.99 fl oz 178.50 bc 53.50 abc 6 Movento 240SC 5 fl oz 82.00 abc 55.75 abc 7 Actara 25WG 3 oz wt 19.75 a 12.25 a 8 Fulfill 50SC 2.74 oz wt 110.50 bc 47.75 abc 9 EXP-2 304.50 c 416.50 d 10 EXP-3 253.50 c 188.75 cd 11 Exirel 100OD 20 fl oz 102.25 abc 58.00 abc 12 Sivanto 200SL 10.5 fl oz 59.25 abc 46.25 abc 13 Transform 240SC 1.5 fl oz 26.25 ab 25.25 ab 14 BeLeaf 50SG 2.8 oz wt 61.75 abc 20.75 ab P <0.0001 <0.0001 Trt no. Producta Rate (amt/acre) Mean aphid countb 10 Aug (4 DAT) 13 Aug (7 DAT) 1 Untreated check 174.25 c 286.00 cd 2 EXP-1 Low 271.00 c 229.50 cd 3 EXP-1 Med 236.00 c 108.50 bcd 4 EXP-1 High 149.50 bc 47.00 abc 5 Movento 240SC 3.99 fl oz 178.50 bc 53.50 abc 6 Movento 240SC 5 fl oz 82.00 abc 55.75 abc 7 Actara 25WG 3 oz wt 19.75 a 12.25 a 8 Fulfill 50SC 2.74 oz wt 110.50 bc 47.75 abc 9 EXP-2 304.50 c 416.50 d 10 EXP-3 253.50 c 188.75 cd 11 Exirel 100OD 20 fl oz 102.25 abc 58.00 abc 12 Sivanto 200SL 10.5 fl oz 59.25 abc 46.25 abc 13 Transform 240SC 1.5 fl oz 26.25 ab 25.25 ab 14 BeLeaf 50SG 2.8 oz wt 61.75 abc 20.75 ab P <0.0001 <0.0001 aAll treatments include 0.25% Dyne-Amic added except untreated check. bMeans followed by the same letter are not significantly different (Tukey’s HSD, α = .05). Open in new tab Table 1. Trt no. Producta Rate (amt/acre) Mean aphid countb 10 Aug (4 DAT) 13 Aug (7 DAT) 1 Untreated check 174.25 c 286.00 cd 2 EXP-1 Low 271.00 c 229.50 cd 3 EXP-1 Med 236.00 c 108.50 bcd 4 EXP-1 High 149.50 bc 47.00 abc 5 Movento 240SC 3.99 fl oz 178.50 bc 53.50 abc 6 Movento 240SC 5 fl oz 82.00 abc 55.75 abc 7 Actara 25WG 3 oz wt 19.75 a 12.25 a 8 Fulfill 50SC 2.74 oz wt 110.50 bc 47.75 abc 9 EXP-2 304.50 c 416.50 d 10 EXP-3 253.50 c 188.75 cd 11 Exirel 100OD 20 fl oz 102.25 abc 58.00 abc 12 Sivanto 200SL 10.5 fl oz 59.25 abc 46.25 abc 13 Transform 240SC 1.5 fl oz 26.25 ab 25.25 ab 14 BeLeaf 50SG 2.8 oz wt 61.75 abc 20.75 ab P <0.0001 <0.0001 Trt no. Producta Rate (amt/acre) Mean aphid countb 10 Aug (4 DAT) 13 Aug (7 DAT) 1 Untreated check 174.25 c 286.00 cd 2 EXP-1 Low 271.00 c 229.50 cd 3 EXP-1 Med 236.00 c 108.50 bcd 4 EXP-1 High 149.50 bc 47.00 abc 5 Movento 240SC 3.99 fl oz 178.50 bc 53.50 abc 6 Movento 240SC 5 fl oz 82.00 abc 55.75 abc 7 Actara 25WG 3 oz wt 19.75 a 12.25 a 8 Fulfill 50SC 2.74 oz wt 110.50 bc 47.75 abc 9 EXP-2 304.50 c 416.50 d 10 EXP-3 253.50 c 188.75 cd 11 Exirel 100OD 20 fl oz 102.25 abc 58.00 abc 12 Sivanto 200SL 10.5 fl oz 59.25 abc 46.25 abc 13 Transform 240SC 1.5 fl oz 26.25 ab 25.25 ab 14 BeLeaf 50SG 2.8 oz wt 61.75 abc 20.75 ab P <0.0001 <0.0001 aAll treatments include 0.25% Dyne-Amic added except untreated check. bMeans followed by the same letter are not significantly different (Tukey’s HSD, α = .05). Open in new tab Populations of potato aphid, Macrosiphum euphorbiae, were assessed by counting the number of adults and nymphs on 25 randomly selected leaves in each plot. Insect counts occurred on 10 Aug and 13 Aug (4 and 7 days after application, respectively). Insect count data were log transformed prior to analysis. Treatment main effects were determined using analysis of variance. Means separation letter codes were generated using Tukey’s HSD procedure (α = .05). Aphid counts in the Actara and Transform treatments were significantly lower than the untreated check on 10 Aug, 4 days after treatment (Table 1). On 13 Aug (7 DAT), all of the registered commercial products outperformed the untreated check, with Actara and Transform continuing to perform better than the other treatments. One factor affecting the performance of the experimental treatments is the application of fungicide to the field in the weeks proceeding the initiation of the experiment, as these experimental compounds were biologics susceptible to fungicide residues. This research was supported by direct industry funding. © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Haviland, David, R;Rill, Stephanie, M;Son,, Youngsoo

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz086

Shiny xylosma | Xylosma congestum Photinia sp. | Photinia fraseri flupyradifurone This study was conducted to evaluate two rates of flupyradifurone (Altus, Bayer CropSciences) for its efficacy against GWSS on three ornamental hosts that are common in urban regions of California’s central valley. Twelve plants of each Xylosma sp., Photinia sp., and Euonymous sp. growing in 1-gal pots were used to compare three treatments: Altus 14 fl oz, Altus 7 fl oz, and a water-only check. Assignments were made such that the data could be evaluated as a completely randomized design of nine treatments by four replications (3 hosts × 3 treatments × 4 replicates). On 23 Aug, a spray bottle was used to treat each shrub using 160 ml of insecticide solution (to runoff) equivalent to 200 gal of water per acre. The effects of insecticide residues on GWSS mortality were evaluated at weekly intervals by caging adult GWSS onto the treated foliage using 5-gal paint strainer bags. Adult GWSS were collected each week from a local organic citrus orchard; ten mixed-gender adults were placed into a bag (1 cage per tree). On the day of treatment, the spray residues were allowed to dry for approximately 1 h and then one bag per plant containing the adults was placed onto each of the 36 plants. Mortality of GWSS within the bags was recorded 7 d later (1 WAT) by removing the bag and counting the dead and live adults. A new cage with new adults was placed onto the plant weekly for 6 wk after the initial application. Percentage mortality among treatments was compared by ANOVA with means separated by Fisher’s Protected LSD (P ≤ 0.05) after arcsine transformation. Both rates of Altus had significant effects on GWSS mortality (Table 1). During the first WAT, both rates of Altus on all three ornamental hosts provided 100% GWSS control, compared with 18.8 to 78.6% mortality in the check. Both rates of Altus continued to provide >90% GWSS mortality in all rate and host combinations 2 and 3 WAT compared with 0 to 22.5% mortality in the check. This trend continued 4–6 WAT with highly significant GWSS mortality for all rates and host combinations where Altus was applied. Table 1. Plant variety . Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Euonymous Water check – 18.8c 10.0c 22.5c 5.3c 0.0d 6.3c Photinia Water check – 78.6b 10.0c 17.0c 10.0c 0.0d 9.4c Xylosma Water check – 22.3c 10.0c 0.0c 7.5c 6.7d 5.0c Euonymous Altus 14 fl oz 100.0a 95.0ab 100.0a 97.5a 91.7ab 100.0a Photinia Altus 14 fl oz 100.0a 100.0a 97.5ab 97.5a 94.4a 84.3ab Xylosma Altus 14 fl oz 100.0a 90.0b 100.0a 84.0ab 68.0c 83.2ab Euonymous Altus 7 fl oz 100.0a 100.0a 100.0a 92.5ab 94.7ab 68.9b Photinia Altus 7 fl oz 100.0a 100.0a 97.5ab 78.1b 69.6bc 82.6b Xylosma Altus 7 fl oz 100.0a 97.5ab 92.5b 72.5b 79.7abc 63.5b F 160.25 43.37 67.07 15.41 13.03 9.07 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Plant variety . Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Euonymous Water check – 18.8c 10.0c 22.5c 5.3c 0.0d 6.3c Photinia Water check – 78.6b 10.0c 17.0c 10.0c 0.0d 9.4c Xylosma Water check – 22.3c 10.0c 0.0c 7.5c 6.7d 5.0c Euonymous Altus 14 fl oz 100.0a 95.0ab 100.0a 97.5a 91.7ab 100.0a Photinia Altus 14 fl oz 100.0a 100.0a 97.5ab 97.5a 94.4a 84.3ab Xylosma Altus 14 fl oz 100.0a 90.0b 100.0a 84.0ab 68.0c 83.2ab Euonymous Altus 7 fl oz 100.0a 100.0a 100.0a 92.5ab 94.7ab 68.9b Photinia Altus 7 fl oz 100.0a 100.0a 97.5ab 78.1b 69.6bc 82.6b Xylosma Altus 7 fl oz 100.0a 97.5ab 92.5b 72.5b 79.7abc 63.5b F 160.25 43.37 67.07 15.41 13.03 9.07 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Means in a column followed by the same letter are not significantly different, P ≤ 0.05, FPLSD after arcsin transformation of the percentage mortality. Original means are shown. aRate of formulated product per 200 gal of water, sprayed to runoff. bPercentage mortality of GWSS exposed to pesticide residues for 7-d periods from 1 to 6 weeks after treatment (WAT). Open in new tab Table 1. Plant variety . Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Euonymous Water check – 18.8c 10.0c 22.5c 5.3c 0.0d 6.3c Photinia Water check – 78.6b 10.0c 17.0c 10.0c 0.0d 9.4c Xylosma Water check – 22.3c 10.0c 0.0c 7.5c 6.7d 5.0c Euonymous Altus 14 fl oz 100.0a 95.0ab 100.0a 97.5a 91.7ab 100.0a Photinia Altus 14 fl oz 100.0a 100.0a 97.5ab 97.5a 94.4a 84.3ab Xylosma Altus 14 fl oz 100.0a 90.0b 100.0a 84.0ab 68.0c 83.2ab Euonymous Altus 7 fl oz 100.0a 100.0a 100.0a 92.5ab 94.7ab 68.9b Photinia Altus 7 fl oz 100.0a 100.0a 97.5ab 78.1b 69.6bc 82.6b Xylosma Altus 7 fl oz 100.0a 97.5ab 92.5b 72.5b 79.7abc 63.5b F 160.25 43.37 67.07 15.41 13.03 9.07 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Plant variety . Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Euonymous Water check – 18.8c 10.0c 22.5c 5.3c 0.0d 6.3c Photinia Water check – 78.6b 10.0c 17.0c 10.0c 0.0d 9.4c Xylosma Water check – 22.3c 10.0c 0.0c 7.5c 6.7d 5.0c Euonymous Altus 14 fl oz 100.0a 95.0ab 100.0a 97.5a 91.7ab 100.0a Photinia Altus 14 fl oz 100.0a 100.0a 97.5ab 97.5a 94.4a 84.3ab Xylosma Altus 14 fl oz 100.0a 90.0b 100.0a 84.0ab 68.0c 83.2ab Euonymous Altus 7 fl oz 100.0a 100.0a 100.0a 92.5ab 94.7ab 68.9b Photinia Altus 7 fl oz 100.0a 100.0a 97.5ab 78.1b 69.6bc 82.6b Xylosma Altus 7 fl oz 100.0a 97.5ab 92.5b 72.5b 79.7abc 63.5b F 160.25 43.37 67.07 15.41 13.03 9.07 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Means in a column followed by the same letter are not significantly different, P ≤ 0.05, FPLSD after arcsin transformation of the percentage mortality. Original means are shown. aRate of formulated product per 200 gal of water, sprayed to runoff. bPercentage mortality of GWSS exposed to pesticide residues for 7-d periods from 1 to 6 weeks after treatment (WAT). Open in new tab Since there was no host by treatment interaction, numbers were pooled across plant species (Table 2). There were no significant differences between the two Altus rates through 3 WAT. By 4 WAT, the high rate of Altus provided improved mortality compared with the low rate. By 5 WAT, mortality rates of the high rate continued to be numerically, but not statically, higher than the low rate for the remainder of the trial. Table 2. Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Water check – 39.9b 10.0b 13.2b 7.6c 2.2b 6.9c Altus 14 fl oz 100.0a 95.0a 99.2a 93.1a 84.8a 89.3a Altus 7 fl oz 100.0a 99.2a 96.7a 81.1b 81.3a 71.8b F 108.89 173.61 209.68 56.03 38.75 34.76 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Water check – 39.9b 10.0b 13.2b 7.6c 2.2b 6.9c Altus 14 fl oz 100.0a 95.0a 99.2a 93.1a 84.8a 89.3a Altus 7 fl oz 100.0a 99.2a 96.7a 81.1b 81.3a 71.8b F 108.89 173.61 209.68 56.03 38.75 34.76 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Means in a column followed by the same letter are not significantly different, P > 0.05, FPLSD after arcsin transformation of the percentage mortality. Original means are shown. aRate of formulated product per 200 gal of water, sprayed to runoff. bPercentage mortality of GWSS exposed to pesticide residues for 7-d periods from 1 to 6 weeks after treatment (WAT). Open in new tab Table 2. Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Water check – 39.9b 10.0b 13.2b 7.6c 2.2b 6.9c Altus 14 fl oz 100.0a 95.0a 99.2a 93.1a 84.8a 89.3a Altus 7 fl oz 100.0a 99.2a 96.7a 81.1b 81.3a 71.8b F 108.89 173.61 209.68 56.03 38.75 34.76 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Treatment/formulation . Rate/acrea . Mean GWSS mortality (%)b . . . 1 WAT . 2 WAT . 3 WAT . 4 WAT . 5 WAT . 6 WAT . Water check – 39.9b 10.0b 13.2b 7.6c 2.2b 6.9c Altus 14 fl oz 100.0a 95.0a 99.2a 93.1a 84.8a 89.3a Altus 7 fl oz 100.0a 99.2a 96.7a 81.1b 81.3a 71.8b F 108.89 173.61 209.68 56.03 38.75 34.76 P <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 Means in a column followed by the same letter are not significantly different, P > 0.05, FPLSD after arcsin transformation of the percentage mortality. Original means are shown. aRate of formulated product per 200 gal of water, sprayed to runoff. bPercentage mortality of GWSS exposed to pesticide residues for 7-d periods from 1 to 6 weeks after treatment (WAT). Open in new tab This research was supported by the Consolidated Central Valley Table Grape Pest and Disease Control District. © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Vafaie,, Erfan;Heinz, Kevin, M

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz047

The purpose of this study was to determine the efficacy of several insecticides and commercially available biological control agents to manage silverleaf whiteflies on greenhouse grown, 6-inch potted poinsettias. The trial was conducted between Apr 6 and May 18, 2018 in a research greenhouse located at the AgriLife Research & Extension Center in Overton, TX. Poinsettia plants were infested after covering the group of plants with row cover material (Row Cover Deluxe; Greenhouse Megastore, Danville, IL) and then releasing two adult whiteflies per plant per week for two consecutive weeks. After the infestation, individual plants were moved inside 47.5- × 47.5- × 47.5-cm netted observation cages (44545F; MegaView Science Co., Ltd., Talchung, Taiwan). Treatments were assigned to individual caged poinsettia plants under a CRD, with five replicates. Treatments were applied as either as foliar sprays or broadcast natural enemy releases (Table 1). Broadcast releases were made by placing 3 ml of bulk Eretmocerus eremicus Rose and Zolnerowich (Hymenoptera: Aphelinidae) pupae or 1 teaspoon of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) plus the carrier material on the soil surface. Natural enemy release rates were purposefully high and used for proof-of-concept to assess whitefly control in East Texas greenhouses. All foliar sprays were made with an R&D CO2 sprayer (Model D-203S) fitted with a 601FA single nozzle spray boom (Bellspray, Inc., Opelousas, LA), until runoff. Assessments included inspection of all poinsettia leaves (top and bottom) on each plant using a 3.5× head magnifying lens. Counts included nymphs, pupae, exuviae, and whitefly adults and phytotoxicity ratings (0–10) at 0, 6, 13, 27, and 41 DAT. Only whitefly nymph and pupae data are included in this report. Log-transformed count data were compared using ANOVA (P < 0.05) and Dunnett’s post hoc test with untreated check as the control group. Table 1. No. Treatment/formulation Active ingredient Application rate Application method Date (days after initial treatment) 04/07 (0) 04/13 (6) 04/20 (13) 04/27 (20) 05/04 (28) 1 Pycana Pyrethrins + Canola oil 1% v/v Foliar X X 2 Pycana Pyrethrins + Canola oil 1.5% v/v Foliar X X 3 Pycana Pyrethrins + Canola oil 2% v/v Foliar X X 4 Pyganic Pyrethrins 2 fl oz/gal Foliar X X 5 Fulcrum Pyriproxifen 8 fl oz/100 gal Foliar X X 6 Ventigra Afidopyropen 4.8 fl oz/100 gal Foliar X X 7 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X 8 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X X 9 Endeavor Pymetrozine 5 oz/100 gal Foliar X X 10 E. eremicus – 215 pupae per plant Broadcast X X X X X 11 A. swirskii – 250 mites per plant Broadcast X X 12 E. eremicus + A. swirskii – ~215 pupae + ~250 mites per plant Broadcast X X* X* X* X 13 UTC – – – No. Treatment/formulation Active ingredient Application rate Application method Date (days after initial treatment) 04/07 (0) 04/13 (6) 04/20 (13) 04/27 (20) 05/04 (28) 1 Pycana Pyrethrins + Canola oil 1% v/v Foliar X X 2 Pycana Pyrethrins + Canola oil 1.5% v/v Foliar X X 3 Pycana Pyrethrins + Canola oil 2% v/v Foliar X X 4 Pyganic Pyrethrins 2 fl oz/gal Foliar X X 5 Fulcrum Pyriproxifen 8 fl oz/100 gal Foliar X X 6 Ventigra Afidopyropen 4.8 fl oz/100 gal Foliar X X 7 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X 8 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X X 9 Endeavor Pymetrozine 5 oz/100 gal Foliar X X 10 E. eremicus – 215 pupae per plant Broadcast X X X X X 11 A. swirskii – 250 mites per plant Broadcast X X 12 E. eremicus + A. swirskii – ~215 pupae + ~250 mites per plant Broadcast X X* X* X* X 13 UTC – – – *Sampling weeks in which only E. eremicus was released in the ‘E. eremicus + A. swirskii’ treatment. Open in new tab Table 1. No. Treatment/formulation Active ingredient Application rate Application method Date (days after initial treatment) 04/07 (0) 04/13 (6) 04/20 (13) 04/27 (20) 05/04 (28) 1 Pycana Pyrethrins + Canola oil 1% v/v Foliar X X 2 Pycana Pyrethrins + Canola oil 1.5% v/v Foliar X X 3 Pycana Pyrethrins + Canola oil 2% v/v Foliar X X 4 Pyganic Pyrethrins 2 fl oz/gal Foliar X X 5 Fulcrum Pyriproxifen 8 fl oz/100 gal Foliar X X 6 Ventigra Afidopyropen 4.8 fl oz/100 gal Foliar X X 7 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X 8 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X X 9 Endeavor Pymetrozine 5 oz/100 gal Foliar X X 10 E. eremicus – 215 pupae per plant Broadcast X X X X X 11 A. swirskii – 250 mites per plant Broadcast X X 12 E. eremicus + A. swirskii – ~215 pupae + ~250 mites per plant Broadcast X X* X* X* X 13 UTC – – – No. Treatment/formulation Active ingredient Application rate Application method Date (days after initial treatment) 04/07 (0) 04/13 (6) 04/20 (13) 04/27 (20) 05/04 (28) 1 Pycana Pyrethrins + Canola oil 1% v/v Foliar X X 2 Pycana Pyrethrins + Canola oil 1.5% v/v Foliar X X 3 Pycana Pyrethrins + Canola oil 2% v/v Foliar X X 4 Pyganic Pyrethrins 2 fl oz/gal Foliar X X 5 Fulcrum Pyriproxifen 8 fl oz/100 gal Foliar X X 6 Ventigra Afidopyropen 4.8 fl oz/100 gal Foliar X X 7 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X 8 Ventigra Afidopyropen 7.0 fl oz/100 gal Foliar X X 9 Endeavor Pymetrozine 5 oz/100 gal Foliar X X 10 E. eremicus – 215 pupae per plant Broadcast X X X X X 11 A. swirskii – 250 mites per plant Broadcast X X 12 E. eremicus + A. swirskii – ~215 pupae + ~250 mites per plant Broadcast X X* X* X* X 13 UTC – – – *Sampling weeks in which only E. eremicus was released in the ‘E. eremicus + A. swirskii’ treatment. Open in new tab At 27 DAT, Pycana (1, 1.5, and 2%), Fulcrum, Ventigra (7.0 fl oz/100 gal applied twice), and the combination of E. eremicus + A. swirskii were significantly different from the untreated check for number of whitefly nymphs (Table 2). At 41 DAT, Pycana (1 and 1.5%), Ventigra (4.8 fl oz/100 gal applied once and 7.0 fl oz/100 gal applied twice), E. eremicus, and the combination of E. eremicus + A. swirskii were significantly different from the untreated check for number of whitefly nymphs (Table 2). Table 2. No. Treatment Mean whitefly nymphs per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 42 39 30 10.2* 119.2* 2 Pycana 40.4 16 13 55.4* 41.2* 3 Pycana 40 67.25 27.4 11.2* 129.8 4 Pyganic 40.6 46.2 28.8 61.4 105.2 5 Fulcrum 40.2 47.8 27.6 7.4* 0* 6 Ventigra 40.6 47.2 56.6 21.6 26* 7 Ventigra 42 44.2 35.6 34.2 86.4 8 Ventigra 43.2 63.4 70.2 24.4* 59.6* 9 Endeavor 44 64.4 73.2 69 438 10 E. eremicus 44.2 25.5 65 82.6 25.2* 11 A. swirskii 42.6 56.4 72.4 68 246 12 E. eremicus + A. swirskii 44 15.4 26 13.6* 8.2* 13 UTC 41.6 50.6 75.8 199.6 554.8 P 1.00 0.40 0.11 <0.001 <0.001 No. Treatment Mean whitefly nymphs per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 42 39 30 10.2* 119.2* 2 Pycana 40.4 16 13 55.4* 41.2* 3 Pycana 40 67.25 27.4 11.2* 129.8 4 Pyganic 40.6 46.2 28.8 61.4 105.2 5 Fulcrum 40.2 47.8 27.6 7.4* 0* 6 Ventigra 40.6 47.2 56.6 21.6 26* 7 Ventigra 42 44.2 35.6 34.2 86.4 8 Ventigra 43.2 63.4 70.2 24.4* 59.6* 9 Endeavor 44 64.4 73.2 69 438 10 E. eremicus 44.2 25.5 65 82.6 25.2* 11 A. swirskii 42.6 56.4 72.4 68 246 12 E. eremicus + A. swirskii 44 15.4 26 13.6* 8.2* 13 UTC 41.6 50.6 75.8 199.6 554.8 P 1.00 0.40 0.11 <0.001 <0.001 *Significantly different compared with untreated check (UTC) (P < 0.05) using Dunnett’s Method on log-transformed (log(x + 1)) data within a column. Open in new tab Table 2. No. Treatment Mean whitefly nymphs per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 42 39 30 10.2* 119.2* 2 Pycana 40.4 16 13 55.4* 41.2* 3 Pycana 40 67.25 27.4 11.2* 129.8 4 Pyganic 40.6 46.2 28.8 61.4 105.2 5 Fulcrum 40.2 47.8 27.6 7.4* 0* 6 Ventigra 40.6 47.2 56.6 21.6 26* 7 Ventigra 42 44.2 35.6 34.2 86.4 8 Ventigra 43.2 63.4 70.2 24.4* 59.6* 9 Endeavor 44 64.4 73.2 69 438 10 E. eremicus 44.2 25.5 65 82.6 25.2* 11 A. swirskii 42.6 56.4 72.4 68 246 12 E. eremicus + A. swirskii 44 15.4 26 13.6* 8.2* 13 UTC 41.6 50.6 75.8 199.6 554.8 P 1.00 0.40 0.11 <0.001 <0.001 No. Treatment Mean whitefly nymphs per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 42 39 30 10.2* 119.2* 2 Pycana 40.4 16 13 55.4* 41.2* 3 Pycana 40 67.25 27.4 11.2* 129.8 4 Pyganic 40.6 46.2 28.8 61.4 105.2 5 Fulcrum 40.2 47.8 27.6 7.4* 0* 6 Ventigra 40.6 47.2 56.6 21.6 26* 7 Ventigra 42 44.2 35.6 34.2 86.4 8 Ventigra 43.2 63.4 70.2 24.4* 59.6* 9 Endeavor 44 64.4 73.2 69 438 10 E. eremicus 44.2 25.5 65 82.6 25.2* 11 A. swirskii 42.6 56.4 72.4 68 246 12 E. eremicus + A. swirskii 44 15.4 26 13.6* 8.2* 13 UTC 41.6 50.6 75.8 199.6 554.8 P 1.00 0.40 0.11 <0.001 <0.001 *Significantly different compared with untreated check (UTC) (P < 0.05) using Dunnett’s Method on log-transformed (log(x + 1)) data within a column. Open in new tab At 27 DAT, Pycana (1%), Ventigra (7.0 fl oz/100 gal applied once), and combination of E. eremicus + A. swirskii were significantly different from the untreated check for number of whitefly pupae. At 41 DAT, Pycana (1 and 1.5%), Fulcrum, and Ventigra (7.0 fl oz/100 gal applied twice) were significantly different from the untreated check for number of whitefly pupae (Table 3). No treatments produced any signs of phytotoxicity. Table 3. No. Treatment Mean whitefly pupae per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 4.6 8.5 8.6 7.4* 17.6* 2 Pycana 3.2 17 8.4 25 43.2* 3 Pycana 4.2 7 3.2 17.8 17.4 4 Pyganic 3.2 8.5 4.8 32.6 32.8 5 Fulcrum 0.4 11.25 13.8 23 1.2* 6 Ventigra 1.6 8.25 11.8 17 8 7 Ventigra 4.2 9.2 8.6 7* 30.8 8 Ventigra 4.4 12.25 13.6 17.6 3.6* 9 Endeavor 6.6 18.8 21.2 60 125.8 10 E. eremicus 2 6 5 24.4 31.4 11 A. swirskii 6 18 15.4 26.4 90.4 12 E. eremicus + A. swirskii 3.4 8 4.2 5.4* 9.2 13 UTC 6.8 15.75 20.8 55 123.6 P 0.64 0.87 0.09 0.02 <0.001 No. Treatment Mean whitefly pupae per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 4.6 8.5 8.6 7.4* 17.6* 2 Pycana 3.2 17 8.4 25 43.2* 3 Pycana 4.2 7 3.2 17.8 17.4 4 Pyganic 3.2 8.5 4.8 32.6 32.8 5 Fulcrum 0.4 11.25 13.8 23 1.2* 6 Ventigra 1.6 8.25 11.8 17 8 7 Ventigra 4.2 9.2 8.6 7* 30.8 8 Ventigra 4.4 12.25 13.6 17.6 3.6* 9 Endeavor 6.6 18.8 21.2 60 125.8 10 E. eremicus 2 6 5 24.4 31.4 11 A. swirskii 6 18 15.4 26.4 90.4 12 E. eremicus + A. swirskii 3.4 8 4.2 5.4* 9.2 13 UTC 6.8 15.75 20.8 55 123.6 P 0.64 0.87 0.09 0.02 <0.001 *Significantly different compared with untreated check (UTC) (P < 0.05) using Dunnett’s Method on log-transformed (log(x + 1)) data within a column. Open in new tab Table 3. No. Treatment Mean whitefly pupae per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 4.6 8.5 8.6 7.4* 17.6* 2 Pycana 3.2 17 8.4 25 43.2* 3 Pycana 4.2 7 3.2 17.8 17.4 4 Pyganic 3.2 8.5 4.8 32.6 32.8 5 Fulcrum 0.4 11.25 13.8 23 1.2* 6 Ventigra 1.6 8.25 11.8 17 8 7 Ventigra 4.2 9.2 8.6 7* 30.8 8 Ventigra 4.4 12.25 13.6 17.6 3.6* 9 Endeavor 6.6 18.8 21.2 60 125.8 10 E. eremicus 2 6 5 24.4 31.4 11 A. swirskii 6 18 15.4 26.4 90.4 12 E. eremicus + A. swirskii 3.4 8 4.2 5.4* 9.2 13 UTC 6.8 15.75 20.8 55 123.6 P 0.64 0.87 0.09 0.02 <0.001 No. Treatment Mean whitefly pupae per pot 1 DAT 6 DAT 13 DAT 27 DAT 41 DAT 6 Apr 13 Apr 20 Apr 4 May 18 May 1 Pycana 4.6 8.5 8.6 7.4* 17.6* 2 Pycana 3.2 17 8.4 25 43.2* 3 Pycana 4.2 7 3.2 17.8 17.4 4 Pyganic 3.2 8.5 4.8 32.6 32.8 5 Fulcrum 0.4 11.25 13.8 23 1.2* 6 Ventigra 1.6 8.25 11.8 17 8 7 Ventigra 4.2 9.2 8.6 7* 30.8 8 Ventigra 4.4 12.25 13.6 17.6 3.6* 9 Endeavor 6.6 18.8 21.2 60 125.8 10 E. eremicus 2 6 5 24.4 31.4 11 A. swirskii 6 18 15.4 26.4 90.4 12 E. eremicus + A. swirskii 3.4 8 4.2 5.4* 9.2 13 UTC 6.8 15.75 20.8 55 123.6 P 0.64 0.87 0.09 0.02 <0.001 *Significantly different compared with untreated check (UTC) (P < 0.05) using Dunnett’s Method on log-transformed (log(x + 1)) data within a column. Open in new tab This research was supported by industry funds and gifts in kind of pesticides and natural enemies. © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Burkness, Eric, C;Wold-Burkness, Suzanne, J;Hutchison, William, D

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz007

Corn (hybrid, maize, sweet) | Zea mays Corn earworm (CEW) | Helicoverpa zea (Boddie), European corn borer (ECB) | Ostrinia nubilalis (Hübner) chlorantraniliprole, alkylphenol ethoxylate, indoxacarb, bifenthrin, zeta-cypermethrin, lambda-cyhalothrin The objective of this study was to evaluate the efficacy of insecticide treatments for the control of corn earworm and European corn borer in sweet corn grown in Minnesota. On 29 Jun, ‘Providence’ sweet corn was planted at the University of Minnesota Research and Outreach Center in Rosemount, MN. Seventeen treatments were arranged in an RCB design with four replications. Plots consisted of two rows 25 feet (7.6 m) long with 30-inch (0.8 m) row spacing. A single skip row separated treatments and 10-feet alleys (3.04 m) separated replicates. Insecticide applications were made with a CO2-pressurized backpack sprayer with a 3-feet (0.9 m) 2-nozzle boom with 20-inch (0.5 m) nozzle spacing. Nozzles were XR-Teejet 8002 flat fan nozzles with no screen. The sprayer was calibrated to deliver 25 gpa (233.8 liters/ha) at 35 psi (242 kPa). The ear zone of each row of the two-row plot was treated beginning at 56% silk. A total of four applications were made on the following dates, 23 and 27 Aug, and 3 and 10 Sep. On 14 Sep, 20 primary ears per plot were harvested by skipping the first 3 ears on either end of a row and arbitrarily selecting 10 primary ears from each row. Ears were evaluated for both CEW and ECB and data recorded for total number of larvae, larval size and location, and feeding damage (number of kernels damaged). Ears were also rated for both fresh market and processing marketability. All data were analyzed using ANOVA. Proportion data were arcsine transformed and count data were square root transformed prior to analysis. Untransformed means are presented. Means were separated using a protected LSD (P = 0.05). Only a single ECB larva was found in the untreated check and no ECB were detected in any of the treated plots. Therefore, the main pest in this trial was CEW. Mean total CEW larvae in the untreated check was high at 0.94 per ear (Table 1). All treatments provided a significant reduction in CEW compared with the untreated check except both rates of Steward. Percentage of marketable ears for both fresh market and processing was significantly higher for all treatments compared with the untreated check except for both rates of Steward. Kernel feeding damage was limited to the tip of the ear and was significantly lower in all treatments compared with the untreated check except for the low rate of Steward. Phytotoxicity was not observed among treatments. Table 1. Treatment/formulation Rate per acre Mean number larvae/ear Marketable ears (%) Total damaged kernels/eare Total ECBa Total CEWb (% control) Fresh marketc Processingd Coragen 1.67SC 5.0 fl oz 0.00 0.06 (94)gh 95a 96ab 0.24d Coragen 1.67SC 3.0 fl oz 0.00 0.05 (95)h 94a 95abc 0.36d Coragen 1.67SC + Preference 3.0 fl oz + 0.25% v/v 0.00 0.13 (86)fgh 85bc 89b-e 0.90d Coragen 1.67SC + AG16134 3.0 fl oz + 0.25% v/v 0.00 0.08 (91)fgh 88b 98a 0.63d Coragen 1.67SC + AG17047 3.0 fl oz + 0.25% v/v 0.00 0.16 (83)ef 81bc 88c-f 1.03cd Coragen 1.67SC + Interlock 3.0 fl oz + 2.0 oz 0.00 0.11 (88)e-h 84bc 89b-f 1.21cd Coragen 1.67SC + AG16134 + Interlock 3.0 fl oz + 0.25% v/v + 2.0 fl oz 0.00 0.11 (88)fgh 84bc 94a-d 1.10cd Coragen 1.67SC + AccuDrop 3.0 fl oz + 3.0 fl oz 0.00 0.11 (88)fgh 83bc 93a-d 1.23cd Coragen 1.67SC + AccuDrop + AG16134 3.0 fl oz + 3.0 fl oz + 0.25% v/v 0.00 0.14 (85)efg 83bc 91a-d 0.65d Coragen 1.67SC + Masterlock 3.0 fl oz + 6.4 fl oz 0.00 0.13 (86)efg 85bc 91a-d 0.69d Steward 1.25EC 6.0 fl oz 0.00 0.99 (−5)a 18g 44h 5.33a Steward 1.25EC 10.0 fl oz 0.00 0.65 (31)bc 43ef 58gh 3.51b Brigade 2EC 5.0 fl oz 0.00 0.14 (85)efg 81bc 86def 0.95cd Hero 1.24EC 5.0 fl oz 0.00 0.26 (72)de 73cd 78efg 1.10cd Prevathon 0.43SC 14.0 fl oz 0.00 0.08 (91)fgh 89ab 95a-d 0.46d Warrior II 2.08CS 1.92 fl oz 0.00 0.46 (51)cd 59de 76fg 1.96c Untreated check – 0.01 0.94 (−)ab 26fg 38h 5.88a NS Treatment/formulation Rate per acre Mean number larvae/ear Marketable ears (%) Total damaged kernels/eare Total ECBa Total CEWb (% control) Fresh marketc Processingd Coragen 1.67SC 5.0 fl oz 0.00 0.06 (94)gh 95a 96ab 0.24d Coragen 1.67SC 3.0 fl oz 0.00 0.05 (95)h 94a 95abc 0.36d Coragen 1.67SC + Preference 3.0 fl oz + 0.25% v/v 0.00 0.13 (86)fgh 85bc 89b-e 0.90d Coragen 1.67SC + AG16134 3.0 fl oz + 0.25% v/v 0.00 0.08 (91)fgh 88b 98a 0.63d Coragen 1.67SC + AG17047 3.0 fl oz + 0.25% v/v 0.00 0.16 (83)ef 81bc 88c-f 1.03cd Coragen 1.67SC + Interlock 3.0 fl oz + 2.0 oz 0.00 0.11 (88)e-h 84bc 89b-f 1.21cd Coragen 1.67SC + AG16134 + Interlock 3.0 fl oz + 0.25% v/v + 2.0 fl oz 0.00 0.11 (88)fgh 84bc 94a-d 1.10cd Coragen 1.67SC + AccuDrop 3.0 fl oz + 3.0 fl oz 0.00 0.11 (88)fgh 83bc 93a-d 1.23cd Coragen 1.67SC + AccuDrop + AG16134 3.0 fl oz + 3.0 fl oz + 0.25% v/v 0.00 0.14 (85)efg 83bc 91a-d 0.65d Coragen 1.67SC + Masterlock 3.0 fl oz + 6.4 fl oz 0.00 0.13 (86)efg 85bc 91a-d 0.69d Steward 1.25EC 6.0 fl oz 0.00 0.99 (−5)a 18g 44h 5.33a Steward 1.25EC 10.0 fl oz 0.00 0.65 (31)bc 43ef 58gh 3.51b Brigade 2EC 5.0 fl oz 0.00 0.14 (85)efg 81bc 86def 0.95cd Hero 1.24EC 5.0 fl oz 0.00 0.26 (72)de 73cd 78efg 1.10cd Prevathon 0.43SC 14.0 fl oz 0.00 0.08 (91)fgh 89ab 95a-d 0.46d Warrior II 2.08CS 1.92 fl oz 0.00 0.46 (51)cd 59de 76fg 1.96c Untreated check – 0.01 0.94 (−)ab 26fg 38h 5.88a NS Means within columns followed by the same letter are not significantly different (P > 0.05), Protected Least significant difference Test (LSD). Mean percentage of marketable ears for fresh market and processing were transformed using the arcsine transformation to obtain mean separations using LSD (P = 0.05). Insect counts were transformed using the square root transformation to obtain mean separations using LSD (P = 0.05); untransformed means are presented. NS = not significant. a Includes all ECB instars in the husk, silk, tip, side, butt, or shank of the ear. b Includes all CEW instars in the silk, tip, side, or butt of the ear. c Percentage of ears with no kernel damage or larvae present. d Percentage of ears with only small larvae (1–2 instar ECB and/or 1–2 instar CEW) and/or damage limited to the tip; no damage or larvae on the side or butt of the ear. e Total kernels damaged/ear in the tip, side, or butt by ECB and/or CEW. Open in new tab Table 1. Treatment/formulation Rate per acre Mean number larvae/ear Marketable ears (%) Total damaged kernels/eare Total ECBa Total CEWb (% control) Fresh marketc Processingd Coragen 1.67SC 5.0 fl oz 0.00 0.06 (94)gh 95a 96ab 0.24d Coragen 1.67SC 3.0 fl oz 0.00 0.05 (95)h 94a 95abc 0.36d Coragen 1.67SC + Preference 3.0 fl oz + 0.25% v/v 0.00 0.13 (86)fgh 85bc 89b-e 0.90d Coragen 1.67SC + AG16134 3.0 fl oz + 0.25% v/v 0.00 0.08 (91)fgh 88b 98a 0.63d Coragen 1.67SC + AG17047 3.0 fl oz + 0.25% v/v 0.00 0.16 (83)ef 81bc 88c-f 1.03cd Coragen 1.67SC + Interlock 3.0 fl oz + 2.0 oz 0.00 0.11 (88)e-h 84bc 89b-f 1.21cd Coragen 1.67SC + AG16134 + Interlock 3.0 fl oz + 0.25% v/v + 2.0 fl oz 0.00 0.11 (88)fgh 84bc 94a-d 1.10cd Coragen 1.67SC + AccuDrop 3.0 fl oz + 3.0 fl oz 0.00 0.11 (88)fgh 83bc 93a-d 1.23cd Coragen 1.67SC + AccuDrop + AG16134 3.0 fl oz + 3.0 fl oz + 0.25% v/v 0.00 0.14 (85)efg 83bc 91a-d 0.65d Coragen 1.67SC + Masterlock 3.0 fl oz + 6.4 fl oz 0.00 0.13 (86)efg 85bc 91a-d 0.69d Steward 1.25EC 6.0 fl oz 0.00 0.99 (−5)a 18g 44h 5.33a Steward 1.25EC 10.0 fl oz 0.00 0.65 (31)bc 43ef 58gh 3.51b Brigade 2EC 5.0 fl oz 0.00 0.14 (85)efg 81bc 86def 0.95cd Hero 1.24EC 5.0 fl oz 0.00 0.26 (72)de 73cd 78efg 1.10cd Prevathon 0.43SC 14.0 fl oz 0.00 0.08 (91)fgh 89ab 95a-d 0.46d Warrior II 2.08CS 1.92 fl oz 0.00 0.46 (51)cd 59de 76fg 1.96c Untreated check – 0.01 0.94 (−)ab 26fg 38h 5.88a NS Treatment/formulation Rate per acre Mean number larvae/ear Marketable ears (%) Total damaged kernels/eare Total ECBa Total CEWb (% control) Fresh marketc Processingd Coragen 1.67SC 5.0 fl oz 0.00 0.06 (94)gh 95a 96ab 0.24d Coragen 1.67SC 3.0 fl oz 0.00 0.05 (95)h 94a 95abc 0.36d Coragen 1.67SC + Preference 3.0 fl oz + 0.25% v/v 0.00 0.13 (86)fgh 85bc 89b-e 0.90d Coragen 1.67SC + AG16134 3.0 fl oz + 0.25% v/v 0.00 0.08 (91)fgh 88b 98a 0.63d Coragen 1.67SC + AG17047 3.0 fl oz + 0.25% v/v 0.00 0.16 (83)ef 81bc 88c-f 1.03cd Coragen 1.67SC + Interlock 3.0 fl oz + 2.0 oz 0.00 0.11 (88)e-h 84bc 89b-f 1.21cd Coragen 1.67SC + AG16134 + Interlock 3.0 fl oz + 0.25% v/v + 2.0 fl oz 0.00 0.11 (88)fgh 84bc 94a-d 1.10cd Coragen 1.67SC + AccuDrop 3.0 fl oz + 3.0 fl oz 0.00 0.11 (88)fgh 83bc 93a-d 1.23cd Coragen 1.67SC + AccuDrop + AG16134 3.0 fl oz + 3.0 fl oz + 0.25% v/v 0.00 0.14 (85)efg 83bc 91a-d 0.65d Coragen 1.67SC + Masterlock 3.0 fl oz + 6.4 fl oz 0.00 0.13 (86)efg 85bc 91a-d 0.69d Steward 1.25EC 6.0 fl oz 0.00 0.99 (−5)a 18g 44h 5.33a Steward 1.25EC 10.0 fl oz 0.00 0.65 (31)bc 43ef 58gh 3.51b Brigade 2EC 5.0 fl oz 0.00 0.14 (85)efg 81bc 86def 0.95cd Hero 1.24EC 5.0 fl oz 0.00 0.26 (72)de 73cd 78efg 1.10cd Prevathon 0.43SC 14.0 fl oz 0.00 0.08 (91)fgh 89ab 95a-d 0.46d Warrior II 2.08CS 1.92 fl oz 0.00 0.46 (51)cd 59de 76fg 1.96c Untreated check – 0.01 0.94 (−)ab 26fg 38h 5.88a NS Means within columns followed by the same letter are not significantly different (P > 0.05), Protected Least significant difference Test (LSD). Mean percentage of marketable ears for fresh market and processing were transformed using the arcsine transformation to obtain mean separations using LSD (P = 0.05). Insect counts were transformed using the square root transformation to obtain mean separations using LSD (P = 0.05); untransformed means are presented. NS = not significant. a Includes all ECB instars in the husk, silk, tip, side, butt, or shank of the ear. b Includes all CEW instars in the silk, tip, side, or butt of the ear. c Percentage of ears with no kernel damage or larvae present. d Percentage of ears with only small larvae (1–2 instar ECB and/or 1–2 instar CEW) and/or damage limited to the tip; no damage or larvae on the side or butt of the ear. e Total kernels damaged/ear in the tip, side, or butt by ECB and/or CEW. Open in new tab This research was supported by industry gifts of pesticide and/or research funding from Winfield United, FMC Corp., and Syngenta Crop Protection. © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Hesler, Louis, S;Beckendorf, Eric, A;Taliercio,, Earl

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz078

Soybean | Glycine max Soybean aphid (SA) | Aphis glycines Matsumura Uncultivated, or wild-type, soybean has many useful traits that may be incorporated into modern soybean cultivars to improve grain yield. One useful trait found in some wild soybean accessions is resistance to SA. The use of wild soybean to breed resistant soybean cultivars may ultimately limit yield loss from SA. The goal of this study was to evaluate resistance against SA among a set of select wild soybean accessions having a range of maturity groups. Wild soybean accessions were evaluated against two virulent colonies of SA. Evaluations consisted of five free-choice tests per colony run separately in growth chambers (Conviron, CMP4030,Winnipeg, Canada; 16:8 [L:D] h photoperiod at 24:18°C, respectively) at the North Central Agricultural Research Laboratory (NCARL), Brookings, SD. The first colony, ‘Volga16’, was started as a single female from SA collected on soybean plants with both the Rag1 and Rag2 SA-resistance genes near Volga, SD, in 2016. It was considered to be SA biotype 4 and reared on soybean cultivar ‘LD12R12-15805Ra’ (Rag1+Rag2 pyramid; University of Illinois, Urbana-Champaign, IL). A second colony, ‘Accrue’, was established with SA originally obtained in Ohio from SA-susceptible soybean plants and maintained initially as an avirulent colony at Ohio State University, Wooster, OH, with a subset of individuals transferred to and maintained at South Dakota State University (SDSU), Brookings, SD. A subgroup of individuals from the SDSU colony was used to establish a colony at NCARL in 2018, which was reared on the aphid-susceptible cultivar, ‘LD12-15838R’ (University of Illinois, Urbana-Champaign, IL). Although initially established as an avirulent SA colony in Ohio, testing at NCARL showed that the colony had accrued a majority of SA virulent to soybeans with either Rag1 or Rag2 individually but not to plants with both Rag1 and Rag2. The test accessions were plant introduction (PI) lines of wild soybean obtained from the USDA-ARS Soybean and Nitrogen Fixation Research Unit, Raleigh, NC, and the Soybean Germplasm Collection, National Soybean Research Center, Urbana, IL. Altogether, 70 test accessions were screened against the Volga16 colony and 72 test accessions against the Accrue colony. A total of 65 accessions was tested in common, but not all accessions could be tested against both colonies because of limited seed quantities and differential germination among tests. Accessions for the free-choice tests were prepared by placing two seeds of a particular PI line into an 8.5-cm square plastic pot filled with a 2:1:1 mixture of soil, vermiculite, and peat moss. Ten to 12 d after planting, pots were thinned to one seedling each by selecting for similar seedling sizes among PI lines, and the soil surface was then covered with a ca. 2.5-cm layer of sand. Two weeks after planting, PI lines were placed into a plastic tray that held 18 of the 8.5-cm square pots. Tests used six to eight replicate trays that each consisted of 14 PI lines, a susceptible check (PI 522212 B), a SA-resistant check (PI 549046), and two aphid-source plants. Tests 1 and 2 with the Accrue colony did not have a susceptible check due to poor germination of PI 522212 B. Each source plant was a 4-wk-old ‘IA2104’ soybean plant (Iowa State University, Ames, IA) that had about 250 SA from one of the two colonies for each respective set of free-choice tests. Source plants were placed at one of two foci in each tray equidistant from immediately surrounding PI lines and checks to facilitate even dispersal of aphids. In all tests, source plants were clipped at soil level at the start of each test to induce wilting and subsequent SA dispersal to test plants, and the clipped stem of the source plants was inserted upright into the soil. At 14 DAPE, PI lines in the second trifoliolate leaf stage (V2 stage) were given a common rating by two researchers, based on a rating scale that progressed from 1 = 0 to 50, 2 = 51 to 100, 3 = 101 to 150, 4 = 151 to 200, 5 = 201 to 250, and 6 with >250 SA per test plant. Infestation ratings were ranked among the test plants within each free-choice test, with ties assigned a midpoint value based on the ranking span for plants of equal rating. Rankings were analyzed for variation by PI line using an ANOVA-like nonparametric test to accommodate ranks (α = 0.05). The LSMEANS option was used to separate rankings among PI lines. Mean rankings ± SE and medians of infestation rantings are reported for each test. A PI line was characterized as resistant if its mean ranking did not differ from that of the resistant check and had a mean infestation rating < 3. Mean rankings of infestation levels varied significantly (P < 0.05) among accessions in each test with the Volga 16 colony (Table 1). In test 1, PI 597458 C and PI 407191wf had mean rankings that did not differ significantly from the control (PI 549046) and mean infestation ratings < 3. Other tests with Volgs16 SA had at least one accession that did not different significantly in mean rankings from the resistant check, but these and the remaining accessions all had mean ratings that were ≥ 3. Table 1. For each test, mean rankings followed by the same letter do not differ significantly (P > 0.05). Bold text indicates resistant check and italicized text indicates susceptible check. *Infestation ratings ranged from 1 (1–50 aphids per plant) to 6 (> 250 aphids per plant). †The suffix ‘wf’ denotes a within-accession selection for the white flower phenotype. Open in new tab Table 1. For each test, mean rankings followed by the same letter do not differ significantly (P > 0.05). Bold text indicates resistant check and italicized text indicates susceptible check. *Infestation ratings ranged from 1 (1–50 aphids per plant) to 6 (> 250 aphids per plant). †The suffix ‘wf’ denotes a within-accession selection for the white flower phenotype. Open in new tab Mean rankings of infestation levels also varied significantly (P < 0.05) among accessions tested against the Accrue colony (Table 2). In test 1, PI 407175 had a mean infestation ranking that did not differ from that of the resistant check, PI 549046. In test 2, PI 407190 and PI 407420 had mean infestation rankings that did not differ significantly from that of the resistant check, PI 549046, and had mean ratings < 3, whereas PI 549046 had a mean rating of 4.3. In test 3, PI 507624 had a mean infestation ranking that did not differ significantly from PI 549046 and a mean infestation rating < 3. In test 4, PI 562558 had a mean infestation ranking that did not differ significantly from PI 549046 and a mean infestation rating < 3. The remaining accessions in tests 1 through 4 had mean infestation rankings ≥ 3. All accessions in test 5 except PI 549046 had mean infestation ratings ≥ 3. Table 2. For each test, mean rankings followed by the same letter do not differ significantly (P > 0.05). Bold text indicates resistant check and italicized text indicates susceptible check. Susceptible check not included in tests 1 and 2 due to poor germination. *Infestation ratings ranged from 1 (1–50 aphids per plant) to 6 (> 250 aphids per plant). †The suffix ‘wf’ denotes a within-accession selection for the white flower phenotype. ‡Suffix denotes a subset of this accession used previously in agronomic studies. Open in new tab Table 2. For each test, mean rankings followed by the same letter do not differ significantly (P > 0.05). Bold text indicates resistant check and italicized text indicates susceptible check. Susceptible check not included in tests 1 and 2 due to poor germination. *Infestation ratings ranged from 1 (1–50 aphids per plant) to 6 (> 250 aphids per plant). †The suffix ‘wf’ denotes a within-accession selection for the white flower phenotype. ‡Suffix denotes a subset of this accession used previously in agronomic studies. Open in new tab This research was supported by base funding from USDA CRIS Projects 3080-21220-006-00D and 6070-21220-069-00D. Published by Oxford University Press on behalf of Entomological Society of America 2019. This work is written by (a) US Government employee(s) and is in the public domain in the US. This Open Access article contains public sector information licensed under the Open Government Licence v2.0 (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/2/).

McManus, Bradley, L;Fuller, Billy, W

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz039

Corn (hybrid, maize, sweet) | Zea mays Northern corn rootworm (NCR) | Diabrotica barberi Smith and Lawrence, Western corn rootworm (WCR) | Diabrotica virgifera virgifera LeConte thiamethoxam Corn rootworm (NCR/WCR) management efficacy trials were conducted to evaluate seed treatment rates near Cavour and Coleman, South Dakota. Experimental plots were arranged in an RCBD with four replications. Plot size was four rows by 45 ft at Cavour and by 48 ft at Coleman spaced 30 inches apart. Plots were planted on 9 May at Cavour and on 11 and 12 May Coleman.The nonrootworm-resistant hybrid evaluated in this efficacy trial was 2017 ‘Syngenta/NorthrupKing N31H3220EZ4’. Corn seed was planted at a rate of 31,000 kernels per acre at both locations. Plant stand counts and lodging data were collected from the center 2 rows of each plot. Stand was determined by counting the number of plants in 17.4 ft of row (1/1,000th of an acre) and lodging data were the total number of plants in the row divided by the ones that were at a 30-degree or greater angle. Root rating means were derived from six roots at growth stage R1 and dug randomly from the two outer rows that were washed and rated using the Oleson 0 to 3 root injury rating scale. Yield assessments in bushels per acre were taken from the center two rows (Cavour harvested 23 Oct 2017, Colman harvested 12 Oct 2017). Yield and root rating data were analyzed using PROC MIXED/PDIFF option with Saxton’s lettering macro in SAS (version 9.2). Root injury from corn rootworm in the untreated check exceeded ~0.25 EIL at both locations (Cavour 0.83 and Colman 1.23). There were no significant differences among treatments for corn rootworm root rating, plant stand, percent lodging at harvest, or yield at either location (Table 1). The addition of Thiamethoxam (Cruiser 5FS) at 0.25, 0.50, or 1.25 mg (ai)/seed did not result in a significant reduction in root injury at either location. At the Cavour site, the untreated check had the lowest root injury score. The untreated and Cruiser 0.5 mg (ai)/seed-treated plots showed more roots pruned than plots planted with seed treated with Cruiser at the 0.25 or 1.25 rates at the Colman location. The untreated plots did not have the fewest bu/acre at the locations. The addition of a Cruiser seed treatment at any of the three rates tested did not result in an increased root protection or yield at our research sites. Percent lodging at Cavour was >70% across all treatments, which made harvest difficult. Conversely, 6.5 to 12.3% lodging per row was observed at the Colman site. Results from this study indicated that the addition of a seed-applied insecticide, even at increased rates, might not result in increased root protection from rootworm larval feeding or a yield increase. Table 1. Treatment/formulation Rate mg (ai/)seed Cavour Coleman Root rating Yield (bu/acre) % Lodging Stand 28 dat plants/acre Root rating Yield (bu/acre) % Lodging Stand 28 DAT plants/acre Untreated check – 0.83a 50.7a 87.5a 25,500a 1.23a 168.5a 12.3a 28,000a Cruiser 5FS 0.25 1.50a 46.7a 73.8a 28,000a 0.87a 158.9a 6.5a 27,100a Cruiser 5FS 0.50 1.18a 57.7a 79.5a 28,300a 1.25a 171.6a 7.7a 27,600a Cruiser 5FS 1.25 1.23a 48.6a 77.5a 27,000a 0.70a 182.2a 6.7a 28,000a P > F 0.9176 0.6431 0.8125 0.5458 0.3669 0.3708 0.6854 0.9121 Treatment/formulation Rate mg (ai/)seed Cavour Coleman Root rating Yield (bu/acre) % Lodging Stand 28 dat plants/acre Root rating Yield (bu/acre) % Lodging Stand 28 DAT plants/acre Untreated check – 0.83a 50.7a 87.5a 25,500a 1.23a 168.5a 12.3a 28,000a Cruiser 5FS 0.25 1.50a 46.7a 73.8a 28,000a 0.87a 158.9a 6.5a 27,100a Cruiser 5FS 0.50 1.18a 57.7a 79.5a 28,300a 1.25a 171.6a 7.7a 27,600a Cruiser 5FS 1.25 1.23a 48.6a 77.5a 27,000a 0.70a 182.2a 6.7a 28,000a P > F 0.9176 0.6431 0.8125 0.5458 0.3669 0.3708 0.6854 0.9121 Means within columns followed by the same letter are not significantly (P > 0.05) different using SAS, version 9.2 PROC MIXED/PDIFF option with Saxton’s lettering macro. Open in new tab Table 1. Treatment/formulation Rate mg (ai/)seed Cavour Coleman Root rating Yield (bu/acre) % Lodging Stand 28 dat plants/acre Root rating Yield (bu/acre) % Lodging Stand 28 DAT plants/acre Untreated check – 0.83a 50.7a 87.5a 25,500a 1.23a 168.5a 12.3a 28,000a Cruiser 5FS 0.25 1.50a 46.7a 73.8a 28,000a 0.87a 158.9a 6.5a 27,100a Cruiser 5FS 0.50 1.18a 57.7a 79.5a 28,300a 1.25a 171.6a 7.7a 27,600a Cruiser 5FS 1.25 1.23a 48.6a 77.5a 27,000a 0.70a 182.2a 6.7a 28,000a P > F 0.9176 0.6431 0.8125 0.5458 0.3669 0.3708 0.6854 0.9121 Treatment/formulation Rate mg (ai/)seed Cavour Coleman Root rating Yield (bu/acre) % Lodging Stand 28 dat plants/acre Root rating Yield (bu/acre) % Lodging Stand 28 DAT plants/acre Untreated check – 0.83a 50.7a 87.5a 25,500a 1.23a 168.5a 12.3a 28,000a Cruiser 5FS 0.25 1.50a 46.7a 73.8a 28,000a 0.87a 158.9a 6.5a 27,100a Cruiser 5FS 0.50 1.18a 57.7a 79.5a 28,300a 1.25a 171.6a 7.7a 27,600a Cruiser 5FS 1.25 1.23a 48.6a 77.5a 27,000a 0.70a 182.2a 6.7a 28,000a P > F 0.9176 0.6431 0.8125 0.5458 0.3669 0.3708 0.6854 0.9121 Means within columns followed by the same letter are not significantly (P > 0.05) different using SAS, version 9.2 PROC MIXED/PDIFF option with Saxton’s lettering macro. Open in new tab A portion of this research was supported by USDA–NIFA and industry funds. © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]

Addesso, Karla, M;O’Neal, Paul, A

2019 Arthropod Management Tests

doi: 10.1093/amt/tsz010

Crapemyrtle | Lagerstroemia indica Crapemyrtle aphid | Sarucallis kahawaluokalani (Kirkaldy) flupyradifurone, flonicamid, spirotetramat This study tested the efficacy of preventative drench and foliar insecticide treatments for protecting ‘Hopi’ crape myrtle, Lagerstroemia indica L. x fauriei Koehne, from crapemyrtle aphid, Sarucallis kahawaluokalani (Kirkaldy). The study was performed in a greenhouse at the Tennessee State University Nursery Research Center, McMinnville, TN. In Mar 2017, rooted cuttings were established in 1-gal containers in pine bark mulch media. Plants were fertilized with the medium rate of 18-6-12 Osmocote Classic and maintained with drip-line irrigation. Crape myrtles were periodically sprayed with horticultural oil as a low-residual measure to manage arthropod pests. Experimental plants were assigned to the chemical treatments in Table 1. The foliar Altus treatment was sprayed to runoff with a backpack sprayer (Solo, Newport News, VA) and plants in the drench treatments received 12.8 oz of solution (10% container volume) applied across the media surface. The experimental plants were arranged on a greenhouse bench in an RCB design with six replicates. Twenty-four hours after chemical applications, a leaf disc with 10 immature aphids was placed in the canopy of each experimental plant. At 0, 7, 14, 21, 28, 35, and 42 DAT, the newest, fully expanded leaf was sampled from the central leader of each experimental plant and aphid adults and immatures were counted. Adult and immature counts were analyzed independently with a generalized linear model fitted to a negative binomial distribution (PROC GENMOD, SAS Institute Inc.). Post hoc tests were performed with a Tukey–Kramer test with P values adjusted for multiple comparisons. Table 1. Treatment/formulation Application rate Dose/plant Application method Untreated check  Aria WG 2.1 oz/100 gal 12.8 oz Drench  Kontos SC 3.4 oz/100 gal 12.8 oz Drench  Altus SL 2.8 oz/100 gal 12.8 oz Drench  Altus SL 3.7 oz/100 gal 12.8 oz Drench  Altus SL 14 oz/100 gal To runoff Foliar Treatment/formulation Application rate Dose/plant Application method Untreated check  Aria WG 2.1 oz/100 gal 12.8 oz Drench  Kontos SC 3.4 oz/100 gal 12.8 oz Drench  Altus SL 2.8 oz/100 gal 12.8 oz Drench  Altus SL 3.7 oz/100 gal 12.8 oz Drench  Altus SL 14 oz/100 gal To runoff Foliar Open in new tab Table 1. Treatment/formulation Application rate Dose/plant Application method Untreated check  Aria WG 2.1 oz/100 gal 12.8 oz Drench  Kontos SC 3.4 oz/100 gal 12.8 oz Drench  Altus SL 2.8 oz/100 gal 12.8 oz Drench  Altus SL 3.7 oz/100 gal 12.8 oz Drench  Altus SL 14 oz/100 gal To runoff Foliar Treatment/formulation Application rate Dose/plant Application method Untreated check  Aria WG 2.1 oz/100 gal 12.8 oz Drench  Kontos SC 3.4 oz/100 gal 12.8 oz Drench  Altus SL 2.8 oz/100 gal 12.8 oz Drench  Altus SL 3.7 oz/100 gal 12.8 oz Drench  Altus SL 14 oz/100 gal To runoff Foliar Open in new tab Low numbers of adult (Table 2) and immature (Table 3) aphids were found on the experimental plants at 0 DAT and no significant difference between any of the treatments was observed. Adult aphids were not observed on any of the treatments at 7 DAT. From 14 DAT through 42 DAT, the Aria drench and all three Altus treatments had significantly fewer adult aphids than the check. The Kontos drench treatment had fewer adult aphids than the check at 14, 21, and 28 DAT but was equal to the check at 35 and 42 DAT. All chemical treatments had significantly fewer immature aphids than the check at 0, 7, 14, 21, 28, and 35 DAT. The Kontos drench treatment had the same number of immatures as the untreated check at 42 DAT. Table 2. Treatment/formulation Application Adult aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.17 0 0.83a 2.33a 6.67a 3.17a 4.33a Aria Drench 0.33 0 0b 0c 0b 0.33c 0.17c Altus Low-rate drench 0.33 0 0b 0.17c 0.83b 0.33c 0.67c Altus High-rate drench 0 0 0b 0c 0b 0.5bc 0.83bc Altus Foliar spray 0.17 0 0.17b 0c 0.17b 0c 0.5c Kontos Drench 0.33 0 0b 1.17b 1.33b 1.83ab 3.17ab P value NS NS 0.01 <0.0001 <0.0001 0.001 0.01 Treatment/formulation Application Adult aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.17 0 0.83a 2.33a 6.67a 3.17a 4.33a Aria Drench 0.33 0 0b 0c 0b 0.33c 0.17c Altus Low-rate drench 0.33 0 0b 0.17c 0.83b 0.33c 0.67c Altus High-rate drench 0 0 0b 0c 0b 0.5bc 0.83bc Altus Foliar spray 0.17 0 0.17b 0c 0.17b 0c 0.5c Kontos Drench 0.33 0 0b 1.17b 1.33b 1.83ab 3.17ab P value NS NS 0.01 <0.0001 <0.0001 0.001 0.01 Lowercase letters indicate that the treatment is statistically different from Tukey–Kramer test at P < 0.05. Open in new tab Table 2. Treatment/formulation Application Adult aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.17 0 0.83a 2.33a 6.67a 3.17a 4.33a Aria Drench 0.33 0 0b 0c 0b 0.33c 0.17c Altus Low-rate drench 0.33 0 0b 0.17c 0.83b 0.33c 0.67c Altus High-rate drench 0 0 0b 0c 0b 0.5bc 0.83bc Altus Foliar spray 0.17 0 0.17b 0c 0.17b 0c 0.5c Kontos Drench 0.33 0 0b 1.17b 1.33b 1.83ab 3.17ab P value NS NS 0.01 <0.0001 <0.0001 0.001 0.01 Treatment/formulation Application Adult aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.17 0 0.83a 2.33a 6.67a 3.17a 4.33a Aria Drench 0.33 0 0b 0c 0b 0.33c 0.17c Altus Low-rate drench 0.33 0 0b 0.17c 0.83b 0.33c 0.67c Altus High-rate drench 0 0 0b 0c 0b 0.5bc 0.83bc Altus Foliar spray 0.17 0 0.17b 0c 0.17b 0c 0.5c Kontos Drench 0.33 0 0b 1.17b 1.33b 1.83ab 3.17ab P value NS NS 0.01 <0.0001 <0.0001 0.001 0.01 Lowercase letters indicate that the treatment is statistically different from Tukey–Kramer test at P < 0.05. Open in new tab Table 3. Treatment/formulation Application Immature aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.33 0.33a 15.68a 43.67a 52.5a 52a 42.33a Aria Drench 4.83 0b 0b 0.33b 0.33b 0.5b 0.33b Altus Low rate drench 6.17 0b 0.17b 0.33b 0.83b 0.33b 0.17b Altus High rate drench 0 0b 0b 0.50b 0b 0.67b 0b Altus Foliar spray 2 0b 0b 0.17b 0.17b 0b 0b Kontos Drench 8.83 0b 0b 5.17b 8.5b 11.5b 30a P value NS 0.03 0.0006 <0.0001 <0.0001 <0.0001 <0.0001 Treatment/formulation Application Immature aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.33 0.33a 15.68a 43.67a 52.5a 52a 42.33a Aria Drench 4.83 0b 0b 0.33b 0.33b 0.5b 0.33b Altus Low rate drench 6.17 0b 0.17b 0.33b 0.83b 0.33b 0.17b Altus High rate drench 0 0b 0b 0.50b 0b 0.67b 0b Altus Foliar spray 2 0b 0b 0.17b 0.17b 0b 0b Kontos Drench 8.83 0b 0b 5.17b 8.5b 11.5b 30a P value NS 0.03 0.0006 <0.0001 <0.0001 <0.0001 <0.0001 Lowercase letters indicate that the treatment is statistically different from Tukey–Kramer test at P < 0.05. Open in new tab Table 3. Treatment/formulation Application Immature aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.33 0.33a 15.68a 43.67a 52.5a 52a 42.33a Aria Drench 4.83 0b 0b 0.33b 0.33b 0.5b 0.33b Altus Low rate drench 6.17 0b 0.17b 0.33b 0.83b 0.33b 0.17b Altus High rate drench 0 0b 0b 0.50b 0b 0.67b 0b Altus Foliar spray 2 0b 0b 0.17b 0.17b 0b 0b Kontos Drench 8.83 0b 0b 5.17b 8.5b 11.5b 30a P value NS 0.03 0.0006 <0.0001 <0.0001 <0.0001 <0.0001 Treatment/formulation Application Immature aphids per leaf 0 DAT 7 DAT 14 DAT 21 DAT 28 DAT 35 DAT 42 DAT Untreated 0.33 0.33a 15.68a 43.67a 52.5a 52a 42.33a Aria Drench 4.83 0b 0b 0.33b 0.33b 0.5b 0.33b Altus Low rate drench 6.17 0b 0.17b 0.33b 0.83b 0.33b 0.17b Altus High rate drench 0 0b 0b 0.50b 0b 0.67b 0b Altus Foliar spray 2 0b 0b 0.17b 0.17b 0b 0b Kontos Drench 8.83 0b 0b 5.17b 8.5b 11.5b 30a P value NS 0.03 0.0006 <0.0001 <0.0001 <0.0001 <0.0001 Lowercase letters indicate that the treatment is statistically different from Tukey–Kramer test at P < 0.05. Open in new tab This research was supported in part by funding and materials provided by Bayer. © The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected]