Euphytica

Souza, Analu Cruz; Souza, Margarete Magalhães; Silva, Gonçalo Santos; Lavinscky, Manuella Palmeira; de Oliveira Souza, Viviane; de Oliveira Freitas, Jôsie Cloviane

doi: 10.1007/s10681-022-03110-zpmid: N/A

Interspecific hybrids can be studied using methodologies in which the male gamete with high reproduction potential, viability, and fertility is prioritized. Passiflora species, with lush, showy, and exotic colors, have great potential for the ornamental plant market. In addition, artificial Passiflora hybrids were developed without many difficulties because of weak reproductive barriers. Thus, meiotic and post-meiotic behaviors were analyzed with 2% acetic carmine staining. Confirmation of interspecific hybridization was performed using SSR markers and GISH technique was used to detect genomic differentiation. The pollen viability of the parental and hybrids genotypes was tested using Alexander`s solution, fluorescein diacetate and in vitro germination tests were performed using culture medium. The meiotic behavior was regular and displayed haploid number n = 9 with nine bivalent (II) chromosomal, and pairing in 90% of the cells in diakinesis. There was a significant difference (p < 0.05) in terminal and interstitial chiasma frequencies. Meiotic irregularities observed were as follows: early and/or delayed chromosomes, disorientation of spindle fibers, transverse spindles, tripolar spindles, and asynchrony; and consequently irregular post-meiotic products were observed: monads, dyads, triads, and polyads. GISH was used in the interspecific hybrids and pairing between homeologous chromosomes, and bivalent and tetravalent formation were observed. From this study, we could conclude that hybrid genotypes are fertile and pollen grains are viable and can be used in breeding programs.

Aliyu, Aminu; Ishiyaku, Mohammad Faguji; Offei, Samuel Kwame; Asante, Isaac Kolo; Eleblu, John Saviour Yaw; Aliyu, Ramatu Enehezeyi

doi: 10.1007/s10681-022-03140-7pmid: N/A

Cowpea is an important leguminous crop that serve as source of food to man and as fodder to livestock. Despite the economic importance of cowpea, its production is limited by biotic and abiotic stress. The most important biotic stress affecting cowpea are insect pests amongst which are Aphids (Aphis crassivora L.) that can wipe 80–100% of cowpea farm. The insects can also transmit virus diseases including cowpea borne mosaic virus (CBMV) that drastically reduce cowpea yield in farmer’s field. Several methods have been adopted by small holder farmers to control the menace of aphids in their field. Such methods include mechanical, chemical, biological, cultural and integrated pest management. However, these control strategies expensive, unsustainable and unaffordable to resource-poor farmers. The most sustainable, cost-effective, environmentally friendly and viable measure of controlling A. crassivora is the development of host plant resistance which does not require much efforts by farmers. Conventional, molecular and mutation breeding approaches were employed to develop cowpea varieties with resistance to aphid infestation for enhanced cowpea production. This review paper ensured sufficient documentation of information/progresses on the breeding efforts by researchers to enhance cowpea productivity. It will also serve as reference for researchers to determine effective breeding strategies to control the effects of aphids in farmer’s field.

Çetin, Necati; Ozaktan, Hamdi; Uzun, Satı; Uzun, Oguzhan; Ciftci, Cemalettin Yasar

doi: 10.1007/s10681-022-03150-5pmid: N/A

Chickpea is an important edible legume that can be grown in rain fed conditions. Image analysis and machine learning could be used for rapid and non-destructive determination of seed physical attributes and such techniques yield objective, accurate and reliable results. In this study, size, shape, and area attributes of 26 different chickpea cultivars were determined by image processing method, and color properties were determined by chromametric method, and machine learning algorithms (Multilayer Perceptron-MLP, Random Forest-RF, Support Vector Regression-SVR, and k-Nearest Neighbor-kNN, were used for mass prediction of chickpea seeds. Ilgaz and Çakır cultivars had the highest size and shape values, while İzmir and Sezenbey cultivars had the highest color attributes. Compactness (in horizontal orientation) had a positive correlation with the equivalent diameter (in vertical orientation) and elongation (in vertical orientation) (r = 0.99 for both parameters). Besides, a* had a high correlation with b* (r = 0.97). According to Euclidean distances, Akça–İnci and Damla–Işık cultivars were identified as the closest cultivars in terms of physical attributes. In PCA analysis, PC1 and PC2 explained 73.17% of the total variation. The PC1 included length, geometric mean diameter, volume and surface area, and the PC2 included roundness (in horizontal orientation), thickness, elongation (in horizontal orientation) and sphericity. RF and ML had successful results with the values of 0.8054 and 0.8043 for train-test split, and 0.8231 and 0.8142 for k-fold cross validation, respectively. Present findings revealed that texture image processing and machine learning could be used as an effective and inexpensive discrimination tool for chickpea seeds.

Chemonges, Martin; Herselman, Liezel; Pretorius, Zacharias A.; Rouse, Matthew N.; Marè, Ansori; Boshoff, Willem H. P.

doi: 10.1007/s10681-022-03143-4pmid: N/A

Several South African winter wheat cultivars express all-stage resistance to local races of Puccinia graminis f. sp. tritici (Pgt). To study the inheritance of resistance, cultivars Komati, Koonap, Limpopo and SST 387 were crossed with the stem rust susceptible Line 37-07. Segregation of reaction to Pgt race PTKST in each of the four F2 populations indicated the presence of a single dominant resistance gene. Allelism tests among the resistant parents indicated that the same gene, alleles of the same gene, or closely linked genes were involved. The resistance gene(s) mapped to the short arm of chromosome 6D and was flanked by SSR markers barc183 and wms4862. The four cultivars tested negative using single nucleotide polymorphism (SNP) markers linked to Sr42, SrTmp and SrCad also located on chromosome arm 6DS. Allelism tests between the resistant cultivars and Norin 40 (Sr42) and CnsSrTmp (SrTmp) also suggested common genes for resistance. Multi-race phenotyping ruled out involvement of Sr42 and SrCad in all tested cultivars. The available evidence suggested the presence of previously uncharacterised gene(s) or alleles of Sr42, SrTmp or SrCad in all four cultivars. SNP marker BS00085937 and SSR markers psp3200 and wms4862 were 90.9–92.7% effective in predicting stem rust resistance among 55 South African genotypes and could be useful for marker-assisted selection.

Yao, Xindong; Xu, Jiang-yuan; Liu, Zhang-xiong; Pachner, Martin; Molin, Eva Maria; Rittler, Leopold; Hahn, Volker; Leiser, Willmar; Gu, Yong-zhe; Lu, Yu-qing; Qiu, Li-juan; Vollmann, Johann

doi: 10.1007/s10681-022-03147-0pmid: N/A

Soybean (Glycine max [L.] Merr.) is a legume crop important for global food security due to supplying high-quality vegetable protein and oil. China is the origin and rich center of soybean genetic diversity represented by numerous landraces and other genetic resources. During the nineteenth and twentieth centuries, world-wide dissemination of plant introductions laid the foundation of modern soybean production. Due to selection for regional adaptation, present-day elite soybean cultivars do have a comparatively narrow genetic base. However, as genetic variation is the major component of future breeding progress, diversity of early maturity Chinese and European elite soybeans was comparatively analyzed using a high-throughput functional SNP array and an SSR marker set. Results revealed a clear differentiation between Chinese and European elite cultivars, and the level of genetic diversity was similar between the two populations. Both in Chinese and European cultivars, unique SSR alleles were found which indicates that selection for specific adaptation can preserve genetic variation. The European population was markedly structured by maturity groups which was less clear in the Chinese population. Structure analysis indicated that European cultivars are based on two major ancestral lines, whereas Chinese elite soybean cultivars trace back to more ancestral lines pointing to the rich natural soybean diversity of China. The results confirm that long-term selection under divergent environmental and agronomic conditions can produce specific diversity which could potentially be utilized for future enhancing both Chinese and European soybean breeding.

Ikegaya, Tomohito; Shirasawa, Kenta; Fujino, Kenji

doi: 10.1007/s10681-022-03133-6pmid: N/A

Crop breeding programs can improve traits associated with desirable phenotypic characteristics to different local environmental conditions. In rice, such improvements were achieved depending on genetic diversity among local populations. Here, we examined whether differences in traits of elite varieties are due to genetic differences and from what the genetic differences are derived. Previously, we identified one quantitative trait locus (QTLs) associated with heading date, i.e., the quantitative trait locus for days to heading on chromosome 3 (qDTH3). Using 592 plants of the F2 generation, fine mapping narrowed the qDTH3 locus down to a 158-kb region of the corresponding rice reference genome. Based on the genome sequences of a 656-kb region including the qDTH3 locus among four Oryza species collections, we propose the historic evolutionary process of cultivated rice, considering nucleotide polymorphisms and intrapopulation recombination. Phenotypic differences in qDTH3 in elite varieties may be derived from a different lineage split from the ancestor.

Mohammadi, Reza; Jafarzadeh, Jafar; Armion, Mohammad; Poursiahbidi, Mohammad Mehdi; Hatamzadeh, Hossein; Khalilzadeh, Gholam Reza

doi: 10.1007/s10681-022-03138-1pmid: N/A

Mega-environment (ME) investigation and genotype evaluation are among the most important objectives of multi-environment trials. This study aims to investigate the possible existence of meaningful mega-environments and identify high-yielding and stable genotypes for rainfed durum wheat-growing regions. The GGE (genotypic main effect plus genotype-by-environment interaction) and GGL (genotypic main effect plus genotype-by-location interaction) biplots analyses were applied to durum wheat grain yield data from multi-year trials conducted at six locations differing in climatic conditions across Iran. Yearly multi-location analysis of variance for grain yield revealed that the location was the main source of variation and captured for 78.5–89.8% of total variation and the GL interaction, depending on year, was greater 2.8–4.4 times than genotype effect alone. The collective analysis of yearly GGL biplots revealed repeatable locations grouping across years and showed that the durum wheat growing region can be divided into four MEs: the western ME represented by the moderate cold location, southern-west ME represented by moderate warm location, western-north ME and eastern-north ME both represented for cold locations. The results suggest that durum wheat yield trials should be conducted and genotype recommendation be made according to each ME. The evaluation of genotypes for mean yield and stability performance per each ME, recommended the breeding line G14 for each both western and western-north MEs, breeding line G10 for southern-west ME and breeding line G3 for eastern-north ME. Based on the factorial regression analysis, climatic variables of monthly rainfall in March (17.5%), May (9.5%), June (7.9%), April (6.8%), cumulative rainfall (12.5%), and average temperature of January (6.6%) significantly (P < 0.01) affected genotypes performance and contributed to 60.8% of total GE variation. The results confirmed four different mega-environments in durum wheat yield trials, suggest genotype recommendation should be made according to each mega-environment.

Su, Jiangshuo; Yang, Yingnan; Zhang, Xuefeng; Li, Zhaoqing; Lu, Zhaowen; Jia, Feifei; Wang, Haibin; Guan, Zhiyong; Fang, Weimin; Chen, Fadi; Zhang, Fei

doi: 10.1007/s10681-022-03148-zpmid: N/A

Waterlogging stress is one of the major abiotic stresses that negatively affect chrysanthemum (Chrysanthemum morifolium Ramat.) growth and development, thus reducing its productivity. Therefore, there is a need to develop waterlogging-tolerant chrysanthemum germplasms to deal with this problem, and the identification of tolerant wild chrysanthemum (C. indicum) is relevant to the improvement of cultivated chrysanthemum targeting resistance traits. In the current study, we aimed to evaluate the waterlogging tolerance of wild chrysanthemums by using the membership function value of waterlogging (MFVW) and multiple regression analysis based on seven morphological traits related to waterlogging tolerance. By MFVW, the investigated 19 C. indicum accessions were classified into five grades: one waterlogging-tolerant accession, 12 moderately waterlogging-tolerant accessions, and every two accessions for highly waterlogging-tolerant, waterlogging-sensitive, and highly waterlogging-sensitive types, respectively. Of all traits tested, Score, shoot fresh weight, and root fresh weight are considered reliable indicators, exhibiting a higher correlation with waterlogging tolerance. The mathematical evaluation model of waterlogging tolerance based on MFVW proved robust by comparing the observed MFVW and predicted Y values in two interspecific segregating F1 populations derived from C. indicum and C. japonense, with average R2 ranging between 0.957 and 0.982. The method established in the current study provides a reference for the rapid identification and accurate prediction of waterlogging tolerance in chrysanthemum germplasms, and the highly waterlogging-tolerant wild chrysanthemum germplasms identified herein help widen the genetic base for breeding chrysanthemum cultivars with desirable waterlogging tolerance.

Dutta, Pradipta; Hazra, Pranab; Hazra, Soham; Maji, Anirban; Chattopadhyay, Arup

doi: 10.1007/s10681-022-03146-1pmid: N/A

Improvement of snap melon (Cucumis melo L. var. momordica (Roxb.) has been constrained by the lack of adequate information on genetic control of different fruit and quality characters. The study was conducted to determine gene action, heterosis and narrow sense heritability for 13 quantitative characters using 5 × 5 half diallel analysis. No interaction between genes was evident in controlling most characters suggesting the adequacy of additive-dominance model. Both additive and dominance components of genetic variance were significant in most characters however, dominance component was much higher in magnitude. Overwhelming response of over-dominance was evident for most traits. Symmetrical distribution of positive and negative alleles in parents was recorded for days to first male and female flower, and number of fruits per plant while, asymmetrical distribution was evident for 10 characters. Dominant alleles were more frequent for 11 characters while, recessive alleles were more frequent for fruit length and diameter. One gene group showing dominance was responsible for the inheritance of 11 characters; two gene groups controlled days to first male flower while, three gene groups conditioned number of fruits per plant. Narrow sense heritability for different characters was very low to medium (2.75–34.58%). Hybrid breeding can be used to improve fruit yield and quality in snap melon however, manifestation of heterosis was highly dependent on the parents and traits considered.

Bai, Jingyi; Chen, Bin; Qi, Meixia; Du, Heshan; Wang, Qian; Geng, Sansheng; Zhang, Xiaofen

doi: 10.1007/s10681-022-03100-1pmid: N/A

Microspore embryogenesis is widely used in plant breeding to obtain homozygous lines. It is an important way of obtaining haploids and it is valuable for QTL (Quantitative Trailt Locus) mapping and genetic research. We analyzed the microspore embryogenesis ability of 142 recombinant inbred lines (RIL) and mapped QTLs for microspore embryogenesis based on a genetic map constructed using specific-locus amplified fragment sequencing SLAF-seq technology. Results revealed that microspore embryogenesis ability in pepper is a quantitative character. Seven QTLs were detected on linkage groups LG2, LG6, LG8, LG11 and LG12. The peak logarithm of odds (LOD) score of the seven QTLs ranged from 3.51 to 6.66, and the range of phenotypic variation explained by a single QTL ranged from 4.76 to 18.30%. We identified a major QTL, Me2.2, located in the region of 116.5–118.5 cM on LG2; the corresponding physical segment was 166,621,667–167,038,758 bp, and 24 candidate genes were predicted in this region. Functional annotation indicated that these genes are closely related to the initiation of cell division, symmetrical or asymmetric cell division, and other life processes. The study laid a good foundation for further research on the mechanism of microspore embryogenesis.