Acta Physiologiae Plantarum

Shibata, Koichi; Abe, Shunnosuke; Davies, Eric

doi: 10.1007/s11738-001-0016-ypmid: 12238526

Partial amino acid sequences of a 49 kDa apyrase (ATP diphosphohydrolase, EC 3.6.1.5) from the cytoskeletal fraction of etiolated pea stems were used to derive oligonucleotide DNA primers to generate a cDNA fragment of pea apyrase mRNA by RT-PCR and these primers were used to screen a pea stem cDNA library. Two almost identical cDNAs differing in just 6 nucleotides within the coding regions were found, and these cDNA sequences were used to clone genomic fragments by PCR. Two nearly identical gene fragments containing 8 exons and 7 introns were obtained. One of them (H-type) encoded the mRNA sequence described by Hsieh et al. (1996) (DDBJ/EMBL/GenBank Z32743), while the other (S-type) differed by the same 6 nucleotides as the mRNAs, suggesting that these genes may be alleles. The six nucleotide differences between these two alleles were found solely in the first exon, and these mutation sites had two types of consensus sequences. These mRNAs were found with varying lengths of 3′ untranslated regions (3′-UTR). There are some similarities between the 3′-UTR of these mRNAs and those of actin and actin binding proteins in plants. The putative roles of the 3′-UTR and alternative polyadenylation sites are discussed in relation to their possible role in targeting the mRNAs to different subcellular compartments.

Mikuła, Anna; Rybczyński, Jan

doi: 10.1007/s11738-001-0017-xpmid: N/A

Experiments were carried out on three selected species of Gentiana genus: Gentiana cruciata (L.), G. pannonica (Scop.), and G. tibetica (King). Using MS medium supplemented with 2,4-D and kinetin a somatic embryogenesis system of plant regeneration was developed. Induction and intensity of somatic embryogenesis as the effect of integration of the following factors were studied, specifically: seedling pre-treatment (with and without GA3 treatment), light condition (light versus the dark), and type of explant (root, cotyledon and hypocotyl). Numerous significant differences between studied factors were observed and statistically proved.

Hayat, S.; Ahmad, A.; Hussain, A.; Mobin, M.

doi: 10.1007/s11738-001-0018-9pmid: N/A

An experiment was conducted under controlled conditions, in which grains of wheat (Triticum aestivum L. cv. Raj-3077) were soaked in 0, 1, 3 and 5 µM aqueous solutions of 28-homobrassinolide (HBR) for 4, 8 and 12 hours. The seedlings raised from the grains pre-treated with HBR possessed significantly higher leaf number, fresh and dry weight·plant−1, nitrate reductase (NR,E.C. 1.6.6.1) and carbonic anhydrase (CA, E.C. 4.2.1.1) activities on 25 and 35 days, after sowing. The soaking of the grains in 3 µM concentration for 8 or 12 hours produced the most vigorous seedlings.

Gupta, Anil; Singh, Jasvinder; Kaur, Narinder

doi: 10.1007/s11738-001-0019-8pmid: N/A

Accumulation of 60–70 % of biomass in turnip root takes place between 49–56 days after sowing. To understand the phenomenon of rapid sink filling, the activities of sucrose metabolising enzymes and carbohydrate composition in leaf blades, petiole and root of turnip from 42–66 days of growth were determined. An increase (2–3 folds) in glucose and fructose contents of roots accompanied by an increase in activities of acid and alkaline invertases was observed during rapid biomass accumulating phase of roots. The observed decrease in the activities of acid and alkaline invertases along with sucrose synthase (cleavage) in petiole during this period could facilitate unrestricted transport of sucrose from leaves to the roots. During active root filling period, a decrease in sucrose synthase (cleavage) and alkaline invertase activities was also observed in leaf blades. A rapid decline in the starch content of leaf blades was observed during the phase of rapid sink filling. These metabolic changes in the turnip plant led to increase in hexose content (35–37 %) of total dry biomass of roots at maturity. High hexose content of the roots appears to be due to high acid invertase activity of the root.

Menke-Milczarek, Izabela; Zimny, Janusz

doi: 10.1007/s11738-001-0020-2pmid: N/A

The influence of three nitrogen salts: NH4NO3, KNO3 and NH4Cl on wheat in vitro cultures was investigated. Both NO 3 − and NH 4 + ions were indispensable for proliferation of embryogenic calli and development of wheat somatic embryos. It is possible to obtain wheat somatic embryos when the medium is enriched with NH4NO3 only as a source of inorganic nitrogen. The results of the statistical analysis showed that the level of NH4NO3 and KNO3 in the medium had a great influence on the efficiency of somatic embryogenesis. We observed tendency that calli on media containing 50 mM NH4NO3 and 0 to 20 mM KNO3 turned out to be more embryogenic than on control MS medium. High concentrations of KNO3- 100 mM inhibited somatic embryogenesis, while 100 mM NH4NO3 did not. The level of total N did not have significant influence on wheat somatic embryogenesis. Ratio NO 3 − :NH 4 + also turned out to be not substantial. We observed that mutual connection of concentration levels between NH4NO3 and KNO3 and between NH4Cl and KNO3 was more important. The efficiency of somatic embriogenesis obtained in the experiment with NH4Cl and KNO3 was significantly lower than in experiment with NH4NO3 and KNO3.

Ayaz, F.; Kadioglu, Asım; Dogru, Ali

doi: 10.1007/s11738-001-0021-1pmid: N/A

Vegetatively propagated Ctenanthe setosa (Rosc.) Eichler (Marantaceae) plants were grown in plastic pots under laboratory irrigation and water deficit conditions. One set of plants was submitted to water irrigation regularly and another set of plants was submitted to water deficit conditions. After a 28 d water deficit stress, the leaves started to roll. Approximately after 33–35 d, the leaves were tightly rolled. Water stress significantly increased the dry weight of rolled leaves. After the 35 d period of water deficit the open (non-stressed) and rolled (stressed, water deficit) leaves were harvested for lipid content and class compositional analysis. The fatty acids consistently identified in phospholipids and glycolipids as well as in total leaf lipid were 16:0, 18:0, 18:1, 18:2 and 18:3. The 16:0, 18:3 and 18:1 acids in control plant and 18:2, 16:0 and 18:3 acids in rolled leaves were determined as the major fatty acids. While the percentage composition of 16:0, 18:1 and 18:3 acids decreased in rolled leaves, the level of 18:2 acid increased. However, the percentage composition of unsaturation in phospholipid (71%) and glycolipid (80.4%) fractions in rolled leaves were found higher than in control leaves. The results show that the degree of unsaturation in phospholipid, glycolipid and total lipid was significantly altered during leaf rolling. The increase in unsaturation degree may regulate membrane permeability and thus adapt the leaves to water stress in the drought environment.

Kato-Noguchi, Hisashi

doi: 10.1007/s11738-001-0022-0pmid: N/A

The n-hexane-, acetone- and water-soluble fractions obtained from an aqueous acetone extract of lemon balm (Melissa officinalis L.) shoots inhibited the germination and the growth of roots and shoots of cockscomb (Amaranthus caudatus L.), cress (Lepidium sativum L.), crabgrass (Digitaria sanguinalis L.), timothy (Phleum pratense L.), lettuce (Lactuca sativa L.) and ryegrass (Lolium multiflorum Lam.). The inhibitory activity of the water-soluble fraction was the greatest, followed by that of acetone- and n-hexane-soluble fractions in all bioassays. The effectiveness of these fractions on the roots was greater than that of the shoots of the test plants. Significant reductions in the germination and growth of the roots and shoots were observed as the extract concentration increased. Such rate-dependent responses of the test plants to the fractions suggest that each fraction might contain allelochemical(s), but that the greatest potential was in the water-soluble fraction.

Kabała, Katarzyna; Kłobus, Grażyna

doi: 10.1007/s11738-001-0023-zpmid: N/A

Large-scale preparation of highly purified tonoplast from cucumber (Cucumis sativus L.) roots was obtained after centrifugation of microsome pellet (10,000 – 80,000 g) on discontinuous sucrose density gradient (20, 28, 32 and 42 %). Lack of PEP carboxylase (cytosol marker) and cytochrome c oxidase (mitochondrial marker) together with a slight activity of VO4-ATPase (plasma membrane marker) and NADH-cytochrome c reductase (ER marker) in tonoplast preparation confirmed its high purity. Using latency of nitrate-inhibited ATPase and H+ pumping as criteria it was established that the majority of tonoplast vesicles were sealed and oriented right(cytoplasmic)-side-out. Strong acidification of the interior of vesicles observed at the presence of both, ATP and PPi, confirmed that obtained tonoplast contains two classes of proton pumps: V-ATPase and H+PPiase.

Kozik, Elzbieta; Dyki, Barbara

doi: 10.1007/s11738-001-0024-ypmid: N/A

A study was made on the self-compatibility in L. hirsutum (LH), L. pennellii (LP) and L. chilense (LC) and on cross-compatibility or preferable unilateral compatibility between these wild species and L. esculentum (LE). From the results of various test crosses and selfings and of cytological research and fruit and seed setting as well it was concluded that the material used is compatible but it differed in the degree of the expression. The highest self- and cross-compatibility was found in LP where number of seed, their viability and also pollen tube growth was similar to LE. Differences between LC and LH in self-compatibility and the congruity with LE were very small on the basis of pollen tube elongation but relatively fewer number of fruit and seed were obtained in the cross LE × LC than from the combination of LE × LH. In the reciprocal crosses when wild species were used as the pistillate parent, no seed were obtained as fertilization was prevented.

Zalewski, Kazimierz; Lahuta, Lesław; Horbowicz, Marcin

doi: 10.1007/s11738-001-0025-xpmid: N/A

Carbohydrate analysis was made of yellow lupin seeds (cv. Juno) and triticale kernels (cv. Dagro), produced by plants exposed to drought stress for 21 days after the initial flowering of the first node of lupin and initial earing of triticale. The seeds of all experimental variants were harvest at full maturity, dried and stored in linen bags at 18–20 °C. Soluble carbohydrates were extracted and analysed as described by Horbowicz and Obendorf (1994).