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Microsatellites are widely distributed in plant genomes and comprise unstable regions that undergo mutational changes at rates much greater than that observed for non-repetitive sequences. They demonstrate intrinsic genetic instability, manifested as frequent length changes due to insertions or deletions of repeat units. Detailed analysis of 1600 clones containing genomic sequences of Vicia bithynica revealed the presence of microsatellite repeats in its genome. Based on the screening of a partial DNA library of plasmids, 13 clones harbouring (GA/TC)n tracts of various lengths of repeated motif were identified for further analysis of their internal sequence organization. Sequence analyses revealed the precise length, number of repeats, interruptions within tracts, as well as sequence composition flanking the repeat motifs. Representative plasmids containing different lengths of (GA/TC)n embedded in their original flanking sequence were used to investigate the genetic stability of the repeats. In the study presented herein, we employed a well characterised and tractable bacterial genetic system. Recultivations of Escherichia coli harbouring plasmids containing (GA/TC)n inserts demonstrated that the genetic instability of (GA/TC)n microsatellites depends highly on their length (number of repeats). These observations are in agreement with similar studies performed on repetitive sequences from humans and other organisms.
Beside RFOs, which are commonly present in legume seeds, seeds of some species contain galactosyl pinitols (GPs). These carbohydrates, like RFOs, have been hypothesized to constitute an important energy and carbon skeletal source during germination. To test this hypothesis we have applied a specific α-galactosidase inhibitor (1-deoxygalactonojirimycin, DGJ) to germinating winter vetch (Vicia villosa Roth.) seeds, containing more galactosyl pinitols than RFOs. The breakdown of RFOs but not that of GPs was completely blocked in both embryonic axes and cotyledons tissues, during the first 18 h of imbibition in DGJ. The inhibitor only decreased the rate of GPs degradation. The inhibitory effect of DGJ on GPs degradation was partially alleviated by addition of sucrose or galactose to DGJ solutions. After three days of germination in water, RFOs and GPs disappeared in axial tissues of seeds imbibed in water, galactose or sucrose. Eighteen-hour imbibition of seeds in DGJ drastically reduced germination, by ca 50%, during the first three days. The inhibitory effect of DGJ decreased during the next seven days of germination. The presence of galactose or sucrose in imbibition solution initially stimulated seed germination, but later this effect was not statistically significant. Our study provides clear evidence that galactosyl pinitols play an important role in early winter vetch seeds germination. Additionally, we suggest that galactosyl pinitols can replace RFOs as reserve material necessary for early germination.
Extrafloral nectaries on the abaxial surface of stipules were investigated in the Vicia angustifolia, Vicia sativa, Vicia sepium and Vicia grandiflora. In V. angustifolia nectaries were also located on the calyx surface. Nectaries were consisted of secretory hairs and 2-3 layers of subepidermal cells. Secretory hair was built af four cells of head, one stalk cell and basal cell. Head cells showed character of transfer cells because of walls ingrowths and dense cytoplasm with numerous mitochondria.
In a field experiment with conservation tillage of Wolska variety of onion the influence of cover plants such as spring rye (Secale cereale) and common vetch (Vicia sativa) as well as varied pre-sowing cultivation measures: no-tillage, disc harrowing during the spring, disc harrowing before the winter in comparison with conventional cultivation, on the content of mineral elements in soil and onion were studied. The content of mineral elements in soil and in onion was modified in greater degree by the changes in weather than by the agro-technical factors. No significant influence of conservation tillage on the content of mineral components in soil or in the onion was found. Soil covered with plant mulch contained slightly more potassium and magnesium in the arable layer in comparison with bare soil. The onion cultivated by using cover plants accumulated slightly more dry mass, N-total and potassium.
Composition and levels of soluble α-galactosides: raffinose family oligosaccharides (RFOs) and galactosyl cyclitols (Gal-C) in developing seeds were measured by high resolution gas chromatography (HRGC) method. The studies were performed on maturing seeds of several wild and cultivated Vicia species: Viciaangustifolia L.(commonvetch), Vicia craccaL. (bird vetch), Vicia grandiflora Scop. (large yellow vetch), Vicia hirsuta (L.) S.F.Gray (tiny vetch), Vicia sativa L. (garden vetch, spring-growing cultivar Kwarta), and Vicia villosa Roth (winter vetch). In all Vicia species similar patterns in the accumulation of RF Os were observed. Galactinol - the donor of galactosyl moieties in α-galactosides biosynthesis was present in the middle stage of seed development, before appearing measurable levels of RFOs. Accumulation of RFOs started parallel with seed desiccation process. At first accumulation of the raffinose, then few days later stachyose and finally verbascose was noticed. In the final stage of seed maturation the verbascose was the main soluble α-galactoside (up to 3 % of dry weight, V. sativa). Besides the RFOs seeds of three Vicia species (V. cracca, V. hirsuta, and V. villosa) accumulated D-pinitol and its α-galactosides (Gal-C). Mono-galactosylpinitols (similar to raffinose) appeared in these species 2-4 days after galactinol, di-galactosyl pinitol A (common name: ciceritol) and di-galactosyl myo-inositol were present several days later than raffinose, and accumulation of tri-galactosyl pinitol A (TGPA) began after accumulation of stachyose. Matured seeds of V. hirsuta contained much more RFOs than Gal-C, opposite to seeds of V. villosa, and V. cracca where concentration of Gal-C was 4-8-fold higher than RFOs. In V. cracca seeds RFOs were almost replaced by Gal-C. In seeds of V. cracca and V. villosa the level of D-pinitol was significantly higher, than the level of myo-inositol. Contents of both cyclitols declined rapidly at the beginning of seed desiccation, when accumulation of RFOs and Gal-C quickly ini creased. We suggest that α-galactosides of D-pinitol can substitute raffinose family oligosaccharides and play similar role during seed maturation and storage.
The role of the abscisic acid (ABA) in biosynthesis of raffinose family oligosaccharides (RFOs) and galactosyl cyclitols (Gal-C) in tiny vetch (Vicia hirsuta [L.] S.F. Gray) seeds was investigated. The ABA was applied through incubation of seed at various stage of its development. The level of RFOs and Gal-C was determined in seed maturing on plant and in seed maturing in vitro. In early stages of V. hirsuta seed development, the ABA activated the biosynthesis of galactinol, although the level of arisen galactinol quickly declined. In the later stages of V. hirsuta seed development ABA had stimulatory effect of RFOs and Gal-C biosynthesis. Influence of ABA on biosynthesis of a-galactosides in Vicia hirsuta seed seems to be dependent on abscisic acid concentration. Low concentration of ABA had stimulatory effect on a-galactosides biosynthesis, but high concentration of ABA inhibited the process.
W łupinach i liścieniach nasion różnych gatunków i odmian wyki występują inhibitory pepsyny, trypsyny i chymotrypsyny.
Scorzonera hispanica is a rich source of inulin – a glycoside which has a positive effect on human and animal organisms. The paper presents studies on fungi threatening the cultivation of scorzonera. Soil mulching with intercrop cover crops such as oats, tansy phacelia and spring vetch had a positive effect on the population and healthiness of the seedlings and the roots of the studied plant. The following fungi were most frequently isolated from the infected underground organs of scorzonera: Alternaria alternata, A. scorzonerae, Botrytis cinerea, Cylindrocarpon didymum, Fusarium culmorum, F. oxysporum, F. solani, Rhizoctonia solani, Phytophthora sp. and Sclerotinia sclerotiorum. Among the applied mulching plants, oats proved to be the most effective in inhibiting the occurrence of the enumerated fungi species.
Changes in the accumulation of two types of α-D-galactosides: raffinose family oligosaccharides and galactosyl pinitols were compared with changes in the activities of galactosyltransferases during winter vetch (Vicia villosa Roth.) seed development and maturation. Occurrence of galactinol and raffinose in young seeds and changes in activities of galactinol synthase and raffinose synthase during seed development indicated that formation of raffinose oligosaccharides (RFOs) preceded synthesis of galactopinitols. Although transfer of galactose residues into raffinose oligosaccharides increased as seeds were maturing, at late stages of seed maturation the accumulation of galactopinitols was preferred to that of RFOs. In the present study, activities of enzymes transferring galactose moieties from galactinol to D-pinitol forming galactopinitol A, and further transfer of galactose moieties from galactinol to mono- and di-galactopinitol A were detected throughout seed development and maturation. This is a new observation, indicating biological potential of winter vetch seeds to synthesize mono-, di- and tri-galactosides of D-pinitol in a pathway similar to RFOs. The pattern of changes in activities of stachyose synthase and enzymes synthesizing galactopinitols (named galactopinitol A synthase and ciceritol synthase) suggests that formation of stachyose, mono- and di-galactopinitol A (ciceritol) is catalyzed by one enzyme. High correlation between activities of verbascose synthase and enzyme catalyzing synthesis of tri-galactopinitol A from galactinol and ciceritol (named tri-galactopinitol A synthase) also suggests that biosynthesis of both types of tri-galactosides was catalyzed by one enzyme, but distinct from stachyose synthase. Changes in concentrations of galactosyl acceptors (sucrose and D-pinitol) can be a factor which regulates splitting of galactose moieties between both types of galactosides in winter vetch seeds.
Nectaries of investigated species of Vicia were ranked into 3 morphological types : automorphic (V. sepium L.) transitoric (V. angustifolia L., V. satira L. , V. Villosa Roth, V cracca L.) and flat epimorphic (V. hirsuta (L.) S. F Gray and V. tetrasperma (L.) Schreb.). The best nectaring was connected with well defined nectary structure, and moreover quantity of neclar was correlated with nectary size but was not depended on number оf secretory stomata. Sucrose dominated in the nectar of 6 species of vetches, the exception was balanced nectar of V. tetrasperma.
The object of the studies were saprophytic bacteria and fungi isolated from the soil after the cultivation of spring rye and common vetch. The studies were conducted in laboratory conditions. The antagonistic effect of the isolates of Bacillus spp., Pseudomonas spp., Trichoderma hamatum and Trichoderma koningii was determined towards such pathogenic fungi as Alternaria alternata., Botrytis cinerea, Fusarium culmorum, Fusarium oxysporum, Fusarium solani, Phoma exigua var exigua, Pythium irregulare, Rhizoctonia solani and Sclerotinia sclerotiorum. It turned out on the basis of the obtained results that the highest antagonistic effect was characteristic of the isolates of Trichoderma koningii, while the smallest of Trichoderma hamatum. Among the examined bacteria isolates Pseudomonas spp. appeared to be a poorer antagonist than Bacillus spp.
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