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The investigations on mechanical properties of reed stems face numerous difficulties, because of their anisotropy, heterogeneity, shell-like structure, small lateral dimensions of stems and huge diversity of species and habitats of origination. Aware of all difficulties to cope with, the basic experiment has been conducted, that is the uni-axial tension test for reed stems, with- and without joints. The strain-stress relation, at tension, displayed an exponential character, showing material stiffening with the growth of strain. Test results incline to conclusion, that stem-pieces without joints are equally stiff as pieces with joints, however, they are twice as strong as the latter. It means, that joints can be perceived as fragile (in the sense: “brittle”) discontinuity in structure of reed stems. The results of the test have been put through critical estimate and analysis tending to statistical modelling of the load-carrying ability of reed stems.
Expressed Sequence Tags (ESTs) are short, usually unedited sequences obtained by single-pass sequencing of cDNA clones from any cDNA library. Analyzing and comparing ESTs can provide information on gene expression, function and evolution. Large-scale EST sequencing has become an attractive alternative to plant genome sequencing. Currently, plant EST coltections comprise over 3.8 miliion sequences from about 200 species. They have proved to be a valuable tool for gene discovery and plant metabolism analysis. Several plant-specific EST databases have been created which provide access to sequence data and bioinformatics-based tools for data mining. Searching EST coltections allows pre-selection of genes for preparing cDNA arrays, targeted to bring maximum information on specialized processes, like stress response, symbiotic nitrogen fixation etc. Also, EST-based molecular markers such as SNP, SSR, and indels are fast developing tools for breeders and re searchers.
Kalanchoë daigremontiana leaves contain phenolic compounds, which are one of the determinants of plant therapeutic properties. Light and scanning electron microscopes were used to analyse the structure of leaves. The main aims of the study included the analysis of the anatomy of leaves, localisation of phenolic compounds, and identification of phenolic acids. The thickness of the amphistomatic leaf blades, the number, the size of stomata, and the value of stomatal index, as well as the structure of the parenchyma cells have indicated that K. daigremontiana is adapted to arid environments. The histochemical assays revealed the presence of phenolic idioblasts in the leaf blades and petioles. The idioblasts were located in the epidermis, subepidermal layer, a deeper portion of the mesophyll, and in the sheaths of vascular bundles. The phytochemical analyses of leaves demonstrated the presence of gallic, ferulic, caffeic, p-coumaric, and protocatechuic acids in the form of esters. We carried out the research of the anatomical structure of K. daigremontiana leaves, which has been insufficiently documented to date. We have also revealed new localisation of phenolic compounds in the leaf tissues of this species.
In order to evaluate the relationship between traits affecting the seed yield of the garden cress, phenotypic correlations between seed yield and yield components were detected, direct and indirect effects of yield components on yield and its role in the description of diversity were estimated, and the experiment was conducted in a randomized complete block design with three replications in 2017. The ANOVA showed that the difference among accessions was significant for all traits. There was a significant phenotypic correlation between yield and most of the traits. The highest value of phenotypic correlation was obtained between seed yield and the ‘thousand seed weight’ (0.97). The regression analysis showed that the seed yield was highly influenced by the ‘thousand seed weight’, leaf height and the number of seeds per silique of the lateral branches and the main axis. These three traits constituted about 89% of changes in the total yield, while the ‘thousand seed weight’ was the most effective trait that entered the model and explained 51% of the variation. The path analysis of phenotypic correlation showed that the ‘thousand seed weight’ had the greatest direct effect on the yield (7.21). The ‘thousand seed weight’ had a positive indirect impact on other traits as well. As a result of the factor analysis, 3 independent factors explained about 79.33% of the yield variation. These factors consisted of the number of seeds per silique of the lateral branches, the number of seeds per silique of the main axis and the ‘thousand seed weight’.
Different nutrient media (MS [Murashige and Skoog 1962]; QL [Quoirin and Lepoivre 1977] and WPM [Lloyd and McCown 1980]); plant growth regulators BA (benzil adenin), GA3 (gibberellic acid), IBA (indole-3-butyric-acid), NAA (naftalen acedic acid); and sucrose concentrations were studied to determine the in vitro culture effects on healthier and faster seedling development from mature lentisk (Pistacia lentiscus L.) seeds. After 28 days of culture, the percentage of germinated seeds was the highest (70%) in the full-strength MS medium. The cytokinin BA was superior to other tested treatments in terms of its ability to promote germination of lentisk seeds. When tested at different concentrations, sucrose gave the best results obtained at concentrations of 1–4%, whereas high concentrations (6 and 8%) mainly decreased germination rate and there was no a regular pattern for elongation of the aerial parts of plants. With this described protocol, on average 76.67% seeds germinated 4 weeks after culture. Developed seedlings were satisfactorily acclimatized in sterilized peat, soil and perlite containing compost, with high percentage survival viability was obtained 9 months after transfer to in vivo conditions (93.33%). The results obtained showed that the enriched full-strength MS medium supplemented with 1 mg L–1 BA and 3% sucrose induced homogeneous and healthy seedling development in a period of 4 to 8 weeks of culture.
Garden perennials are a source of floristry material produced in field or under covers. A perennial producing long, leafy shoots, which in flower arrangements might successfully substitute fern or palm leaves, is Polygonatum multiflorum. The variety characterizing with decorative white margined leaves is ‘Variegatum’. To improve their quality, the growth stimulator Actisil Hydro Plus, which contains 0.6% of active silicon in a form of orthosilicic acid was applied. The aim of the conducted experiment was to estimate the influence of silicon and a place of cultivation (tunnel and open field) on post-harvest quality determined with morphological features, vase life longevity and mechanical properties of Polygonatum multiflorum (L.) All. ‘Variegatum’ stems. The plants were sprayed with water solutions of Actisil in concentrations: 0.2%, 0.3%, and 0.4%, six times during the growing season in weekly intervals, starting from the first decade of May, always in the morning. It was stated that cultivation of Polygonatum in the unheated foil tunnel increases quality of shoots for cut greenery, determined with morphological features and post-harvest longevity. Cultivation of Polygonatum in a foil tunnel and spraying plants with Actisil in concentrations of 0.3 or 0.4% is advantageous due to possibility to increase a number of shoots from 20% to over 31%, their length from 9% to 11% and fresh weight from 52% to 71%, in comparison to control plants. It is advised to treat plants cultivated in a tunnel, with Actisil in concentration of 0.4% as it improved shoots quality evaluated with their diameter and lower leaves blade area. Spraying plants with Actisil in concentrations of 0.2–0.4% in the tunnel and 0.2% in field prolongs post-harvest shoots longevity by 3–4 days. Plants cultivated in the tunnel characterize with higher strength of shoots determined with higher maximum force causing permanent damage and lower stem deflection than plants cultivated in field. Plants grown in a tunnel and sprayed with Actisil in concentrations of 0.4% characterized with the strongest shoots after 14 days of storage, however a similar effect was observed with the concentration of 0.3% and in case of plants cultivated in field and sprayed with 0.4% of Actisil.
Globally, the application of rootstocks for grapevine cultivation has been a standard, while in the northern regions, like in Poland where the viticulture tradition is relatively short, the selection of the most suitable rootstock types requires multi-year observation and research. The objective of the present study was to assess the effect of six following rootstock types: ‘101-14 Mgt’, ‘161-49C’, ‘125AA’, ‘5BB’, ‘SO4’, ‘SORI’, and own-rooted vines on yield quantity and quality of ‘Regent’ grapevine in south-eastern Poland. The three-year research period indicates that the vines on ‘125AA’ tended to produce not only the highest yields but had positive influence on the number and weight of clusters and berry weight as well. Whereas the vines grafted onto ‘161-49C’ gave the lowest yields and had the smallest number of clusters per vine. The fruit extract content in ‘Regent’ grapes on ‘101-14 Mgt’ rootstock was found to be significantly lowest among those under study. The extract content and yield of grapevines evaluated in the own-rooted vines and those grafted to the rootstocks which formed one group, did not differ.
Indian jujube (Zizyphus mauritiana Lamk.) is mostly cultivated in tropical and sub-tropical regions of the world. Many native and exotic jujube cultivars are grown for fruit production in Pakistan. However, little research work has been conducted on various aspects of jujube i.e. morphological and biochemical characterization of available germplasm. Therefore, fruits of thirteen genotypes were collected to study the biodiversity through physico-chemical analysis during the years 2015 and 2016. The aim of the present study was to investigate the relationship among various physico-chemical attributes of the jujube through Pearson’s correlation that may have greater importance for breeders during the selection of desirable genotype. The cultivar Foladi had the maximum fruit weight (30.49 g), pulp weight (28.42 g) and fruit diameter (36.75 mm) among all the cultivars. The maximum fruit length was recorded in Umran-13 (45.16 mm), while the maximum seed weight (2.70 g) was found in Dilbahar. Khobani had the maximum TSS (14.92 ºBrix). The highest level of acidity (0.74%) was recorded in Gorh. Akasha had highest vitamin C content (72.53 mg 100 mL–1 juice). The cultivars Sadqia, Umran-13, Mehmood wali, Yazman local and Gorh were much sweeter due to the maximum total sugars content (9.74–10.09%). The maximum antioxidant capacity was measured in Mahmood wali (616.13 mM Trolox 100 mL–1), Pak white (615.02 mM Trolox 100 mL–1) and Seedless (600.46 mM Trolox 100 mL–1), while antioxidant activity was significantly higher in Sadqia (40.604%). The maximum amount of total phenolic content was determined in Umran-13 and Sadqia (243.06 and 239.25 µg GAE mL–1 juice, respectively). The highly significant correlation (0.99) was observed between the fruit weight and pulp weight. Antioxidant activity and total phenolic content were also strongly correlated (0.70). Principal component analysis was made to determine the relationship among the genotypes and their variables. Dendrogram constructed on the basis of morphological attributes, divided 13 genotypes into four main clusters. Among the cultivars, Khobani and Mehmood wali share the maximum similarity (78%). Biochemical characteristics also divided the genotypes into three main clusters. The cultivars Pak white and Seedless had the maximum similarity (75%) among all the cultivars.
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