L. Chinensis (l + chinensi)

Distribution by Scientific Domains

Selected Abstracts

The genetic diversity of perennial Leymus chinensis originating from China

Z. P. Liu
Summary Leymus chinensis is an economically and ecologically important grass that is widely distributed across eastern areas of the Eurasian steppe. A better knowledge of genetic diversity of L. chinensis could be valuable in the efficient utilization, conservation and management of germplasm collections. Genetic diversity in thirty-seven morphological characters of 293 accessions was assessed in three successive years. Based on these qualitative and quantitative characters, the genetic diversity indices (Shannon indices) of traits and geographical populations were estimated, and a principal coordinates analysis and a path analysis were undertaken. Compared with the yellow-green type of L. chinensis, the grey-green type had significantly (P < 005) more genetic diversity. In addition, the path analysis suggested that the combined effects of genetic diversity and vegetative traits could explain 0206 of the total variance in plant reproductive traits. The highest Shannon genetic diversity index of accessions (H = 2252) was observed in accessions from the region of longitude of 124,128E, suggesting the most abundant germplasm of L. chinensis in this region. [source]

Root and rhizome systems of perennial grasses grown in Inner Mongolian grassland, China

Min Ao
Abstract The root and rhizome systems of dominant perennial grasses in Inner Mongolian grassland were clarified. We surveyed the vertical distribution of root and rhizome biomass in the natural stands, and the changes of under-ground biomass and the branching pattern of rhizomes for transplanted plants in a container experiment. Most roots of Leymus chinensis, Bromus inermis, Elymus dahuricus and Agropyron cristatum were distributed in the soil depth of 0,10 cm. Roots of E. dahuricus and A. cristatum were distributed in a shallower soil layer, but those of L. chinensis and B. inermis were distributed in a deeper soil layer. Biomass of above-ground parts increased with growth, resulting in a decreasing ratio of under-ground parts to total biomass. Rhizomes of L. chinensis and B. inermis were distributed in the soil depth of 0,10 cm, but E. dahuricus and A. cristatum did not have rhizomes. L. chinensis had longer rhizomes and new ramets were produced away from their mother plant. B. inermis had many short rhizomes and produced daughter plants near their mother plant. [source]

Variations of Water-Soluble Carbohydrate Contents in Different Age Class Modules of Leymus chinensis Populations in Sandy and Saline-Alkaline Soil on the Songnen Plains of China

Xue-Mei Ding
Abstract Leymus chinensis (Trin.) Tzvel. is a rhizomatous perennial herbage of Gramineae. Reproduction is mainly by vegetative reproduction. Tillering nodes and rhizomes of L. chinensis serve as organs for both vegetative reproduction and nutrient storage. Water-soluble carbohydrate (WSC) contents were measured in tillering nodes, nodes and internodes of rhizomes of different age classes of L. chinensis populations at three development stages, namely the dough ripe stage, the vegetative growth stage after full ripeness, and the withering stage, in two habitats: sandy soil and saline-alkaline soil. The results showed that WSC content in tillering nodes of the three age classes of L. chinensis were all markedly decreased with increasing age in both sandy soil and saline-alkaline soil. A similar trend of changes in WSC contents was observed in the nodes and internodes of rhizomes in different age classes in both habitats. The highest WSC contents were in 2-age-class nodes and internodes of rhizomes, followed by those in the 1 age class, with the lowest WSC contents found in 3-age-class nodes and internodes of rhizomes at the dough ripe and vegetative growth stages after full ripening. In turn, WSC contents decreased with increasing age at the withering stage in both habitats. The WSC content in each age class of internode was higher than that in the node of rhizome at three development stages in both habitats. (Handling editor: Jian-Xin Sun) [source]

Contents of carotenoids, ascorbic acid, minerals and total glucosinolates in leafy brassica pakchoi (Brassica rapa L. chinensis) as affected by season and variety

Peter Hanson
Abstract BACKGROUND: Pakchoi (Brassica rapa L. chinensis) is economically and nutritionally important in East and Southeast Asia. The objective of this study was to evaluate the effects of season and variety on its phytonutrient content (carotenoids, minerals, ascorbic acid and total glucosinolates). RESULTS: Thirty-five varieties were evaluated in one dry season and one wet season field trial at AVRDC,The World Vegetable Center, Taiwan. Mean carotenoid content was about 36% greater in the dry season than in the wet season trial. In contrast, ascorbic acid and total glucosinolate contents were 48 and 72% higher respectively in the wet season than in the dry season trial. Dry matter, calcium and iron contents were also 69, 69 and 21% greater respectively in the wet season than in the dry season trial. Significant differences among entries were found for most phytonutrients; the ranges of variety means were fourfold for total carotenoids, fivefold for iron and total glucosinolates and twofold for calcium. CONCLUSION: Season strongly influences the phytonutrient content of pakchoi grown in the tropics. Significant differences among entries were found for all phytonutrients, and there is potential to increase levels of individual phytonutrients through plant breeding. However, breeding would need to target varieties for either the dry or the wet season. Copyright 2009 Society of Chemical Industry [source]

Vegetation restoration of secondary bare saline-alkali patches in the Songnen plain, China

S.-C. Jiang
Abstract Questions: What factors limit vegetation restoration of secondary bare saline-alkaline patches (BSAP) in the Songnen grassland of northeast China? Is there any adaptive approach to promote revegetation in the shortest time possible and at a low cost? Location: Northeast China. Methods: Considering the climate, soil saline-alkalization and available seed sources, a new approach was adopted to restore vegetation in BSAP, which were formed by the degradation of typical Leymus chinensis grasslands owing to long-term overgrazing. The experimental treatments included no treatment (CK), fencing (F), fencing+inserting cornstalks (FS), fencing+inserting cornstalks+sowing L. chinensis (FSL) and fencing+inserting cornstalks+sowing Puccinellia chinampoensis (FSP). The assumptions behind inserting cornstalks were not only that they would create safe sites for initial revegetation but also that they would enhance seed input by trapping and containing the seeds from seed movement on the BSAP surface. Results: Seed bank shortage was an important factor limiting initial revegetation in BSAP; seed movement on the BSAP surface could provide the necessary seed source if it were contained by effective measures. Vegetation at the sites FS, FSL and FSP was restored well in terms of the above-ground biomass and coverage. Inserted cornstalks acted as safe sites that enhanced the plant survival rate in BSAP; they also enhanced the ability to contain seed movement, thus providing a seed source for initial revegetation. Along with initial revegetation, tussocks around cornstalks can provide better safe sites, which in turn can accelerate subsequent vegetation restoration in BSAP. Conclusions: The approach entails the strategic use of diverse seed sources and the construction of safe sites with agricultural byproducts (cornstalks); therefore, it is a low-cost method and can be used on a widespread scale. The results provide vigorous support in favor of vegetation restoration in BSAP and severely degraded grasslands in the region. In practice, this approach can be used in degraded ecosystems with compacted soil surfaces (including arid and salt-affected soils) to promote revegetation in various regions. [source]