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L.virgaurea (Ligularia virgaurea Maxim.) Is widely distributed in the eastern margin of the Tibetan Plateau poisonous weeds, is a typical clone plants. Before people this kind of research focuses on clonal growth, reproduction, distribution characteristics and so on. This paper mainly in the Seed germination, seedling characteristics of the research content, adapt plateau from which to explore this habitat plants life history strategy for the integrated management of grasslands to provide a scientific basis. After two years of field research plots, outdoor and indoor potted plant germination experiment experimental analysis, data processing, the main experimental results are as follows: 1. Mature seeds L.virgaurea hardly sleep at different temperatures germination, seed storage in January as the temperature increases, the seed germination rate, germination rate increased germination delay time decreases. But with increasing storage time at low light conditions more suitable for seed germination, the longer the storage time germination rate is lower. Germination rate was positively correlated with storage time, storage December seed storage is less than the average time required for germination of seeds in January. 2. Seed size on seedling emergence L.virgaurea significantly affected. Large seed germination rate is high, the average emergence time shorter than the small seeds. Light on seed germination rate was not significant, which is consistent with laboratory germination. But light on seed germination time significantly affected the average, large seeds under natural light shortest average emergence time, with the shade gradient increases, the average emergence time extended. 3. Light on L.virgaurea seedling growth significantly. Natural light conditions, the relative growth rate of seedlings from small seeds than large seeds large, but the difference was not statistically significant. In the shade conditions, large seeds and seedlings from small seeds seedling relative growth rate (RGR) are decreased, while seedlings from small seeds fall faster. Seed size and seedling relative growth rate (RGR) no significant correlation, although large seeds plants have a relatively slow growth rate relative (RGR), but it tends to have a faster and larger seedlings maximum growth rate (RGRmax), thereby get greater seedling biomass, competition and the ground appeared early planting its absolute advantage. 4. Light on the age L.virgaurea a seedling and seedling morphology 2nd instar significantly affected. Natural light, L.virgaurea maximum total leaf area, petiole short, root huge smaller angle between the petiole; shady habitats, leaf number becomes smaller, the largest increase in leaf area, leaf thinning, between the petiole angle becomes larger, the leaves were level with the students, mainly from the taproot root system composed of very few lateral roots. Different Ages of light on plant morphology affect the performance of the same. 5. L.virgaurea light on biomass accumulation and distribution was significant. Natural light, seedling aboveground biomass and seed size was positively correlated with greater seedling large seeds. As seedling growth, seedling shoot ratio increased significantly, the plants tend to be relatively more resources allocated to the underground part growth nutrients necessary for the clonal growth reserve; with gradient of increasing shade, large and small seeds plant parts, especially the ground leaf biomass allocation is increased. Increasing trend of small seeds plants more pronounced. Seedling leaf area and seedling biomass was significantly positively related to individual large plants have a larger area of ??photosynthetic structure, resulting in the light of competition and seedling planting in the early advantage. 6. L.virgaurea from the second growing season started early clonal propagation. Clonal morphology on the light showed strong plasticity. With the shade gradient increases, resulting clone rhizome plants significantly reduced severe shady habitats, plants L.virgaurea no clonal stem growth. Whether L.virgaurea exist at the individual level ramet size dependencies. Has been generated in the plants roots, natural light conditions, shorter roots, branching intensity increases; shady habitats, rhizome length increased significantly, reducing the weight per unit length of roots.
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