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Yunnan yew (Taxus yunnanensis Cheng et LK Fu) system at the national level to protect plants and conifers class international expert group (CSG) identified three endangered species, mainly distributed in China's western and northwestern Yunnan, southwestern Yunnan, Yunnan in western Sichuan, southeastern Tibet and other places. Taxus due to widely distributed, abundant resources, paclitaxel (Taxol) Taxol content and become the main raw material forest tree species in Yunnan, Sichuan, Chongqing, Tibet and other provinces (cities, districts) large-scale development. Taxol is the most anti-cancer activity of natural compounds, has been more than 40 countries for the treatment of a variety of cancers, medicinal value and high economic value. On the one hand, paclitaxel is currently the world's most recognized broad-spectrum, high efficiency and side effects of anti-cancer drugs; hand, yew wood precious and beautiful tree, highly ornamental. So strengthen the physiological and ecological studies of Taxus not only for the conservation of Taxus provide important theoretical reference, and for the cultivation of Taxus forests and large-scale production of raw materials to provide technical guidance, and therefore have a significant socio-economic value . In this study, pot experiment, in different conditions, environmental factors, mainly nutrients and light treatment on the growth of Taxus, photosynthetic physiology as well as the synthesis and accumulation of paclitaxel were one-year study period. The main results are as follows: 1. Nitrogen (N), phosphorus (P), potassium (K) of three elements on the growth of seedlings of Taxus impact: N elements of their role in promoting maximum; while low concentrations and over High concentrations of N supply is not conducive to the growth of seedlings, the concentration of N is supplied only moderately so that the growth will be the maximum amount. High concentrations of low concentrations of P and K is not conducive to their growth increased. In the light quality and intensity on seedlings of Taxus aspects: a qualitative change in the light of some of the seedlings will promote the growth of index changes, Blu-ray treatment can promote the growth of its height, but detrimental to their ground diameter growth; red treatment can promote the growth of its ground diameter, yellow handle can promote the growth of its crown and branches. Moderate shade can promote seedling growth, but low and severe shade will inhibit their growth. 2 in the N, P, K seedlings of Taxus three elements on Photosynthetic Physiological effects: moderate supply of N elements can enhance seedling photosynthetic activity, high concentrations of N supply can reduce seedling photoinhibition; high concentration of P element supply can enhance their photosynthetic activity, but also can make the light saturation point (LSP) increased. In the light quality and intensity on photosynthesis of Yunnan yew seedling physiological effects: a qualitative change in light and shade will reduce the photosynthetic activity of seedlings, seedlings of Taxus shade reduces the photosynthetic activity. But from the maximum net photosynthetic rate (P max) point of view, can be improved moderately shade seedlings of Taxus maximum net photosynthetic rate; while severe shade can increase the apparent quantum efficiency (AQY), thereby enhancing its low light capacity utilization. But in general, is not conducive to heavy shade photosynthetic activity of Taxus enhancements. Blu-ray will significantly reduce the photosynthetic activity of seedlings, seedlings of Taxus red light can improve the Pmax and AQY, yellow can improve its LSP. 3 in the N, P, K three elements seedlings of Taxus paclitaxel on the synthesis and accumulation of: N elements can significantly promote its taxol content increased, P and K elements taxol content of its role in promoting certain, but effect is not too large. Taxus nutrients for the supply of both N elements, or elements of P and K to be their basic needs-based, if the supply of its concentration exceeds a certain amount, will be its synthesis and accumulation of paclitaxel produce a certain rejection. In light on seedlings of Taxus paclitaxel content areas: light quality treatment on stems and leaves showed no significant effect of paclitaxel, yellow can significantly increase its roots taxol. Meanwhile, in general, can make the shade seedlings of Taxus paclitaxel was reduced, but does not make it yield.
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