The Plasticity Research To Seedlings Of Taxus Wallichiana In Different Altitude And Climate Types

Taxus wallichiana is an important taxon of Taxus plant, which is one of the major sources of taxol and other taxanes materials as well. But now the species is faced with the danger of extinction, as the poor competitive capacity of the population, slow natural regeneration, limited distribution, human disturbance, etc. Recently, a lot of researches on Taxus wallichiana have been done for the species protection and the sustainable development of taxol industry, such as cultivation with exotic species, cuttage seedling-raising, selection of superior trees, construction of cutting orchard, seed germination, phytochemistry, resource protection, metabolic products, etc.However, there were few reports on plasticity adaptation of Taxus wallichiana in the seedling stage, especially effects of the morphology, biomass and taxanes content with different altitude and climatic factors. Thus, the research would be conducive to the development and protection of the tree species. On the other hand, there might be a valuable probe or complement to studies of biological and ecological characteristics of Taxus wallichiana.Five zones of different altitude and climate types were selected for the field experiment. The growth yield, biomass and taxanes content of the same provenance, age and substrate of Taxus wallichiana were studied, which were cultured in the open in Lijiang, Kunming, Qiubei, Pu'er and Puwen respectively. The difference, correlation, and regression between factors of geography, climate and above data were analyzed, results as follows:1. It showed the limited morphological plasticity in juvenile stage of Taxus wallichiana in the heterogeneous environment. The air temperature and the precipitation were two key environmental factors to morphogenesis of the seedlings.2. There was no significant deviation in total dry weight of seedlings of Taxus wallichiana in different sites, and also no significant correlation with environmental factors. There was no significant effect on total fresh weight of the seedlings with geography factors. Annual mean temperature, aridity, sunshine hours, and frost period were key meteorological elements to the impact on total fresh weight. 3. According to the final biomass of seedlings of Taxus wallichiana in different zones, it showed Southern Yunnan>Northwestern Yunnan>Southeastern Yunnan>Central Yunnan.4. According to the R/C of seedlings of Taxus wallichiana in different climate types, it showed Pu'er>Puwen>Lijiang>Qiubei>Kunming.5. There was the significant positive correlation between baccatin-III content of seedlings of Taxus wallichiana and the annual precipitation. There was the significant negative correlation between the altitude and 7-XYl-TAXOL content, which showed significant positive correlations with annual mean temperature,≥10℃accumulated temperature, and annual precipitation. There was the significant negative correlation between the altitude and cephalomannine content, which showed the significant negative correlation with the frost period as well, but showed significant positive correlations with annual mean temperature,≥10℃accumulated temperature, and annual precipitation. There was the negative correlation between the altitude and taxol content, which showed the significant positive correlations with annual mean temperature and≥10℃accumulated temperature, and showed the most significant positive correlation with annual precipitation.6. Altitudes, annual mean temperature,≥10℃accumulated temperature, and annual mean precipitation were key environmental factors to act on the content of 7-XYl-TAXOL, cephalomannine, and taxol in seedlings of Taxus wallichiana. The annual mean temperature was the most important factor in the action.7. According to the annual change of the total taxanes content of seedlings of Taxus wallichiana, it showed the maximum content of seedlings to Lijiang and Pu'er in the third quarter; it showed the maximum content of seedlings to Kunming and Qiubei in the second quarter; it showed the high increment of the total content of seedlings to Puwen in the third quarter, but lower than the initial phase.