|其他题名||Ecophysiological responses of Incarvillea delavayi Bur. et Franch subjected to water availabilities
|其他摘要||Incarvillea delavayi Bur. et Franch is one of alpine plants with horticultural and medicinal values distributed in the Hengduan Mountains. It is necessary to understand the environmental adaptation for the effective acclimation and cultivation of this species. Up till now, there is little information on the ecophysiological adaptation of Incarvillea species, especially on the photosynthetic response to water availability. However, the observation in the process of cultivation showed that water availability would be one of the determinant factors for the growth and development of Incarvillea species. In present study, the ecophysiological adaptation of I. delavayi subjected to water availabilities is compared between Kunming (alt. 1900m) and Shangri-La (alt. 3200m) to understand the adaptive mechanism of I. delavayi after transplanting to different altitudes and develop effective strategy for its domestication and cultivation. The results are summarized as follows:
1. The response of I. delavayi subjected to water availabilities in Kunming had similar trend with that in Shangri-La. The photosynthetic rate (Pn)、stomatal conductance（gs）、mesophyll conductance（gm）in I. delavayi decreased with the increasing water stress, while the leaf mass area（LMA）、content of chlorophyll and leaf nitrogen per unit area exhibited an adverse trend.
2. Water requirement of I. delavayi changed with the development of the plant. High water availability seemed beneficial for the early fast growing phase. However, during late developmental period mild water stress improved the water use efficiency.
3. The quantitative limitation analysis showed that SL was the dominant limitation on photosynthesis at mild water stress (60-65% of soil field capacity). However, both SL and NSL increased with the increasing water stress. The increment of NSL exceeded SL under serious water stress, and they are similar under severe water stress (25-30% of soil field capacity).
4. The photosynthetic rate (Pn) of I. delavayi in Kunming was lower than that in Shangri-La under the same water availability. Compared with those in Shangri-La, the ratio of chlorophyll a and b, the content of leaf nitrogen per unit area had a slightly increase in Kunming while the leaf nitrogen partitioning coefficient in Rubisco (PR) and bioenergy (PB), nitrogen use efficiency (NUE) were significantly decreased.
5. The environmental differences resulting from different altitudes such as temperature and relative humidity would influence the response of I. delavayi subjected to water availabilities. Photosynthetic characteristics and leaf traits of I. delavayi in Shangri-La changed rapidly with the increasing water stress, and had significantly differences between water treatments. However, there were no significantly differences in photosynthetic characteristics and leaf traits between water treatments in Kunming above 40% of soil field capacity, indicated that the response of I. delavay to water availabilities in Kunming was not as sensitive as that in Shangri-La. We also found that the relative growth rate (RGR) of I. delavay in Kunming was negative below 25% of soil field capacity. The experimental results showed that well water condition was necessary for domestication of I. delavayi especially in drought season, including increasing water availability and air humidity.|
蔡艳飞. 红波罗花对水分的生理生态响应[D]. 昆明植物研究所. 中国科学院昆明植物研究所,2008.