天目杜鹃生理生态特性的研究

为了对天目杜鹃的成功引种及其在不同生长阶段的养护管理和在园林中的配置提供理论依据,笔者用Li-6400便携式光合作用测定仪对不同大小和不同地点的天目杜鹃生理生态指标进行测定。结果表明:天目杜鹃的净光合速率日变化呈双峰曲线,但幼苗的日平均净光合速率要小于大树的日平均净光合速率,且引种地的日平均净光合速率要小于原产地的日平均净光合速率。天目杜鹃大树和幼苗的蒸腾速率日变化差异较大,天目杜鹃大树蒸腾速率12.00达到最大值,而幼苗要到14.00才达到最大值。通过相关性分析得出空气相对湿度与净光合速率和蒸腾速率都呈负相关;温度、光合有效辐射以及CO2浓度与净光合速率和蒸腾速率都呈正相关。

Study on the Eco-physiology Characteristics of Rhododendron Fortunei

TTo provide the theoretical basis of the successful introduction of Rhododendron fortunei for the disposition in garden and the management in different growth stage, the eco-physiology indexes of Rhododendron fortunei in the different growth stage and the different place was measured by the LI-6400 portable photosynthesis. The result indicated that the curve of diurnal variation of net photosynthetic rate (Pn) was dual-peaked, but the average Pn of the seedlings were smaller than the mature trees and the seedlings in the introduction place were smaller than in the original habitat. The transpiration rate (Tr) of mature trees had reached the peak at 12:00, but the seedlings were at 14:00. The analysis of correlation showed that RH had negative correlation with Pn and Tr. Temperature, PAR and CO2 density had positive correlation with Pn and Tr.