田间大豆光合午休原因的综合研究

STUDY ON THE CAUSE OF MIDDAY DEPRESSION OF PHOTOSYNTHESIS OF FIELD GROWN SOYBEAN

本研究利用主成分分析构造同归模型,利用典型相关分析等方法,对自变量的重要程度进行排序,确定了光合午休的主要原因是气孔因素限制所致.光抑光合也是一个值得注意的因素,但不是主要因素.空气相对湿度、叶片与大气间水汽压差是诱发气孔限制的重要因素.当空气相对湿度较为适中时,叶温的影响较小,在空气相对湿度变坏的情况下,叶温才对光合午休有重要影响.

In this research, the canonical correlation analysis was applied, and the regression model was constructed by principal component analysis for sequencing independent variables. What Caused midday depression of photosynthesis of field grown soybean was mainly stomatal limitation.The light restraint of photosynthesis was also worth noticing, but it was not the main factor. Factors causing stomatal limitation were mainly the air relative humidity and the vapor pressure difference between leaf and air. The effect of leaf temperature was important when and only when the air relative humidity was very low.