Abstract: An initial studies were carried out on the ecophysiological characteristics of Medicago varia.cv.Gannong NO.1.Daily variation in leaf photosynthetic rate of M.varia.cv.Gannong NO.1 differed in different months.The results showed that the change was represented as two-peaked curves for May and June,and had midday depression of photosynthesis but single-peaked for July. The daily variation in leaf transpiration rate and stomatal conductance over the whole growth and development can basically be represented by two-peaked curves.Regression and correlation analyses showed that in different months the deciding environmental factors influencing leaf photosynthetic and transpiration rate were different,and even the same environmental factor had an different effect on Pn and Tr.The temperature was the most intensive effect on the photosynthetic rate of M.varia.cv.Gannong NO.1.Between Pn and Tr,Tr was one of the most obvious ecophysiological factor affected by environmental factors.

Key words: Medicago varia.cv.Gannong NO.1, Photosynthesis, Rranspiration, Environmental facors, Correlation

摘要： 研究甘农1号杂花苜蓿(Medicago varia.cv.Gannong No.1)叶片光合生理生态特性。结果表明:不同生育期苜蓿叶片光合生理生态日变化动态各异;光合速率在5月和6月呈双峰型,有光合“午休”现象,在7月呈单峰型;蒸腾速率和气孔导度在各时期均呈双峰型;回归分析和相关分析结果表明,不同时期对叶片的净光合速率和蒸腾速率起主导作用的环境因子有所差异,同一环境因子在不同时间对净光合速率和蒸腾速率的影响程度各异;温度是光合作用影响最主要的环境因子;受环境因子控制最显著的生理特征是叶片的蒸腾速度。

关键词: 甘农1号杂花苜蓿, 光合速率, 蒸腾速率, 环境因子, 相关关系