对生玉米叶面积分布、 蒸腾速率和水分利用率的研究

研究了6个品种(系)的对生和互生玉米的叶面积分布、 蒸腾速率(Tr)和水分利用率(WUE)。 结果表明， 对生玉米单株叶数和叶面积比互生玉米分别高出192%～220%和130%～190%。 两者的不同叶位与叶面积之间均呈极显著的二次抛物线回归关系， 即判断得最大叶面积的叶位数为6。 后期(灌浆期起)， 对生玉米叶绿素含量高于互生的， 差

Studies on Distribution of Leaf Area, Transpiration Rate and Water Use Efficiency in Oppositifolious Maize

The results indicated that the leaf number and leaf area in plant of oppositifolious maize had increased by 192%～220% and 130～190%, respectively, as compared to that in plant of alternative, but the mean leaf area of oppositifolious maize was lower than that alternative. As it is seem from results that there was a significant parabolical regression relationship between different leaf position and leaf area in oppositifolious and alternative maize, i.e., according to the model of nonlinear regression, 6 of the leaf position in largest leaf area are estimated. After filling stage, cholorophyll content in oppositifolious maize was higher than in alternative. On clear days the diurnal fluctuation of transpiration rate (Tr) and stomatal conductance (Gs) of oppositifolious and alternative maizes leaves shows a single peak, being highest before and after noon, and related significantly to photon flux density (PFD), leaf temperature (T1) and vapor pressure deficiency (VPD). PFD has a significant effect on Tr and Gs. The results also indicated that there was no significant difference between oppositifolious and alternative maizes to Pn. But Tr and Gs in oppositifolious maize was lower than alternative, and water use efficiency (WUE) was higher than that alternative, (α=0. 05), indicating that the oppositifolious maize adapted to drought condition better than alternative did.