旱作条件下旱稻和水稻叶片光合特性及RuBP羧化酶活性的比较

【目的】探讨旱作条件下旱稻、水稻品种叶片光合特性及RuBP羧化酶活性的变化规律，为旱稻品种的选育和高产栽培提供依据。【方法】选择2个旱稻品种（“旱9710”、“秦爱”）和2个水稻品种（“吉农8号”、“长白12号”）为试验材料进行田间旱作试验，于苗期、开花期、灌浆期、成熟期测定其叶片光合特性及RuBP羧化酶活性。【结果】旱作条件下，在整个生育期，旱稻品种叶片的叶绿素含量、RuBP羧化酶活性、净光合速率均显著高于水稻品种（P<0.05），旱稻品种叶片蒸腾速率显著低于水稻品种（P<0.05），水分利用效率极显著高于水稻品种（P<0.01）；旱稻品种叶片的净光合速率与气孔导度、水分利用效率、RuBP羧化酶活性呈显著正相关。【结论】与水稻品种相比，旱稻品种叶片叶绿素含量高，RuBP羧化酶活性强，蒸腾作用弱，水分利用效率高，从而有利于提高旱稻的抗旱性，维持较高的光合效率。

Comparison of photosynthetic characteristics and RuBPcase activity between upland rice and rice in leaves under dry cultivation

【Objective】 The study was performed to explore changes of photosynthetic characteristics and RuBPcase activity in leaves of uplan rice varieties and rice varieties under dry cultivation condition.The purpose was to provide physiological basis for uplan rice varieties breeding and high-yield cultivation.【Method】 With two uplan rice varieties(Han 9710,Qinai)and two rice varieties(Jinong No.8,Changbai No.12)as experimentals materials,photosynthetic characteristics and RuBPcase activity at seedling stage,flowering stage,filling stage and maturation stage were measured under dry cultivation.【Result】 Under dry cultivation,the contents of chlorophyll,net photosynthetic rate(Pn) and RuBPcase activity of leaves in upland rice varieties during different durations were significantly(P<0.05) higher than those in rice varieties.Transpiration rate(Tr) of leaf in upland rice varieties was significantly(P<0.05)lower than that in rice varieties,and utilization efficiency of water(WUE) of upland rice varieties was very significantly(P<0.01) higher than that in rice varieties.The net Pn of uplan rice varieties showed significantly positive correlation with stomatal conductance(Gs),WUE and RuBPcase activity.【Conclusion】 Compared with rice varieties leaves of upland rice varieties have contents of chlorophyll,strong activity of RuBPcase,weak transpiration and increasing WUE,which make for enhancing the drought resistance of upland rice and maintain higer photosynthetic efficiency.