To research difference of photosynthesis characteristic between leaf and pod of rape , the hybrid of Brassica napus Qinyou No.7 with double low and high oil content was chosen to compare the difference of photosyn-thetic gas exchange parameters between leaf and pod under different illumination , CO2 concentration , temperature and time in one day .The results were as below:The change trends of photosynthetic gas exchange parameters of leaf and pod were same along with the change of illumination ,CO2 concentration ,temperature and time in one day .Under the condition of same illumination , the net photosynthetic rate ( Pn ) , stomatal conductance ( Cond ) , tramspiration rate (Trmm),water use efficiency (WUE),limitation stomatal value (Ls) and light quantum efficiency of leaf were all higher than pod in contrast with the intercellular CO 2 concentration ( Ci) ,light saturation point ,light compensa-tion point and light respiration rate of leaf were lower than pod .Under the condition of same CO 2 concentration ,the Pn,WUE,Ls and carboxylation efficiency of leaf were higher than pod ,but the Ci,CO2compensation point and CO2 saturation point and were lower than pod .The optimum temperature of photosynthesis of leaf was lower than pod and the Pn,Cond,Trmm,Ls of leaf were higher than pod in contrast with Ci and WUE of leaf were lower than pod in the range of each optimum temperature and same temperature .The Pn,Cond,Ls and WUE of leaf were higher than pod but the Ci and Trmm were lower than pod in range of whole daily change .%为探究油菜叶片与角果间光合特性的差异，以双低高油甘蓝型油菜杂交种秦优7号为材料，在不同光照、CO2浓度、温度和一日之内不同时间点等条件下比较了叶片和角果间气体交换参数的差别，结果显示：叶片和角果的气体交换参数随光强、CO2浓度、温度、一日之内时间的变化趋势基本相同。在同等光照条件下，叶片的净光合速率、气孔导度、水分利用效率和气孔限制值均高于角果，而胞间CO2浓度蒸腾速率低于角果；叶片的光饱和点、光补偿点、光呼吸速率明显比角果低，而光量子效率显著高于角果。在同等CO2浓度条件下叶片的净光合速率、水分利用效率、气孔限制值均明显高于角果，而胞间CO2浓度低于角果；叶片的CO2饱和点、CO2补偿点均比角果低，而羧化效率则显著高于角果。叶片进行光合反应的最适温度低于角果，在各自最适和相同温度范围内叶片的净光合速率、气孔导度、蒸腾速率、气孔限制值均明显高于角果，而叶片的胞间CO2浓度、水分利用效率则比角果明显降低。在整个日变化范围内叶片的净光合速率、气孔导度、气孔限制值、水分利用效率明显比角果高，而叶片的胞间CO2浓度、蒸腾速率则明显比角果低。
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