氮素对粳稻花后光合响应曲线与氮素利用的影响

摘要

curves changed greatly on the 14th DAF and the photosynthetic CO 2 response curves changed greatly on the 35th DAF.By cluster analysis of grain yields of rice varieties and the parameters of photosynthetic light response curves and photosynthetic CO 2 response curves ,Nanjing 44 and Nanjing 5055 were high efficient cultivars both in LN and HN,their photosynthesis was insensitive both to CO 2 and light intensity under different N applica-tions.It would be an effective way to realize the breeding object both for low N application and high yield by se -lecting high efficient cultivars both in LN and HN .%为明确施氮量对高产粳稻开花后光合能力与氮素利用效率的关系，选取8个不同粳稻材料，分别在开花后14 d和35 d，测定了不同施氮量下（150．0 kg/hm2（LN）、300．0 kg/hm2（MN）、450．0 kg/hm2（HN））剑叶的光强-光合响应曲线、二氧化碳（CO2）-光合响应曲线，并分析其光合参数，最后在收获期考察其产量构成因子。结果表明：根据HN和LN的单株平均产量，将供试材料分为3种类型：类型1：氮素双高效类型，如南粳44，南粳45，南粳5055和南粳46；类型2：高氮高效型，如74142和02102；类型3：双低效类型，如武运粳7号和武育粳3号；供试材料剑叶光合作用对光强和CO2的光合参数分析，施氮量显著改变了其开花后14th的CO2-光合作用响应能力和35th的光强-光合作用响应能力。结合剑叶单株产量以及光合参数的聚类分析表明：施氮量对氮素双高效类型南粳44和南粳5055的光合作用响应能力影响不大，选择氮双高效水稻类型是今后实现减氮高产的有效途径之一。