水分胁迫和不同形态氮素营养对苗期水稻光合特性的影响

Effect of nitrogen form and water stress on basic photosynthetic characteristics of rice at seedling stage

采用营养液培养及聚乙二醇(PEG 6000)模拟水分胁迫的方法,研究不同形态氮素营养和水分胁迫耦合作用下水稻新完全展开叶的光合特性。结果表明:水分胁迫对供NH4+-N营养水稻的生物量、叶面积、净光合速率、气孔导度、细胞间隙CO2浓度、羧化效率均无显著影响,但显著抑制了供NO3--N营养水稻的上述指标。NH4+-N营养提高了水分胁迫下水稻叶片叶绿素a、叶绿素b的含量。水分胁迫并没有影响不同形态氮素营养下水稻的表观量子效率。

In order to study the photosynthetic characteristics of rice plants under different nitrogen form nutrition and water stress, a hydroponic experiment with simulated water stress by PEG 6000 was conducted. Parameters related to photosynthesis were studied including biomass, leaf area, chlorophyll, net photosynthetic rate （ Pn）, stomatal conductance （ Gs）, intercellular CO2 concentration （ Ci）, carboxylation efficiency （ CE）, and apparent quantum yield （AQY）. The results showed that under ammonium nutrition there were no significant differences on biomass, leaf area, net photosynthetic rate, carboxylafion efficiency of rice plant between water stress and non-water stress. However, under nitrate nutrition, the above mentioned parameters decreased under water stress condition. The contents of chlorophyll a and chlorophyll b were higher in the rice plants supplied by ammonium under water stress than that of non-water stress. There were no significant difference in apparent quantum yield of rice plant supplied with three nitrogen form between water stress and non-water stress.