结实期干湿交替灌溉对籽粒蛋白质含量不同的转基因水稻的生理特性及产量的影响

摘要

籽粒蛋白质含量不同的水稻品种产量对水分的响应缺乏研究。以日本晴及以其为亲本获得的两个籽粒蛋白质含量有明显差异的转基因水稻株系为材料，研究了结实期干湿交替灌溉对上述水稻产量和生理特性的影响。结果表明，在结实期相同水分处理条件下，水稻结实率和产量随籽粒蛋白质含量增加而降低。与常规灌溉相比，结实期轻干湿交替灌溉明显提高了水稻结实率和产量。籽粒中 Q 酶活性、根系氧化力、剑叶膜脂过氧化物酶的活性以及茎鞘中非结构性碳水化合物(NSC)的表观输出量也明显提高。籽粒蛋白质含量高的材料的产量和上述生理指标的提高幅度均高于籽粒蛋白质含量低的水稻材料。结实期重干湿交替灌溉则明显降低了水稻的结实率和产量，籽粒中 Q 酶活性、根系氧化力、剑叶膜脂过氧化物酶的活性以及茎鞘中非结构性碳水化合物(NSC)的表观输出量也明显降低，且籽粒蛋白质含量高的材料的产量和上述生理指标的降幅均高于籽粒蛋白质含量低的水稻材料。这些生理指标的变化可能是结实期干湿交替灌溉引起籽粒蛋白质含量不同的水稻材料产量产生差异的重要生理原因。%Little is known on the yield response to water management for those rice cultivars with different protein content in grains (PCG).Effect of alternate wetting and soil drying irrigation during grain filling on grain yield and its physiological traits were investigated with Nipponbare and its two transgenic strains differing in PCG as materials.The results showed that the filled grain rate and grain yield were decreased with increasing PCG under the same water treatment.Alternate wetting and moderate soil drying irrigation (WMD)during grain filling significantly increased grain yield.Q-enzyme activity in rice grains,root oxidation activity,membrane lipid peroxidation enzyme activities in the flag leaves and the translocation of non-structural carbohydrate (NSC)in rice stem were also significantly increased under WMD.And the increasing extent of grain yield and the above physiological traits was higher in the rice lines with higher PCG than those with lower PCG.Alternate wetting and severe soil drying irrigation (WSD)during grain filling significantly decreased filled grain rate and yield,Q-enzyme activity in rice grains,root oxidation activity,membrane lipid peroxidation enzyme activities in the flag leaves and the translocation of non-structural carbohydrate (NSC)in rice stem,when compared with conventional irrigation.And the decreasing extent of grain yield and the above physiological traits was higher in the rice lines with higher PCG than those with lower PCG.The changes of these physiological traits were probably the main reasons for the yield variation of rice lines with different PCG.