盐逆境对水稻产量、光合特性及品质的影响

【目的】江苏沿海滩涂种植水稻是促进盐土脱盐改良和开发利用滩涂的主要技术之一,研究盐逆境对水稻产量、光合特性和稻米品质的影响,可为发展滩涂种稻提供参考和理论依据。【方法】以耐盐性较好的通粳981、盐稻12、盐稻10号和南粳5055等4个粳稻品种为材料,设置非盐逆境(S0,电导率0.207 d S/m)和逆境(S1,电导率1.112 d S/m)2个处理,分别测定产量及其构成因素、光合参数、稻米品质和淀粉黏滞特性。【结果】与非盐逆境相比,盐逆境下水稻产量显著下降,仅为非逆境的40.5%,单位面积穗数差异不显著,每穗粒数和千粒重显著减少;光合速率、胞间CO2浓度显著下降,而气孔导度和蒸腾速率差异不显著;稻米加工品质显著下降,外观品质变化不大,直链淀粉含量显著下降,蛋白质含量显著增加;峰值黏度、热浆黏度、最终黏度、崩解值和回复值均未发生显著的变化,消减值和起始糊化温度显著增高。【结论】盐逆境对水稻产量、光合参数、稻米品质等均有不利的影响,可在盐逆境对产量、品质影响的关键时期孕穗期和灌浆结实期采取措施缓解盐逆境的危害。

Performance of Yield,Photosynthesis and Grain Quality of japonica Rice Cultivars Under Salinity Stress in Micro-plots

【Objective】Rice growing is one of the widely utilized technologies for desalting, improving and exploiting tidal flat in Jiangsu coastal beach. The objective is to reveal the effects of salinity stress on rice yield, photosynthetic parameters, grain quality and starch viscosity, providing a reference and laying a theoretical basis for developing rice production in Jiangsu coastal beach.【Method】Four japonica rice varieties with better salt tolerance, Tongjing 981, Yandao 12, Yandao 10 and Nanjing 5055 were used to investigate the yield and its components, photosynthetic parameters, rice quality and starch viscosity under salinity stress (S1, 1.112 dS/m for EC1:5) and no salinity stress (S0, 0.207 dS/m, control).【Result】Compared with the control, rice yield decreased significantly under salinity stress, was only 40.5% of that of the control, panicle number per unit area had no significant difference, while grain number per panicle and 1000-grain weight also decreased significantly. The photosynthetic rate and intercellular CO2 concentration decreased significantly, but stomatal induction and transpiration rate had no significant difference between S0 and S1. The processing quality of rice, together with amylose content decreased significantly, the appearance quality almost remained unchanged, while protein content increased significantly. The peak viscosity, trough viscosity, final viscosity, breakdown value, consistence value showed no significant changes, the setback value and pasting temperature increased significantly.【Conclusion】Salinity stress had adverse effects on yield, photosynthetic parameters and grain quality of rice. During the critical period of salt stress on yield and quality, such as booting stage and filling stage, measures should be taken to alleviate salt stress.