全生育期干湿交替灌溉对稻米品质及淀粉特性的影响

Effects of alternate wetting and drying irrigation during whole growing season on quality and starch properties of rice

以常规籼稻和杂交籼稻品种为材料,在大田种植条件下,全生育期设置常规灌溉(CF)和干湿交替灌溉(WMD)处理,观察不同灌溉方式对稻米品质和淀粉特性的影响。结果表明:与常规籼稻品种相比,杂交籼稻品种具有较高的产量、灌溉水利用效率、精米率、整精米率、总蛋白质及其组分含量、消减值、相对结晶度、1045/1022cm-1红外比值、中淀粉粒体积百分比以及灌浆早期和中期的籽粒关键酶活性、剑叶光合速率和根系氧化力。与CF相比,WMD可改善稻米的加工和外观品质,增加支链淀粉和总淀粉含量、中淀粉粒数量和体积百分比,优化蛋白质组分,提高淀粉的峰值黏度、热浆黏度、最终黏度、崩解值以及灌浆期籽粒关键酶活性、剑叶光合速率和根系氧化力,降低淀粉消减值、相对结晶度、大淀粉粒数量和体积百分比。在WMD下,杂交籼稻品质和淀粉特性改善幅度大于常规籼稻。这说明全生育期干湿交替灌溉可获得较高的产量和水分利用效率,并能明显改善杂交籼稻米质及淀粉特性。

Two types of inbred indicarice and hybrid indicarice varieties were grown in field experiments with two irrigation regimes,CF(continuous flooding)and WMD(alternate wetting and moderate soil drying)were conducted during the whole growing season of rice.Present investigation was aimed to determine the effect of the different irrigation regimes on quality and starch properties of rice.Results showed that compared with inbred indicarice varieties,hybrid indicarice varieties performed higher yield,irrigation water use efficiency,milled rice,head milled rice,total protein and components contents,setback value,relative crystallinity,1045/1022IR ratio,percentage of middle-sized granules volume,and key enzymes activities in grains,flag leaf photosynthetic rate and root oxidation activity during grain filling stage.Compared to CF,WMD improved the milling and appearance quality,increased the amylopectin and total starch contents,percentage of middle-sized granules number and volume,optimized the protein components,enhanced the starch viscosity of peak,hot and final,breakdown value,and key enzymes activities in grains,flag leaf photosynthetic rate and root oxidation activity during grain filling stage,decreased the starch setback value,relative crystallinity,percentage of large-sized granules number and volume.The improvement of quality and starch properties of hybrid indica rice ter than that of inbred indica rice varieties under W MD.The results suggested that alternate wetting and moderate soil drying irrigation regime could achieve higher yield and water use efficiency,and sig-nificantly improve quality and starch properties of hybrid indica rice varieties.