【摘要】 【目的】全球气候变化不断加剧导致江西双季稻区晚稻季结实期弱光胁迫现象频现，造成水稻产量和品质明显下降。探明不同类型优质晚稻品种产量和品质对结实期弱光胁迫的响应规律，为耐弱光胁迫品种培育以及高产高效栽培提供科学依据。【方法】以籼粳杂交稻甬优1538、杂交粳稻申优26、杂交籼稻泰优871为供试材料，在大田试验条件下设置结实期不遮光和遮光70%2个处理，研究遮光处理对水稻产量及其构成、干物质积累与转运及稻米品质的影响。【结果】与不遮光处理相比，结实期遮光处理下不同类型晚稻品种的花前干物质转运率及贡献率分别显著提高34.66%～288.12%和159.08%～638.93%，但花后干物质质量、花后干物质占比及其贡献率分别显著下降45.41%～81.40%、30.39%～73.79%、17.40%～64.35%，成熟期干物质质量和收获指数分别显著下降21.57%～29.54%、15.70%～26.54%，从而导致结实率和千粒质量分别显著下降31.12%～47.70%和1.67%～3.87%，产量显著下降39.19%～51.21%；同时，结实期遮光导致不同类型晚稻品种的整精米率、峰值黏度、崩解值、直链淀粉含量显著降低，垩白粒率和垩白度（泰优871例外）、消减值和蛋白质含量显著增加，以及米饭质构特性变差（甬优1538例外）。相较于泰优871和申优26，甬优1538在遮光条件下花后干物质质量、花后干物质占比及其贡献率分别显著提高43.39%～301.44%、33.30%～237.42%和7.19%～179.87%，成熟期干物质质量、收获指数、结实率也随之显著提高，最终产量显著增加25.73%～29.23%。【结论】结实期遮光条件下甬优1538较高的花后干物质积累及贡献率为籽粒灌浆结实提供了较多的碳水化合物，从而减轻遮光对其产量和品质形成的影响。江西双季晚稻季种植籼粳杂交稻甬优1538既可以获得高产、稳产，又能维持较优的食味品质。更多还原

【Abstract】 [Objective]With the aggravation of global climate change,low-light stress during grain filling stage has happened frequently in late season of double rice cropping system in Jiangxi province,which has resulted in significant decline in grain yield and quality.This study aims to verify the response of grain yield and quality formation of different types of high-quality rice varieties to low-light stress during grain filling stage,thus providing scientific basis for breeding varieties with low-light stress tolerance and establishing cultivation practices of high yield and high efficiency.[Method]Field experiments were conducted with three types of high-quality late rice,i.e.,indica-japonica hybrid rice Yongyou 1538,japonica hybrid rice Shenyou 26 and indica hybrid rice Taiyou 871,and then grain yield and its components,dry matter accumulation and translocation,and rice quality were investigated under two light conditions(no shading and shading 70% natural light) during grain filling stage.[Result]Compared with the non-shading treatment,the transportation rate and contribution rate of dry matter before anthesis for the three rice varieties under shading conditions were significantly increased by 34.66%-288.12% and 159.08%-638.93%,respectively.However,the proportion of dry matter after anthesis to total dry matter at maturity and its contribution rate decreased significantly by 45.41%-81.40%,30.39%-73.79% and 17.40%-64.35%,respectively.Meanwhile,the dry matter at maturity and harvest index decreased significantly by 21.57%-29.54% and 15.70%-26.54%,respectively,which subsequently led to a significant decrease in grain setting rate by 31.12%-47.70%,1000-grain weight by 1.67%-3.87%,and grain yield by 39.19%-51.21%.Moreover,shading imposed during grain filling stage also resulted in significant decreases in head rice rate,peak viscosity,breakdown and amylose content,the chalky grain rate,chalkiness(except Taiyou 871),setback and protein content increased,while the rice texture properties(excluded Yongyou1538)deteriorated.Compared with Taiyou 871 and ShenYou 26,the dry matter of YongYou 1 538 increased significantly after anthesis and its contribution rate under shading conditions increased by 43.39%-301.44%,33.30%-237.42% and 7.19%-179.87%,respectively.The dry matter,harvest index and grain setting rate at maturity were also significantly increased,and the final yield increased significantly by 25.73%-29.23%.[Conclusion]The higher dry matter after anthesis and its contribution rate of Yongyou 1538 provided more carbohydrates for grain filling under shading conditions during grain filling stage,thus reducing the effect of shading on yield and quality formation.Planting indica-japonica hybrid rice Yongyou 1538 as double cropping late rice in Jiangxi province could not only achieve high yield and stable yield,but also maintain better eating quality.更多还原