夜温升高对双季水稻物质生产与养分吸收的影响

Effect of increased nighttime temperature on dry matter production and nutrient absorption in double cropping rice

利用两间玻璃室不同的夜间温度条件,研究了水稻生长期间夜温升高对双季早、晚稻物质生产和养分积累的影响。结果表明:夜温升高对双季早稻的生物产量没有影响,但可显著提高晚稻生物产量。早稻穗分化前夜温升高可增加物质积累量,而穗分化后则减少物质积累量;夜温升高减少晚稻幼穗分化至抽穗期间的物质积累,而增加其他生育期的物质积累。夜温升高加速早稻剑叶衰老,而对晚稻无显著影响。夜温升高对水稻氮素积累影响较小,对磷、钾积累影响较大。其中,播种至幼穗分化夜温升高有利于早稻稻株的养分积累,而幼穗分化后不利于养分积累;夜温升高不利于晚稻播种—抽穗的养分积累,而有利于抽穗后的养分积累。试验表明,夜温升高对不同季水稻及水稻不同生育期物质生产与养分吸收的影响存在差异。

An experiment was conducted under different glasshouse conditions to determine the effect of nighttime temperature increase （NTI） on dry matter production and nutrient absorption in double cropping rice. No significant effect of NTI on dry matter production in early rice is noted. However, NTI significantly increases dry matter production in late rice. In early rice, NTI enhances dry matter accumulation before panicle differentiation, but decreases it after that. In the case of late rice, dry matter accumulation is enhanced by NTI, except during panicle differentiation to heading. Flag leaf senescence in early rice is accelerated by NTI, but no similar effect is noted in late rice. There is less obvious impact of NTI on total nitrogen accumulation than on P and K accumulation. In early rice, NTI only benefits crop nutrient absorption before panicle differentiation, but after that NTI inhibits nutrient absorption. However, the opposite tendency is observed before and after heading in late rice. The study therefore suggests that the effect of NTI on dry matter production and nutrient absorption is different between early and late rice, and among growth stages.