水稻群体光合速率和茎鞘贮藏物质与产量关系的研究

 采用汕优 ６３和盐粳１８７品种（组合），通过设置前后期不同氮素配比，对水稻群体光合速率（ＣＡＰ）和茎鞘贮藏物质与产量的关系进行了研究。结果表明，在抽穗后ＣＡＰ随生育进程而逐渐降低。汕优６３以６：４配比ＣＡＰ较高。上３茎鞘物质干重变化呈“Ｖ”字型，在穗后２３ｄ左右达最低值，其中以顶三茎鞘物质输出最多。ＣＡＰ与群体质量指标、穗后物质生产和产量的关系除穗后２３ｄ左右外比较密切，穗后２３ｄ茎鞘贮藏物质大量输出。

Relations Between Canopy Apparent Photosynthesis and Store Matter in Stem and Sheath Between and Yield and Nitrogen Regulations in Rice

From 1996 to 1997,the field experiments on the ratio of basal and tillering N fertilizer applied in early growth stage to Panicle-spikelet N fertilizer applied in late growth stage with SHANYOU 63 and YANJING 187 were carried out ,and the effects of N fertilizer application on Canopy Apparent Photosynthesis (CAP) ,single stem-sheath weight and export percentage of stem and sheath matter were studied. The results indicated that CAP decreased gradually with crop development during ripening stage. The optimum ratio of N fertilizer applied in early and late growth stage was 6 4,it had higher CAP than other treatments. The changes of stem and sheath weight showed a single peak curve after heading, minimum weight occured around 23 days after heading. The maximun export percentage of rice was the third stem and sheath from top. The CAP correlated positively with yield and population quality index at ripening stage except at 23 days, perhaps something has to be done with plenty of matter export from stem and sheath at this moment.