钾营养对不同水稻基因开型物质生产和光合作用的效应

在大田条件下，研究了低钾土壤中钾营养对水稻不同品种谷粒产量，干物质积累特性及光合作 用的效应。结果表明：在不施钾条件下，低钾敏感品种谷粒产量显著降低，抽穗后２周内ＲＧＲ， ＣＧＲ和 ＮＡＲ均低。而低钾耐性品种在低钾营养条件下有高的产量，这与ＮＡＲ高、冠层ＬＡＩ的分布合适以及较 低的大田消光系数和一天中各时间的光合速率高有关，试验还发现在群体条件下黄熟期水稻冠层有明 显的光合“午睡”，低钾敏感品种无钾供应时“午睡”加剧。

The effect of potassium nutrition on dry matter production and photosynthesis of different genotype in rice.

This research was conducted to investigate the effect of potassium nutrition on grain yield , char- acteristic of dry matter accumulation and photosynthesis in low-potassium field. The results showed, in case of no-potassium application, grain yields of the cultivars sensitive to low potassium significantly de- creased and their RGR, LAI , CGR and NAR were all low during two weeks after heading, however, those of the cultivars resistant to low potassium were similar between no-potassium application and potassi- um application. Higher yield of the cultivar resistant to low potassium was relative to their higher NAR and photosynthetic rate during the whole day and suitable distribution of LAI after heading. The result also showed canopy in rice population had significant midday-depression of photosynthesis and the midday- depression of cultivars sensitive to low potassium were deeper than that of cultivars resistant to low potassi-um.