用~(14)CO_2示踪研究汕优10号不同类型群体的成穗率及光合效率

以汕优１０号为材料，在齐穗期采用１４ＣＯ２同化标记，研究了汕优１０号不同类型群体的成穗率和光合效率。还就群体成穗率和光合强度，群体净同化率和成穗率，群体的呼吸消耗和光合产物分配比例与产量的关系，以及提高成穗率的途径作了探讨。

Studies on the Rate of Panicle-bearing Tillers and Photosynthesis Efficiency of Shan-You 10 with Different Population Types by ~(14)CO_2 Tracing

With hybrid rice Shan-You 10 as trial material, the rate of panicle-bearing tillers and photosynthesis efficiency of diffierent population types were studied by 14CO2 tracing at full heading stage. The higher the rate of panicle-bearing tillers was,the stronger the photosynthesis intensity of leaf after heading stage was, and so was the net assimilation rate of population; As the rate of panicle-bearing tillers being increased; the respiration consumption of population was reduced, but the rate of photosynthates distributed to ears was increased , so this was more useful to accumulate dry matter. In this paper the relationship between rate of panicle-bearing tillers and grain-yield and the ways to increase rate of panicle-bearing tillers were also discussed. In order to markedly raise the rate of panicle-bearing tillers of hybrid rice with strong tillering capacity, it is better to take effecitive measures to control tillering. A study on the sensitive stage of tiller shoots to the environment made it possible to find the optimum time to control tillering. Experiments showed that if per mu 200-220 thousand productive panicles remained stable, the rate of panicle--bearing tillers might be increased by 15%-25%, and the grain yield by 10%-20%.