晚季杂交水稻群个体协调栽培技术的研究

STUDY ON THE CULTURE TECHNIQUE OF HARMONIZING THE RELATIONSHIP BETWEEN MASS AND INDIVIDUAL IN LATE-SEASON HYBRID RICE

本研究比较了晚季杂交水稻上进行的两种栽培措施。其区别在于:新栽培措施的施氮比例为5:2:2:1(即基面肥50％,分蘖肥20％,保花肥20％,粒肥10％),而常规栽培措施的施氮比例为7:3:0:0;新栽培措施在分蘖盛期采用灌深水控蘖而常规栽培措施则采取传统的搁田控蘖措施。试验结果表明,新栽培措施对3个不同穗型的供试组合均有明显增产效果,其中大田和盆栽试验中分别比常规栽培措施增产6.2％～10.7％和10.5％～12.6％。新栽培措施能增产的机理有:(1) 群体得到有效控制,成穗率提高;(2) 冠层结构合理,株型得到改善;(3) 个体生产力得到充分发挥,物质生产和积累多,茎鞘物质转运率高,经济系数大。

The main differences between the two culture techniques lie in the following two respects. Firstly, the whole nitrogen fertilizer was apportioned as 5∶2∶2∶1(50％ as basic fertilizer, 20％ at the tilling stage, 20％ at the sex differentiation stage and 10％ at fully heading stage) in the new culture technique, and 7∶3∶0∶0 in the normal culture technique. Secondly, for tiller control, about 15cm deep-water irrigation was carried out at the peak tillering stage in the new culture technique, while draining was done in the normal culture technique.The results of the experiments showed: Compared with the normal culture technique, the new culture technique could increase the grain yield of all the three tested late-season hybrid-rice combinations by 6.2～10.7 in the field experiment and by 10.5～12.6％ in the pot experiment.Several reasons were found to explain why the new culture technique could increase the yield greatly. Firstly, the population size was effectively controlled and the percentage of productive tillers was significantly increased. Secondly, the canopy structure of the mass became more reasonable and the plant stand was improved. Thirdly, the growth capacity of the single plant was much improved. Finally, the transportation proportion of photosynthates from leaf sheath to the panicle increased, which raised the harvest coefficient.