双季杂交稻“肥促水调”栽培技术的应用

Application of "Fertilizer-promoting Water - controlling" Cultural Technique in Double Cropping Hybrid Rice

选用优势强、品质优的杂交组合，早季中熟搭配晚季迟熟组合，培育壮秧，控制分蘖肥用量，增大后期施肥量，超前搁田控制苗峰，在一定穗粒基础上，实现总粒数、实粒数和经济系数的大幅度提高，从而提高产量．

The technique called ＂Fertilizer-promoting Water-controlling＂ was demonstrated in 5.02 ha double cropping hybrid rice fields in 1991 - 1992. The yearly rice yield was 15.08- 15.68t/ha, 15.1% - 36.0% higher than that in 1990 when the conventional cultural management was used. This new technique was extended to an area of about 0.13 million ha double cropping hybrid rice fields in Cangnan County, Wenzhou, and an increase of 25.348 thousand ton paddy was obtained. The main points of the technique includes： （1） Ferti- lizer management on the principle of heavy basal fertilizer, no or a little tillering fertilizer and proper spikelet-promoting fertilizer. The spikelet-promoting fertilizer is generally applied when the leaf next to flag leaf emerges with 45 - 75kg urea per ha and proper amount of potassium fertilizer. The toltal amount of fertilizer applied should be limited within 187.5kg N/ha for the early rice crop, 225kg N/ha for the late rice crop. （2） Water management, When the number of tillers rises to 65% of the expected number of panicles the standing water should be drained away and the field be dried to control excessive tillers, and the reirrigation with shollow water should be done a little advance of the booting stage. （3）Other neocessary techniques i.e. choosing hybrid combinations, with high yielding ability and good grain quality and arranging medium-maturing ones for the early scason cropping and late-maturing ones for the late season cropping; raising vigorous seedlings; integrate control of diseases and insect pests.