浙北地区单季晚粳稻直播栽培的高产途径研究

根据课题组2003—2005年掌握的地处浙北地区的嘉兴市的82块大田试验结果与测产田资料，进行统计分析，旨在探讨其高产途径。结果表明，有效穗数、每穗实粒数和千粒重对直播单季晚粳稻产量具显著正效应，其中正效应最大的为每穗实粒数，有效穗数其次。在数据分析基础上，提出浙北地区单季晚粳稻直播栽培的高产途径为：在争取一定有效穗数基础上，应把增加每穗实粒数作为主攻方向，同时提高灌浆质量适当增加粒重。结合生产实践，在目前现有品种条件下，浙北地区单季直播晚粳稻9500 kg/hm2左右产量水平的合理结构可能为：基本苗约为125万/hm2，最高苗630万/hm2，有效穗数450万/hm2，每穗总粒数＞100粒，每穗实粒数90~95粒，千粒重26g左右。

Study on the Strategies of High Grain Yield for the Direct Seeding Single Late Japonica Rice in North Zhejiang

Based on the survey data in 82 fields of direct-seeded late Japonica rice at Jiaxing in North Zhejiang, statistically analyzed by means of multivariate regression analysis and path-coefficient analysis, the ways for high yield of direct-seeded late Japonica rice in North Zhejiang Province were studied. The results showed that the effective panicle per hm^2, filled grain number per panicle and 1000-grain weight had positive effects on yield, and filled grain number per panicle was the largest and the second was the effective panicle per hm^2. For obtaining higher yield of direct-seeded late Japonica rice, it is necessary to develop the filled grain number per panicle and increase the 1000-grain weight by improving the grain- filling quality on the basis of obtaining a suitable effective panicle number which will insure high yield. It was suggested that the yield component for 9500 kg/hm^2 yield of the direct-seeded late Japonica rice in North Zhejiang Province might be 125-104/hm^2 of planting seedling, 630-104/hm^2 of peak seedling, 450- 104/hm^2 of effective panicle, above 100 grains of total grain number per panicle, 90-95 grains of filled grain per panicle and 26 g of 1000-grain weight under the present practice.