高海拔地区杂稻母本撒直播制种技术研究

Broadcast Sowing Technique of Female Parent in Hybrid Rice Seed Production at High Elevation Areas of Guizhou

对高海拔地区杂交水稻母本撒直播制种技术研究表明，具有明显的增产优势。其增产的主要原因是增加了单位面积有效穗和总颖花数，提高了异交结实率，比母本移栽的结实率高５．９％。生长发育的主要特点是：分蘖早，分蘖节位低，抽穗整齐，播始历期减少５ｄ。在高海拔地区运用配套技术，一般产量可达５ｔ／ｈｍ２，最高产量达５．７０１３ｔ／ｈｍ２。

Broadcast sowingtechniques ofthe femaleparentin hybridrice seed productionwere studied in high elevation areas of Guizhou during 1995～1996 The results showed that the broadcast sowing techniques for the female parent had significant increasing heterosis,compared with the transplanting maternal cultures The causes of increasing yield were that the effective panicles and spikelets and outcrossing rate were together increased Outcrossing rate increased by 5 9% higher than that of the transplanting maternal The main characters of growth were that direct seeding for female parentresulted in earlier tillering,shorter heading duration and less 5 days from seeding to initial heading Since the techniques were applied in Meitan county of Guizhou,yield of hybrid rice seed production has been raised to 5 t/ha with the highest up to 5 7013 t/ha