杂交水稻制种田后期喷施植物生长激素九二○是解除母本苞颈,调节花期,增加异交结实,提高制种产量的一项关键技术,尽管制种生产上对科学喷施九二○试验研究和经验介绍很多,但不少制种单位和农户在实际使用过程中仍存在剂量掌握不准,时机把握不当,配套措施不全的问题,这就影响了九二○喷施效果的发挥,增加制种成本,导致制种的综合经济效益下降。笔者在本市近年来大面积汕优63制种实践 Spraying plant growth hormone in hybrid rice farming late 1990 is a key technology to eliminate maternal necks, regulate flowering period, increase outcrossing and increase seed production. Although seed production is spurting to science, There are many experimental research and experience introduction, but many seed production units and farmers in the actual use of the process still does not grasp the dose, the timing of misconduct, supporting the problem of incomplete, which affected the spraying effect of 920, Increase the cost of seed production, resulting in reduced overall economic benefits of seed production. Author in the city in recent years a large area Shanyou 63 seed production practice