杂交中稻小穗型组合适宜强化栽培的因素分析

以18个杂交中稻组合为材料,分别进行强化栽培和传统栽培两组试验,研究了组合类型与强化栽培增产作用的关系。结果表明:强化栽培比传统栽培的稻谷增产量与组合间着粒数呈极显著负相关关系。其原因在于,小穗型组合在强化栽培条件下,虽然有效穗数仍有所下降,但因着粒数大幅度提高,以致总颖花量增加,结实率较稳定,最终表现为比传统栽培增产。与此相反,大穗型组合在强化栽培条件下,因分蘖力较小穗型组合弱,有效穗较传统栽培明显下降,结实率因库源矛盾加剧较传统栽培大幅度下降,尽管着粒数增加较多,也不能弥补因有效穗和结实率显著下降所致的减产。传统栽培条件下的着粒数不超过170粒的小穗型组合可作为强化栽培选择品种的参考指标。

Preliminary analysis of the hybrids with smaller panicle in the system of rice intensification

Grain yield and yield component traits of 18 rice hybrids were evaluated under the system of rice intensification(SRI) and traditional cultivation(CK).The increasing yield effect of SRI to CK was very significantly and negatively correlated with the grains per panicle of hybrids.The hybrids with smaller panicle had positive yield effect under SRI because the grains per panicle and total number of spikelets increased.The hybrids with bigger panicle under SRI,however,showed negative yield effect due to largely declining in effective panicle and seed set percentage.A suggestible criterion is that the hybrids with grains per panicle less than 170 in CK,may more be suitable to SRI.The relation between soil fertility level and SRI effect was also investigated.