外源GA3、ABA对杂交水稻亲本穗上发芽的生理影响

摘要

Hybrid rice parent line V20B was used as experimental material, and effect of exogenous GA3 and ABA on physiological characters of preharvest sprouting of hybrid rice in field was studied. The results showed that exogenous GA3 led to the change of endogenous GA3 and caused increase of the ratio of GA3/ABA, α-amylases activity and soluble sugar content. GA3 application also enhanced starch decomposition, broke seed dormancy and led to early preharvest sprouting. Exogenous ABA treatment on V20B decreased preharvest sprouting, increased endogenous ABA content and enhanced seed dormancy. The exogenous ABA decreased endogenous IAA content.%以杂交水稻亲本V20B为材料,研究了外源GA3、ABA处理后对杂交水稻稳上发芽的生理生化变化.结果表明,外源GA3作用改变了内源GA3水平,提高了GA3/ABA比值、α-淀粉酶活性和可溶性糖含量,使淀粉类物质降解加速和田间种子不经休眠直接在穗上发芽.经外源ABA处理后,V20B的穗芽率明显降低,内源ABA含量提高,促进了种子的休眠,抑制了穗上发芽；外源ABA降低了子粒中内源IAA含量.