水稻不育系紫A的开花习性及异交结实性

Flowering Habit and Out-cross Characteristics of Purple A,a Rice Male Sterile Line

为了掌握新选水稻三系不育系紫A的异交特性，对其开花习性及异交结实性进行了初步研究。结果表明：花时集中在9：30-16：00，11：30时达到开花高峰期，午前开花率占68．2％；颖花张颖角度变幅为20°～29．4°，开闭颖历时9．5h；单穗开花高峰期为始花后的3～6d；柱头较大且在施用“九二0”情况下外露率高达79．88％，人工辅助授粉的情况下，紫A的异交结实率为73．69％，自然授粉的异交结实率仅为59．65％，变化幅度大且异交结实率受外界环境影响较大。

In order to hold out-crossing characteristics of Purple A, a new rice male sterile line, The results from studying the flowering habit and out-cross characteristics of it, showed that its flowering time was from 9：30 Am to 16：00 Pm, the flowering peak was at 11： 30, the forenoon flowering rate was 68.2% ,the glume open angle varied from 20° to 29.4°, the glume opening and closing period lasted 9.5 h, the flowering peak period of single spike was 3-6 d after its first flowering, the stigma exsertion rate was up to 79.88% under applying Gibberellin （GA3）, the out-crossing setting rate was 73.69% under artificial supplementary pollination, the out-crossing setting rate was only 59.65 % under natural pollination and its change range and out-crossing setting rate were affected by environmental factors.