晚粳、早籼光敏核不育水稻幼穗分化后光周期效应的比较

Comparison of Photoperiodic Effects of Panicle Development After Panicle Initiation Between Late Japonica and Early Indica Photoperiod sensitive Genic Male sterile Rice (PGMR) Lines 

报道了日长对不同晚粳（Ｏｒｙｚａｓａｔｉｖａｓｕｂ．ｊａｐｏｎｉｃａ）及早籼（Ｏ．ｓａｔｉｖａｓｕｂ．ｉｎｄｉｃａ）水稻幼穗发育的影响。发现在晚粳中，二次枝梗期之后所给予的长日处理除延迟幼穗分化进程外，还会影响颍花的发育，表现为颍花密度及结实率下降。而早籼稻中则无明显的类似效应。因此日长对幼穗发育的影响与日长对幼穗分化诱导的影响有一定的相关性。同时，长日对晚粳幼穗发育的影响与引起光敏不育表现的时期相同，表明光敏不育水稻的雄性不育是该突变体雄蕊发育对长日抑制幼穗发育影响的一种特殊反应。

For understanding the mechanism of photoperiodic sensitive male sterility in rice (Oryza sativa L.). The authors have studied the day length effects on the rice panicle development after the initiation of the secondary branch primordia (SBP). It was found that the long day illumination after the initiation of SBP not only delayed heading, but also affected the panicle morphology of late japonica rice lines. These effects were not seen in the early indica rice lines. The similarity of the day length effects after SBP and before the panicle initiation, as well as the synchronization between the above mentioned effects and the one caused male sterility of PGMR, supported the hypothesis that the photoperiodic sensitive male sterility in PGMR is consequent upon the failure of male organ development response to the long day stress by the mutation.