Abstract: The dual-purpose genic male sterile line indica rice Pei'ai 64S and conventional rice cultivar Jingxian 89 were used as experimental materials. The mechanisms of fertility conversion and expression in the male sterile line were studied using PAGE to comparably analyse its changes of NAD^＋-MDH and AP isoenzyme during pollen mother cell formation, reduction division and pollen ripening stage at spikelet development period. Results indicated that Pei'ai 64S sown on 25 February, 10 March and 30 March in 1993 was all sterile. Their pollen abortion percentage was above 99. 7% and the seed setting rate was below 0. 3%. Pei'ai 64S sown on 1 August 1994 was fertile with a seed setting rate above 19%. Conventional rice cultivar Jingxian 89 sown at the same time could all obtain normal grains with a seed setting rate above 68%. Furthermore, the abortion of Pei'ai 64S sown in 1993 was markedly related with the decrease of NAD^＋-MDH enzyme activity in spikelet and anther during the polIen ripening stage. Its abortion was also closely related with the change of AP activity and isoenzyme components in the spikelet at pollen mother cell formation-reduction division stage. Pei'ai 64S sown in 1994 showed fertility which did not exhibit these changes. So we think that fertility expression of Pei'ai 64S could be related with fat metabolism at the initial stage in pollen development or its respiratory metabolism at the late stage of pollen development.

Key words: acid phosphatase, dual-purpose genic male sterile line, fertility expression, malate dehydrogenase, spikelet development

摘要： 以籼型两用不育系水稻培矮64S和常规稻粳籼89为材料，采用PAGE分析同工酶的方法，比较水稻幼穗发育过程中花粉母细胞形成期、减数分裂期和花粉完熟期NAD+-MDH和AP同工酶的变化，以期了解不育系的育性转换与表达机理。结果表明，在1993年2月25日、3月10日和3月30日三期播种的水稻培矮64S均表现不育，花粉不育度在99.7%以上，结实率在0.3%以下，1994年8月1日播种的培矮64S表现可育，结实率在19%以上，而同期播种的常规稻粳籼89均能得到正常结实，结实率在68%以上。同时发现1993年培矮64S的不育性在花粉完熟期与颖花及花药的NAD⁺-MDH活性的显著降低关系较大。在花粉母细胞形成期—减数分裂期与颖花AP的活性及同工酶组成的变化关系较密切。1994年表现可育的培矮64S与粳籼89相比不存在这种差异。由此可认为培矮64S育性表达可能与花粉发育前期的脂肪代谢以及花粉发育后期的呼吸代谢有关。

关键词: 两用核不育系, 幼穗发育, 苹果酸脱氢酶, 酸性磷酸酯酶, 育性表达