【摘要】 利用携有和不携有广亲和基因的两类籼粳亚种间杂种为材料,观察其孢子体和配子体的发生过程,明确杂种雌雄配子体败育的特征。结果显示:花粉和胚囊的败育均与小孢子和大孢子第一次有丝分裂异常有关,前者表现为小孢子间有丝分裂不同步,导致部分花粉不能正常成熟和败育;后者表现为大孢子有丝分裂异常(包括一些大孢子有丝分裂的延迟),在成熟的胚珠中不能形成胚囊。利用整体染色技术直接决定了杂种胚囊的育性。不同于携有广亲和基因的杂种,不具广亲和基因的杂种胚囊的败育直接导致了小穗的不孕。花粉的败育和不正常的裂药在两类杂种中通过影响柱头上花粉的萌发量间接控制小穗的受精。更多还原

【Abstract】 F1 plants of indica×japonica with or without wide compatible gene(WCG) were used toinvestigate the male and female sporogenesis and gametogenesis. Pollen and embryosac degeneration wasobserved in crosses without WCG, which were respectively characterized by asynchronous mitosis of mi-crospores that lead to some immature and aborted pollen grains and abnormal mitosis of megaspores(includ-ing slowdown in some megaspores mitosis) that failed to produce embryosac in mature ovule. Embryosacfertility was directly determinated by a whole stain-clearing method. Unlike F1 plants with WCG, thespikelet sterility of F1 plants without WCG could be caused directly by embryosac degeneration. Pollensterility and abnormal anther dehiscence which determined the number of pollen grains germinated on stigma and affected indirectly the fertilization of spikelets in some crosses with or without WCG.更多还原