一个水稻畸形颖壳突变体ah的鉴定及其突变性状的遗传分析

水稻畸形颖壳突变体ah是双胚苗品系W2555中自然突变产生的。该突变体的内外稃畸形,退化;雄蕊雌蕊化,雌蕊败育;浆片同源转化为类内外稃的结构,推测该突变体可能影响B功能基因的正常发育。与野生型相比,突变体的小穗分支稀疏,每级枝梗上颖花数目减少,一般为4～6朵;小穗顶端的颖花经常不能成熟,表现为颖花始终泛白,不能转绿,因此该突变也影响花序分生组织的发育。进一步的研究证明,该突变体的发育受外界环境的影响。突变性状的遗传分析表明,该突变体由单隐性基因控制。

Morphological, Anatomical and Genetic Analysis for a Rice Mutant with Abnormal Hull

A mutant with abnormal hull was first discovered from a twin-seedling strain W2555 in rice(Oryza sativa L.).The mu- tant had sparse branches and decreased number of florets from the base to the peak.Frequently,the florets at the top of the panicle did not develop completely.The underdeveloped florets often showed slender and white in their life cycle.Genetic analysis indi- cated that the mutant traits were controlled by a single recessive gene(temporarily designated as ah).ah gene controlled the devel- opment of inflorescence meristem and the flower organ.The florets of mutant showed degenerated lemma and palea.Stamens and lodicules were homeoticly transformed into pistils and palea/lemma-like structures,respectively.It seemed that ah mutant pheno- types of the homeotic conversions in lodicules and stamens were very similar to that of the B loss-of-function spw1 gene reported previously in rice.