一个新的小麦黄化突变体的遗传研究

摘要: 通过对冬小麦“西农1718” 自然黄化突变体多年连续自交、与突变亲本回交以及与其他基因型进行正反交, 研究突变性状的遗传规律。观察统计发现, 突变体中金黄株发育至抽穗－开花期前后死亡, 黄-绿株自交后代表现为1金黄株︰2黄-绿株︰1绿株, 绿株自交后代不再分离; 黄-绿株与突变亲本回交及与其他基因型正反交, 后代均表现为1黄-绿株︰1绿株。遗传分析表明, 该小麦黄化突变体是由一对核基因控制的不完全显性遗传, 其中, 金黄株是纯合体(au/au), 表现为致死, 黄-绿株为杂合体(Au/au), 绿株为纯合体(Au/Au)。

Genetic analysis of a novel aurea mutant in wheat

Abstract: A novel spontaneous chlorina mutation of wheat (Triticum aestivum L.) was found in 2000. Three types of phe-notypes, i.e., green plant, intermediate yellow-green plants (or chlorina), and yellow plant (aurea), were observed in the selfed progenies of the mutant. The aurea plants usually died before heading stage, and the intermediate plants were viable but less vigorous and developed later than the green plant. The mutant wheat was analyzed genetically after self-pollination and crossing with normal green plants. Selfing the M1 plant (chlorina) results in 1:2:1 segregation ratio of aurea : chlorina : green plants. The progenies of M1 green plants were all green. The test cross between a chlorina plant and a normal plant (as male or female) gave a 1 normal green: l yellow-green segregation ratio. The result can be explained on the assumption that the aurea is homozygous for au and the chlorina heterozygous for Au. Based on these findings, this mutant is controlled by a partial dominant nucleus gene. The genotypes of aurea, chlorina, and normal plants are au/au, Au/au, and Au/Au, respectively.