一个化学诱变的小麦斑点叶突变体的生理和遗传分析

Physiological Characteristics and Genetic Analysis on a Spotted-leaf Wheat Derived from Chemical Mutation

通过EMS诱变普通小麦品系H261,获得一个稳定遗传的斑点叶突变体LF2010。自然条件下,该突变体在三叶期叶片基部第一片叶最先出现黄色斑点,随着植株生长从基部老叶片到上部新生叶片依次出现黄斑,最后叶片上斑点逐渐增多并扩散到全片叶、叶鞘、颖壳和麦芒。斑点部位不存在细胞死亡,斑点性状的表达受光照和温度诱导,突变体的色素含量、光合速率随着斑点的出现而显著下降。突变体的株高、有效穗数、单株产量、穗长、结实率和旗叶长等农艺性状显著下降,但是千粒重和旗叶宽却与野生型无差异。将突变体与正常绿色品系杂交,对其F1、F2和BC1代的遗传分析表明,LF2010的突变性状由1对隐性核基因控制。

A light and temperature affected spotted-leaf mutant LF2010 （Triticum aestivum L.） was obtained from a mutagenic treatment with EMS on a wheat line H261. The bright yellow spot became evident once the third leaf will expanded, then covered later leaves and leaf sheaths of the whole plant including tissues of spike. The mutant plants differed from normal plants in terms of total chlorophyll content and net photosynthetic rate once symptom appeared on the leaves. The plant height, spike length, spike number per plant, grain weight per plant, grain number per spike, seed setting rate, and flag leaf length were lower in the mutant than in the wild type. However, the 1000-grain weight and flag leaf width of the mutant had no significant difference with those of the wild type. Genetic analysis based on F1, F2, and BC1 populations revealed that the yellow spot trait was controlled by a single recessive gene.