小麦矮秆圆粒突变体的鉴定与分析

Identification and Analysis of the Dwarf-Spherical Grain Mutant W98

小麦的子粒形态性状和株高与小麦的产量密切相关,是育种的重要选择目标性状。本研究通过对小麦品种偃展1号(YZ1)EMS突变体W98的农艺性状的调查与分析,发现W98的株高只有24 cm,而野生型YZ1的株高是73 cm。突变体株高的变异是由每个节间长度变短造成的,而非节间数目减少所致。相关分析表明矮秆与圆粒性状呈显著相关。利用高秆长粒的墨西哥品种10th12与突变体W98配制杂交组合,获得1544个F2∶3单株(株系),通过对分离群体的遗传分析,发现圆粒性状是由1对不完全显性基因控制的。赤霉素(GA)与油菜素内酯(BR)激素敏感性试验表明:野生型和突变体都对GA处理不敏感;不同浓度BR的展叶试验表明野生型对BR不敏感,而突变体W98对BR敏感。

Wheat grain morphology and plant height are important target traits in wheat breeding history and they are significantly correlation with wheat yield performance. In this study, the wheat dwarf-spherical grain mutant W98 identified from Yanzhanl EMS （ethylmethyl sulfide） mutant library was analyzed. The results showed that the plant height of the mutant W98 was 24 cm,whereas the wild type YZ1 was 73 cm. W98 reduced plant height by decreasing the length between internodes, not reducing of the number of nodes. Correlation analysis showed that the two traits-dwarf and spherical grain were significantly correlated. Genetic analysis indicated that the spherical grain phenotype was controlled by a single incompletely dominant gene by using 1544 F2：3 progenies generated from the cross of the long grain Mexico synthetic hexaploid wheat 10th12 with the mutant W98. Sensitivity test of GA and BR indicated that both of the wild type and the mutant were not sensitive to GA,while the mutant was sensitive to BR and the wild type was not by using the wheat leaf unrolling assay with different BR concentrations.