关键词: 周麦22号, 甲基磺酸乙酯（EMS）, 抗穗发芽, 突变体, 农艺性状, 种质资源

Abstract: Aiming at the serious shortage of pre⁃harvest sprouting（PHS）⁃resistant germplasm and cultivars in the Huang⁃Huai wheat region，a mutant library was constructed using Zhoumai 22 by ethyl methanesulfonate（EMS） mutagenesis.PHS⁃resistant mutants with excellent agronomic traits were screened through PHS resistance identification and agronomic trait analysis，so as to provide elite germplasm resources for PHS resistance breeding. The results showed that a total of 36 mutants with moderate or higher PHS resistance were identified from 1 189 mutants，which exhibited large variation coefficients and abundant variations in plant height，effective tiller number per plant，spike length，grain number per spike，1 000⁃grain weight，and grain yield per plant.Among the 36 PHS⁃resistant mutants，23 mutants showed no significant difference in plant height compared with wild type（WT），16 mutants had no significantly lower grain yield per plant than WT，and eight mutants had no significantly lower 1 000⁃grain weight than WT. Twelve mutants（SFY04，SFY05，SFY06，SFY13，SFY15，SFY18，SFY21，SFY22，SFY23，SFY24，SFY27，and SFY33）performed well in both plant height and grain yield per plant. Among them，SFY05，SFY13，SFY18，SFY22，SFY24，and SFY27 showed moderate or higher PHS resistance in two cropping years.Among the 16 mutants with no significantly lower grain yield per plant than WT，two mutants（SFY30 and SFY04）had no significant difference in 1 000⁃grain weight compared with WT，retaining the large⁃grain characteristic of WT.Among them，SFY30 was a dwarf mutant with large grains. Grain yield per plant was extremely significantly positively correlated with effective tiller number per plant.The 36 PHS⁃resistant mutants were clustered into four groups.Group Ⅰ contained 12 mutants including SFY03 and so on，with relatively balanced comprehensive traits. Group Ⅱ contained 20 mutants including Zhoumai 22 and so on，with obvious high⁃yield characteristics. Group Ⅲ contained four mutants including SFY15 and so on，belonging to the grain⁃number⁃per⁃spike superior type. Group Ⅳ had only one mutant（SFY19），which was extremely prominent in plant height and spike length（both the highest），belonging to a special ecotype or genetic extreme material. In conclusion，13 PHS⁃resistant mutants with excellent agronomic traits were developed and identified，including 12 mutants with superior performance in both plant height and grain yield per plant，and one dwarf mutant with large grains.Among them，six mutants（SFY05，SFY13，SFY18，SFY22，SFY24，and SFY27）possessed stable moderate or higher PHS resistance.

Key words: Zhoumai 22, Ethyl methanesulfonate（EMS）, Pre?harvest sprouting resistance, Mutant, Agronomic traits, Germplasm resources