细胞质抗除草剂谷子遗传发育特点及应用研究

Genetics,Development and Application of Cytoplasmic Herbicide Resistance in Foxtail Millet

目的研究细胞质抗除草剂基因对谷子性状和发育的影响。方法利用细胞质抗除草剂谷子与敏感型谷子正反交和多代回交等方法,获得了同核异质杂交群体和近等基因系,比较其F1、F2、回交和复合杂交世代的群体差异和近等基因系的生长发育差异。结果具有抗除草剂细胞质的谷子苗期发育迟缓、抽穗晚,灌浆时间短;用其杂交获得的回交、复合杂交及F2的多数群体表现了生长弱势。但是具有细胞质除草剂抗性的谷子,在杂交F1代可产生较大的杂种优势;回交、复合交和F2代有较大的分离,并且个别组合表现了与敏感细胞质一样的丰产性。结论细胞质抗除草剂基因对谷子的生长和性状发育有影响,但利用杂交种可避免细胞质抗性产生的不利影响,获得丰产性;对抗性杂交群体和个体进行选择可达到预期效果。在对抗除草剂谷子选育时,应注重苗期发育快、根系发达、抽穗早、灌浆速度快的单株。把以上的研究结果应用于实践,获得了多个细胞质抗除草剂谷子的丰产杂交组合和品系。

[Objective] The effect of cytoplasmic herbicide resistant gene in millet plants was studied. [Method] The heterozygous populations and isogenic lines with homocaryotic alloplasmic genes were obtained by crossing and reciprocal crossing of cytoplasmic herbicide resistant plants with susceptive plants of foxtail millet. The characters of F1, F2, backcross and composite cross groups and the growth and development of isogenic lines were compared. [ Result] The cytoplasmic herbicide resistant gene slowed the development of seedling, delayed heading and shortened milking stage in foxtail millet plant. Yield capacity and main agronomic characters were all affected by the cytoplasmic herbicide resistant gene in most of the backcross, composite cross and F2 populations. However, there were stronger hybrid vigor in F1. The backcrosses, composite crosses and F2 populations were widely separated and some of them had good characters as that of susceptive groups. [ Conclusion ] The plant characters and development of foxtail millet were negatively affected by the cytoplasmic herbicide resistant gene. The authors proposed a method of using hybrid vigor to obtain high yield and avoid the negative effects of herbicide resistance cytoplasm in plant growth. The expected results could be obtained by selecting individuals in separated populations of fast developed seedlings, well developed roots, and with capacities of early heading and fast milking. Guided by the principal mentioned above, many high yield lines and hybrid crosses of foxtail millet with herbicide resistant cytoplasm were obtained.