大豆多小叶类型遗传规律初探*

利用合丰25×东农7296系谱法经5个世代选育获得多小叶突变体,并以其作为父本分别与4个小叶正常的栽培大豆配制杂交组合的F1、F2为试验材料,进行多小叶类型的遗传分析。结果表明:小叶数正常的不同大豆亲本与多小叶大豆杂交(3叶×5叶),F1全部植株均表现为5叶,说明5叶性状是受显性核基因控制;不同组合3片叶、3+4片叶、3+5片叶、3+4+5片叶、4+5片叶和5片叶类型组成遗传分离模式存在显著差异,而在3片叶和>3片叶的遗传分离模式相同。杂交F2单株复叶为3片叶和>3片叶的个体分离的比例呈1∶3,符合1对显性单基因的遗传规律。因此,该多小叶突变体牡5796-3的复叶数受1对显性基因控制,该多小叶突变体可作为新种质用于大豆遗传育种及基因克隆和功能研究。

Primary Research on Heredity Rule of Multi-leaflet Mutant in Soybean

Genetic analysis of multi-leaflet trait were conducted by four crosses from 4 normal female parents with 3-leaflets and one mutantal male parent with five-leaflet which is derived from 5th selfbred of cross Hefeng25×Dongnong7296. All leaves of F1 individual have 5 leaflet in 4 crosses, which indicated that 5-leaflet is dominantly controlled by nuclear genes. The segaration mode of 3-leaflet, 3+4-leaflet, 3+5-leaflet, 3+4+5-leaflet, 4+5-leaflet and 5-leaflet were different according to crosses in F2. While the inheridtary pattern of 3-leaflet and >3-leaflet were coherent in various genetic background with a segarating ratio of 1:3, which means that leaflet traits follows one dominant gene inheridity. Leaflet were controlled by one dominant gene and the new soybean mutant germplasm Mu5796-3 can be used in soybean breeding and gene cloning.