野鸢尾和射干种间杂交F_2代主要性状变异分析

通过观测野鸢尾(Iris dichotoma)×射干(I.domestica)杂交F2代群体(n=61)中每一个体的株高、花径、花数、花色和彩斑等14个表型性状,对F2代与双亲性状差异、群体性状变异、主要性状间遗传相关性及花色遗传变异等方面进行分析,以明确F2群体性状变异特点,指导夏季开花鸢尾育种实践。结果表明:F2代12个性状中,8个性状的观测值居于双亲之间;除花朵直径和花朵数量外,花葶长等10个性状基本均呈正态分布,属多基因控制的数量性状;性状之间存在一定相关性,外花被长与内花被长和外花被宽与内花被宽的相关度最高,相关系数分别为0.821和0.734,趋于连锁遗传;对颜色性状的分析结果表明花色和花瓣彩斑的遗传由不同基因调控,但都是由多个基因共同控制。野鸢尾×射干F2代群体的花朵直径、花朵数量、花葶长及花色变异丰富,利于大花、多花、花葶矮生和奇异花色的优良单株的选择。

Variation analysis of important ornamental traits in F2 hybrids of Iris dichotoma and I. domestica

We observed and measured14 traits such as scape length,flower diameter,number,color and the colored sectors in each individual of 61 F₂ hybrid population of I.dichotoma×I.domestica,scape length,flower cliameter,number of flowers,flower color and colored sectors et al.The aims were to explore the variation traits and direct the breeding work in Iris.Four aspects of phenotypic difference between F₂ hybrids and two parents,morphological traits variability,the correlation between the traits and color variability were analyzed.The results showed that 8 traits from 12 in F₂ generation were among the parents.Ten traits had better normal distribution but not the flower diameter and flower number.It might imply that the ten were quantitative traits controlled by polygenic.There was a correlation among the 12 traits.The correlation coefficients of outer tepal length and inner tepal length,outer tepal width and inner tepal were highest,0.821 and 0.734 respectively,which suggested a linkage inheritance.Two color traits were controlled by multiple genes.In F₂ hybrids,the variation were rich in flower diameter,flower number,scapes length and flower color,which might be conducive to the chosen of excellent varieties with larger diameter,more flowers,dwarf scape and novel flower colors.