金钟连翘与东北连翘种间杂交F1代表型性状遗传分析

Genetic Analysis of Phenotypic Traits in F Hybrids of Forsythia intermedia×F.mandschurica

为了阐明连翘属植物主要观赏性状和抗寒性的遗传特点,以金钟连翘品种‘Lynwood’(Forsythia intermedia‘Lynwood’)和东北连翘(F.mandschurica)杂交获得的F1代群体为研究对象,对杂交群体的花冠口直径、花裂片长度、抗寒性等12个表型性状进行测定,并对这些性状进行相关性分析和混合遗传模型分析。结果表明:金钟连翘与东北连翘杂交群体的表型性状变异丰富,各表型性状均出现大于高亲或小于低亲的超亲个体。除花裂片长度、花裂片宽度、叶片长度外,其他性状的变异度均超过15%,达到中等水平以上。各性状之间存在一定的相关性,其中抗寒性与着花密度呈极显著正相关,与花冠口直径、植株冠幅呈极显著负相关关系。混合遗传模型分析显示,花裂片长度、花裂片宽度、花裂片长宽比、叶片长度、叶片宽度、叶片长宽比、当年生枝条长度、抗寒性由微效多基因控制,花冠口直径和植株冠幅由一对加性—显性主基因控制,着花密度由两对加性—显性主基因控制,株高由两对等加性—显性主基因控制。花冠口直径、冠幅、着花密度和株高的主基因遗传力分别为76.05%、60.3%、72.22%和64.75%。研究结果为定向培育综合性状优良的连翘新品种提供了依据。

In order to clarify the genetic characteristics of main ornamental traits and cold resistance ofForsythia,the F1 hybrid obtained from Forsythia intermedia‘Lynwood’×F.mandschurica was taken as material.The 12 phenotypic traits such as corolla diameter,corolla lobe length and cold resistance were measured,andcorrelation analysis and mixed genetic model analysis of these traits were carried out.The results showed that F1 population varies significantly and the new phenotypic traits precede parents.Except for corolla lobe length,corolla lobe width and leaf length,the coefficient of variation of other phenotypic traits was more than 15%respectively,reaching a medium level or above.There was a certain correlation between the phenotypic traits,and the cold resistance was significantly positively correlated with flower density,but was significantlynegatively correlated with corolla diameter and crown width of the plant.Mixed genetic model analysis revealedthat corolla lobe length,corolla lobe width,length-width ratio of corolla lobe,leaf length,leaf width,lengthwidth ratio of leaf,shoot length,cold resistance were controlled by minor-polygene respectively;corolladiameter and crown width were controlled by a pair of additive-dominant major genes respectively;flowerdensity was controlled by two pairs of additive-dominant major genes;plant height was controlled by two pairs ofequally additive-dominant major genes.The heritability of major-gene for corolla diameter,crown width,flowerdensity and plant height were 76.05%,60.3%,72.22%and 64.75%,respectively.This research results wouldprovide a basis for target breeding of new varieties of Forsythia with excellent comprehensive traits.