萝卜不同抗源对黑腐病抗性的遗传分析

Genetic Analysis on the Resistance of Different Radish Germplasm to Black Rot

不同抗病基因的挖掘是作物持久抗性遗传改良的基础。本研究利用2份抗黑腐病(Xanthamonas campestris pv.campestris)萝卜(Raphanus sativus L.)材料(KB10Q-22、KB10Q-24)和1份感病材料(KB10Q-33)构建了2个F2群体,采用苗期剪叶+喷雾法接种黑腐病菌Xcc8004进行抗病性鉴定。应用P1、P2、F1、F24个世代的数量性状主基因+多基因混合遗传分析方法,研究了萝卜2个不同抗源抗黑腐病的遗传规律,结果表明2份材料的遗传规律不同。以KB10Q-22为母本的F1植株表现为抗病,其遗传模型为E_0模型,即2对加性-显性-上位性主基因+加性-显性-上位性多基因模型;而以KB10Q-24为母本的F1植株表现为感病,其遗传模型为D_0模型,即1对加性-显性主基因+加性-显性-上位性多基因模型。两群体主基因遗传率分别为87.73%和55.64%,抗性遗传以主基因为主。

Abstract：Developing different resistant genes is the basis for the genetic improvement of crops durable resist- ance. Two radish （ Raphanus sativus L. ） inbred lines resistant to black rot （ Xanthamonas campestris pv. campestris ） （KBIOQ-22, KB10Q-24）and one susceptible inbred line （KB10Q-33 ）were used to construct F2 populations. Black rot pathogen Xcc8004 was used to inoculate seedlings by leaf-cutting with spray method to identify the disease-resistance. The inheritance of resistance to black rot was studied with a mixed model of major genes plus poly-genes using Pl, P2, F1 ,and F2populations. The results showed that the inheritance of the resistance of the above two resistant lines was different. The plants of F1 generation from KB10Q-22 expressed resistant. Its genetic model was mixed two major genes with additive-dominance-epistatic effects plus poly genes with additive-dominance-epistatic effects （ E0 model）,while the plants of F1 generation from KB10Q-24 expressed susceptible,and its genetic model was mixed one major gene with additive-dominance effects plus poly genes with additive-dominance-epistatic effects （D_0model）. Major gene heritabili- ties for the two crosses were 87. 73% and 55.64% ,respectively. The heritability was mainly dominated by major genes.