辣椒炭疽病基因紧密连锁的KASPar标记的开发

【目的】研究辣椒炭疽病抗性基因的遗传规律。在5号连锁群中,定位辣椒炭疽病抗性主效基因AnR_GO5,并开发分子标记。【方法】以高抗炭疽病品种PBC932(Capsicum chinense )为父本,以高感炭疽病的中早熟材料77013(Capsicum annuum)为母本杂交产生BC₄S₁、BC₄S₂群体,用于辣椒绿熟期抗炭疽病基因定位。选用尖孢炭疽菌为试验用菌,采用显微注射法对绿熟果接病,根据病斑直径进行表型分析。根据抗、感亲本重测序结果,开发与绿熟期抗炭疽病连锁的Kaspar标记。【结果】辣椒果实表面病斑直径呈连续分布,符合数量性状的遗传特点。通过连锁分析,将炭疽病抗性基因AnR_GO5定位在5号连锁群的标记P5L-866与标记P5L-259之间,遗传距离2.9 cM。开发的标记P5L-117 与基因紧密连锁,标记准确率93.5%。【结论】在辣椒的BC₃S₁群体中,将果实绿熟期抗性基因定位于5号染色体的标记区间内。辣椒炭疽病抗性遗传为显性遗传,是由两对主效基因控制的。

Development of KASPar Marker Closely Linked to the Major Gene Resistantto Colletotrichum acutatum in Pepper (Capsicum annuum L.)

【Objective】 To study the inheritance of pepper anthracnose resistance gene, Kaspar marker linked with the anthracnose resistance major gene AnR_GO5 was identified and developed.【Method】Pepper inbred line PBC932 (Capsicum chinense), resistant to anthracnose (Colletotrichum acutatum) was used as the male parent, and the BC₄S₁ and BC₄S₂ populations were obtained by hybridization of the pepper inbred line 77013 (Capsicum annuum) , which was sensitive to anthracnose. The study used Colletotrichum acutatum as the test bacteria, and the green ripe fruit was inoculated by microinjection method, and the phenotypic analysis was carried out according to the diameter of the lesion. Based on the results of re-sequencing of anti- and susceptible parents, Kaspar markers linked to anthracnose in green ripening stage were developed to construct a genetic linkage map.【Result】The diameter of lesions on the surface of pepper fruit was continuous and accorded with the genetic characteristics of quantitative traits. The anthracnose resistance gene AnR_GO5 was mapped to the marker P5L-866 of the 5th linkage group and the marker P5L-259 by linkage analysis, and the genetic distance was 2.9 cM. The marker P5L-117 developed was closely linked to the gene and the labeling accuracy was 93.5%.【Conclusion】 In the BC₃S₁ population of pepper, the fruit green ripening resistance gene was located in the marker interval of chromosome 5. Pepper anthracnose resistance is dominantly hereditary and is controlled by two pairs of major genes.