西瓜PRSV-W和ZYMV-CH抗性的遗传与连锁分析

Analysis on the inheritance of resistance to PRSV-W and ZYMV-CH and their linkage in watermelon

番木瓜环斑病毒西瓜株系(PRSV-W)和小西葫芦黄化花叶病毒中国株系(ZYMV-CH)是危害我国西瓜的主要病害。以抗病毒病西瓜野生种质P.I.595203与感病普通西瓜自交系98R为亲本,采用单粒遗传方式得到109个F3代株系。分别对亲本、F1及F3代109个株系群体进行了苗期抗PRSV-W和ZYMV-CH接种鉴定,通过F3代群体的抗感分离情况来推测F2代单株的基因型,并分别对PRSV-W与ZYMV-CH抗性遗传及其这2个抗性基因的连锁关系进行分析。研究结果发现P.I.595203对PRSV-W的抗性是由单隐性基因控制,同时可能存在微效修饰基因,将此基因暂定名为prs-W;同时进一步证实了西瓜对ZYMV-CH的抗性由单隐性基因zym-CH控制,zym-CH和prs-W2个抗性基因在遗传上存在一定连锁关系,其遗传距离是27cM。

The Papaya ringspot virus watermelon strain （PRSV-W） and the Zucchini yellow mosaic virus Chinese strain （ZYMV-CH） are two main viruses that cause severe losses in watermelon. The 109 F3 line was derived from the single cross between the resistant germplasm P.I.595203 and the susceptible inbred 98R and their resistances to ZYMV-CH and PRSV- W were identified. The 109 F2 individuals＇ genotypes were assumed by the F3 population resistance segregation result. The inheritance and linkage of resistance to ZYMV-CH and PRSV-W in the watermelon wild accession P.I.595203 were analyzed. We found the resistance to PRSV-W was controlled by a single recessive gene prs-W and confirmed that the resistance to zym-CH was controlled by a single recessive gene zym-CH. The linkage analysis result showed that the resistant genes to prs-W and zym-CH in watermelon were linked unclosely and the linkage distance was 27cM.