甜瓜白粉病抗性基因Pm-2F的遗传特性及与其紧密连锁的特异片段

在明确瓜类白粉病生理小种的基础上，以感白粉病新疆哈密瓜〔Cucumis melo L. ssp. melo. convar. ameri (Pang.) Greb.〕来源的自交系K7-2和抗白粉病日本网纹甜瓜〔Cucumis melo L. ssp. melo.convar. cantalupa (Pang.) Greb.〕来源的自交系K7-1为亲本及其F2S6群体为试材，对甜瓜白粉病抗性遗传机制和紧密连锁标记进行深入研究。群体遗传分析表明K7-1对白粉病Podosphaera xanthii （DC.）VP Gelyuta生理小种2F的抗性受一对显性基因Pm-2F控制。同时采用SSR分析技术发现，抗病特异片段CMBR120-172、CMBR8_-98与Pm-2F紧密连锁，连锁距离分别为1 cM和3 cM。抗病特异片段CMBR120_-172在120份甜瓜种质资源材料验证中符合率达87.5%。

Genetic analysis and Specific Fragments Linked to Powdery Mildew Resistant Gene Pm-2F in Melon

Podosphaera xanthii （DC.）VP Gelyuta race 2F caused melon (Cucumis melo L.) powdery mildew was the prevailing race in Beijing. The segregation of resistance had been evaluated in F2S6 population of the cross between the resistant Japanese cantaloupe（Cucumis melo L. ssp. melo.convar. cantalupa (Pang.) Greb.）line K7-1 and the susceptible Xinjiang Hami melon（Cucumis melo L. ssp. melo. convar. ameri (Pang.) Greb.）line K7-2. The resistance to P. xanthii race 2F in K7-1 was controlled by one single dominant Pm-2F gene. SSR technique had been used for the identification of markers linked to powdery mildew resistance. Two specific fragments CMBR120_-172 and CMBR8_-98 were closely linked to Pm-2F gene at a distance of 1 cM and 3 cM, respectively. The efficiency of CMBR120_-172 was about 87.5% in 120 melon germplasms. The markers identified in this experminent were closest to Pm-2F gene to date, and the research, therefore, can be used in melon molecular breeding.