Abstract:

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.

Key words: melon, Cucumis melo L., powdery mildew, resistant gene, specific fragments