Genetic Analysis and Location of Powdery Mildew Resistance in Melon

Objective: Inheritance of 4 sources of Podosphaera xanthii race 1 resistance and location of powdery mildew resistance in melon was studied to explore powdery mildew resistance resources. Method: Inheritance of several resistant sources was observed by analysis of segregation ratios for resistance / susceptibility in different populations. The location of Px race 1 resistance gene was performed by BSA( Bulked Segregation Analysis) and linked SSR( Simple Sequence Repeat) makers technology. Result: ①The segregation ratios for resistance / susceptibility observed in the different populations and the results of the progeny test indicated that resistance to Px race 1 in PMR45 and Km7 were governed by one dominant gene( χ2= 0. 133,P = 0. 72; χ2= 2. 07,P = 0. 15). The resistance in Edisto47 and HXC did not fit to one dominant gene segregation ratio,but Edisto47 would in accord with the closest genetic model of two independent genes( χ2= 0. 122,P = 0. 73). ②The powdery mildew resistance in PMR45 and Km7 was located on LGⅡ. Two genes were involved in resistance of HXC on LGⅤ and LGⅫ. Conclusion: The genetic analysis and location of four powdery mildew resistance melon cultivars was studied. These results provides a theoretical basis for fine mapping resistance gene and selecting resistance gene in melon breeding.