Utilization of wild melon (Cucumis melo var. callosus) to develop downy mildew resistant muskmelon inbred line, MM-31
Under-exploited cucurbit, wild melon (Cucumis melo var. callosus) is a reservoir for resistance genes for downy mildew and other economically important diseases of melon. Previously, efforts have been made to introduce resistance genes to commercial cultivars but with limited success due to the associated drag of inferior fruit quality traits such as sour taste and reduced shelf life. In the current study, a wild melon land race, Mehna Chibber which possessed high level of resistance against downy mildew was involved in a backcross breeding programme with a well-adapted cultivar, 'Punjab Sunehri' as recurrent parent. From BC5 generation onward, segregating progenies obtained from inbreeding were simultaneously screened against downy mildew and for superior fruit quality attributes for six years. The resistant lines possessing superior fruit quality traits were selected and selfed. Finally, a downy mildew resistant breeding line MM-31 (MCPS-1-7-5-4-2) was evolved. The inbred line MM-31 showed very low disease severity reaction to downy mildew (1.6%) as compared to 'Punjab Sunehri' (15.7%). Thus, the inbred line MM-31 was observed as a true breeding line with high yielding ability and superior fruit quality along with downy mildew resistance. The total soluble solids in MM-31 varied from 11 to 13% and fruit yield (13.4 t ha‑1) was 11.8% higher than 'Hara Madhu' and comparable with 'Punjab Sunehri'. Thus, MM-31 can be a potential parent for developing improved hybrids in muskmelon due to its having high resistance to downy mildew and good horticultural traits.
Vashisht, V.K., Lal, T., Sharma, S.P. and Thind, T.S. (2019). Utilization of wild melon (Cucumis melo var. callosus) to develop downy mildew resistant muskmelon inbred line, MM-31. Acta Hortic. 1241, 729-734
backcross, fruit quality, introgression, resistance breeding, 'Punjab Sunehri'