Screening of bitter gourd (Momordica charantia) germplasm for sources of resistance against melon fruit fly (Bactrocera cucurbitae) in Pakistan

Thirteen bitter gourd germplasm per cultivars (Col-II, FSD-long, Col-Nankana Sahib, Col-I, GS-51, Col-III, Col-Multan, Col-Vehari, Chaman, Sunder-F1, Janpuri, F1-484 & F1-485) were screened for sources of resistance against melon fruit fly in Pakistan. Results revealed that the percent fruit-infestation and larval density per fruit varied significantly in all tested bitter gourd genotypes. Based on the considered criteria i.e., percent fruit infestation (less than 20%) and larval density per fruit (3 larvae fruit-1), Col-II and FSD-long were categorized as resistant genotypes. Col-Nankana sahib, Col-I and GS-51 showed greater than 20% but less than 50% fruit infestation and greater than 3 but less than 6 larvae per fruit were categorized as moderately resistant genotypes. Col-III, Col-Multan, Col-Vehari, Chaman, Sunder-F1, Janpuri, F1-484 and F1-485, with less than 50% but less than 80% fruit-infestation and greater than 6 but less than 10 larvae per fruit were categorized as susceptible genotypes. It was concluded that Col-II and FSD-long can be used as a source of resistance for developing bitter gourd genotypes resistant to melon fruit flies.