Identification of stable sources of resistance to gummy stem blight (GSB) disease in muskmelon (Cucumis melo L.).

Autor: Ranjitha, Goudru Veerabhadrappa, Rao, Annabatula Mohan, Basanagouda, Gonal, Ramesh, Sampangi, Kavya, Madsur Eshwar, Nateshan, Aradhya, Prashantha, Venkatesha
Zdroj: Genetic Resources & Crop Evolution; Aug2024, Vol. 71 Issue 6, p2497-2507, 11p
Abstrakt: Gummy stem blight disease (GSB) caused by an ascomycete fungi Didymella bryoniae is one of the most destructive biotic production constraints in muskmelon. Development of resistant cultivars is considered as the most economical and eco-friendly option to manage GSB. In this regard, availability of stable sources of resistance is a pre-requisite. A set of 238 muskmelon genotypes were evaluated for responses to GSB under two different natural infection condition viz., under open field during Kharif 2021 and tunnel condition during late Kharif 2021. Further, 44 identified tolerant and resistant genotypes were screened to confirm the consistency of their tolerant/resistant reaction under artificially created GSB sick plot during summer 2022. None of the genotypes were found to be screened were immune or highly resistant to GSB. However, different degrees of resistance response to GSB were observed in terms of typical symptoms. Two genotypes, 21KGSB-258 and 21KGSB-218 consistently expressed resistant response to GSB under both natural infection and sick plot condition with average disease score of 2 and disease index of 40% considering stem-based disease rating scale. Resistant response of these genotypes could be attributed to delayed appearance of initial symptoms, and lower estimates of PDI and area under disease progressive curve (AUDPC). Hence, two genotypes; 21KGSB-258 and 21KGSB-218 identified as stable and potential sources of GSB resistance, could be used as donors to develop GSB resistant muskmelon cultivars/breeding lines. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index