Exploration of stable host-plant resistant sources to sterility mosaic disease of pigeonpea (Cajanus cajan L. Huth)

Sterility mosaic disease (SMD) presents a major challenge in pigeonpea cultivation throughout the Indian subcontinent. Chemical control methods, such as acaricides, are neither economically viable nor sustainable, making host plant resistance the preferred approach for managing this disease. In this study, we evaluated 45 pigeonpea germplasm accessions and breeding lines for SMD resistance over two consecutive Kharif seasons (2021-22 and 2022-23). Of the 45 genotypes tested, 8 exhibited low disease incidence (0-10%) (LRG-471, ICPL 151, ICPB 2089, ICPB 2047, ICPB 2092, ICPB 2211, ICPL 85063, and ICPL 14003) and were classified as resistant. Additionally, 23 genotypes showed disease incidence between 10.1-20.0% and were categorized as moderately resistant. These resistant genotypes offer promising new sources of SMD resistance and should be considered for inclusion in future pigeonpea breeding programs aimed at improving resistance. This research provides valuable phenotypic insights and identifies stable resistant sources essential for advancing SMD resistance breeding efforts.