Simple and Efficient Method to Identify Genotypes with Stable Resistance to Diseases over Diverse Environments by Assessing GE Interaction

Stable, disease-resistant genotypes in crop plants are commonly identified using methods such as regression analysis, AMMI, and GGE biplot. However, these approaches are complex and mainly based on the dynamic concept of stability, making them less suitable for identifying stable resistance across diverse environments. Therefore, the objective of the present study was to develop a simple, efficient, and effective method based on the static concept of stability to evaluate genotype × environment (GE) interaction, using Mungbean Yellow Mosaic Virus (MYMV) disease as a model. A total of 60 mungbean genotypes were screened across six diverse environments. Disease severity index (DSI) was calculated, and genotypes were classified into six categories: highly resistant, resistant, moderately resistant, moderately susceptible, susceptible, and highly susceptible. Based on this classification, ranks from 1 to 6 were assigned respectively, and GE interaction was analyzed using a newly introduced ranking method aligned with the static stability concept. The genotype VC 6371-94 was identified as the most stable and highly resistant across environments. In addition, VC 6369 (53-97), VC 6370 (30-65), VC 6372 (45-8-1), VC 6370-92, and VC 6486 (10-51) exhibited stable resistance to MYMV. Among the six environments tested, only three were found to be most suitable for effective screening of genotypes.