Screening of Capsicum germplasm and inheritance of resistance to chilli leaf curl virus

In India, chilli leaf curl disease (ChiLCD) is emerging as the most destructive threat for chilli production, with its drastic effect on fruit yield and quality. In the present study, we report the molecular characterization of a virulent virus isolate associated with ChiLCD prevalent in Raichur, Karnataka State, India. The complete genome sequencing of the virus isolate exhibited 99.5% sequence identity to ChiLCV-IN [IN:Ahm:09] DNA-A and 98% sequence identity to Tomato leaf curl Bangladesh beta satellite infecting chilli. To identify a durable resistant source, we evaluated 238 chilli genotypes for resistance to the chilli leaf curl virus ChiLCV-Raichur (ChiLCV-Rai) isolate through mass and individual cage inoculation methods using virulent whiteflies. Three Capsicum annuum L. accessions, namely IHR4517, IHR4615, and IHR4630 were found to be highly resistant, which was further confirmed using graft inoculation and PCR. Furthermore, inheritance of resistance was studied, and segregation analysis demonstrated the best fit ratio of 3:1 and 1:1 in F2 and test cross populations, respectively indicating single dominant gene control resistance against the ChiLCV-Rai isolate in two highly resistant lines, namely IHR4517 and IHR4615. These genotypes can be further exploited in the development of ChiLCD-resistant varieties/F1 hybrids. © 2022, Indian Phytopathological Society.