Multi-location evaluation of chili lines carrying different combinations of pvr and Cvr genes for resistance to Chilli veinal mottle virus (ChiVMV)

Start date: 1 July 2020
End date: 30 June 2022

Chilli veinal mottle virus (ChiVMV) (Potyvirus)is probably the second most prevalent chili-infecting virus across South, East, and Southeast Asia. The Capsicum–Potyvirus pathosystem has been well studied and used as a model reference for the study of similar pathosystems in other plant species. Resistance to potyviruses is associated with two major gene groups. First are those with recessive inheritance (pvr1/pvr2, pvr5, pvr6, and pvr8) and associated with a mutation of the host factor eIF4E or eIF(iso)4E. The second group of single-gene potyvirus resistance mechanisms comprises those with dominant inheritance patterns (Pvr4/Pvr7 and Pvr9) and are usually associated with NLR cluster regions. Many factors are involved in resistance to ChiVMV, including the environment, vector-pressure, resistance genes in the host, and pathotype of the virus. There are several pathotypes of ChiVMV in different areas of South and Southeast Asia, and which combination of resistance genes are required for the different pathotypes are not known. More research in this area is required to better understand the pathotype structure of ChiVMV in some of the major chili production regions, which will allow for more efficient resistance gene identification and the rapid development of more durable resistant cultivars. In this project, we will assess the performance of advanced pepper breeding lines carrying different combinations of Pvr and Cvr genes in different locations in Asia where different pathotypes of pepper-infecting ChiVMV are predominant.