Screening of pepper (Capsicum annuum L.) lines for resistance to an isolate of Potato virus Y (PVY) occurring in KwaZulu-Natal (KZN), Republic of South Africa

Abstract

Potato virus Y (PVY) is an economically important virus of field grown solanaceous crops throughout the world. In the province of KwaZulu-Natal (KZN), Republic of South Africa (RSA), the incidence of PVY infection has been reported to significantly reduce the yield and quality of cultivated peppers. This study aims to evaluate commercially grown pepper lines for resistance against PVY. Six commercial F1 pepper lines were challenged with the PVY isolate JVW-186 using mechanical inoculation. Each line was assessed for resistance to PVY by visual screening for disease severity and quantitative triple antibody sandwich enzyme linked immunosorbent assay (TAS-ELISA) for virus load. The pepper lines were further characterized using tetra-primer amplification refractory mutation system polymerase chain reaction (ARMS-PCR) to identify and differentiate homozygous/heterozygous resistance alleles at the pvr2 locus that confers PVY resistance. Our results identified two resistant lines (Double Up and Cecelia) and varying levels of susceptibility in the other lines challenged with PVY. The pvr2+ allele was positively identified in all the susceptible pepper lines which confirmed that the presence of this allele is dominant for PVY susceptibility. The information generated in this study can be used in breeding programs to develop PVY resistant pepper.