Pepper mild mottle virus isolates from Peru induce severe symptoms in susceptible pepper plants and belong to the P1,2 pathotype

Abstract

Pepper mild mottle virus (PMMoV), a tobamovirus, has been reported worldwide infecting, especially, pepper plants. In this study, seven new PMMoV isolates were identified in symptomatic pepper plants collected in four departments of Peru. The majority of these isolates induced severe symptoms, including mottle, in susceptible pepper plants. Inoculation on pepper plants carrying four known functional L resistance alleles (L1, L2, L3, and L4) revealed that PMMoV isolates from Peru belong to the P1,2 pathotype. Therefore, pepper species or cultivars with L3 and L4 alleles displayed hypersensitive response after mechanical inoculation and were still resistant to PMMoV isolates circulating in Peru. Infection by PMMoV was monitored by serology (DAS-ELISA) and RT-PCR with degenerate primers. Virus genes were used to build a phylogenetic tree that showed diversity accumulation among the PMMoV isolates from Peru.