First report of Pepper vein yellows virus in field-grown pepper in Ivory Coast

Abstract

In 2014 and 2015, leaf samples from field-grown pepper (Capsicum annuum L. and C. chinense Jacq.) plants showing different kinds of viral symptoms were collected in Ivory Coast. Samples were dehydrated onto calcium chloride before RNA extraction (Tri Reagent, Molecular Research Center, USA). Two-step RT-PCRs were performed as de- scribed by Knierim et al. (2010) with polyvalent primers for poleroviruses targeting part of the RNA-dependent RNA polymerase, coat protein and movement protein genes. Am- plicons of the expected size (ca. 1,100 bp) were obtained from four of 20 analyzed C. chinense samples originating from Arrah and Bongouanou (South-East Ivory Coast). The source plants exhibited leaf yellowing and rolling as well as stunting. PCR products were sequenced directly (GenBank accession Nos KT825996 to KT825999). Sequence analysis with the BLASTN software showed 97 to 98% nucleotide identity with Pepper vein yellows virus (PeVYV) isolates from Mali as closest sequences (Knierim et al., 2013). These se- quences were aligned with additional ones available in Gen- Bank using ClustalW, leading to a 964-nucleotide alignment. Phylogenetic trees obtained with MEGA6 were consistent between neighbor-joining, maximum-likelihood and maxi- mum parsimony methods and showed that the sequences from Ivory Coast isolates clustered with two pepper isolates collected in 2009 in Mali (accession Nos JX427535 and JX427536) in a separate clade (92% bootstrap value). Pepper veinal mottle virus (genus Potyvirus) and Cucumber mosaic virus (genus Cucumovirus) are the two most widespread pep- per viruses in Ivory Coast but PeVYV is an additional threat to pepper production in this area.