Caracterização molecular de isolados do Cowpea aphid borne mosaic virus que infectam maracujazeiro (Passiflora spp.) e feijão-caupi (Vigna unguiculata)

Abstract

The occurrence of pests and diseases is presented as one of the main problems the diverse cultures of great agronomic importance. In passion, the fruit woodiness virus and cowpea, cowpea mosaic, viruses are the most important in the world, causing great financial losses. Are caused by Cowpea aphid-borne mosaic virus (CABMV). In passionfruit etiologic agent was named Passionfruit woodiness virus (PWV), genus Potyvirus, and later it was discovered that two more species of the same genus were causing the same disease, the Cowpea aphid-borne mosaic virus (CABMV) and East Asian Passiflora virus (EAPV). In Brazil, recent studies have indicated the CABMV be prevalent as the virus that causes this disease. Given this scenario, the present work was to study the genetic variability of different isolates of CABMV that infect cultures of cowpea and passion fruit in different producing regions of Brazil. Total RNA was extracted using the TRIZOL (Invitrogen) and used in the synthesis of viral cDNA through RT-PCR reactions that were conducted using commercial kits, for different combinations of oligonucleotides. The products of amplification were cloned and sent to sequencing. Were sequenced and characterized seven isolates, five cowpea and from the two passion fruit, and these corresponded to a sequence of 838 nucleotides encoding part of the protein Insertion Cylindrical (CI) and partial sequence of the protein gene 6K2. The nucleotide and amino acid sequences revealed high identity, ranging from 91 to 99% and 84-99% respectively, showing a low genetic variability among isolates of this study.