Archivio Journal of Plant Pathology

Abstract:

Passion fruit (Passilora edulis, family Passifloarceae) is widely cultivated in Ecuador. In September 2015, mottling and downward curling of the leaves were observed in Quevedo (Los Ríos, Ecuador). Based on the type of symptoms, infection by a potyvirus was suspected. Six symptomatic and symptomless passion fruit samples were screened by DAS-ELISA using specific antibodies (Agdia, USA) to soybean mosaic virus (SMV), a member of the genus Potyvirus, family Potyviridae. All symptomatic samples were ELISA-positive. Total RNA was isolated from a single plant with Triazol (Sigma, USA) and used in RT-PCR to amplify a DNA fragment of ca. 350 bp with universal primers designed in the potyviral NIb domain (Zheng et al., 2008). The amplicon was sequenced and the 322 bp sequence (GenBank accession No. MF370353) was analysed by BLAST and compared with the corresponding sequence of SMV isolates from different countries. The partial NIb gene sequence of isolate SMV-Ecuador showed a 98.1% and 95% maximum identity at the nucleotide and amino acid levels with a SMV isolate from China (KP710874). A phylogenetic tree constructed with MEGA version 4.1 showed that the SMV isolate from Ecuador was closely related to and clustered with the Chinese isolate KP710874, whereas isolates from Canada (HQ166265), South Korea (FJ807700 and FJ640955), China (KX834323) and Iran (KF297335) formed a separate cluster. To the best of our knowledge, this is the first report of SMV on passion fruit in Ecuador.