Occurrence and Molecular Characterization of Some Economically Relevant Cucurbit Viruses in Malatya, Turkey

Abstract

Field surveys were conducted from 2016 to 2017 to detect and determine the prevalence of viruses in the major cucurbit growing areas of Malatya. A total of 162, namely 110 melon, 25 pumpkin and 27 watermelon leaf samples were collected from Arapgir, Arguvan and Battalgazi districts from symptomatic and non-symptomatic cucurbit plants. Using molecular methods, the plant samples were tested against four viruses, including Cucumber mosaic cucumovirus (CMV), Zucchini yellow mosaic potyvirus (ZYMV), Watermelon mosaic potyvirus (WMV) and Squash mosaic comovirus (SqMV). Results of RT-PCR tests revealed that none of the samples collected from Arapgir and Arguvan reacted positive against surveyed viruses. However, CMV infection was found in 1 cucumber, ZYMV in 5 pumpkin and WMV in 6 watermelon samples in Battalgazi district. The nucleotide sequences of partial coat protein (CP) genes of ZYMV-Malatya and WMV-Malatya isolates were determined. Nucleotide sequence comparisons revealed 95-100% similarity of ZYMV-Malatya isolate with other isolates of ZYMV reported worldwide with no mutation site on CP gene. However, WMV-Malatya isolate exhibited 94-99% similarity with other WMV sequences reported worldwide consisting a unique mutation site on CP gene sequence. These isolates are recorded to the Gene Bank with the accession numbers MT186266 (Zucchini yellow mosaic virus isolate, Malatya ZYMV1) and MT186267 (Watermelon mosaic virus isolate Malatya WMV1).