FIRST REPORT OF CUCURBIT APHID-BORNE YELLOWS VIRUS AFFECTING SUMMER SQUASH AND MELON IN MONTENEGRO

Abstract

The phytosanitary status of cucurbit crops in the central and coastal regions of Montenegro was evaluated with a survey in 2015. Leaf samples of summer squash, zucchini squash (Cucurbita pepo L.) and melon (Cucumis melo L.) showing mosaic, interveinal mottling or yellowing, bright yellowing, blisters and distortions were collected from 101 plants. All samples were screened by DAS-ELISA (Bioreba, Switzerland) for Cucumber mosaic virus (CMV), Watermelon mosaic virus (WMV), Moroccan watermelon mosaic virus (MWMV), Zucchini yellow mosaic virus (ZYMV), Zucchini yellow fleck virus (ZYFV) and Papaya ringspot virus (PRSV). Serological analysis showed that 91.1% of the samples were infected with at least one of three viruses, the most prevalent of which was CMV (62.4%), followed by WMV (50.5%) and ZYMV (12.9%). Samples from 20 plants showing symptoms resembling those caused by poleroviruses were analyzed by RT-PCR using the coat protein (CP) gene-specific primers CE9/CE10 of Cucurbit aphid-borne yellows virus (CABYV) (Juarez et al., 2004) An amplicon of the expected size (600 bp) was generated from six samples of summer squash and one of zucchini squash. Single infections by CABYV were found in two of seven positive samples, while other five were co-infected with CMV, WMV and/or ZYMV. Nucleotide sequences of the complete CP gene from four Montenegrin isolates (accession Nos. KX398662-KX398665) were identical to one another, sharing the highest nucleotide identity (99.1%) with an isolate from France (X76931). A previous survey in the former Yugoslavia did not reveal the presence of CABYV (Dukic et al., 2002). Afterwards, the virus has been reported in several neighboring countries (Tomassoli and Meneghini, 2007; Vucurovic et al., 2011), but to our knowledge, this is the first report of CABYV infecting C. pepo in Montenegro.