First Report of Papaya ringspot virus Infecting Bitter Gourd in China

Abstract

HomePlant DiseaseVol. 100, No. 11First Report of Papaya ringspot virus Infecting Bitter Gourd in China PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Papaya ringspot virus Infecting Bitter Gourd in ChinaL. Zhu, T. Yang, L. J. Chen, H. H. Lin, and D. H. XiL. ZhuSearch for more papers by this author, T. YangSearch for more papers by this author, L. J. ChenSearch for more papers by this author, H. H. LinSearch for more papers by this author, and D. H. XiSearch for more papers by this authorAffiliationsAuthors and Affiliations L. Zhu T. Yang L. J. Chen H. H. Lin D. H. Xi , Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, Sichuan University, Chengdu 610064, China. Published Online:25 Aug 2016https://doi.org/10.1094/PDIS-01-16-0086-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Papaya ring spot virus (PRSV), a species of the genus Potyvirus in the family Potyviridae, is an important pathogen of papaya (Carica papaya L.) and cucurbits in tropical and subtropical regions worldwide (Bateson et al. 2002). The virus is a major limiting factor in papaya production in South China and has been described in pumpkin, luffa, watermelon, winter melon, zucchini, muskmelon, and Siraitia grosvenorii (Zhang et al. 2014; Zhu et al. 2014). During a survey conducted in the summer of 2014, bitter gourd plants showing vein clearing, leaf roll, and stunting symptoms were observed in selected vegetable greenhouses in Sichuan Province of Southwest China. The disease incidence was more than 35% in most fields (>85%), and green peach aphids were observed on some plants. Leaf samples (50) were randomly collected from 15 greenhouses in the main production areas in Chengdu, Shuangliu, and Pengzhou, and tested by Western blotting with commercial antisera (Agdia, Elkhart, IN) against TMV, Chilli veinal mottle virus (CHiVMV), and PRSV. PRSV was detected in five of the samples tested. To confirm the presence of PRSV, total RNA was extracted from the five samples and tested by RT-PCR using a pair of potyvirus group primers (5′-GTITGYGTIGAYGAYTTYAAYAA-3′ and 5′-TCIACIACIGTIGAIGGYTGNCC-3′) (Zheng et al. 2010) and a pair of PRSV-specific primers PRSV-F (5′-TAACACACTGATGGTTTTAATC-3′) and PRSV-R (5′-ATTGCGCATACCCAGGAGAGAG-3′). Expected fragments of a 350-bp region of the nuclear inclusion (NIb) and the complete coat protein (CP) (951 bp) were both obtained. The amplicons were subsequently purified, cloned into the pMD19-T vector (TaKaRa), and sequenced. Sequences of either NIb or CP from five samples, designated as PRSV-SC-J, were identical. Nucleotide BLAST analysis of the NIb (GenBank Accession KT818626), and CP (KU365987) showed that this isolate shares the highest identity (NIb: 92%, CP: 99%) with four isolates from Taiwan (JX448370.1, JX448369.1, JX448373.1, and JX448372.1). The isolate clustered with the PRSV type P isolates in the P clade in phylogenetic analyses of the CP nucleotide sequences of isolates available in GenBank. Recently, an isolate of a CMV-II (Cucumber mosaic virus subgroup II), derived from PRSV-infected bitter gourd leaves, was detected and presumably is involved in facilitative interactions. To our knowledge, this is the first report of PRSV infecting bitter gourd in China. Due to the severity of the bitter gourd disease and its continued increased planting in the areas, better management of seed, vector, and greenhouse sanitation is necessary to control the disease.