Survey of Viruses Present in Radish Fields in 2014

Abstract

A 2014 nationwide survey in radish fields investigated the distribution of common viruses and possible emerging viruses. Radish leaves with virus-like symptoms were collected and 108 samples assayed by RT-PCR using specific primers for Radish mosaic virus (RaMV), Cucumber mosaic virus (CMV), and Turnip mosaic virus (TuMV); 47 samples were TuMV positive, and RaMV and CMV were detected in 3 and 2 samples, respectively. No samples showed double infection of TuMV/RaMV, or RaMV/CMV, but two double infections of TuMV/ CMV were detected. TuMV isolates were sorted by symptom severity, and three isolates (R007-mild; R041 and R065-severe) selected for BLAST and phylogenetic analysis, which indicated that the coat protein (CP) of these isolates (R007, R041, and R065) have approx. 98-99% homology to a previously reported TuMV isolate. RaMV CP showed approx. 99% homology to a previously reported isolate, and the CMV CP is identical to a previously reported Korean isolate (GenBank : GU327368). Three isolates of TuMV showing different pathogenicity (degree of symptom severity) will be valuable to study determinants of pathogenicity.

Comparison of helper component-protease RNA silencing suppression activity, subcellular localization, and aggregation of three Korean isolates of Turnip mosaic virus

“…However, these HC-Pro characters do not correlate with symptom severity (R041, R065 induction of SN in Chinese cabbage and N. benthamiana, R007 mosaic in both; this study, [25]). TuMV symptom determinants appear to be host specific, even within the Brassicaceae.…”

“…TuMV isolates R007, R041, and R065 were selected from R. sativus in Korea [25] based on differential symptoms in R. sativus, B. rapa ssp. pekinensis (Chinese cabbage), and Nicotiana benthamiana.…”

A single amino acid substitution in the conserved CDNQLD motif causes both differences in RNA silencing suppression activity of the turnip mosaic virus HC-Pro protein and variations in symptom severity

“…The mature proteins have several functions which are necessary for protease activity, replication, cell-to-cell movement, aphid transmission, pathogenicity, and suppression of RNA silencing [3]. TuMV can infect various plants in the family Brassicaceae, including Brassica rapa and Raphanus sativus [4], and is commonly found infecting R. sativus in Korea [5]. Radish (R. sativus) is one of the major vegetable and feed crops, widely consumed in China, Japan, Korea, and other Asian countries [6]; the area of radish cultivation in the Asian Far East is much greater than in other countries.…”

“…Radish is one of the main hosts of TuMV in Korea, in which it causes signi cant damage and reduces yields. To identify the pathogenic factors and reduce damage caused by TuMV, previous studies collected TuMV isolates from radish elds across Korea, generated infectious clones, and inoculated them to commonly grown cultivars of radish [5,7].…”

Five Newly Collected Turnip Mosaic Virus (TuMV) Isolates from Jeju Island, Korea are Closely Related to Previously Reported Korean TuMV Isolates but Show Distinctive Symptom Development

“…TuMV was recognized as a major cause of yield loss to radish and Chinese cabbage in the Gangwon area of South Korea (Choi and Choi, 1992; Hahm, 1995 ; Hahm et al, 1998 ). TuMV together with cucumber mosaic virus (CMV) and radish mosaic virus (RaMV) were also reported from a nationwide survey of radish fields conducted in South Korea in 2014 ( Chung et al, 2015 ). Recently, Gong et al (2019) collected new TuMV isolates from South Korea that showed symptoms of varying severity on Chinese cabbage, Nicotiana benthamiana and radish.…”