High-resolution mapping of zym, a recessive gene for Zucchini yellow mosaic virus resistance in cucumber

Abstract

Using a high-resolution mapping approach, we identified a candidate gene for ZYMV resistance in cucumber. Our findings should assist the development of high-versatility molecular markers for MAS for ZYMV resistance. Zucchini yellow mosaic virus (ZYMV) causes significant disease, which leads to fruit yield loss in cucurbit crops. Since ZYMV resistance is often inherited recessively in cucumber, marker-assisted selection (MAS) is a useful tool for the development of resistant cucumber cultivars. Using 128 families of an F2:3 population derived from a cross between susceptible 'CS-PMR1' and resistant 'A192-18' cucumber inbred lines, we confirmed that ZYMV resistance is conferred by a single recessive locus: zym (A192-18) . We constructed a cucumber genetic linkage map that included 125 simple sequence repeat (SSR) markers segregating into 7 linkage groups (chromosomes). The zym (A192-18) locus was mapped to chromosome 6, at genetic distances of 0.9 and 1.3 cM from two closely linked SSR markers. For high-resolution genetic mapping, we identified new molecular markers cosegregating with the zym (A192-18) locus; using cucumber genomic and molecular marker resources and screening an F2 population of 2,429 plants, we narrowed down the zym (A192-18) locus to a <50-kb genomic region flanked by two SSR markers, which included six candidate genes. Sequence analysis of the candidate genes' coding regions revealed that the vacuolar protein sorting-associated protein 4-like (VPS4-like) gene had two SNPs between the parental lines. Based on SNPs of the VPS-4-like gene, we developed zym (A192-18) -linked DNA markers and found that genotypes associated with these markers were correlated with the ZYMV resistance phenotype in 48 cucumber inbred lines. According to our data, the gene encoding VPS4-like protein is a candidate for the zym (A192-18) locus. These results may be valuable for MAS for ZYMV resistance in cucumber.

Genetic analysis and gene mapping of papaya ring spot virus resistance in cucumber

“…Wai et al (1997) detected linkages between resistance to ZYMV and Watermelon mosaic virus (WMV), between resistance to PRSV-W (prsv-2), ZYMV (zym), and bitterfree cotyledon (bi). The ZYMV resistance gene, zym, has been recently fine mapped, and a candidate gene was proposed (Amano et al 2013). Based on the SSR markers linked with prsv 02245 resistance gene in '02245' from the present study (Fig.…”

cmv1 is a gate for Cucumber mosaic virus transport from bundle sheath cells to phloem in melon

“…They affect the accumulation of the virus mainly at the single cell level, although effects on cell-to-cell movement have also been reported (for a review, see Truniger and Aranda, 2009). Only few recessive resistances are governed by genes encoding other types of proteins and they all restrict virus multiplication, not systemic virus transport (Amano et al, 2013;Ouibrahim et al, 2014;Yang et al, 2014;Yoshii et al, 2009).…”

Different Haplotypes Encode the Same Protein for Independent Sources of Zucchini Yellow Mosaic Virus Resistance in Cucumber

“…DNA was isolated from cucumber accessions ZYMV-resistant TMG-1 (Park et al, 2000;Provvidenti, 1987;Provvidenti et al, 1984a) and Dina-1 (Abul Hayja and Al-Shahwan, 1991), ZYMV-susceptible 'Straight 8' (St 8), and 49 F 6 recombinant inbred lines (RILs) from a cross of TMG-1 and St 8 (Park et al, 2000) from bulked leaf tissue from at least five plants using the DNeasy Ò Plant Maxi Kit protocol (Qiagen, Valencia, CA). We genotyped the candidate gene for zym in St 8, TMG-1, and the 49 RILs using the cleaved amplified polymorphic (dCAPS-G99A) marker developed by Amano et al (2013). Digested amplicons were visualized after running through 8% polyacrylamide gels and silver stained.…”

“…The potyviruses (Potyviridae) are especially destructive for cucumber (Cucumis sativus L.) and production is often negatively affected by Watermelon mosaic virus (WMV), the watermelon strain of the Papaya ringspot virus (PRSV-W), and ZYMV. ZYMV is one of the most devastating and economically important virus diseases of cucumber worldwide (Desbiez and Lecoq, 1997;Lecoq et al, 1983;Provvidenti et al, 1984a), and several strains have been differentiated by serological and molecular approaches (Amano et al, 2013;Mahgoub et al, 1997;Nov akov a et al, 2014;Provvidenti et al, 1984aProvvidenti et al, , 1984b. Resistance to ZYMV has been reported in cucumber.…”

“…Svoboda et al (2013) reported A192-18, G22, and TMG-1 as immune to ZYMV-H because no virus was detected by using enzyme-linked immunosorbent assay and electron microscopy. Amano et al (2013) proposed a VPS4-like gene as the candidate for zym A192-18 , which may affect virus movement throughout the plant and it is the first example of association between a vacuolar sorting protein and a recessively inherited virus resistance in plants. In this research, we analyzed sequences of the VPS4like gene from three sources of ZYMV resistance and two susceptible cucumbers, and revealed that in spite of different haplotypes, all three sources of ZYMV resistance encode the same protein sequence.…”