Resistance Against Melon Chlorotic Mosaic Virus and Tomato Leaf Curl New Delhi Virus in Melon

Abstract

Thirty-one melon accessions were screened for resistance to the begomoviruses Melon chlorotic mosaic virus (MeCMV) and Tomato leaf curl New Delhi virus (ToLCNDV). Five accessions presented nearly complete resistance to both viruses. Accession IC-274014, showing the highest level of resistance to both viruses, was crossed with the susceptible cultivar Védrantais. The F1, F2, F3/F4, and both backcross progenies were mechanically inoculated with MeCMV. Plants without symptoms or virus detection by enzyme-linked immunosorbent assay and/or PCR were considered as resistant. The segregations were compatible with two recessive and one dominant independent genes simultaneously required for resistance. Inheritance of resistance to ToLCNDV in the F2 was best explained by one recessive gene and two independent dominant genes simultaneously required. Some F3 and F4 families selected for resistance to MeCMV also were resistant to ToLCNDV, suggesting that common or tightly linked genes were involved in resistance to both viruses. We propose the names begomovirus resistance-1 and Begomovirus resistance-2 for these genes (symbols bgm-1 and Bgm-2). Resistance to MeCMV in IC-274014 was controlled by bgm-1, Bgm-2, and the recessive gene melon chlorotic mosaic virus resistance (mecmv); resistance to ToLCNDV was controlled by bgm-1, Bgm-2, and the dominant gene Tomato leaf curl New Delhi virus resistance (Tolcndv).

First report of Tomato leaf curl New Delhi virus infecting courgette in France

“…The symptoms were similar to those of Tomato leaf curl New Delhi virus (ToLCNDV), an emerging bipartite begomovirus affecting cucurbits in the Mediterranean Basin (Fortes et al ., 2016). After DNA extraction, PCR was performed on a symptomatic sample (CD20001) with specific primers TLCNDV‐CP‐5 and TLCNDV‐CP‐3, and ToLCNDV‐B‐900‐5 and ToLCNDV‐B‐1940‐3 (Romay et al ., 2019) targeting ToLCNDV DNA‐A and DNA‐B respectively. The amplified fragments (760 bp and 1072 bp) displayed 99.1% and 99.6% identity respectively to ToLCNDV isolate MU.12.ZU/1/2 (MH577761) from Spain.…”

A Major QTL Located in Chromosome 8 of Cucurbita moschata Is Responsible for Resistance to Tomato Leaf Curl New Delhi Virus

“…In fact, in melon, besides the major QTL of chromosome 11, two additional minor regions in chromosomes 12 and 2 modifying the resistant response were identified (Sáez et al, 2017). In a recent publication (Romay et al, 2019), one recessive (bgm-1) and two dominant (Bgm-2 and Tolcndv) genes were also found controlling resistance to ToLCNDV in the same Indian accession WM-7. A similar oligogenic control, three dominant genes, has been reported in S. habrochaites S. Knapp & D. M. Spooner, a wild species related to tomato, after ToLCNDV agroinoculation (Rai et al, 2013).…”

Resistant Sources and Genetic Control of Resistance to ToLCNDV in Cucumber

“…In melon, a major locus in chromosome 11 and two additional regions in chromosomes 2 and 12 controlling the resistance of the wild agrestis accession WM-7 were found [ 24 ]. In a recent publication, Romay et al [ 55 ] identified in the same Indian accession WM-7 one recessive ( bgm-1 ) and two dominant ( Bgm-2 and Tolcndv ) genes controlling the resistance to ToLCNDV. In Cucurbita moschata , a major recessive gene located in chromosome 8 was found controlling the resistance in an Indian accession.…”