Development and Application of Gene-Specific Markers for Tomato Yellow Leaf Curl Virus Resistance in Both Field and Artificial Infections

Abstract

Tomato yellow leaf curl virus (TYLCV) is a disease that is damaging to tomato production worldwide. Resistance to TYLCV has been intensively investigated, and single resistance genes such as Ty-1 have been widely deployed in breeding programs. However, resistance-breaking incidences are frequently reported, and achieving durable resistance against TYLCV in the field is important. In this study, gene-specific markers for Ty-2 and ty-5, and closely-linked markers for Ty-4 were developed and applied to distinguish TYLCV resistance in various tomato genotypes. Quantitative infectivity assays using both natural infection in the field and artificial inoculation utilizing infectious TYLCV clones in a growth chamber were optimized and performed to investigate the individual and cumulative levels of resistance. We confirmed that Ty-2 could also be an effective source of resistance for TYLCV control, together with Ty-1. Improvement of resistance as a result of gene-pyramiding was speculated, and breeding lines including both Ty-1 and Ty-2 showed the strongest resistance in both field and artificial infections.

Genotyping-by-sequencing-based QTL mapping reveals novel loci for Pepper yellow leaf curl virus (PepYLCV) resistance in Capsicum annuum

“…Molecular markers linked to potential resistance loci can provide information for early selection and are useful for breeding horticultural crops resistant to viruses [ 47 ]. Several molecular markers associated with virus resistance loci in pepper and tomato has been developed to expedite marker-assisted breeding [ 48 , 49 ]. Introgression of resistance genes into cultivated varieties has been the principal route of breeding cultivars that are resistant to viruses such as Tomato yellow leaf virus (TYLCV), Tomato spotted wilt virus (TSWV), Pepper yellow leaf curl virus (PepYLCV) and Chilli veinal mottle virus (ChiVMV) [ 49 , 50 ].…”

“…Several molecular markers associated with virus resistance loci in pepper and tomato has been developed to expedite marker-assisted breeding [ 48 , 49 ]. Introgression of resistance genes into cultivated varieties has been the principal route of breeding cultivars that are resistant to viruses such as Tomato yellow leaf virus (TYLCV), Tomato spotted wilt virus (TSWV), Pepper yellow leaf curl virus (PepYLCV) and Chilli veinal mottle virus (ChiVMV) [ 49 , 50 ]. The major markers linked to tomato yellow leaf disease (TYLCD) that have been developed to date include a closely linked molecular marker, SCAR1, for screening of the Ty-1 locus [ 51 ], P6-25 and FLUW25 for evaluation of Ty-3 , Ty-3a , and Ty-3b loci [ 37 , 50 , 52 ], and SCAR2 and P1-16 for the detection of Ty-2 [ 39 ].…”

A first glimpse of the molecular mechanism behind Ty-1, an atypical dominant resistance gene

“…By combining different resistance genes, pathogens have to overcome multiple resistance mechanisms to break resistance. In this context, combinations of Ty-2 and Ty-3 (an allele of Ty-1 (Verlaan et al, 2013)), or Ty-1 and Ty-2, are used and shown to result in higher resistance level against several geminiviruses (Lee et al, 2021;Prasanna et al, 2015).…”