Resistance to Tomato Yellow Leaf Curl Virus in Tomato Germplasm

Abstract

Tomato yellow leaf curl virus (TYLCV) is a virus species causing epidemics in tomato (Solanum lycopersicum) worldwide. Many efforts have been focused on identification of resistance sources by screening wild tomato species. In many cases, the accession numbers were either not provided in publications or not provided in a consistent manner, which led to redundant screenings. In the current study, we summarized efforts on the screenings of wild tomato species for TYLCV resistance from various publications. In addition, we screened 708 accessions from 13 wild tomato species using different inoculation assays (i.e., whitefly natural infection and Agrobacterium-mediated inoculation) from which 138 accessions exhibited no tomato yellow leaf curl disease (TYLCD) symptoms. These symptomless accessions include 14 accessions from S. arcanum, 43 from S. chilense, 1 from S. chmielewskii, 28 from S. corneliomulleri, 5 from S. habrochaites, 4 from S. huaylasense, 2 from S. neorickii, 1 from S. pennellii, 39 from S. peruvianum, and 1 from S. pimpinellifolium. Most of the screened S. chilense accessions remained symptomless. Many symptomless accessions were also identified in S. arcanum, S. corneliomulleri, and S. peruvianum. A large number of S. pimpinellifolium accessions were screened. However, almost all of the tested accessions showed TYLCD symptoms. Further, we studied allelic variation of the Ty-1/Ty-3 gene in few S. chilense accessions by applying virus-induced gene silencing and allele mining, leading to identification of a number of allele-specific polymorphisms. Taken together, we present a comprehensive overview on TYLCV resistance and susceptibility in wild tomato germplasm, and demonstrate how to study allelic variants of the cloned Ty-genes in TYLCV-resistant accessions.

The NLR Protein Encoded by the Resistance Gene Ty-2 Is Triggered by the Replication-Associated Protein Rep/C1 of Tomato Yellow Leaf Curl Virus

“…The Ty-2 gene in tomato conferring resistance to TYLCV has been extensively exploited in tomato breeding worldwide, in combination with other Ty genes (mostly Ty-1/Ty-3 or ty-5) (Yan et al, 2018). In this study, we have described our successful positional cloning approach to isolating the Ty-2 gene.…”

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

“…Because TYLCV is strictly a whitefly-transmitted virus, there are technical restrictions with respect to manipulating TYLCV infections and maintaining TYLCV-infected tomatoes. TYLCV viruliferous whitefly-mediated inoculation has been widely deployed and facilitates simultaneous monitoring of disease-limiting factors, TYLCV-plant interactions, and insect-plant interactions [ 34 , 35 , 36 , 37 , 38 , 39 , 40 ] However, numerous biotic or abiotic factors can interfere with the inoculation process. In this study, natural infection in the field, and artificial inoculation with infectious TYLCV clones in a growth chamber, were optimized and compared.…”

Geminivirus Resistance: A Minireview

“…Solanum chilense is the most popular wild tomato relative for introgressing Tomato yellow leaf curl virus (TYLCV) resistance, as over 80% of its accessions are resistant (Yan et al, 2018). Many of the Ty family of resistance loci are from this plant.…”