Ty-6, a major begomovirus resistance gene on chromosome 10, is effective against Tomato yellow leaf curl virus and Tomato mottle virus

Abstract

Key message Ty - 6 is a major resistance gene on chromosome 10 of tomato that provides resistance against monopartite and bipartite begomoviruses and complements resistance conferred by the known Ty - 3 and ty - 5 genes. Abstract Resistance to monopartite and bipartite begomoviruses is an important breeding objective for cultivated tomato. Several begomovirus resistance genes have been introgressed from related Solanum species and are available for breeding purposes. In the present study, we mapped an additional locus, Ty - 6 , to chromosome 10 of tomato. Ty - 6 is effective against both monopartite Tomato yellow leaf curl virus (TYLCV) and bipartite Tomato mottle virus (ToMoV). Gene action is incomplete dominance, with an intermediate resistance response when Ty - 6 is heterozygous. Analysis of populations segregating for Ty - 6 along with Ty - 3 or ty - 5 indicates that the highest level of resistance against TYLCV is attained when Ty - 6 is combined with an additional resistance allele. Our results also demonstrate that ty - 5 is ineffective against ToMoV. Although multiple SNPs linked to Ty - 6 were identified and can be used for breeding purposes, none of these were consistently polymorphic between Ty - 6 and ty - 6 breeding lines. Further research is underway to generate resequencing data for several Ty - 6 inbred lines for the discovery of additional sequence polymorphisms that can be used for fine mapping and characterizing the Ty - 6 locus. Electronic supplementary material The online version of this article (10.1007/s00122-019-03298-0) contains supplementary material, which is available to authorized users.

Geminivirus Resistance: A Minireview

“…Ty-4 is a minor locus on tomato chromosome 3 (Ji et al, 2009). Ty-6 lies on chromosome 10, has incomplete dominance, and protects tomatoes against Tomato mottle virus (ToMoV) and TYLCV (Scott et al, 2015;Gill et al, 2019).…”

A Temporal Diversity Analysis of Brazilian Begomoviruses in Tomato Reveals a Decrease in Species Richness between 2003 and 2016

“…Traditionally, the most common preventive measures for begomoviral disease control are the application of insecticides against the vector and the use of resistant cultivars (Lapidot and Friedmann, 2002;Hurtado et al, 2012). To date, genes of the series Ty-1 to Ty-6 (and a few others such as tcm-1 and ty-5) were reported to provide resistance/tolerance to tomato yellow leaf curl virus (TYLCV), the most widespread begomovirus in the world (e.g., Zamir et al, 1994;Giordano et al, 2005;Anbinder et al, 2009;Ji et al, 2009;Hutton et al, 2012;Bai et al, 2018;Gill et al, 2019); some of these genes can provide a moderate level of control against NW begomoviruses (Giordano et al, 2005;Boiteux et al, 2007;Aguilera et al, 2011). For example, an experimental heterozygous hybrid carrying Ty-1 was less infected and displayed milder or no symptom under infection of the Brazilian begomoviruses tomato rugose mosaic virus (ToRMV) and tomato yellow vein streak virus (ToYVSV), and thus classified as tolerant to these viruses (Boiteux et al, 2007).…”

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

“…The recessive TYLCV resistance gene ty-5 from S. peruvianum resides on chromosome 4 and encodes the mRNA surveillance factor Pelota [ 23 ]. Ty-6 , which has been mapped to chromosome 10, is effective in complementing the resistance conferred by Ty-3 and ty-5 [ 24 ]. Additionally, Ty-6 confers resistance to tomato mottle virus (ToMoV), suggesting that Ty-6 controls both mono- and bi-partite begomoviruses in tomatoes [ 24 ].…”

“…Ty-6 , which has been mapped to chromosome 10, is effective in complementing the resistance conferred by Ty-3 and ty-5 [ 24 ]. Additionally, Ty-6 confers resistance to tomato mottle virus (ToMoV), suggesting that Ty-6 controls both mono- and bi-partite begomoviruses in tomatoes [ 24 ].…”