Marker assisted selection of Ty-2 and Ty-3 carrying tomato lines and their implications in breeding tomato leaf curl disease resistant hybrids

Abstract

Tomato leaf curl virus disease caused by whitefly-transmitted begomoviruses is a serious tomato production constraint in tropical and subtropical regions of the world. Use of genetic resistance for diseases caused by begomoviruses is an important component of sustainable disease management approaches. To date, six introgressions (Ty genes) derived from different tomato wild species that confer resistance to tomato leaf curl disease have been identified. Among these, dominant Ty-2 and partially dominant Ty-3 are important for the development of resistant hybrids because of their gene action. In the present study we report marker assisted selection of tomato lines carrying Ty-2 and Ty-3 genes and the effect of combining these in tomato hybrids using agroinoculation. The response of lines and hybrids with the Ty-2 gene indicated ineffectiveness of Ty-2 to infection by a bipartite tomato leaf curl virus. The Ty-3 gene showed dosage effect with partial resistance in heterozygous state. However, the level of resistance in hybrids with the combination of Ty-2 and Ty-3 genes was higher and similar to homozygous Ty-3 plants.The Ty-2 gene in either homozygous or heterozygous state enhanced the level of resistance of plants with heterozygous Ty-3. Thus, tomato hybrid breeding programs can be benefited by using tomato lines carrying Ty-2 and Ty-3 resistance genes. The combined results of evaluation of horticultural performance, field resistance and agroinoculation tests demonstrated that the set of tomato lines developed in this study could be useful resources for achieving higher level of resistance in tomato hybrids.

Tomato Leaf Curl New Delhi Virus: An Emerging Virus Complex Threatening Vegetable and Fiber Crops

“…These findings suggest that instead of classical R gene-mediated hyper-sensitive response (HR), these Ty loci seem to adopt a different mechanism of strengthen host defense response. Prasanna et al [ 34 , 94 ] have shown that the combination of Ty-2 and Ty-3 genes enhanced the resistance level of tomato lines against ToLCNDV and betasatellite.…”

Back into the wild—Apply untapped genetic diversity of wild relatives for crop improvement

“…The tomato wild relatives that have been used include Solanum chilense (Zamir et al., ), Solanum habrochaites (Prasanna, Kashyap, et al. ; Prasanna, Sinha, et al. ), Solanum peruvianum (Lanfermeijer, Warmink, & Hille, ; Seah, Yaghoobi, Rossi, Gleason, & Williamson, ) , Solanum pennellii (Parniske et al., ), and Solanum pimpinellifolium (Chunwongse, Chunwongse, Black, & Hanson, ).…”

“…In a recent study, tomato cultivars carrying a single wild‐derived TYLCY‐resistant gene, Ty‐2 or Ty‐3, or their pyramided lines, had greater yields in the presence of the pathogen TYLCY than cultivars lacking these genes (Prasanna, Kashyap, et al. ). The yield increases in these cases mostly are attributable to the enhanced resistance/tolerance to biotic or abiotic stresses generated by introducing the resistant/tolerant alleles from their wild relatives.…”

Vegetable Improvement in India; Recent Past, Present and Future: A Review

“…For the first time in Indian long day onion population, DNA marker for male sterility and hybrid development has developed and identified with the help of which we can exploit the identified marker in future for hybrid development as well as transfer of male sterility to other onion lines or genotypes through marker assisted selections (Saini et al, 2015). Marker assisted selection has been employed in tomato for the introgression of Ty2 and Ty3 genes to develop tomato leaf curl resistant hybrid (Prasanna et al, 2015).…”