A Rapid Disease Resistance Breeding in Tomato (Solanum lycopersicum L.)

Abstract

Cultivated tomato (Solanum lycopersicum L.) is an economically important vegetable crop and also a research model plant for many biological and genetic studies. Cultivated tomatoes are susceptible to many diseases which are the serious threats in tomato cultivation and cause of low productivity. Among the biotic stresses, tomato leaf curl disease, Groundnut bud necrosis virus, bacterial wilt, early blight, late blight and root-knot nematodes have become serious threats in tomato production leads to yield reduction in major tomato-growing areas worldwide. Conventional breeding efforts have been made to develop resistant breeding lines or cultivars to combat diseases. In the past few decades, the development of “omics” science especially genomics and bioinformatics provided opportunity to breeders to integrate traditional breeding strategies with omics tools for resistance breeding. With the advent of DNA markers, marker-assisted selection greatly facilitated the introgression of single or multiple resistance genes or QTLs into cultivated tomatoes for disease resistance. Marker-assisted gene pyramiding facilitated increase in level of resistance and durability by combining two or more resistant genes. Marker-assisted selection aided several advantages than conventional breeding such as increased efficiency and reliability of selection of resistance at seedling stage which results in speed in breeding cycle. Several tomato wild species have been exploited for disease resistance breeding by introgressing resistance gene into domesticated tomato. In this chapter, we compiled the currently available molecular markers that confer resistance against major tomato diseases, including late blight, early blight, Tomato yellow leaf curl virus (TYLCV), Tomato spotted wilt virus (TSWV), Tomato mosaic virus (ToMV), verticillium wilt, fusarium wilt, leaf mold, root-knot nematodes, bacterial spot and bacterial speck, and also the use of resistance source(s), availability of resistance gene(s) conventional and marker-assisted breeding approaches for improving disease resistance in tomato.