Improvement of resi̇stant lines against viral (tomato yellow leaf curl virus, tomato spotted wilt virus) and fungal (fusarium crown root and rot) diseases and nematode (meloidogyne incognita) with molecular marker assi̇sted selection

Tomato (Solanum lycopersicum L.) is the most produced and exported vegetable in Turkey. Tomato Yellow Leaf Curl Virus (TYLCV), Tomato Spotted Wilt Virus (TSWV), Fusarium oxysporum f.sp. radicis lycopersici (FORL) and nematode (Meloidogyne incognita) cause important economic losses. The most efficient and environmentally friendly method against diseases and pests is the use of resistant varieties. In the thesis, it was aimed at improving multiple resistant genotypes against diseases and nematode in different types (cherry, coktail, single harvested, beef) with marker assisted selection (MAS). A commercial hybrid carrying Ty-1, Ty-3a, Sw-5, Frl and Mi genes as heterozygous was crossed to four susceptible inbred lines from Bati Akdeniz Agricultural and Research Institute (BATEM). MAS was carried out for five resistantce genes in F1 and F2 generations and biological test were done for TYLCV, TSWV, FORL in F3 generation. MAS for Ty-3a (Ty-1) and Sw-5 genes were compatible with biological tests while the molecular and biological tests for Frl were found to be different in some genotypes. As a result, a total of 95 genotypes resistant to the aforementioned diseases and nematode were improved in different types (cherry, coktail, single harvested, beef) in F3 generation. Homozygous multiple-resistant genotypes were 19 for Ty-3a (Ty-1) and Sw-5 genes, 26 for Mi and Frl genes, 12 for Ty-3a (Ty-1) and Frl genes, 15 for Sw-5 and Frl genes, 7 for Sw-5 and Mi genes, 7 for Ty-3a (Ty-1), Sw-5 and Frl genes, 3 for Sw-5, Mi and Frl genes. Multiple-resistant genotypes were added to the institute breeding material to use in the breeding programs.