Genetic bases of tomatо marker-assisted selection in Belarus

To develop tomato hybrids and varieties with a high fruit quality, we gradually solved the following tasks: development of DNA-marking methods for long shelf life genes; the genes modifying the biosynthesis of carotenoids and their composition; testing of the elaborated methods on the developed breeding material; the selection of samples with different allelic composition of fruit quality genes; the development of F₁ hybrids using the method of successive crosses and their study; the selection of tomato forms by DNA-typing methods with target genes in F₂ populations to develop valuable breeding samples; the study of carotenoids’ accumulation peculiarities and their inheritance.

We used DNA-identification methods for fruit quality genes: nor, rin, nor^A (long shelf life), B, og^c, hp2^dg, gf-3 (carotenoid content). The tomato hybrids, combining two pigment content genes and one long shelf life gene and the model forms with different combinations of fruit quality genes (B/rin/gf-3, B/rin/hp2^dg; B /nor/gf-3, B /nor/hp2^dg; оg^c /rin/gf-3, оg^c /rin/hp2^dg; оg^c /nor/gf-3, оg^c /nor/hp2^dg) in a homozygous state were developed.

Use of the developed accessions with carotenoid content genes (og^c/hp2^dg, B/hp2^dg) as maternal forms and the accessions with complex fruit quality genes (og^c/hp2^dg/nor, og^c/hp2^dg/rin, B/hp2^dg/nor, B/hp2^dg/rin, og^c/gf-3/nor, og^c/gf-3/rin, B/gf-3/rin, B/gf-3/nor) as paternal forms for hybridization contributes to high accumulation of carotenoids and a lond period of fruit storability.