Development of tomato cultivars and hybrids with complex resistance to low temperatures and diseases by using gamete breeding and molecular analysis
The article presents the experimental results of estimation efficiency of gamete breeding for cold resistance for development of genotypes with complex resistance to diseases through DNA-analysis. The selection conditions of cold-resistant pollen of tomato maintaining viability of microgametophyte at the 30% level were optimized that provides the sufficient selection efficiency. The ratio of allele frequencies of gene resistant to Fusarium oxysporum (I-2) and Cladosporium fulvum (Cf-5) in the F <sub>2</sub> population was revealed to be approximately identical in the samples in the control and experimental variants after carrying out single selection for cold resistance at the gametophyte level. Valuable breeding material combining resistance to tomato leaf spot, fusarial wilt, and cold stress was selected.