Induction and Study of Tomato and Pepper Mutants with High Nutritive Quality

The aim of this project was to increase the levels of health-related compounds such as carotenoids in tomato and pepper, through induced mutagenesis integrating them with other economically important characters, and, to study the genomic changes in the mutants, for crop quality improvement. New genetic resources of tomato were developed by using mutant genes controlling high level of carotenes. The genetic potential to synthesize high lycopene and β carotene was evaluated in tomato lines carrying the mutant genes hp and ogc, as well as in progeny of Solanum lycopersicum with the wild tomato background. Molecular characterization using tomato lines originating from interspecific hybridizations between S. lycopesicum and either, S. pimpinellifolium or S. chilense showed that AFLP markers are useful for early identification of F1 hybrids. A relatively large scale of variation throughout the harvest dates was observed in lycopene content of the lines and hybrids studied but the genotypes investigated ranked almost in the same way despite of the variability in the pigment content. Several pepper mutants with increased β carotene levels in fruit, male sterility, lack of anthocyanins, determinate habit, altered fruit shape and changes in fruit position were developed from induced mutagenesis using physical and chemical mutagen. Using mutants with increased β carotene levels as parents F1 hybrids with a twofold increase in their β carotene content were selected. Molecular studies allowed us to establish a marker for orange fruit colour useful for MAS. (author)