Avanços na ciência e tecnologia agrícola

Abstrato

Review on Genetics and Breeding of Tomato (Lycopersicon esculentum Mill)

Damtew Abewoy Fentik

Tomato is considered as a member of the family Solanaceae. The botanical name of tomato is Lycopersicon esculentum Mill and is a diploid plant with 2n=2x=24 chromosomes. Great advances in tomato genetics have been achievable because of the understanding of mating systems and the possibility of controlled hybridization within and among species, the naturally occurring variability in the species, the occurrence of self-pollination that leads to the expression of recessive mutations, the lack of gene duplication, and the possibility to easily identify the 12 chromosomes. New methodological approaches like molecular mapping of important agronomical characters and the development of advanced-backcross and introgression lines have provided powerful tools for the improvement of the tomato crop and to understand the processes of domestication. The general breeding goals of tomato are fruit yield, fruit quality, and resistance to diseases and pests. Tomatoes are presented as a classical example for gene transfer from wild species into cultivated cultivars for improvement the qualitative traits. It was established that until now the achievements in tomato breeding are based on classical breeding-genetic methods and also, an essential change in the accelerated introduction of useful traits in the cultivars is not made. It is believable that conventional breeding wouldn’t allow the increase of productivity in the future. The significant progress in molecular genetics and use of molecular marker techniques are established. Therefore, the combined application of traditional breeding and contemporary plant biotechnology methods including selection based on molecular markers marker-Assisted Selection might be valuable tools for tomato breeding.