Vegetables II

Abstract

Tomato (Lycopersicon esculentum Mill) is an economically important vegetable that is widely used for both basic and applied research. Numerous advantageous features render tomato as a favorable model species for plant research in areas of classical genetics, cytogenetics, molecular genetics, and molecular biology. Its self-pollinating nature, easy crossability to the wild species, simple genome, and vast genetic variation render tomato an ideal species for classic genetic studies. The 12 chromosomes in the tomato genome can be readily identified through analyses of pachytene karyotype, synaptonemal complexes, and chromosome or chromosome arm-specific DNA sequences, making it an excellent species for cytogenetic research. Moreover, its small genome size (w950 Mb), various high-density molecular linkage maps, and numerous genomic databases and DNA libraries-such as expressed sequence tags and bacterial artificial chromosomes-make tomato a model system for molecular genetic and genomic studies. In addition, the ease of cell culture and genetic transformation by Agrobacterium-based vectors render tomato an excellent species for genetic engineering and molecular biology studies. Because of these outstanding features and its economic importance, tomato has been chosen by the recently initiated International Solanaceae Genome Project (SOL) as the Solanaceae model species for genome sequencing. The availability of whole genome sequences in the next decade will likely lead to a better understanding of plant adaptation and diversification. The utilization of potential natural variation discovered from the SOL project will accelerate tomato improvement, and thus improve the health and wellbeing of humans in a more environmentally friendly and sustainable manner.