The esculent Lycopersicon esculentum, long thought to be poisonous, has become a major U. S. food crop and source of vitamins and minerals, thanks largely to genetic modification and new production technology Rick (1978) Tomato (Lycopersicon esculentum Mill. ) is one of the most important solana ceous vegetable crops grown worldwide under outdoor and indoor conditions. It has become an important commercial crop so far as the area, production, industrial values and its contribution to human nutrition is concerned. During the past few decades tremendous developments have contributed to the...

Wild taxa are invaluable sources of resistance to diseases, insects/ pests, nematodes, temperature extremes, salinity and alkalinity stresses, and also of nutritional quality; adaptation; genetic diversity and new species. Utilization of wild relatives of a crop depends largely upon its crossability relations with cultivated varieties. Sev eral wild species are not crossable with the commercial cultivars due to various isolation barriers. Furthermore, in a few cases, hybridiza tion is possible only in one direction and reciprocal crosses are not successful, thus depriving the utilization of...