Abstract: Effects of seed treatments of priming, soaking and hydration-dehydration on emergence and seedling growth of fresh-market and processing tomatoes (Lycopersicon esculentum Mill. cvs H 2274 and Rio Grande) were evaluated under stress conditions of low temperature, drought and salinity. Seed treatment × stress condition interaction was not significant for all of the criteria tested. For both cultivars, while the seed treatments did not result in significant increases on emergence percentage compared with untreated seeds, the treated seeds on the other hand emerged faster and were greater in seedling length, fresh weight, and diameter compared to non-treated seeds. The results indicated that the seed pretreatments tested may be an alternative of choice to improve emergence and seedling growth, and stress factors can be exploited in the manipulation of seedling development.