An Update on Biotechnological Approaches for Improving Abiotic Stress Tolerance in Tomato

Tomato ( Solanum lycopersicum L.) is the second most important vegetable crop in the world after potato ( Solanum tuberosum L.), and its productivity is influenced by different abiotic stresses. Though cultivated tomato is moderately tolerant to various abiotic stresses, the crop losses due to unfavorable environmental conditions can be unpredictably severe. So far, several efforts have been made to improve abiotic stress tolerance in cultivated tomato through cultural practices, breeding techniques, and biotechnological approaches. Introgression of abiotic stress tolerance to cultivated tomato from more tolerant wild relatives through classical breeding has been attempted with limited success. However, genetic engineering based on the introgression of genes that are known to be involved in stress response and putative stress tolerance could provide powerful tools for improving abiotic stress tolerance in tomato coupled with the growing knowledge of stress physiology. The present review summarizes the current status and future directions on the use of biotechnological approaches to improve abiotic stress tolerance in tomato.