In vitro selection for drought and salt stress tolerance in rice: an overview

In the past few decades, in vitro selection based on tissue culture techniques has developed as a useful tool for improving biotic as well as abiotic stress tolerance in crops. Rice is a staple crop and is susceptible to drought and salt stress. Tolerance can be acquired in vitro by using selection agents such as polyethylene glycol, mannitol, salicylic acid, sorbitol, sucrose for drought tolerance and sodium chloride (NaCl) for salt stress tolerance. There have been several reports of successful in vitro screening for stress tolerance such as drought and salt in different rice cultivars. In vitro screening helps in earlier determination of stress tolerance/ susceptibility under control condition unlike field screening, however validation needs field screening. This paper reviews the work done on in vitro screening of rice for salt and drought stress tolerance. In Indian scenario, drought and salinity is a challenge for rice crop production and the use of in vitro selection may aid in development of new cultivars of rice under stressed conditions.