Role of microRNAs in rice plant under salt stress

Soil salinity is one of the most devastating factors threatening cultivable land. While low to moderate salt stress affects the plant growth rate and yields, the high-salt stress conditions are detrimental for plant growth. The problem of salinity is often compounded by mineral deficiencies and toxicities. Rice is essentially rated as salt-sensitive crop and its salt susceptibility is dependent on the growth stage. The genetic processes that are involved in coordinating the responses to salinity in rice are not very clearly understood, but can be somewhat explained by mechanisms that regulate ion homeostasis, osmolyte production, scavenging of toxic radicals, water conduction and root-shoot response coordination. This is achieved by modifying the gene expression. The microRNAs (miRs) represent an important class of endogenous small RNAs that have the potential to regulate gene expression at post-transcriptional levels. This review discusses the impact of salinity on rice crop and the current knowledge in the area of miRs with their role in the adaptive response to salt and other abiotic stresses, with a focus on rice.