ABSTRACT
The immense challenge of food security faced worldwide has directed researchers and scientists towards genetic engineering. Microbial gene engineering, involves modifi cation of qualitative and quantitative traits in an organism by transferring desired genes from one species to another. This stratagem is referred to as the transgenic advance. In contrast to conventional breeding, the transgenic approach allows the incorporation of only the specifi c cloned genes into an organism and restricts the transfer of undesirable genes from the donor organism. Through microbial engineering, pyramiding of genes with similar effects can also be achieved. Rapid advances in recombinant-DNA technology and development of precise and profi cient gene-transfer protocols have resulted in effi cient transformation and generation of transgenic lines in a number of crop species (Gosal et al. 2009). Recent studies reported several miRNAs associated with abiotic stress responses. Recognizing abiotic stress-associated microRNAs (miRNAs) and understanding their function will help develop new approaches for improvement of plant stress tolerance (Barrera-Figueroa et al. 2012, Saini et al. 2012). It is well known that miRNAs are also important in regulating
plant-microbe interaction during nitrogen fi xation by Rhizobium and tumor formation by Agrobacterium.
