The present invention relates to an abiotic stress tolerant transgenic plant comprising an Am244 DNA from Avicennia marina. The invention also relates to isolation and characterization of a cDNA corresponding to abiotic stress tolerant gene (Am244 DNA) from Avicennia marina. It further relates to a method for producing abiotic salt-tolerant transgenic plants, plant cells and plant tissues capable of over expressing the Am244 DNA thereby conferring abiotic stress tolerance such as salt, drought and dehydration to otherwise abiotic stress sensitive plant species.