Identification of phytohormone changes and its related genes under abiotic stresses in transgenic rice

Abiotic stresses, such as drought and salinity, adversely affect plant growth and productivity. Comparison between non transgenic and transgenic rice harboring CaMsrB2 gene, which induces tolerance to abiotic stress, is important to observe response of gene under abiotic stress. Phytohormone showed a tendency to increase under the drought stress or salinity stress in the transgenic plant. RT-PCR analysis showed that gene expression and phytohormone levels under abiotic stress, to be closely related. The CaMsrB2 gene is related to the expression of JA and ABA hormones. Therefore, the level of expression of these genes and hormones was observed. The transcription levels of LOX2 and OsWRKY45 were substantially higher in the wild type rice in comparison to the transformants, which suggested that phytohormone are also required for the regulation of leaf and root. Comparison between control and transgenic rice overexpressing a CaMsrB2 gene, resulted in different pattern of ABA, JA levels under different stress condition. In both drought and salinity stresses, the expression of OsWRKY45 gene was similar in both treatments with time. These results suggest that gene involved in the plant physiology response in mechanism to abiotic stress.