Identification and Characterization of Genes Responsible for Drought Tolerance in Rice Mediated by Pseudomonas fluorescens

Drought is one of the major abiotic stresses which adversely affect crop plants limiting growth and yield potential. Structural and functional characterization of drought stress-induced genes has contributed to a better understanding of how plants respond and adapt to the drought stress. In the present study, differential display technique was employed to study the gene expression of rice plants at the reproductive stage that were subjected to drought stress by withholding water, Pseudomonas fluorescens strain (Pf1) treated plants subjected for drought stress by withholding water and control (well-watered). Differentially expressed cDNAs of six genes (COX1, PKDP, bZIP1, AP2-EREBP, Hsp20 and COC1) were identified, cloned and sequenced. Real-time qPCR analysis showed that all the six genes were upregulated in drought-stressed plants treated with Pf1. This revealed that the remarkable influence of Pf1 colonization leads to drought tolerance at the reproductive stage. These results showed that high levels of gene expression in plants lacking adequate water can be remarkably influenced by Pf1 colonization, which might be a key element for induced systemic tolerance by microbes.