EXPRESSION OF THIONIN AND PDF1.2 CODING GENES AS ANTIMICROBIAL POLYPEPTIDES IN INTERACTION OF RICE AGAINST RICE BLAST AGENT, MAGNAPORTHE ORYZAE

Thionins and defensins are small (5kDa)، basic، cysteine–rich polypeptides with antifungal properties. In this study، expression of Thionin and PDF1. 2 genes after inoculation of Magnaporthe oryzae to cultivars Khazar (resistant) and Tarom (susceptible) was analyzed. The treatments were subjected to Quantitative Real-time PCR at different times (from 0 to 96 hours after inoculation، hai). The peak expression of PDF1. 2 gene in both cultivars was at 24 hai (about 20 fold of 0 hai). Expression of Thionin gene showed a peak at 48 hai (about 8 fold of 0 hai). Expression profiles of both tested genes were more and less similar in both cultivars but the transcript level of Khazar was higher than Tarom. T-Student’s analysis of data showed significant differences between two cultivars (P values of <0. 05). The results showed that these antimicrobial polypeptides can play an important role in resistance of cv. Khazar against rice blast fungus، M. oryzae.