Assay of NPR1 gene expression in wheat under powdery mildew stress

Abstract

One of the effective plant disease management strategies is based on the employment of resistance inducers. In the present study, to assay, the effects of Salicylic acid (chemical inducer) and Piriformospora indica (biological inducer) on wheat powdery mildew (Blumeria graminnis f. sp. tritici), the expression rate of Non-expresser of pathogenesis-related genes1 (NPR1) genewas evaluated using qPCR. For this purpose, Falat and Tajan cultivars were selected as susceptible and resistant genotypes to powdery mildew, respectively. To evaluate the rate of gene expression, the P. indica colonized Falat along with mock plants were inoculated with Powdery mildew. In another experiment, Falat treated with SA and control plants were inoculated with Powdery mildew 48 h after treatment with SA. Gene expression was assayed in Falat compared with resistant cv. Tajan. Sampling was carried out at 0, 6, 12, 24 and 48 hours after infection. Comparisons of gene expression patterns showed that after infection, the expression levels of NPR1 increased in induced and non-induced Falat and Tajan cultivars. The maximum gene expression levels were observed at 24 hours post infection. But the expression levels of the gene at this timewere much higher in induced treatments compared with control. The current study showed that NPR1 can be involved in resistance strategy. Thus, using NPR1 gene as a desired gene in genetic engineering for increasing the potential of plant resistance to pathogens can be considered. Moreover, the high response of NPR1 gene in induced plants indicated that both SA and P. indica play a critical role in inducing resistance.

Keywords

• wheat
• resistance inducer
• piriformospora indica
• salicylic acid
• npr1 gene