Expression of antimicrobial peptide snakin-1 confers effective protection in rice against sheath blight pathogen, Rhizoctonia solani

Abstract

Rice sheath blight disease caused by the necrotrophic fungus Rhizoctonia solani, is an economically detrimental fungal disease which significantly affects rice productivity worldwide. Potato snakin-1, a cysteine-rich basic antimicrobial peptide (AMP), is a member of the novel Snakin AMP family. In order to assess the ability of the snakin-1 peptide in protecting rice against the sheath blight disease, we have developed transgenic rice constitutively expressing the snakin-1 peptide. The antimicrobial activity of snakin-1 was evaluated against the sheath blight pathogen Rhizoctonia solani both in vitro and in planta. Crude protein from transgenic rice leaves showed in vitro antifungal activity against Rhizoctonia solani. Moreover, in planta bioassay results also confirmed the same, wherein snakin-1 expressing rice plants showed significantly enhanced protection against the sheath blight disease. This report demonstrates how a member of the Snakin family of antimicrobial peptides has been successfully used to generate sheath blight resistance in rice, without compromising on its agronomic characteristics and at no phenotypic cost.