Enhancement of Tolerance to Sheath Blight in Indica Rice through Incorporation of Chitinase Genes

Abstract

Rice sheath blight, caused by Rhizoctonia solani, a polyphagous fungus, is a major disease on rice and causes up to 50% yield losses. Genetic enhancement of host plant disease resistance is an attractive solution to address diseases like sheath blight. The major problem associated with enhancement of host (rice) resistance to sheath blight through conventional approaches is the lack of resistant donors in the rice gene pool and only moderate levels of resistance is available. In this study, an attempt was made to enhance host plant resistance through incorporation of a chitinase gene employing biolistic approach. The incorporation of the transgene was confirmed through molecular analyses like PCR and Southern assays. The results of the bioassay studies against the pathogen Rhizoctonia solani did indicate higher levels of resistance moreover the inheritance pattern of the transgene was Mendelian. The transgenics generated did show high promise and can provide a practical solution to tackle sheath blight, a major disease on rice.