Novel Chitinase Gene from Indica Rice Tetep Provides Enhanced Resistance against Sheath Blight Pathogen in Rice.

Sheath blight disease (ShB), caused by the fungus Kühn, is one of the most destructive diseases of rice ( L.), causing substantial yield loss in rice. In the present study, a novel rice chitinase gene, was cloned from QTL region of tolerant rice line Tetep and used for functional validation by genetic transformation of ShB susceptible japonica rice line Taipei 309 (TP309). The transformants were characterized using molecular and functional approaches. Molecular analysis by PCR using a set of primers specific to CaMv 35S promoter, chitinase and genes confirmed the presence of transgene in transgenic plants which was further validated by Southern hybridization. Further, qRT-PCR analysis of transgenic plants showed good correlation between transgene expression and the level of sheath blight resistance among transformants. Functional complementation assays confirmed the effectiveness of the chitinase mediated resistance in all the transgenic TP309 plants with varying levels of enhanced resistance against . Therefore, the novel chitinase gene cloned and characterized in the present study from the QTL region of rice will be of significant use in molecular plant breeding program for developing sheath blight resistance in rice.