Expression of an endo α-1, 3-Glucanase gene from Trichoderma harzianum in rice induces resistance against sheath blight

Abstract

Transformation of rice was done through Agrobacterium mediated, utilizing a binary vector pBS, harboring a fungal gene endo α-1, 3-glucanase from Trichoderma harzianum under rice constitutive promoter actin2 and Agrobacterium nopaline synthase (nos) transcriptional terminator in a T-DNA. Likewise, a selectable marker gene hygromycin phosphotransferese (hpt) resistant to Hygromycin B was cloned in the middle of actin2 and nos terminator in a similar T-DNA. The expression of endo α-1, 3-glucanase was affirmed by cloning gfp gene after the fungal gene in the transformation DNA cassette. In the first generation of transgenic rice lines, out of 912 just 209 plants were false positive affirmed through PCR based screening for the transgene. The positive transgenic lines were tried with fungal infection by leaf cut test in vitro and foliar leaf shower technique in vivo. They demonstrated an exceptional protection against sheath blight disease. Further, seeds of all positive transgenic plants of the first generation were developed and screened in next generation. Just 62 plants were false positive out of 873 transgenic lines in this generation. In the comparative way, they were tried against the fungal disease and they demonstrated the exceptional protection once more. In this way, in this investigation, a fungal gene endo α-1, 3-glucanase was transformed into rice (IR 64) effectively which demonstrated protection against fungus Rhizoctonia solani.