Bioassay for the Response of Resveratrol Transgenic Rice Lines to Bacterial and Fungal Diseases

Resveratrol is a stilbenoid and phytoalexin produced in response to stresses, such as wounding, and pathogen attacks by bacteria or fungi. Two resveratrol rice lines, Iksan515 and Iksan526, were used to examine resistance against Korean pathogen races for bacterial blight, leaf blast, and brown leaf spot. The screening test for bacterial blight demonstrated an increased susceptibility of both transgenic lines to K1 race, and a more susceptible Iksan515 to K2. Phenotypic evaluation for resistance to brown leaf spot also revealed the susceptibility of Iksan526 to the disease which did not significantly differ from the isogenic variety ‘Dongjin’, and a slightly more susceptible Iksan515 to the disease compared to check. When the lines were screened with three races (KJ301, KJ101 and KJ133) of leaf blasts in the field, both transgenic lines exhibited resistance but at the same level with ‘Dongjin’. Our overall findings suggest that foreign phytoalexin resveratrol production in transgenic rice lines transformed with resveratrol synthase gene did not confer resistance against fungal and bacterial diseases.