Soybean plants expressing an active oligomeric oxalate oxidase from the wheat gf-2.8 (germin) gene are resistant to the oxalate-secreting pathogen Sclerotina sclerotiorum
Source: Physiological and Molecular Plant Pathology, Volume 59, Number 6, December 2001 , pp. 297-307(11)
Publisher: Academic Press
Abstract:Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum (Lib.) De Bary is a serious fungal disease of soybean. Senescing petals provide a starting nutrient source for the invasion of healthy tissue by the advancing oxalic acid secreting fungal hyphae. Since oxalic acid is a major pathogenicity factor of SSR, transgenic soybean capable of degrading oxalic acid may be resistant to the pathogen. Transgenic soybean plants were produced byAgrobacterium -mediated transformation with the wheat germin gene (gf-2.8) encoding an oligomeric protein, oxalate oxidase (OxO), which oxidizes oxalic acid to carbon dioxide and hydrogen peroxide (H2O2). Transgenic soybean homozygous for 35S- gf-2.8 produced an approx. 130 kDa protein indistinguishable from wheat germin, and with OxO activity. OxO activity was prominent in cell walls proximal to the site of pathogen attack. The transgenics had greatly reduced disease progression and lesion length following cotyledon and stem inoculation with S. sclerotiorum indicating that the germin gene product conferred resistance to SSR. This is the first report of plant resistance to the fungal pathogen S. sclerotiorum in transgenic plants expressing OxO.
Document Type: Research Article
Affiliations: 1: Eastern Cereal and Oilseed Research Centre (ECORC), Agriculture and Agri-Food Canada, C.E.F, Building 21, Ottawa, Ontario, K1A OC6, Canada 2: Greenhouse and Processing Crops Research Centre (GPCRC), Agriculture and Agri-Food Canada, Harrow, Ontario, N0R 1G0, Canada 3: Department of Biochemistry, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
Publication date: December 2001