Transgenic Plants with Enhanced Resistance to the Fungal Pathogen Rhizoctonia solani

Abstract

The production of enzymes capable of degrading the cell walls of invading phytopathogenic fungi is an important component of the defense response of plants. The timing of this natural host defense mechanism was modified to produce fungal-resistant plants. Transgenic tobacco seedlings constitutively expressing a bean chitinase gene under control of the cauliflower mosaic virus 35S promoter showed an increased ability to survive in soil infested with the fungal pathogen Rhizoctonia solani and delayed development of disease symptoms.

Benzothiadiazole induces disease resistance in Arabidopsis by activation of the systemic acquired resistance signal transduction pathway

“…The mRNAs that encode these proteins have been shown to accumulate coordinately in both a temporal and a spatial manner that is consistent with a role for these gene products in SAR (Ward et aL, 1991). In support of this idea, transgenic plants that overexpress various PR genes exhibit enhanced disease resistance Broglie et al, 1991;Liu et al, 1995). It has been proposed that a clear understanding of the basic mechanism that leads to the establishment of SAR may impact disease control practices by providing either genetically engineered plants with enhanced disease tolerance or novel mode-of-action chemicals .…”

Calcium Requirement for Ethylene-Dependent Responses.

“…Some of the PR proteins have well-defined enzymatic activities such as chitinase (Legrand et al, 1987), which catalyzes the hydrolysis of chitin, a major component of cell walls of many filamentous fungi (Aronson, 1965). Indeed, transgenic plants constitutively expressing chitinase show increased resistance to a fungal pathogen (Broglie et al, 1991). Chitinase expression, as a subset of the pathogenesis response, is induced by the presence of pathogens and directly by ethylene.…”

Purification, characterization of a CkChn134 protein from Cynanchum komarovii seeds and synergistic effect with CkTLP against Verticillium dahliae

“…The antifungal activity assay in vitro and determination of IC 50 were performed as previously described. 13 The conidial suspensions of V. dahliae were prepared from a culture grown for 5 days at 25 C in Czapek liquid medium (NaNO 3 2 g, K 2 HPO 4 1 g, MgSO 4 .7H 2 O 0.5 g, KCl 0.5 g, FeSO 4 0.01 g, sucrose 30 g, distilled water 1 L, and pH 7.2). All fungi were used for the detection of antifungal proteins in vivo.…”

“…For example, overexpression of a bean vacuolar chitinase gene in tobacco and canola increased ability to survive in soil infected by Rhizoctonia solani and delayed development of disease symptoms. 4 Overexpression of chitinase of barley enhanced resistance to powdery mildew infection in transgenic wheat. 5 To effectively inhibit fungal growth and significantly enhance protection against fungal attack in plants, expression of chitinase genes in combination with other PR-proteins has been reported, which indicated synergistic protective interaction of the coexpressed antifungal proteins.…”