Chitosan Oligomers and Copper Sulfate Induce Grapevine Defense Reactions and Resistance to Gray Mold and Downy Mildew

Abstract

Chitosan (CHN), a deacetylated derivative of chitin, was shown to be efficient in promoting plant defense reactions. CHN oligomers of different molecular weight (MW) and degree of acetylation (DA) triggered an accumulation of phytoalexins, trans- and cis-resveratrol and their derivatives epsilon-viniferin and piceid, in grapevine leaves. Highest phytoalexin production was achieved within 48 h of incubation with CHN at 200 mug/ml with an MW of 1,500 and a DA of 20% (CHN1.5/20), while oligomers with greater MW were less efficient, indicating that a specific MW threshold could be required for phytoalexin response. Treatment of grapevine leaves by highly active CHN1.5/20 also led to marked induction of chitinase and beta-1,3-glucanase activities. CHN1.5/20 applied together with copper sulfate (CuSO(4)) strongly induced phytoalexin accumulation. CuSO(4) alone, especially at low concentrations also elicited a substantial production of phytoalexins in grapevine leaves. Evidence is also provided that CHN1.5/20 significantly reduced the infection of grapevine leaves by Botrytis cinerea and Plasmopara viticola, and in combination with CuSO(4) conferred protection against both pathogens.

Biological and Chemical Resistance Inducers Approaches for Controlling Foliar Diseases of Some Vegetables under Protected Cultivation System

“…These data also confirm earlier studies which showed that saccharin treatment primed CAD activity in barley against subsequent challenge with powdery mildew [65]. As for Chiosan, in recent years, the importance of chitosaccha-rides as plant growth promoting and disease control agents has been emphasized [67,68]. CHN (β-1-4 linked N-gluco-samine) has been shown to induce defense responses in different plants [69,70].…”

“…CHN (β-1-4 linked N-gluco-samine) has been shown to induce defense responses in different plants [69,70]. Chitosan oligomers was found to induce defense responses in grapevine leaves, as evidenced by an accumulation of stilbene phytoalexins, trans-and cis-resveratrol, ε-viniferins, and piceids, and a stimulation of chitinase and β-1,3-glucanase activities [68]. They added that the combination of Chitosan and CuSO 4 increased phytoalexin production.…”

A Review of the Applications of Chitin and Its Derivatives in Agriculture to Modify Plant-Microbial Interactions and Improve Crop Yields

“…Soil amendment with chitosan has repeatedly been shown to control fungal diseases in numerous crops, especially Fusarium wilts [31][32][33] and grey mould [34,35]. It is also of note that these studies show chitosan to be fungistatic against both biotrophic and necrotrophic pathogens.…”

Preparation and Foliar Application of Oligochitosan - Nanosilica on the Enhancement of Soybean Seed Yield

“…These features, together with their biocompatibility, biodegradability, and nontoxicity make them as interesting biopolymers for application in medicine, cosmetic, biotechnology, food and agriculture, etc. Oligochitosan is effective at eliciting plant innate immunity against disease in plant such as tomato [6], grapevine [7], etc. Therefore, Yin et al (2010) supposed oligochitosan as a plant vaccine that is similar with general animal vaccine [8].…”