Thiosulphonate-rhamnolipid-glycanic complexes as inducers of virus resistance in hypersensitive plants

Abstract

Involving the natural host-resistance mechanisms to pathogens are essential and one of the most promising approaches in development of first-line defenses against viral plant diseases. Polysaccharides isolated from natural sources are considered the most active resistance inducers. The biological activity of polysaccharides depends on the nature and chemical structure of the constituent components of complex preparations. In this view, the objective of our study was to evaluate the biological activity of complex preparations composed of glycans, rhamnolipids, and thiosulfonates as inducers of natural plant resistance and inhibitors of tobacco mosaic virus (TMV). Complex preparations were obtained using the following components: biogenic glycolipids - rhamnolipids of the Pseudomonas sp. strain PS-17, glycans - Ganoderma adspersum glucan and Candida maltosa mannan, as well as synthetic biocides - thiosulfonates (methylthiosulfanilate). The biological activity of the preparations was investigated in the host-virus model system Nicotiana tabacum L. and TMV. It was shown that preparations at concentrations of 10 and 100 μg mL-1 were active plant resistance inducers in N. tabacum cv. Immune 580, hypersensitive to TMV. At the same concentrations, complex preparations also reduced infectivity of TMV on Datura metel L. acting as viral infection inhibitors. The inducing activity of the complex preparations is sensitive to well-known transcription inhibitor actinomycin D (10 μg mL-1). This fact may indicate the important role of RNA synthesis in the activation of plant virus resistance by the studied preparations.

Keywords

• datura metel
• glycans
• glycolipids
• liposomes
• nicotiana tabacum
• thiosulfonates