Agent for stimulating the natural defenses of plants, useful as antiviral, antibacterial, antifungal and insecticide, comprises curdlan sulfate

摘要

Agent (A) for stimulating the natural defense mechanisms of agricultural or ornamental plants comprises curdlan sulfate (I) with degree of sulfatation 1-2, preferably 1.5. ACTIVITY : Plant Antiviral; Plant Antibacterial; Plant Antifungal; Insecticide. Nicotiana tabacum cv. Samsun H plants were challenged with tobacco mosiac virus, then after an unspecified time, the number and size of viral lesions were determined. For plants treated with water only, the mean size was 1.61 mm and the number about 350, but for plants that had been treated with a 200 mu g/ml solution of (I) the corresponding figures were 0.43 mm and about 90. MECHANISM OF ACTION : Stimulating production of protective amtimicrobial PR proteins (e.g. chitinase and gluconase) and of antibiotics, e.g. scopoletin (in tobacco).