In vivo assessment of plant extracts for control of plant diseases: A sesquiterpene ketolactone isolated from Curcuma zedoaria suppresses wheat leaf rust

• Published in: Journal of environmental science and health. Part B, Pesticides, food contaminants, and agricultural wastes Vol. 53; no. 2; pp. 135 - 140
• Main Authors: Han, Jae Woo, Shim, Sang Hee, Jang, Kyoung Soo, Choi, Yong Ho, Dang, Quang Le, Kim, Hun, Choi, Gyung Ja
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 01.02.2018; Taylor & Francis Ltd
• Subjects: Acetates - chemistry; Acetic acid; Active control; Agrochemicals; Antifungal activity; Basidiomycota - drug effects; Basidiomycota - pathogenicity; Blight; Chlorides; Curcuma - chemistry; Curcuma zedoaria; Dichloromethane; Disease control; Ethyl acetate; Fungicides; Fungicides, Industrial - chemistry; Fungicides, Industrial - pharmacology; Hexanes; in vivo antifungal activity; In vivo methods and tests; Lactones - chemistry; Lactones - isolation & purification; Lactones - pharmacology; Late blight; Leaf rust; Leaves; Lycopersicon esculentum - microbiology; Methanol; Methanol - chemistry; Molecular Structure; n-Hexane; NMR; Nuclear magnetic resonance; Organic Agriculture - methods; Organic farming; Oryza - microbiology; Pathogens; Pesticides; Plant diseases; Plant Diseases - prevention & control; Plant extracts; Plant Extracts - chemistry; Plant Extracts - pharmacology; Rhizoctonia - drug effects; Rhizoctonia - pathogenicity; Rhizome - chemistry; Rhizomes; sesquiterpene ketolactone; Sesquiterpenes - chemistry; Sesquiterpenes - isolation & purification; Sesquiterpenes - pharmacology; Sheath blight; Solvents - chemistry; Tomatoes; Triticum - microbiology; Wheat; wheat leaf rust; Curcuma zedoaria; wheat leaf rust; in vivo antifungal activity; sesquiterpene ketolactone; Plant extracts
• ISSN: 0360-1234; 1532-4109
• DOI: 10.1080/03601234.2017.1397448

As an alternative to synthetic pesticides, natural materials such as plant extracts and microbes have been considered to control plant diseases. In this study, methanol extracts of 120 plants were explored for in vivo antifungal activity against Rhizoctonia solani, Botrytis cinerea, Phytophthora infestans, Puccinia triticina, and Blumeria graminis f. sp. hordei. Of the 120 plant extracts, eight plant extracts exhibited a disease control efficacy of more than 90% against at least one of five plant diseases. In particular, a methanol extract of Curcuma zedoaria rhizomes exhibited strong activity against wheat leaf rust caused by P. triticina. When the C. zedoaria methanol extracts were partitioned with various solvents, the layers of n-hexane, methylene chloride, and ethyl acetate showed disease control values of 100, 80, and 43%, respectively, against wheat leaf rust. From the C. zedoaria rhizome extracts, an antifungal substance was isolated and identified as a sesquiterpene ketolactone based on the mass and nuclear magnetic resonance spectral data. The active compound controlled the development of rice sheath blight, wheat leaf rust, and tomato late blight. Considering the in vivo antifungal activities of the sesquiterpene ketolactone and the C. zedoaria extracts, these results suggest that C. zedoaria can be used as a potent fungicide in organic agriculture.