Bioactive natural products in plant disease control
Gwinn, K. D.  2018.  Studies in Natural Product Chemistry, Studies in Natural Products Chemistry Vol. 56:229-246. Copyright: Elsevier 2018 Published: 1st February 2018 Elsevier Editors: Atta-ur-Rahman.

Increasing sustainability of agricultural production systems increases availability of safe and nutritious food thus addressing the grand agricultural challenge of food security. Sustainability can be incorporated into plant production by expanded use of bioactive natural products for plant protection. In both ancient and modern agriculture compounds derived from plants and microorganisms have been used as biopesticides to reduce impact of disease in plant production. This review will focus on the use of microbial or botanical natural products that act as antimicrobial agents and/or as natural inducers of the host defense system. Commercial products based on extracts of plants (particularly neem, citrus, and Giant Knotweed), proteins from plant pathogens, and mixes of oils derived from herbs and seeds are available for producers. Some products act directly on the fungus, and others stimulate the innate immunity system of the host plant. Antifungal activity of extracts and essential oils is an active area of research, and much discovery-based research is conducted to determine novel chemical combinations or to discover value-added roles for waste streams in plant-based industries. Chemical basis of antifungal activity is not always determined, but active fractions typically include phenolics, flavones, quinones, tannins, terpenes, essential oils, alkaloids, and saponins. Impact of these compounds on fungal growth will be discussed, and available literature on use of these compounds in plant protection formulations will be addressed. Application of basic knowledge to develop innovative control strategies (e.g., biopesticides that turn on plant resistance, plants engineered to overproduce bioactive natural products or produce antimicrobial proteins) will also be discussed. Keywords: