Location: Hard Winter Wheat Genetics ResearchTitle: Indirect Plant Defense against Insect Herbivores: A Review Author
Submitted to: Review Article
Publication Type: Review Article
Publication Acceptance Date: 3/20/2017
Publication Date: N/A
Citation: N/A Interpretive Summary: Insects are one of the biggest constraints on plant productivity. Plants respond to insect attack by launching two types of defenses: direct defense and indirect defense. Direct defense includes all plant responses that suppress attacking insects by directly affecting the physiology and/or behavior of the attackers. Indirect defense includes all plant traits that by themselves do not affect host resistance, but can attract natural enemies of the attacking insects and thus reduce plant loss. This paper provides a detailed review of current literature on plant indirect defense. A better understanding of indirect plant defense may lead to novel cost-effective insect control strategies.
Technical Abstract: Plants respond to herbivore attack by launching two types of defenses: direct defense and indirect defense. Direct defense includes all plant traits that increase the resistance of host plants to attacking insect herbivores by affecting the physiology and/or behavior of the attackers. Indirect defense includes all traits that by themselves do not affect the resistance of host plants, but can attract natural enemies of the attacking insects and thus reduce plant loss. When plants recognize herbivore-associated elicitors, they produce and release a blend of volatiles that can attract predators, parasites, and fungivores. Known herbivore-associated elicitors include fatty acid-amino acid conjugates, sulfur-containing fatty acids, fragments of cell walls, peptides, esters, and enzymes. Identified plant volatiles include terpenes, nitrogenous compounds, and indoles. In addition, extrafloral nectars, food bodies, and domatia can also attract natural enemies and provide food and shelter to carnivores. A better understanding of indirect plant defense at the molecular level may lead to novel control measures such as enhanced biological control using volatile-based attractants of natural enemies.