Grass-Endophyte Interactions and Their Associated Alkaloids as a Potential Management Strategy for Plant Parasitic Nematodes

• Published in: Toxins Vol. 16; no. 6; p. 274
• Main Authors: Mwangi, Nyambura G, Stevens, Mark, Wright, Alistair J D, Edwards, Simon G, Hare, Martin C, Back, Matthew A
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.06.2024; MDPI
• Subjects: Alkaloids; Alkaloids - pharmacology; Allelopathy; Animals; Biological activity; Biological control; Control; Drought; endophyte; Endophytes; Endophytes - metabolism; Environmental aspects; Epichloe - metabolism; Epichloë; Ergot; Ergot alkaloids; Fungi; Genotypes; Grasses; Heavy metals; Herbivores; Herbivory; Host plants; Host-bacteria relationships; induced resistance; Insects; Livestock; mechanisms; Metabolites; Mutualism; Nematoda; Nematoda - drug effects; Nematodes; Paralysis; Pests; Physiological aspects; Plant Diseases - microbiology; Plant Diseases - parasitology; Plant parasites; Poaceae - parasitology; Review; Seeds; Toxicity; Toxins; Waterlogging; United Kingdom; Europe; induced resistance; endophyte; mechanisms; Epichloë; alkaloids
• ISSN: 2072-6651; 2072-6651
• DOI: 10.3390/toxins16060274

Claviceptaceous endophytic fungi in the genus mostly form a symbiotic relationship with cool-season grasses. spp. are capable of producing bioactive alkaloids such as peramines, lolines, ergot alkaloids, and indole-diterpenes, which protect the host plant from herbivory by animals, insects, and nematodes. The host also benefits from enhanced tolerance to abiotic stresses, such as salt, drought, waterlogging, cold, heavy metals, and low nitrogen stress. The bioactive alkaloids produced can have both direct and indirect effects towards plant parasitic nematodes. Direct interaction with nematodes' motile stages can cause paralysis (nematostatic effect) or death (nematicidal effect). Indirectly, the metabolites may induce host immunity which inhibits feeding and subsequent nematode development. This review highlights the different mechanisms through which this interaction and the metabolites produced have been explored in the suppression of plant parasitic nematodes and also how the specific interactions between different grass genotypes and endophyte strains result in variable suppression of different nematode species. An understanding of the different grass-endophyte interactions and their successes and failures in suppressing various nematode species is essential to enable the proper selection of grass-endophyte combinations to identify the alkaloids produced, concentrations required, and determine which nematodes are sensitive to which specific alkaloids.