Locoweed Endophytes: A Review

Locoweeds, which are a common name for poisonous species of the genera Astragalus and Oxytropis, are toxic leguminous plants through a symbiotic association with the fungal endophyte Alternaria section Undifilum. The fungus produces an indolizidine alkaloid, swainsonine, which causes a toxicosis of grazing animals, named locoism. By what means stress from environment or genetics of locoweed endophytes affect fungal growth and synthesis of swainsonine as well as how fungal endophyte synthesize swainsonine in locoweeds, in addition to disruption of the toxic alkaloid swainsonine in locoweed plants, have not been well identified. To answer the above questions, further research is needed as locoweed plants are most palatable to grazing animals especially when locoweed plants are at flowering stage. This review outlines the present situation on locoweed plants in China, production of swainsonine, detection and interaction of locoweed endophytes as well as their transmission within locoweed plants .