Detection of swainsonine-producing endophytes in Patagonian Astragalus species

Swainsonine has been identified as the toxin in legumes belonging to the genera Astragalus and Oxytropis throughout the world including China, North America, and South America. Several South American Astragalus species have been reported to contain swainsonine; however, data is lacking to support th...

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Detalles Bibliográficos
Autores principales: Martinez, Agustin, Robles, Carlos Alejandro, Roper, Jessie M., Gardner, Dale R., Neyaz, Marwah S., Joelson, Natalia Zoe, Cook, Daniel
Formato: Artículo
Lenguaje:Inglés
Publicado: Elsevier 2019
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12123/6518
https://www.sciencedirect.com/science/article/pii/S0041010119304702
https://doi.org/10.1016/j.toxicon.2019.09.020
Descripción
Sumario:Swainsonine has been identified as the toxin in legumes belonging to the genera Astragalus and Oxytropis throughout the world including China, North America, and South America. Several South American Astragalus species have been reported to contain swainsonine; however, data is lacking to support the presence of a fungal symbiont in South American Astragalus species as has been shown for North American and Chinese Astragalus and Oxytropis species. The objective of this study was to investigate several South American species that have been reported to contain swainsonine for the presence of the fungal symbiont using culturing and PCR. Swainsonine was detected in field collections of A. pehuenches, A. illinii and A. chamissonis but not A. moyanoi, which is consistent with reports of toxicity regarding these species. The symbiont Alternaria section Undifilum was detected by PCR in all three species that contained swainsonine but not in A. moyanoi. A fungal symbiont was isolated from seeds of Astragalus pehuenches and A. illinii. The isolated symbiont from both respective species produced swainsonine in vitro, and was demonstrated to belong to the genus Alternaria section Undifilum by analysis of the nuclear ribosomal DNA. It is highly likely that Alternaria section Undifilum isolates will be associated with other South American Astragalus species that are reported to contain swainsonine.