title: Influence of endophyte genotype on swainsonine concentrations in Oxytropis sericea.
abstract: Locoism is a toxic syndrome of livestock caused by the ingestion of a subset of legumes belonging to the Astragalus and Oxytropis genera known as "locoweeds". Locoweeds contain the toxic indolizidine alkaloid swainsonine, which is produced by the endophytic fungi Undifilum species. Previously we reported that swainsonine concentrations differ between populations of Oxytropis sericea. We hypothesized that the genotype of the plant, endophyte, or an interaction of the two may be responsible for the differences in swainsonine concentration between populations of O. sericea. To test this hypothesis, plants derived from seeds collected at each location were grown in a common garden, Undifilum oxytropis isolates from each location were cultured and grown in a common environment, and a plant genotype by endophyte cross inoculation was performed. Here we show that the genotype of the endophyte is responsible for the differences in swainsonine concentrations observed in the two populations of O. sericea.
authors.affiliation: Poisonous Plant Research Laboratory, Agricultural Research Service, United States Department of Agriculture, 1150 E. 1400 N., Logan, UT 84341, USA. daniel.cook@ars.usda.gov
authors.forename: Daniel
authors.initials: D
authors.lastname: Cook
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Grum
authors.forename: Dale R
authors.initials: DR
authors.lastname: Gardner
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Welch
authors.forename: James A
authors.initials: JA
authors.lastname: Pfister
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry*; D018533:Biomass; D004247:DNA / Q000096:biosynthesis / Q000235:genetics; D017931:DNA Primers; D060026:Endophytes / Q000235:genetics*; D005838:Genotype; D033021:Oxytropis / Q000737:chemistry* / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D012639:Seeds / Q000737:chemistry; D017026:Swainsonine / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D017931:DNA Primers; D004247:DNA; D017026:Swainsonine