title: Phytotoxicity of antofine from invasive swallow-worts.
abstract: Pale swallow-wort (Vincetoxicum rossicum) and black swallow-wort (V. nigrum) are two emerging invasive plant species in the northeastern United States and southeastern Canada that have shown rapid population expansion over the past 20 years. Using bioassay-guided fractionation, the known phytochemical phenanthroindolizidine alkaloid, (-)-antofine, was identified as a potent phytotoxin in roots, leaves, and seeds of both swallow-wort species. In seedling bioassays, (-)-antofine, at μM concentrations, resulted in greatly reduced root growth of Asclepias tuberosa, A. syriaca, and Apocynum cannabinum, three related, native plant species typically found in habitats where large stands of swallow-wort are present. In contrast, antofine exhibited moderate activity against lettuce, and it had little effect on germination and root growth of either black or pale swallow-wort. In disk diffusion assays, antifungal activity was observed at 10 μg and 100 μg, while antibacterial activity was seen only at the higher level. Although both swallow-wort species display multiple growth and reproductive characteristics that may play an important role in their invasiveness, the presence of the highly bioactive phytochemical (-)-antofine in root and seed tissues indicates a potential allelopathic role in swallow-worts' invasiveness.
authors: USDA, Agricultural Research Service, Biological Integrated Pest Management Research Unit, Robert W. Holley Center for Agriculture and Health, Tower Road, Ithaca, NY 14853, USA. Donna.Gibson@ars.usda.gov
authors: Donna M
authors: DM
authors: Gibson
authors: Stuart B
authors: SB
authors: Krasnoff
authors: Jeromy
authors: J
authors: Biazzo
authors: Lindsey
authors: L
authors: Milbrath
mesh_terms: D030010:Apocynum / Q000254:growth & development; D031108:Asclepias / Q000254:growth & development; D007211:Indoles / Q000633:toxicity*; D018545:Lactuca / Q000254:growth & development; D010618:Phenanthrolines / Q000633:toxicity*; D010936:Plant Extracts / Q000633:toxicity*; D057685:Plant Weeds / Q000633:toxicity*
chemical_list: D007211:Indoles; D010618:Phenanthrolines; D010936:Plant Extracts; C473343:antofine