title: [Autotoxicity of aqueous extracts from plant of cultivated Astragalus membranaceus var. mongholicus].
abstract: OBJECTIVE
  To exploring the relationship between continuous cropping obstacle and autotoxicity of Astragalus membranaceus var. mongholicus, autotoxic effect of plant aqueous extract were determined.
  
  
  METHODS
  Distilled water (CK), aqueous extract of plant, including root, stem and leaf (12.5, 25, 50 and 100 mg/mL respectively)were applied to testing their effect on early growth of Astragalus membranaceus var. mongholicus. Specifically, seed germination rate, germination index, emergence rate, elongation of radical and embryo, and seedling vigor index were determined.
  
  
  RESULTS
  The aqueous extract of root, stem, and leaf at 25 mg/mL significantly inhibited the seed germination and seedling growth of Astragalus membranaceus var. mongholicus, and this inhibitory effect generally increased with the increase of the concentration of aqueous extracts. To the comprehensive allelopathic effect, the extracts from Astragalus membranaceus var. mongholicus stem were more inhibitory than those from leaf and root. The germination index and seedling vigor index were more sensitive to extract than other determined parameters.
  
  
  CONCLUSIONS
  Aqueous extracts from Astragalus membranaceus var. mongholicus plant gave inhibitory effects on Astragalus. membranaceus var. mongholicus germination and seedling growth, and this inhibitory effect generally increased with the increases of aqueous extract concentration at a certain ranges. In conclusion, there is an autotoxicity in continuous cropping of Astragalus membranaceus var. mongholicus.
authors.forename: Xin-Hui
authors.initials: XH
authors.lastname: Zhang
authors.forename: Duo-Yong
authors.initials: DY
authors.lastname: Lang
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Yun-Sheng
authors.initials: YS
authors.lastname: Zhao
authors.forename: Xiu-Li
authors.initials: XL
authors.lastname: Wu
authors.forename: Xue-Yan
authors.initials: XY
authors.lastname: Fu
mesh_terms: D027885:Astragalus propinquus / Q000737:chemistry* / Q000254:growth & development / Q000502:physiology*; D018525:Germination / Q000187:drug effects* / Q000502:physiology; D010936:Plant Extracts / Q000302:isolation & purification / Q000633:toxicity*; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D036226:Seedlings / Q000187:drug effects* / Q000254:growth & development
chemical_list: D010936:Plant Extracts