title: Allelochemicals in the rhizosphere soil of Euphorbia himalayensis.
abstract: Weed infestation has been known to cause considerable reductions in crop yields, thereby hindering sustainable agriculture. Many plants in genus Euphorbia affect neighboring plants and other organisms by releasing chemicals into the environment. In view of the serious threat of weeds to agriculture, the allelochemicals of Euphorbia himalayensis and their allelopathic effects were investigated. The extract of root exudates from rhizosphere soil exhibited allelopathic activities against crops (wheat, rape, and lettuce) and grasses (Poa annua, Festuca rubra, and red clover). Bioassay-guided fractionation and isolation from the root extract of E. himalayensis led to the characterization of two ellagic acid derivatives and a jatrophane diterpene, which observably showed phytotoxic activities against lettuce, Festuca arundinacea, and F. rubra. They were further confirmed by ultra-performance liquid chromatography-tandem mass spectrometry to have concentrations of 3.6, 3.8, and 8.99 nmol/g in the rhizospere soil, respectively. Bioassay indicated that the combination of the allelochemicals could be selective plant growth regulator in agriculture.
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources of the Chinese Academy of Sciences (CAS) and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences , Lanzhou, Gansu 730000, People's Republic of China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Liu
authors.forename: Dengxue
authors.initials: D
authors.lastname: Lu
authors.forename: Hui
authors.initials: H
authors.lastname: Jin
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Yan
authors.forename: Xiuzhuang
authors.initials: X
authors.lastname: Li
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Yang
authors.forename: Hongru
authors.initials: H
authors.lastname: Guo
authors.forename: Bo
authors.initials: B
authors.lastname: Qin
mesh_terms: D064089:Allelopathy; D001681:Biological Assay; D018556:Crops, Agricultural / Q000187:drug effects / Q000254:growth & development; D028481:Euphorbia / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D013058:Mass Spectrometry; D010675:Pheromones / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D053147:Plant Exudates / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D018517:Plant Roots / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity; D057685:Plant Weeds / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D058441:Rhizosphere; D012987:Soil / Q000737:chemistry
chemical_list: D010675:Pheromones; D053147:Plant Exudates; D012987:Soil