title: Interference of allelopathic wheat with different weeds.
abstract: BACKGROUND
  Interference of allelopathic wheat with weeds involves a broad spectrum of species either independently or synergistically with competitive factors. This study examined the interference of allelopathic wheat with 38 weeds in relation to the production of allelochemical 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) in wheat with and without root-root interactions.
  
  
  RESULTS
  There were substantial differences in weed biomass and DIMBOA concentration in wheat-weed coexisting systems. Among 38 weeds, nine weeds were inhibited significantly by allelopathic wheat but the other 29 weeds were not. DIMBOA levels in wheat varied greatly with weed species. There was no significant relationship between DIMBOA levels and weed suppression effects. Root segregation led to great changes in weed inhibition and DIMBOA level. Compared with root contact, the inhibition of eight weeds was lowered significantly, while significantly increased inhibition occurred in 11 weeds with an increased DIMBOA concentration under root segregation. Furthermore, the production of DIMBOA in wheat was induced by the root exudates from weeds.
  
  
  CONCLUSIONS
  Interference of allelopathic wheat with weeds not only is determined by the specificity of the weeds but also depends on root-root interactions. In particular, allelopathic wheat may detect certain weeds through the root exudates and respond by increasing the allelochemical, resulting in weed identity recognition.
authors: College of Resources and Environmental Sciences, China Agricultural University, Beijing, China.
authors: Song-Zhu
authors: SZ
authors: Zhang
authors: College of Resources and Environmental Sciences, China Agricultural University, Beijing, China.
authors: Yong-Hua
authors: YH
authors: Li
authors: College of Resources and Environmental Sciences, China Agricultural University, Beijing, China.
authors: Chui-Hua
authors: CH
authors: Kong
authors: State Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin, China.
authors: Xiao-Hua
authors: XH
authors: Xu
mesh_terms: D064089:Allelopathy; D048588:Benzoxazines / Q000378:metabolism*; D018517:Plant Roots / Q000502:physiology; D057685:Plant Weeds / Q000502:physiology*; D013045:Species Specificity; D014908:Triticum / Q000502:physiology*
chemical_list: D048588:Benzoxazines; C050733:2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one
keywords: Triticum aestivum; allelochemical production; allelopathy; identity recognition; root segregation; root-root interactions