title: [Dynamic research of density on Platycodon grandiflorum dry material accumulation and platycodin D content in Platycodon grandiflorum].
abstract: OBJECTIVE
  To study the dynamic changes of dry material accumulation and platycodin D content in Platycodon grandiflorum in different planting densities.
  
  
  METHODS
  Five different planting densities M1 (4 cm x 25 cm), M2 (6 cm x 25 cm), M3 (8 cm x 25 cm), M4 (10 cm x 25 cm) and M5 (12 cm x 25 cm) were designed in the plot experiment. The individual and colony biomass accumulation, dry material distribution, root yield and platycodin D content were measured in different stage.
  
  
  RESULTS
  In a certain density range the individual biomass in P. grandiflorum obviously declined with increasing density with the exception of biomass M2 > biomass M3. On the contrary, the colony biomass increased with the increasing density. Dry material accumulation in each organ in P. grandiflorum in different planting densities showed significance (P<0.05). The dry material distribution in organs in the different planting densities showed significance (P<0.05), and the dry material distribution in flower and fruit reached the minimal level in M2, in the same planting density the distribution in root reached the maximal; The dry material in stem, flower and fruit obviously declined with the increasing density, while the dry material in leaf increased. The individual root output increased with the increasing density, and it reached the highest in M2. The colony root yield increased with the increasing density. The platycodin D content in P. grandiflorum reached the highest in M2.
  
  
  CONCLUSIONS
  The result showed that a suitable planting density is very important to P. grandiflorum dry material accumulation and distribution, root yield, platycodin D content and colony yield.
authors.affiliation: College of Agronomy, Shandong Agricultural University, Taian 271018, China.
authors.forename: Huiyun
authors.initials: H
authors.lastname: Geng
authors.forename: Jianhua
authors.initials: J
authors.lastname: Wang
authors.forename: Aimin
authors.initials: A
authors.lastname: Cai
authors.forename: Hongying
authors.initials: H
authors.lastname: Zhou
authors.forename: Qiting
authors.initials: Q
authors.lastname: Dong
authors.forename: Yinshi
authors.initials: Y
authors.lastname: Sun
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Xue
authors.forename: Xiaochong
authors.initials: X
authors.lastname: Ma
authors.forename: Sha
authors.initials: S
authors.lastname: Liu
mesh_terms: D018514:Plant Structures / Q000254:growth & development / Q000378:metabolism; D031238:Platycodon / Q000254:growth & development* / Q000378:metabolism*; D012503:Saponins / Q000378:metabolism*; D012621:Seasons; D014315:Triterpenes / Q000378:metabolism*
chemical_list: D012503:Saponins; D014315:Triterpenes; C108953:platycodin D