title: [Research on growth state and physiological changes of Tianquan Bergenia purpurascens under different shade conditions].
abstract: OBJECTIVE
  To study the growth index and physiological index of Tianquan Bergenia purpurascens under different shade conditions (100%, 80%, 60%, 40%, 20%), and investigate its adaptation mechanism to shade environment so that it can provide theoretical basis for cultivation and production.
  
  
  METHODS
  The growth index such as the length, the width and the number of new leaves, and leaf area, fresh weight, dry weight and specific leaf weight of the samples which were collected from the beginning of March to late May under different shade conditions were measured. The physiological index including the contents of photosynthetic pigments, MDA, soluble sugar, soluble protein, proline and the activity of SOD were measured all together.
  
  
  RESULTS
  The growth and morphological index under light intensity 100%-60% were higher than those under light intensity 40%-20%. And except specific leaf weight, the growth and morphological index were significantly higher under light intensity 60% than those under the other shade conditions; The contents of Chla, Chlb, Chl (a + b) and Car under light intensity 100%-60% were higher than those under light intensity 40%-20%, while Chla/b was higher under light intensity 40%-20%; The activity of SOD, soluble sugar, soluble protein and proline contents were higher under light intensity 100%-60%, while MDA content was higher under light intensity 40%-20%. Chl(a+b) content, soluble sugar content and activity of SOD were the highest under light intensity 60%, but MDA content was the lowest.
  
  
  CONCLUSIONS
  Sixty percent irradiance treatment was the most favorable to the growth of Tianquan B. purpurascens; 100%-80% irradiance treatments were favorable to its growth; 40%-20% irradiance treatment was negative for its growth.
authors.affiliation: China West Normal University, Key Laboratory of Southwest China Wildlie Resources Conservation, Nanchong 637000, China. yx_li@263.net
authors.forename: Yunxiang
authors.initials: Y
authors.lastname: Li
authors.forename: Xingli
authors.initials: X
authors.lastname: Liao
authors.forename: Qiumei
authors.initials: Q
authors.lastname: Quan
mesh_terms: D002734:Chlorophyll / Q000032:analysis / Q000378:metabolism; D008027:Light; D010788:Photosynthesis; D010936:Plant Extracts / Q000032:analysis / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects; D031995:Saxifragaceae / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects*
chemical_list: D010936:Plant Extracts; D002734:Chlorophyll