Chin J Plan Ecolo ›› 2010, Vol. 34 ›› Issue (6): 687-694.DOI: 10.3773/j.issn.1005-264x.2010.06.008

• Research Articles • Previous Articles     Next Articles

Effect of inoculation time on camptothecin content in arbuscular mycorrhizal Camptotheca acuminata seedlings

YU Yang; YU Tao; WANG Yang; and YAN Xiu-Feng*   

  1. Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field (Northeast Forestry University), Ministry of Education, Northeast Forestry University, Harbin 150040, China
  • Received:2009-07-07 Online:2010-06-01 Published:2010-06-01
  • Contact: YAN Xiu-Feng

Abstract: Aims Arbuscular mycorrhizal fungi can directly or indirectly affect plant secondary metabolic processes. Camptothecin, a secondary metabolite in a special Chinese tree Camptotheca acuminata, has gained great attention for its remarkable inhibitory activity against tumor cells. The effect of two arbuscular mycorrhizal fungi belonging to two genera on the accumulation of camptothecin at different growth times of C. acuminata seedling was carried out in the present study.
Methods The selected sterile seeds of C. acuminata were sown in sterilized matrix (a mixture of soil and sand) in the greenhouse. Seedlings with similar height and crown were selected and divided into three groups (30 pots per group). Each group of C. acuminata seedlings was inoculated with a species of arbuscular mycorrhizal fungi Acaulospora mellea or Glomus intraradices, or non-mycorrhizal inoculation when seedlings unearthed 20 days, 40 days and 60 days, respectively. After 30 days of treatment, camptothecin contents and yields in the seedlings of C. acuminata were determined.
Important findings All inoculated seedlings were infected by arbuscular mycorrhizal fungi and formed arbuscular mycorrhiza after 30 days of co-cultivation. The results showed that camptothecin yields (camptothecin contents multiplied by biomass) in mycorrhizal seedlings were significantly higher than non-mycorrhizal seedlings. Furthermore, the increase of camptothecin yields in mycorrhizal seedlings was mainly credited to the increase of camptothecin contents in seedlings (especially in leaves) inoculated at early stage (20 days of seedlings emergence) or to the increase of plant biomass in seedlings inoculated at late stage (60 days of seedlings emergence).