Variation Of Camptothecin Content During The Seeds Germination And Seedlings Development Of Camptotheca Acuminata

Camptothecin is an important defensive chemical in Camptotheca acuminata. We systematically analyze the variation in camptothecin during the process of seed germination, the formation of the seedling, and the development of the saplings. From the seed germination to the formation of the seedlings of C. acuminata, CPT content in endosperm was always in a really high level, while that in other parts varied with the plants development. The camptothecin content was higher in the younger tissue than in elder, otherwise that in cotyledon was highest when the seedlings were 9-15 days old. The camptothecin content were highest in youngest leaves(can be above 4‰o), and the highest contents in others parts were similarly about 1‰, but that in roots was about 0.2‰ equal to the lowest content in other parts. The results show that there is an evident juvenile defense strategy in the seeds of C. acuminata. Difference which the change causes of period is obvious weaker than development of difference that the organ causes. The role of camptothecin in seed is mainly undertaking the task of the chemical defence when the physics defence capability of the plant has not perfected yet.