喜树枝叶采收型品系海喜1号喜树碱的组织分布特征研究

Distribution characteristics of camptothecin in branches and leaves of harvest pattern Camptotheca acuminata ‘Hisun-Ⅰ’

目的研究喜树枝叶采收型品系海喜1号喜树碱的组织分布特征,为合理利用提取依据。方法以四川种源的普通喜树为对照,采用高效液相色谱法,检测了喜树品系——海喜1号各器官不同组织部位喜树碱的量。结果各器官不同组织部位,海喜1号喜树碱量普遍高于普通喜树,特别是半木质化枝条韧皮部显著高于普通喜树(P<0.01),幼叶喜树碱量显著高于普通喜树(P<0.05);不同品系的喜树均表现出幼嫩枝叶喜树碱量高于成熟组织的特点,但喜树碱在不同器官的组织分布模式并不相同,幼嫩器官和主根为离心式分布,而成熟器官(木质化枝条、主干)是向心式分布。结论海喜1号具有枝叶一年多次、连年采收利用模式的种质类型,喜树碱在海喜1号中的这种分布模式反映了喜树碱化学防御功能作用的转变。

Objective To study the tissue distribution characteristics of harvest pattern camptothecin （CPT） in branches and leaves of Camptotheca acuminata ＂Hisun- Ⅰ＂ （HI）. Methods Taking the variety of C. acuminata originally from Sichuan Province （SC） as control, the contents of CPT in different tissues of the organs in C. acuminata HI were detected by HPLC. Results In the different tissues, the CPT level in C. acuminata of HI was higher than that in C. acuminata of SC, especially in the semi-lignified branch of phloem （P〈0. 01） and young leaves （P〈0.05）. All the different strains of C. acuminate showed that the contents of CPT in young leaves and branches are higher than those in mature tissue, but the distribution pattern of CPT in the different tissues of organs was distinct. In the tender organs and main roots, the distribution was in an efferent way and in the lignified branch and main stem organs, the distribution was in an afferent model . Conclusion The line of HI is the germ plasm type suitable for multiple times in one year and consecutive years for harvest. The distribution pattern of CPT in HI might be correlated with the transformation of chemical defense function of CPT in different phases and organs.