喜树快速繁殖与再生体系建立

Rapid Propagation and Plantlet Regeneration of Camptotheca acuminata

喜树 (Camptothecaacuminata)是珙桐科 (Nyssaceae)的一种落叶阔叶树 ,为我国南方特有树种 ,含有抗肿瘤作用的喜树碱。本研究建立了喜树愈伤诱导 ,器官发生与植株再生体系以及喜树成年茎段和无菌苗子叶节的快繁体系。以喜树无菌苗子叶和胚轴为外植体 ,采用不同激素组合诱导愈伤组织 ,只有培养在NN6 9+6 -BA (1 0mg/L) +IAA (0 0 5mg/L) +AS (afeninesulfate ,10mg/L)的培养基上的愈伤组织出现器官分化。每个愈伤分化的芽数平均为 6个 ,分化率达 86 %。培养在附加 0 5mg/L的 6 -BA和 0 1mg/L的KT的NN6 9培养基上的芽生长既快又好。以子叶节和茎段为外植体 ,附加 6 -BA(0 5mg/L) ,IAA (0 1mg/L)的NN6 9培养基对喜树茎段丛生芽的诱导效果较好 ,子叶节丛生芽诱导培养基为NN6 9附加 6 -BA (0 2mg/L) ,IBA (0 0 5mg/L) ,AS (afeninesulfate ,10mg/L) ,附加 6 -BA(0 2 5mg/L) ,IAA (0 0 5mg/L)的培养基对丛生芽增殖效果明显。所诱导的芽苗在附加 0 5mg/LIBA ,0 1mg/LKT ,10mg/LAS的B5培养基上诱导生根 ,生根率可达 90 % ,平均根数 6 - 8条。本研究为喜树的遗传转化提供了前提。

Camptotheca acuminata, a deciduous tree, which grows in the southern China, contains an alkaloid of anti-cancer properties named camptothecin. In this article,the process of callus induction, organogenesis and plantlets regeneration of Camptotheca acuminata Decne was reported, and rapid propagation of stem segment and cotyledon node was also investigated. The cotyledons and hypocotyls of sterile seedling were cultured on NN69 medium added several hormone combination. All of these hormone combination were able to induce callus. The adventitious buts were obtained by organogenesis when callus were cultured on the NN69 medium supplemented with 6-BA (1.0 mg/L), IAA (0.05 mg/L), AS (afenine sulfate,10 mg/L). Each callus could produce about six well-differentiated buds. The differentiation rate reached 86%. These regenerative buds grew quickly and well in NN69 medium with the addition of BA (0.5 mg/L), KT (0.1 mg/L). The medium for the multiple buds induction of stem segment was NN69 with 6-BA (0.5 mg/L) and IAA (0.05 mg/L). The medium for multiple shoots induction of cotyledon node was NN69 added 6-BA (0.2 mg/L), IAA (0.05 mg/L) and AS (afinine sulfate, 10 mg/L). The medium for multiple buds proliferation was NN69 with 6-BA (0.25 mg/L) and IAA (0.05 mg/L). The medium for rooting was B5 medium with IBA (0.5 mg/L), KT (0.1 mg/L ) and AS (10 mg/L). Six to eight of roots per explants appeared and the rooting rate reached 90%. This result can be potentially used for genetic transformation of Camptotheca acuminata.