赤霉素GA3调节黄芩组织培养中芽和根的形成

应用组织培养技术对黄芩进行外源激素调控研究。在培养不同时间进行的不同培养基之间的转移培养研究表明,组织培养条件下,在培养基中添加赤霉素,可显著刺激黄芩外植体芽的形成,同时抑制根的生长。在加有GA3的IAA培养基上,GA3显著影响黄芩组织培养物中的黄酮含量。在黑暗条件下,开始在2.5μmol/LIAA培养基中培养6d,随后转移到5μmol/LGA3培养基上培养,黄芩外植体中黄岑苷、黄岑素和汉黄芩苷的含量最高,分别为14.90,2.70和0.54μgmg-1(干重)。     

Thidiazuron-induced de novo shoot organogenesis on seedlings,etiolated hypocotyls and stem segments of Huang-qin

Development of an efficient in vitro propagation system for Huang-qin (Scutellaria baicalensis), a traditional Chinese medicinal plant used in the treatment of a wide range of human ailments, is described. Thidiazuron [TDZ: N-phenyl-N′- (1,2,3-thidiazol-5-ylurea)] effectively induced regeneration on cultured intact seedlings, etiolated hypocotyl explants and sterile stem segments of Huang-qin. Histological examinations of excised hypocotyl or nodal explants revealed that adventitious shoots formed through an intermediate callus. Comparison of TDZ-induced regeneration in the three tissue types indicated that isolation of explants was not essential for optimal regenerative efficiency. Significantly more regenerants formed along hypocotyls of intact seedlings (20 shoots/explant) than were observed on excised hypocotyls (9.7 shoots/explant) indicating that endogenous metabolites produced in adjacent tissues provided resources for the shoot initiation. More than 95% of de novo regenerants formed roots and then intact plantlets under either sterile culture or greenhouse conditions. Regeneration protocols developed in this study may provide the basis for improvement of this crop through the identification of medicinally active constituents and eventual development optimized pharmaceutical products. This revised version was published online in June 2006 with corrections to the Cover Date.