为了探究植物生长调节剂多效唑(PP333)调控药用植物美洲商陆(Phytolacca americana)毛状根生长和次生代谢的可能性, 设计实验并探讨PP333对美洲商陆毛状根生长及其商陆皂苷甲含量的影响。结果表明, 与对照相比, PP333使毛状根根尖及侧根表面呈浅红色, 侧根变得短而粗, 且随着培养基内PP333浓度的升高, 根表面颜色加深。培养基中添加0.5-5.0 mg·L^-1 PP333能促进毛状根中商陆皂苷甲的产生, 其中以1.0 mg·L^-1 PP333的效果最好, 其商陆皂苷甲含量达6.22 mg·g^-1 DW, 约为对照的1.94倍。PP333能提高毛状根苯丙氨酸裂解酶(PAL)的活性, 并可能通过对PAL酶活性的调节来促进毛状根中商陆皂苷甲的产生。

To explore the possibility of the use of the plant growth regulator paclobutrazol (PP333) to regulate growth and secondary metabolism of hairy roots, we examined the effect of PP333 on the growth and production of esculentoside A in Phytolacca americana hairy roots. Compared to the control, with increasing concentration of PP333 in the medium, the lateral roots of hairy roots became short and thick and the root tips and surface of lateral roots turned light red and the root surface became redder. The addition of 0.5-5.0 mg∙L^-1 PP333 in the medium promoted the production of esculentoside A in hairy roots. The highest content of esculentoside A, 6.22 mg∙g^-1 dry weight, about 1.94 times that of the control, was obtained with 1.0 mg∙L^-1 PP333. The enhanced production of esculentoside A by PP333 may be related to its regulation of phenylalanine ammonia lyase activities of P. americana hairy roots.