Platycladus orientalis ‘Beverleyensis’ is an important ornamental tree species. Plant endogenous hormones（i.e.， indole-3-acetic acid（IAA）， zeatin（ZT）， abscisic acid（ABA） and jasmonic（JA）） play an important role in regulating the adventitious roots regeneration process， but the dynamic changes of endogenous hormones at different developmental stages and their effects on adventitious roots are still unclear. Using semi-woody branches as materials， the dynamic changes of four endogenous hormones were detected by high performance liquid chromatography- mass spectrum（LC-MS）. The results showed that the root primordium originated from callus， medullary ray， xylem， vascular cambium， secondary phloem， cortex， and the junction of medullary ray and cambium respectively， which belonged to multiple locus occurrence mode and the multiple rooting type. Hormonal dynamics results showed that the content of IAA and ZT decreased， ABA and JA increased with the formation of callus； the content of IAA and ZT increased slowly， ABA and JA decreased with the differentiation of root primordium； IAA， ZT， JA gradually increased， and ABA maintained at a low level during adventitious root formation and elongation. Hormone balance analysis results showed that the IAA/ABA ratio and IAA/JA ratio both decreased， and the increasing of IAA/ZT ratio was beneficial to the formation of callus， and on the contrary， it was beneficial to the induction and differentiation of root primordia， while the IAA/ABA ratio increased， IAA/ZT and IAA/ JA maintained at a low level was conducive to the formation and elongation of adventitious roots. The results provide a basis for revealing the regulation effect of different endogenous hormones on the development of adventitious roots of P. orientalis ‘Beverleyensis’.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2022.02.013