金塔柏扦插不定根形成与内源激素的调控研究  

Regulation Mechanism of Endogenous Hormones in Adventitious Roots Formation of Platycladus orientalis‘Beverleyensis’

作　　者：刘国彬 廖婷 王烨 郭丽琴 赵今哲 姚砚武 曹均 Liu Guobin;Liao Ting;Wang Ye;Guo Liqin;Zhao Jinzhe;Yao Yanwu;Cao Jun(Beijing Academy of Forestry and Pomology Sciences,Beijing 100093)

机构地区：[1]北京市林业果树科学研究院,北京100093

出　　处：《植物研究》2022年第2期278-288,共11页Bulletin of Botanical Research

基　　金：北京市农林科学院青年科研基金(QNJJ202112,QNJJ201923);北京市农林科学院科技创新能力建设专项(KJCX20200207,KJCX20200114,KJCX20200402);北京市林业果树科学研究院青年科研基金(LGYJJ202004);国家林木种质资源共享服务平台(2005DKA21003)。

摘　　要：金塔柏(Platycladus orientalis‘Beverleyensis’)是重要的观赏树种。生长素(IAA)、玉米素(ZT)、脱落酸(ABA)和茉莉酸(JA)在金塔柏扦插不定根再生过程中起着重要的调控作用,但不同发育阶段内源激素的动态变化及其对不定根发生的影响仍不清楚。以金塔柏半木质化枝条为材料,采用连续组织切片技术观察了不定根发生过程,利用高效液相色谱串联质谱法检测了4种内源激素含量的动态变化。结果表明,金塔柏不定根原基起源于愈伤组织、髓射线、木质部、维管形成层、次生韧皮部、皮层、髓射线与形成层交界处等部位,属于多位点发生模式和多类型生根方式。在不定根形成过程中,随着愈伤组织的形成,IAA和ZT含量下降,ABA和JA含量升高;随着根原基的分化,IAA和ZT含量缓慢升高,ABA和JA含量下降;随着不定根形成与伸长,IAA、ZT、JA逐渐升高,ABA维持在低水平。激素平衡分析发现,IAA/ABA比值和IAA/JA比值下降、IAA/ZT比值上升利于愈伤组织的形成,反之利于根原基的诱导分化,而IAA/ABA比值升高,IAA/ZT和IAA/JA维持在较低水平利于不定根形成与伸长。研究结果为揭示不同内源激素对金塔柏扦插不定根再生的调节作用提供了依据。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’.

关 键 词：金塔柏 不定根 内源激素 根原基 动态平衡 

分 类 号：Q944.54[生物学—植物学] Q945.45