Auxin regulation and MdPIN expression during adventitious root initiation in apple cuttings  

作　　者：Ling Guan Yingjun Li Kaihui Huang Zong-Ming(Max)Cheng 

机构地区：[1]College of Horticulture,Nanjing Agricultural University,210095 Nanjing,China [2]Institute of Pomology,Jiangsu Academy of Agricultural Sciences,Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement,210014 Nanjing,China [3]Department of Plant Sciences,University of Tennessee,Knoxville,TN 37831,USA

出　　处：《Horticulture Research》2020年第1期955-966,共12页园艺研究（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant no.31601738).

摘　　要：Adventitious root(AR)formation is critical for the efficient propagation of elite horticultural and forestry crops.Despite decades of research,the cellular processes and molecular mechanisms underlying AR induction in woody plants remain obscure.We examined the details of AR formation in apple(Malus domestica)M.9 rootstock,the most widely used dwarf rootstock for intensive production,and investigated the role of polar auxin transport in postembryonic organogenesis.AR formation begins with a series of founder cell divisions and elongation of the interfascicular cambium adjacent to vascular tissues.This process is associated with a relatively high indole acetic acid(IAA)content and hydrolysis of starch grains.Exogenous auxin treatment promoted this cell division,as well as the proliferation and reorganization of the endoplasmic reticulum and Golgi membrane.In contrast,treatment with the auxin transport inhibitor N-1-naphthylphthalamic acid(NPA)inhibited cell division in the basal region of the cuttings and resulted in abnormal cell divisions during the early stage of AR formation.In addition,PIN-FORMED(PIN)transcripts were differentially expressed throughout the whole AR development process.We also detected upregulation of MdPIN8 and MdPIN10 during induction;upregulation of MdPIN4,MdPIN5,and MdPIN8 during extension;and upregulation of all MdPINs during AR initiation.This research provides an improved understanding of the cellular and molecular underpinnings of the AR process in woody plants.

关 键 词：HYDROLYSIS ELITE DWARF 

分 类 号：S661.1[农业科学—果树学]