Direct somatic embryogenesis and related gene expression networks in leaf explants of Hippeastrum ‘Bangkok Rose’  

作　　者：Jingjue Zeng Yi Deng Shahid Iqbal Jiarui Zhang Kunlin Wu Guohua Ma Lin Li Guangyi Dai Rufang Deng Lin Fang Songjun Zeng 

机构地区：[1]Guangdong Provincial Key Laboratory of Applied Botany,South China Botanical Garden,Chinese Academy of Sciences,Guangzhou,Guangdong 510650,China [2]University of the Chinese Academy of Sciences,Beijing 100049,China [3]South China National Botanical Garden,Guangzhou,Guangdong 510650,China [4]Zhaoqing Branch Center of Guangdong Laboratory for Lingnan Modern Agricultural Science and Technology,Zhaoqing,Guangdong 526000,China [5]Horticultural Science Department,North Florida Research and Education Center,University of Florida/IFAS,Quincy,FL 32351,USA [6]Public Laboratory of South China Botanical Garden,Chinese Academy of Sciences,Guangzhou,Guangdong 510650,China [7]Key Laboratory of South China Agricultural Plant Molecular Analysis and Gene Improvement,South China Botanical Garden,Chinese Academy of Sciences,Guangzhou,Guangdong 510650,China

出　　处：《Horticultural Plant Journal》2024年第2期556-572,共17页园艺学报（英文版）

基　　金：funded by Guangdong Basic and Applied Basic Research Foundation (Grant No.2023A1515010237);the 2021 Dongguan Provincial Rural Revitalization Program (Grant No.20211800400022);the Guangdong Key Technology Research and Development Program (Grant Nos.2020B020220005,2022B1111040003);the Guangdong Modern Agricultural Industry Technology System Program (Grant No.2023KJ121);the South China Botanical Garden,the Chinese Academy of Sciences (Grant No.QNXM-02)。

摘　　要：Hippeastrum, a highly diverse genus in the Amaryllidaceae family, is a valuable ornamental bulbous flowering plant. Somatic embryogenesis(SE) is an efficient method for mass production of Hippeastrum plantlets. Previous studies have been devoted to the in vitro propagation of Hippeastrum, but the SE and its regulatory networks are rarely reported. In this study, we established a direct SE method of Hippeastrum Bangkok Rose' using leaf bases as explants. MS supplemented with 1.00 mg·L^(-1)NAA +1.00 mg·L^(-1)KT + 0.25 mg·L^(-1)TDZ was the optimal medium for SE. Histological observations showed that the bipolar somatic embryo originated from the epidermal cell layer and underwent initiation,globular, scutellar and coleoptile stages. During SE, endogenous hormones of IAA, CTK, ABA, and SA were highly accumulated. Transcriptomic analysis revealed the genes encoding auxin biosynthesis/metabolic enzymes and efflux carriers were induced, while the auxin receptor of TIR1 and ARF transcriptional repressor of Aux/IAA were down-regulated and up-regulated, respectively, leading to suppression of auxin signaling. In contrast, cytokine signaling was promoted at the early stage of SE, as biosynthesis, transport, and signaling components were up-regulated.Various stress-related genes were up-regulated at the early or late stages of SE. Chromatin remodeling could also be dynamically regulated via distinct expression enzymes that control histone methylation and acetylation during SE. Moreover, key SE regulators, including WOXs and SERKs were highly expressed along with SE. Overall, the present study provides insights into the SE regulatory mechanisms of the Hippeastrum.

关 键 词：Hippeastrum Tissue culture Somatic embryogenesis Gene regulation 

分 类 号：S682.25[农业科学—观赏园艺]