Page 51 - 《广西植物》2026年第7期
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7 期             李倚帆等: 马尾松不同分枝类型的顶芽内源激素、转录组与代谢组分析                                          1 1 4 7

             ( 1. College of Life Sciencesꎬ Guangxi Normal Universityꎬ Guilin 541006ꎬ Guangxiꎬ Chinaꎻ 2. Engineering Technology Research Center of Pinus
               massoniana of National Forestry and Grassland Administrationꎬ Engineering Technology Research Center of Pinus massoniana of Guangxiꎬ
                   Guangxi Key Laboratory of Superior Timber Trees Resource Cultivationꎬ Guangxi Forestry Research Instituteꎬ Nanning 530002ꎬ
                                Chinaꎻ 3. Guangxi National Qinlian Forest Farmꎬ Qinzhou 535000ꎬ Guangxiꎬ China )

                 Abstract: The improvement of traits including stem straightnessꎬ internode lengthꎬ and branching is an important
                 breeding objective for Pinus massonianaꎬ as branching directly affects stem form and timber yield. To explore the
                 mechanisms underlying the formation of different branching types in P. massonianaꎬ this study used fox ̄tail typeꎬ multi ̄
                 stem typeꎬ and normal branching type P. massoniana as materialsꎬ and analyzed the hormone contentsꎬ metabolomeꎬ and
                 transcriptome of apical buds. The results were as follows: (1) The contents of four key endogenous hormones — auxin
                 (IAA)ꎬ cytokinin (CTK)ꎬ abscisic acid (ABA)ꎬ and gibberellin (GA) — in the apical buds of the three branching
                 types differed significantlyꎬ following the order multi ̄stem type > normal branching type > fox ̄tail type. The ratios of
                 IAA/ ABA and IAA/ CTK were the highest in the fox ̄tail type and the lowest in the multi ̄stem type. Hormone ̄related
                 metabolites were predominantly enriched in pathways such as plant hormone signal transduction and zeatin biosynthesisꎬ
                 which are closely associated with the regulation of plant growth and branching development. (2) Kyoto encyclopedia of
                 genes and genomes ( KEGG) analysis of differentially expressed genes ( DEGs) revealed significant enrichment in
                 pathways including zeatin biosynthesisꎬ amino acid metabolismꎬ and pentose and glucuronate interconversion. Further
                 functional annotation and further screening identified 35 DEGs specifically associated with the plant hormone signal
                 transduction pathwayꎬ thereby highlighting the central role of transcriptional regulation in the formation of branching
                 traits in P. massoniana. (3) Integrated analysis indicated that cytokininsꎬ auxinsꎬ and their associated metabolites and
                 regulatory genes participated in the branching process of P. massonianaꎬ in which the compounds such as tryptamineꎬ
                 indoleꎬ and trans ̄zeatin showed an upregulated trend in the fox ̄tail typeꎬ while dihydrozeatin riboside showed an
                 upregulated trend in the multi ̄stem type. This study preliminarily elucidates the differential hormones and regulatory
                 mechanisms underlying branching variation in P. massonianaꎬ providing a reference for hormone ̄mediated branching
                 regulation in P. massoniana.
                 Key  words:  Pinus  massonianaꎬ  branchingꎬ  transcriptome  sequencingꎬ  differentially  expressed  genesꎬ
                 endogenous hormones



                植物分枝生长受到顶端优势的调控ꎬ这也是                            2008ꎻMauriat et al.ꎬ 2011)ꎮ 因此ꎬ植物激素的协
            决定植物形态的重要因素( 王瑞勤等ꎬ1994ꎻ刘婷                          同调控网络已经成为解析植物形态建成与植物分
            等ꎬ2022)ꎮ 分枝的生长和数量主要由顶芽和侧芽                          枝规律的主要研究方向之一ꎮ

            决定ꎬ影响植株的光合作用和形态建成( Zhang et                            马尾松(Pinus massoniana) 作为我国特有的用
            al.ꎬ 2014)ꎮ 在植物生长发育过程中ꎬ分枝受到遗                       材树种ꎬ因具有速生、适应性广、抗逆性强、用途广

            传、生物、环 境 等 多 种 因 素 的 共 同 调 控 ( Wang et             泛等特点ꎬ在造纸、建筑、松脂等林业产业中占据
            al.ꎬ 2018ꎻDong & Linꎬ2021)ꎬ其中植物激素及其                重要地位(杨章旗ꎬ2022)ꎮ 随着经济建设发展ꎬ林
            有关基因的调控协同发挥着主导作用ꎮ 生长素                              产品需求持续增长ꎬ对马尾松材性的要求也逐渐

            (auxinꎬIAA) 能 间 接 诱 导 腋 芽 休 眠 ( 胡 庆 毅 等ꎬ           提高(袁明等ꎬ2015):干形通直、轮枝间距长的马
            2022)ꎬ并参与细胞伸长、分裂等植物过程( 周玉滢                         尾松是大径材培育的核心目标( 杨章旗和舒文波ꎬ
            等ꎬ2024)ꎮ 高浓度生长素通过抑制细胞周期特异                          2012ꎻ杨章旗等ꎬ2018)ꎻ而特殊的多干马尾松可通
            蛋白的合成ꎬ与细胞分裂素( cytokininꎬCTK) 协同                    过增加主干数提高单位面积的产量( 张嵩ꎬ2021)ꎬ
            参与顶端优势的调控(胡晓等ꎬ2017)ꎬ细胞分裂素                          适合作为纸浆材的育种改良方向( 杨章旗ꎬ1994ꎻ
            直接促进侧芽萌发以调控分枝的数量ꎻ而降低赤                              陈虎等ꎬ2020)ꎮ 目前ꎬ在林业生产中普遍通过修
            霉 素 ( gibberellinsꎬ GA) 或 增 加 脱 落 酸 ( abscisic     枝的方式调控树形ꎬ这一过程不仅耗时ꎬ还需要投
            acidꎬABA) 的 含 量 均 能 促 使 腋 芽 萌 发 ( 张 焱 等ꎬ           入大量成本ꎮ
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