两种砧木楸树嫁接苗生长差异及转录组比较分析  

Growth Differences Among Grafted Seedlings with Two Rootstocks of Catalpa bungei and Comparative Analysis of Transcriptome

作　　者：付钰 贾瑞瑞 何荷 王良桂[1] 杨秀莲[1] FU Yu;JIA Rui-rui;HE He;WANG Liang-gui;YANG Xiu-lian(College of Landscape Architecture,Nanjing Forestry University,Nanjing 210037)

机构地区：[1]南京林业大学风景园林学院,南京210037

出　　处：《生物技术通报》2023年第8期251-261,共11页Biotechnology Bulletin

基　　金：江苏省农业科技自主创新资金项目(CX(19)2038)。

摘　　要：嫁接是楸树(Catalpa bungei)良种扩繁的主要途径。为探讨以梓树和滇楸为砧木的两种‘苏楸1号’良种当年生嫁接苗生长差异,比较了二者的嫁接成活率、新梢长度、新梢粗度、接穗粗度/砧木粗度、叶面积等,以筛选较佳砧木,并通过高通量测序平台对两种嫁接苗叶片和顶芽进行转录组测序分析,采用实时荧光定量PCR技术对初步筛选的差异表达基因进行验证。结果显示,以梓树为砧木的嫁接成活率和嫁接苗各生长量均显著高于以滇楸为砧木的嫁接苗;转录组测序筛选出两个组合叶片和顶芽差异表达基因共计559个,其中上调表达基因192个,下调表达基因367个;GO富集分析表明559个差异表达基因显著富集在代谢过程、细胞过程、细胞器、结合和催化活性等功能类别;KEGG富集分析表明叶片中213个差异表达基因显著富集到66条代谢途径,顶芽中137个差异表达基因显著富集到45条代谢途径;初步筛选出的Unigene0040270、Unigene0006320、Unigene0036149和Unigene0007805等4个差异表达基因的RT-qPCR趋势与转录组数据一致。本研究结果发现两种嫁接苗的生长存在显著差异,其中以梓树为砧木的嫁接苗各生长参数更好,同时在转录组角度上对其差异进行了初步解析,为楸树嫁接分子研究提供一定的参考价值。Grafting is the main way of reproducing and expanding Catalpa bunge of superior cultivar.In order to investigate the growth differences of two‘Suqiu No.1’superior cultivars,taking Catalpa ovata and Catalpa fargesii as rootstocks,the survival rate,new shoot length,new shoot thickness,scion diameter/stock diameter,leaf area of the two cultivars were studied for screening the better rootstock.Transcriptome sequencing was performed on the leaves and terminal buds of the two grafted seedlings by high-throughput sequencing platform.The differentially expressed genes were confirmed by quantitative real-time PCR.The results showed that the survival rate and the growth of the grafted seedlings with C.ovata as the rootstock were significantly higher than those with C.fargesii as the rootstock.Total 559 differentially expressed genes were screened by transcriptome sequencing,including total 192 up-regulated genes and total 367 down-regulated genes.GO enrichment analysis showed that total 559 differentially expressed genes were significantly enriched in metabolic process,cellular process,organelles,binding and catalytic activities;KEGG enrichment analysis showed that total 213 differentially expressed genes were significantly enriched to total 66 metabolic pathways in leaves,and total 137 differentially expressed genes were significantly enriched to total 45 metabolic pathways in terminal buds.The RT-qPCR trends of four differentially expressed genes(Unigene0040270,Unigene0006320,Unigene0036149 and Unigene0007805)were consistent with the transcriptome data.The results of this study showed that there were significant differences in the growth of the two grafted seedlings,among which the growth parameters of the grafted seedlings with C.fargesii as the rootstock were better.At the same time,the differences were preliminarily analyzed from the perspective of transcriptome,providing a certain reference value for the study of C.bungei grafting molecules.

关 键 词：嫁接 楸树 生长差异 转录组 差异表达基因 

分 类 号：S792.99[农业科学—林木遗传育种]