梨火疫病菌在库尔勒香梨枝条中的侵染定殖和扩展特征研究.pdf
《梨火疫病菌在库尔勒香梨枝条中的侵染定殖和扩展特征研究.pdf》由会员分享,可在线阅读,更多相关《梨火疫病菌在库尔勒香梨枝条中的侵染定殖和扩展特征研究.pdf(11页珍藏版)》请在咨信网上搜索。
1、果树学报2023,40(8):1692-1702Journal of Fruit ScienceDOI:10.13925/ki.gsxb.20230056梨火疫病菌在库尔勒香梨枝条中的侵染定殖和扩展特征研究吕天宇1#,徐琳赟1#,席海珅1,韩剑1,2,罗明1,2*(1新疆农业大学农学院 农林有害生物检测与防控重点实验室,乌鲁木齐 830052;2农业农村部西北荒漠绿洲农林外来入侵生物防控重点实验室,乌鲁木齐 830052)摘要:【目的】示踪梨火疫病菌Erwinia amylovora在库尔勒香梨(Pyrus sinkiangensis Yu)(简称香梨)枝条组织中侵染定殖和扩展特征,为梨火疫病
2、的有效防治提供依据。【方法】以分离获得梨火疫病强致病力菌株E.a001为材料,采用热激法将携带有绿色荧光蛋白基因(green fluorescent protein,GFP)质粒phc60-gfp转化E.a001,获得了能发出强烈绿色荧光的标记菌株E.a001-gfp。利用该标记菌株接种香梨枝条,检测、观察其在香梨枝条组织中的侵染定殖和扩展动态。【结果】针刺接种和喷雾接种E.a001-gfp引起枝条发病的最低浓度分别为106cfumL-1和107cfumL-1。相同浓度的病原菌接种,喷雾接种较针刺接种后发病显症时间延迟23 d。梨火疫病菌侵染枝条产生的坏死病斑的扩展速率随病原菌浓度提高而升高;
3、病菌在1年生枝条上的生长扩展速度显著快于在2年生枝条内的扩展速度。梨火疫病菌入侵后主要存在于枝条维管系统中,大量分布于皮层薄壁细胞和韧皮部薄壁细胞间隙,少量存在于木质部导管中。在香梨发病枝条上,病健交界处的活菌数量最高,可达到108cfug-1,未显症部位010 cm处病原菌为105cfug-1,但在香梨枝条病斑外未显症部位1015 cm处均未分离出病原菌。【结论】研究明确了梨火疫病菌在香梨枝条组织中的扩展距离、迁移时间及速率,以及分布及定殖量,为病枝的准确修剪和制定病害的综合防控措施提供了科学依据。关键词:库尔勒香梨;梨火疫病菌;绿色荧光蛋白基因标记;侵染;扩展中图分类号:S661.2S43
4、6.612文献标志码:A文章编号:1009-9980(2023)08-1692-11收稿日期:2023-02-22接受日期:2023-04-27基金项目:新疆维吾尔自治区自然科学基金重点项目(2021D01D12);国家重点研发计划(2021YFD1400200);新疆维吾尔自治区重大科技专项(2019A01001-2)作者简介:吕天宇,在读硕士研究生,研究方向为植物细菌性病害。E-mail:。#为共同第一作者。*通信作者Author for correspondence.E-mail:Characterization of the infectious colonization and ex
5、pansion with GFPtagged strain of Erwinia amylovora in Kuerlexiangli pear(Pyrus sinkian-gensis Yu)shootsL Tianyu1#,XU Linyun1#,XI Haishen1,HAN Jian1,2,LUO Ming1,2*(1College of Agriculture,Xinjiang Agricultural University/Key Laboratory of Detection and Prevention and Control of Agricultural andForest
6、ry Pests,Urumqi 830052,Xinjiang,China;2Key Laboratory of Prevention and Control of Invasive Organisms in Northwest DesertOasis Agriculture and Forestry,Ministry of Agriculture and Rural Affairs,Urumqi 830052,Xinjiang,China)Abstract:【Objective】Fire blight is a major international quarantine bacterial
7、 disease caused by Erwin-ia amylovora,a destructive bacterium that infests pears,apples and other kinds of rosaceae nut fruittrees.In 2016 and 2017,it was found for the first time in Yili and Bazhou in Xinjiang,China,harmingpear,apple,hawthorn,begonia,quince and other fruit trees,especially spreadin
8、g extremely fast on Kuer-lexiangli pear(Pyrus sinkiangensis Yu),resulting in severe economic loss to the pear industry.The infes-tation characteristic that E.amylovora can transfer rapidly in the host tissues is an important reason forthe fast epidemic speed,destructive damage and great difficulty o
9、f control.Timely pruning of diseasedfruit trees can not only greatly reduce the amount of pathogenic bacteria,but also prevent its migrationand expansion in the tree,which is an important measure for disease prevention and control and easy to,等:和扩展特征研究第8期梨火疫病是由解淀粉欧文氏菌Erwinia amylovo-ra侵染梨、苹果等多种蔷薇科仁果
10、类果树、造成毁灭性危害的重大国际检疫性细菌病害1-2。该病害于1780年首次报道于美国纽约,现分布于北美、欧洲、北implement and cost-effective.The artificial inoculation of tracing pathogenic bacteria in pear branch tis-sue infestation colonization and migration characteristics was employed to deeply understand the patho-genic bacteria in the host tissue
11、infestation expansion process and mechanism in order to guide the fieldpruning of diseased branches,disease resistant varieties selection and breeding and the development ofintegrated control measures【Methods】In this study,the virulent pathogenic strain E.a001 was isolatedthe shoots infested by fire
12、 blight,and the Green Fluorescent Protein(GFP)plasmid phc60-gfp was trans-formed into E.a001 by thermal excitation method,and the strong green fluorescent strain E.a001-gfpwas successfully obtained.The inoculations of different concentrations of E.a001-gfp suspension wereconducted with two methods,n
13、eedle prick and spray,to detect and observe the dynamics of infestationand expansion in the tissues of pear shoots.【Results】The GFP-labeled E.a001-gfp strain emittedstrong green fluorescence under fluorescence microscopy,and a target fragment of about 700 bp wasamplified from the genomic DNA of the
14、labeled bacteria.The morphology,growth curve and pathoge-nicity of the tagged strain E.a001-gfp were not significantly different from those of the wild type,andits green fluorescence was stably inherited.The lowest concentrations of E.a001-gfp for inducing shootdisease were 106cfumL-1and 107cfumL-1f
15、or needle inoculation and spray inoculation,respectively.The expansion rate of the necrotic spots produced by the pathogen-infested shoots increased with theconcentration of the pathogen,and the expansion rate of spots on shoots treated with 109cfumL-1inocu-lation was the fastest,and the migration r
16、ate was up to 3.96 cmd-1.The migration time of the necroticspots produced by the E.a001-gfp inoculation in the pear shoots was 12-15 d(average 13.5 d).The ex-pansion distance of spots in 1-year-old branches was 37.72-47.27 cm(average 42.77 cm),and in 2-year-old branches was 2.05-3.86 cm(mean 3.21 cm
17、)respectively,which were significantly different.The re-sults of spray inoculation treatment were similar to those of the needle prick method.The laser confocalscanning microscope observation showed that the pathogenic bacteria mainly presented in the branchvascular system after invasion,and a large
18、 number of them were distributed in the cortical thin-walledcells and the interstices of the bast thin-walled cells,and a small number of them distributed in the xy-lem ducts.The E.a001-gfp was colonized at the necrotic lesions,disease-healthy junction and 0-10 cmof the non-significant part of the b
19、ranch,and it could still be isolated at 40 d.The highest number of via-ble bacteria was found at the disease-healthy junction,which could reach 108cfu g-1tissue,and thehighest number of pathogenic bacteria was 105cfug-1tissue at 0-10 cm of the undeveloped part of thebranch,but no pathogenic bacteria
20、 were isolated at 10-15 cm of the undeveloped part of the pearbranch outside the diseased spot.It is suggested that pruning the diseased branch at 20-30 cm of the vis-ible spot of the fire blight susceptible pear branch could effectively remove the pathogen,which is asafe and effective pruning lengt
21、h;the pathogenic bacteria could survive in the diseased branches for along period of time,and the viable bacteria count of fire blight bacteria detected in the diseased branch-es stored at room temperature for 6 months was 105cfug-1.【Conclusion】The study clarified the expan-sion distance,migration t
22、ime and rate,distribution and colonization amount of the E.amylovora,in thebranch tissue of pear,which provided a scientific basis for the accurate pruning of diseased branchesand the formulation of comprehensive prevention and control measures of the disease.Key words:Kuerlexiangli pear(Pyrus sinki
23、angensis Yu);Erwinia amylovora;Green fluorescent pro-tein(GFP)genetagged;Infestation;Extension吕天宇,等:梨火疫病菌在库尔勒香梨枝条中的侵染定殖和扩展特征研究1693果树学报第40卷非、中东和大洋洲等近60多个国家和地区3。近年来梨火疫病又传播至亚洲的日本、哈萨克斯坦、吉尔吉斯斯坦等国,20162017年相继在中国新疆伊犁、巴州等地首次被发现,危害梨、苹果、山楂、海棠、温桲等果树,尤其在库尔勒香梨(简称香梨)上传播极为迅速,造成大批梨树被砍伐、果园被毁的巨大损失,给香梨生产带来重创。该病害近期已传播至
24、甘肃张掖等地区,目前在中国尚属局部发生,现已被中国列入 一类农作物病虫害名录 和 重点管理外来入侵物种名录,对中国林果安全生产带来了巨大威胁和风险4-5。国外针对梨火疫病的病原学、检测技术和预测预警、流行规律和防治技术等开展了大量研究,提出了包括化学防治、生物防治、抗病品种选育、转基因技术和果园苗圃的综合治理等多种防控措施。但目前果树抗病品种匮乏,专门的防治药剂有限,也没有能高效控制病害的单一措施,至今病害依然是威胁梨和苹果产业的突出问题6。已有研究表明,梨火疫病菌E.amylovora在寄主组织中快速转移的侵染特征是造成病害流行速度快、毁灭性危害和防治难度大的重要原因。梨火疫病菌通过伤口和自
25、然孔口侵入寄主多个部位,造成花器、叶片、幼果变黑凋萎、新梢枯死。易感寄主在气候条件适宜时,病原菌从病梢快速扩展到枝条、树干,直至砧木和根部,严重时可在几周或1至几个生长季导致全株枯死;病原菌在感病果树枝干的溃疡斑、枝条及病果,以及不表现症状的组织上越冬,还可在木质部导管中存活多年,难以根除。春季病原菌在病灶处大量繁殖作为当年的初侵染源,通过风雨、昆虫、鸟类及田间操作将病原菌传至寄主上造成初次侵染和再次侵染7-8。因此及时修剪发病果树的病枝,不仅可以大大降低病原菌的菌源量,还能阻止其在树体中的迁移扩展,是简便易行、经济有效的病害防控的重要措施。明确梨火疫病菌在不同寄主组织内生长及扩展特性,对深入
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 疫病 库尔勒 枝条 中的 侵染 扩展 特征 研究
1、咨信平台为文档C2C交易模式,即用户上传的文档直接被用户下载,收益归上传人(含作者)所有;本站仅是提供信息存储空间和展示预览,仅对用户上传内容的表现方式做保护处理,对上载内容不做任何修改或编辑。所展示的作品文档包括内容和图片全部来源于网络用户和作者上传投稿,我们不确定上传用户享有完全著作权,根据《信息网络传播权保护条例》,如果侵犯了您的版权、权益或隐私,请联系我们,核实后会尽快下架及时删除,并可随时和客服了解处理情况,尊重保护知识产权我们共同努力。
2、文档的总页数、文档格式和文档大小以系统显示为准(内容中显示的页数不一定正确),网站客服只以系统显示的页数、文件格式、文档大小作为仲裁依据,平台无法对文档的真实性、完整性、权威性、准确性、专业性及其观点立场做任何保证或承诺,下载前须认真查看,确认无误后再购买,务必慎重购买;若有违法违纪将进行移交司法处理,若涉侵权平台将进行基本处罚并下架。
3、本站所有内容均由用户上传,付费前请自行鉴别,如您付费,意味着您已接受本站规则且自行承担风险,本站不进行额外附加服务,虚拟产品一经售出概不退款(未进行购买下载可退充值款),文档一经付费(服务费)、不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
4、如你看到网页展示的文档有www.zixin.com.cn水印,是因预览和防盗链等技术需要对页面进行转换压缩成图而已,我们并不对上传的文档进行任何编辑或修改,文档下载后都不会有水印标识(原文档上传前个别存留的除外),下载后原文更清晰;试题试卷类文档,如果标题没有明确说明有答案则都视为没有答案,请知晓;PPT和DOC文档可被视为“模板”,允许上传人保留章节、目录结构的情况下删减部份的内容;PDF文档不管是原文档转换或图片扫描而得,本站不作要求视为允许,下载前自行私信或留言给上传者【自信****多点】。
5、本文档所展示的图片、画像、字体、音乐的版权可能需版权方额外授权,请谨慎使用;网站提供的党政主题相关内容(国旗、国徽、党徽--等)目的在于配合国家政策宣传,仅限个人学习分享使用,禁止用于任何广告和商用目的。
6、文档遇到问题,请及时私信或留言给本站上传会员【自信****多点】,需本站解决可联系【 微信客服】、【 QQ客服】,若有其他问题请点击或扫码反馈【 服务填表】;文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“【 版权申诉】”(推荐),意见反馈和侵权处理邮箱:1219186828@qq.com;也可以拔打客服电话:4008-655-100;投诉/维权电话:4009-655-100。