松材线虫对长白落叶松的致病性  

Pathogenicity of Bursaphelenchus xylophilus to Larix olgensis Seedlings

作　　者：曹业凡 汪来发[1] 王曦茁[1] 范结红 Cao Yefan;Wang Laifa;Wang Xizhuo;Fan Jiehong(Key Laboratory of Forest Protection of National Forestry and Grassland AdministrationResearch Institute of Forest Ecology,Environment and Protection,Chinese Academy of Forestry,Beijing 100091;Forestry Bureau of Wangjiang County,Anhui Province Wangjiang 246200)

机构地区：[1]中国林业科学研究院森林生态环境与保护研究所国家林业和草原局森林保护学重点实验室,北京100091 [2]安徽省望江县林业局,望江246200

出　　处：《林业科学》2020年第11期108-115,共8页Scientia Silvae Sinicae

基　　金：中国林业科学研究院基本科研业务费专项(CAFYBB2018SZ006):国家重点研发专项(2016YFC1201200);国家重点研发专项(2017YFD0600103-1-4)。

摘　　要：【目的】研究松材线虫对长白落叶松的致病性,致病过程中的迁移运动和超氧化物歧化酶SOD的活性变化,为松材线虫对长白落叶松的致病机制研究及长白落叶松的松材线虫病害防控提供理论依据。【方法】以2年生盆栽长白落叶松幼苗为研究对象,人工接种辽宁清原株系(QH-1)、江苏南京株系(NM-1)与重庆株系(CM-1)松材线虫,每株接种2000条,分别于接种1、2、4、7、10、15与25天后在落叶松幼苗接种点上下进行等距(1.5 cm)茎段截取与茎段横截面病害观察,计数不同截取茎段线虫,统计分析不同株系松材线虫在落叶松幼苗内的移动能力,同时接种后1-7天分别对接种幼苗叶片取样,用于SOD活性变化分析。接种35天后统计接种幼苗发病率与再分离线虫数量,结合不同株系松材线虫的移动能力与接种幼苗SOD活性变化,分析不同株系松材线虫对长白落叶松幼苗的致病性。【结果】QH-1、NM-1与CM-1均能导致2年生长白落叶松幼苗萎蔫,但接种QH-1的幼苗首次发病时间比NM-1和CM-1早5天。接种35天后,QH-1、NM-1和CM-1接种的长白落叶松幼苗的发病率分别为100%、70%和60%,感病指数分别为100、43.3与40。接种QH-1、NM-1和CM-1后的萎蔫幼苗中均可分离到松材线虫,平均每株线虫量分别为(23457±2862)条、(14090±2190)条与(15857±2079)条,差异显著(P<0.01)。QH-1、NM-1和CM-1接种长白落叶松后移动能力存在明显差异,其中QH-1移动能力强于NM-1与CM-1。QH-1、NM-1和CM-1接种长白落叶松幼苗后SOD活性变化趋势存在明显差异,其中QH-1处理组SOD活性上升幅度与下降幅度大于NM-1和CM-1处理组。横截面观察结果表明,在长白落叶松幼苗在接种QH-1、NM-1和CM-1后,QH-1对长白落叶松的破坏程度最重。【结论】辽宁清原、江苏南京与重庆株系松材线虫对2年生长白落叶松幼苗均具有致病性,其中辽宁清原株系松材线虫对长白落叶松幼苗致病性最�【Objective】This study aims to provide theoretical basis on pathogenicity mechanism of Larix olgensis with pine wilt disease,and give some advice on pine wilt disease control in northern China.To this end,we investigated the pathogenicity and migration of pinewood nematode(PWN)Bursaphelenchus xylophilus in L.olgensis and the activity changes of superoxide(SOD)in L.olgensis after being inoculated with PWNs.【Method】Two-year-old L.olgensis seedlings were inoculated sepa rately with three different isolates of PWN(QH-1,NM-1,and CM-1),the number of inoculation was 2000 nematodes per seedling.After then,the pathogenicity,the external symptom and the nematode migration were observed daily.The stems segments with the same length above and below the inoculation spot(1.5 cm)were cut down in 1,2,4,7,10,15,and 25days after the inoculation,the cross-section was observed for detecting the disease occurrence and the migration of PWNs.Leaves were collected every day till 7days after inoculation,to analysis the change of SOD activity in L.olgensis.In 35 days after the inoculation,the morbidity was recorded and PWNs were extracted separately from wilt seedlings.The pathogenicity and migration of QH-1,NM-1,and CM-1 PWN in L.olgensis seedlings and the change of SOD activity in L.olgensis were analyzed.【Result】L.olgensis seedlings were all wilt after inoculation with QH-1,NM-1 and CM-1 PWNs,but QH-1 PWNs caused seedlings to wilt 5days earlier than NM-1 and CM-1 PWNs.In 35 days after the inoculation,the morbidity rates of seedlings inoculated with QH-1,NM-1,and CM-1 PWN were 100%,70%and 60%,respectively,and the disease-infected indices were 100,43.3 and 40,respectively.The number of PWNs of QH-1 treatment was significantly greater than that of NM-1 and CM-1 treatments(P<0.01).The migration ability of PWNs after inoculation showed the difference among QH-1,NM-1,and CM-1,and the migration ability of QH-1 was higher than that of NM-1,and CM-1.The change of SOD activity in L.olgensis showed the difference over QH-1,NM-1,and CM-

关 键 词：松材线虫 长白落叶松 致病性 人工接种 发病率 

分 类 号：S763.11[农业科学—森林保护学]