甘肃省4种苹果病毒检测及其分子多样性分析

Detection of Four Apple Viruses and Analysis of Its Molecular Diversity in Gansu Province

为明确甘肃省苹果产区苹果茎沟病毒(Apple stem grooving virus,ASGV)、苹果锈果类病毒(Apple scar skin viroid,ASSVd)、苹果褪绿叶斑病毒(Apple chlorotic leaf spot virus,ACLSV)和李属坏死环斑病毒(Prunus necrotic ringspot virus,PNRSV)4种病毒发生和分布情况,以及主要病毒的遗传多样性,采用RT-PCR技术进行鉴定,并对主要病毒cp基因片段测序分析。结果表明:在甘肃省5个市(县)苹果产区随机采集的93份叶片中,ASGV平均检出率达87.1%,ASGV成为危害甘肃省苹果的优势种,各苹果产区ASSVd、ACLSV和PNRSV平均检出率分别为41.9%、10.7%和11.8%,天水和兰州市4种苹果病毒检出率均高于其他地区;所有检测样品以“ASGV+ASSVd”为主要复合侵染类型,检出率达37.6%;4条ASGV cp基因片段的系统发育分析显示,4个分离物被聚在同一亚组,来自天水的分离物A29与来自中国云南苹果的ML-1分离物(JN871586.1)聚在同一支,与其核酸序列同源性为99.2%,A39与A42聚为一支,两者与来自中国陕西苹果的YL06分离物(EU236258.1)核酸序列同源性为97.1%和96.9%,A80与A39和A42共聚为一簇。

In order to clarify the occurrence and distribution of four apple viruses including apple stem grooving virus(ASGV),apple scar skin viroid(ASSVd),apple chlorotic leaf spot virus(ACLSV)and prunus necrotic ringspot virus(PNRSV),the species and its molecular diversity were detected and analyzed by RT-PCR and cp gene segments sequence.The results showed that the average detection rates of ASGV,ASSVd,ACLSV and PNRSV in 93 leaves of apple trees randomly collected from the apple-producing areas of 5 cities in Gansu province were 87.1%,41.9%,10.7%and 11.8%,respectively.The detection rates of four apple viruses were higher in Tianshui and Lanzhou than in other cities and ASGV was also considered as the dominant specie in Gansu province.The type of‘ASGV+ASSVd’was the main coinfection type among the tested samples and its detection rate was 37.6%.The four isolates were clustered in the same subgroup,and the A80,A39 and A42 isolates were clustered within the same cluster by the phylogenetic analysis of four ASGV cp gene segments;the A29 and ML-1(JN871586.1)isolates collected from Tianshui and Yunnan were clustered in the same branch,respectively,and the homology of nucleotide sequences between A29 and ML-1 was 99.2%;A39 and A42 isolates were clustered in one branch,and their homology of nucleotide sequences were 97.1%and 96.9%with the YL06(EU236258.1)isolate from Shaanxi.