我国部分苹果产区苹果锈果类病毒的检测和全序列分析

Detection and full nucleotide sequences analysis of Apple scar skin viroid isolates in some apple producing areas of China

近年来,由苹果锈果类病毒Apple scar skin viroid(ASSVd)引起的苹果花脸病、锈果病在我国一些苹果产区日趋严重,对我国苹果生产和苹果产业发展造成严重危害。为了解ASSVd在我国一些苹果产区的发生和变异情况,采用RT-PCR对陕西、山东、山西、河北、北京和黑龙江6个苹果产区的35份苹果样品进行检测,并克隆获得30个分离物的基因组全序列,大小为330~333个核苷酸。分析表明,这些分离物的基因组全序列与GenBank中ASSVd基因组核苷酸序列相似度为96%~100%,在苹果锈果类病毒属的末端保守区及中央保守区保守,在致病区和左端区域有突变,一些分离物的突变位点相同。系统发育分析表明分离物因相同的突变位点而聚类,而与地理来源无关。

In recent years,dappling,scarring and malformation on apple fruits caused by Apple scar skin viroid(ASSVd)is increasing and seriously affects apple production and apple industry development in China.To understand the occurrence and variations of ASSVd in apple production regions of China,35 samples were collected from six major apple producing areas including Shaanxi,Shandong,Shanxi,Hebei,Beijing and Heilongjiang provinces.Reverse transcription-PCR and sequence analysis showed that 30 isolates of ASSVd were obtained with genome sizes of 330-333 nucleotides,which had 96%-100% identities with sequences of ASSVd in GenBank,and had conserved terminal conserved region(TCR)and central conserved region(CCR).Mutations were found in pathogenic region and terminal left region.Interestingly,same mutation sites were found in some isolates.Phylogenetic analysis showed that these isolates clustered due to mutation sites on ASSVd genome while no relation to geographical origins.