新疆苹果树上苹果锈果类病毒(ASSVd)的检测与全序列分析

Identification and sequence analysis of the Apple scar skin viroid isolated from apple trees in Xinjiang Province

【目的】检测并分析新疆223团场多年生苹果树上的苹果锈果类病毒。【方法】对采自新疆库尔勒223团的多年生苹果树的枝条、叶片、果实((果皮、种子))样品进行RNA提取,利用RT-PCR技术检测鉴定。【结果】(1)多年生的‘金冠’苹果树上检测到苹果锈果类病毒,得到4条克隆序列(ASSVd Y1:KC110858;ASSVd Y6:KC110859;ASSVd Y8:KC110860;ASSVd Y10:KC110861),所得序列与Gen Bank中已报道的国内外ASSVd序列同源性达85%以上。(2)序列比对可知,4条‘金冠’分离物序列之间只有3个碱基变异,与首次登录生物X17696有26个碱基变异,其中有4个碱基缺失和5个碱基插入,且变异多集中在类病毒序列的TL与TR区。【结论】通过序列分析比对,各寄主上的ASSVd分离物核酸序列变异较小,建立了优化的RT-PCR检测方法,为苹果树ASSVd的快速检测奠定了良好的基础。

【Objective and Method】The samples used for low molecular weight RNAs extraction were tender leaves,shoots and fruits of perennial apple trees collected from 223 tuanchang in Xinjiang province.We detected ASSVd（ Apple scar skin viroid） in perennial apple trees by reverse transcription-polymerase chain reaction（ RT-PCR）,and then analyzed the sequence of ASSVd.【Result】（ 1） The results showed that Golden delicious apple trees were infected with ASSVd and the sequences of four isolates（ Accession numbers KC110858 ~ KC110861） had over 85% identity with previously published sequences in Gen Bank.（ 2） Sequence alignment results indicated that only three bases varied between the sequences of four isolates,26 bases varied between the sequences of four isolates and logined gene（ X17696）,contained four bases insertion and five bases deletion,and the variations were concentrated upon TL and TR regions of viroid sequence.【Conclusion】This study showed that ASSVd isolates from different host plant had no geographic and variety.We established optimized detection methods of RT-PCR successfully and thus provided the basis for the rapid identification of ASSVd in fruit trees.