我国12个地区草莓叶螨种类分子鉴定及遗传多样性

为明确草莓上的叶螨种类及其遗传多样性,以便准确有效地指导草莓叶螨防治。本研究选取我国12个代表性的地区,采集草莓上的叶螨。采样范围覆盖了我国华北、华中、华东和西南的草莓产区。扩增和测定线粒体cox1基因部分序列,将所获得的序列通过BLAST与GenBank数据库中的序列进行比对,确定叶螨种类,并对cox1基因序列的多样性进行分析。测序获得了长度为632bp的cox1基因片段。BLAST比对结果和系统发育分析表明,来自我国12个地区的91个样品均为二斑叶螨Tetranychus urticae。遗传多样性分析发现我国草莓上二斑叶螨的cox1基因有2种单倍型,其中11个地区仅存在1种单倍型,北京昌平检测到2种单倍型。两种单倍型之间有1个核苷酸的同义突变。本研究表明,二斑叶螨为这些地区草莓上唯一的叶螨种类,种群内遗传多样性非常低。研究结果对于制定草莓上叶螨的防治策略具有指导意义。

Molecular identification and genetic diversity of spider mites on strawberry from 12 regions of China

To identity the species of spider mites on strawberry for accurate and effective control measures, spider mites on strawberry were collected from 12 representative regions covering major strawberry production areas in Northern, Central, Eastern and Southwestern China. The mitochondrial cox1 gene sequence was amplified and sequenced for each individual. The sequences were compared with the database of GenBank using BLAST algorithm to determine the species of spider mite. The diversity of cox1 gene sequences was analyzed. The amplified length of cox1 gene segment was 632 bp. Molecular identification indicated that all of 91 samples from 12 regions of China were the two-spotted spider mite Tetranychus urticae. Genetic diversity analysis revealed that there were two haplotypes in the cox1 gene of T. urticae. Only one haplotype was observed in 11 sites, and two haplotypes were detected in Changping, Beijing. Synonymous mutation of one nucleotide was observed between the two haplotypes. The results revealed that T. urticae is the dominant spider mite on strawberry in China with low genetic diversity in all populations. The results of this study will provide guidance for the development of control strategies on strawberry spider mites.