Hua Tsen, Chantawannakul Panuwan, Tsai Cheng-Lung, Yeh Wen-Bin
Department of Entomology, National Chung Hsing University, Taichung 402, Taiwan. E-mail:
Department of Plant Medicine, National Pingtung University of Science and Technology, Pingtung 912, Taiwan.
Zool Stud. 2023 Mar 31;62:e11. doi: 10.6620/ZS.2023.62-11. eCollection 2023.
The Modern beekeeping industry is being challenged by the varroan mite and its transmitted pathogens. Various types of exhibit different levels of virulence toward honey bees, but only the Japanese (J) and Russian (R) types were found to infect . Type R was more highly virulent against in comparison with type J. Examining the genetic profile of Varroa species is therefore of crucial importance in apiary management. In this study, maternally inherited mitochondrial cytochrome oxidase I () and bisexual nuclear internal transcribed spacer (ITS) sequences of individuals from Taiwan were determined. All 168 sequences observed in populations obtained from were identical and belonged to type J, with one base difference to that of populations collected from ; the new type is named 'T type' (Taiwan type). ITS sequences of and its sister species were identical. A network analysis based on 611 sequences compiled from references indicated the presence of 27 haplotypes in . Epidemic history and relationship analyses of showed that the basal haplotypes were those from and many R-extending haplotypes infesting involving amino acid substitutions. Calibration dating based on analysis revealed that differentiated from its sibling lineage (occurring in Sri Lanka) prior to 1.3 million years ago (Mya). The ancestral haplotype retention and drift in that occurred locally during 0.10-0.64 Mya might be relevant to its host , which had been isolated geologically. The highly virulent type R was spreading quickly and could gradually outcompete the common and less virulent type J. Type T, being intermediate between types R and J, ought to be studied to better understand the pathogenic mechanism of in . Moreover, for areas where type R does not occur, such as Taiwan, quarantine requirements are crucial for reducing invasion risks.
现代养蜂业正受到瓦螨及其传播病原体的挑战。不同类型的瓦螨对蜜蜂表现出不同程度的毒力，但仅发现日本（J）型和俄罗斯（R）型会感染蜜蜂。与J型相比，R型对蜜蜂的毒力更强。因此，检测瓦螨种类的基因图谱在养蜂管理中至关重要。在本研究中，测定了来自台湾的瓦螨个体的母系遗传线粒体细胞色素氧化酶I（COI）和两性核内转录间隔区（ITS）序列。从台湾采集的种群中观察到的所有168条COI序列均相同，属于J型，与从中国大陆采集的种群有一个碱基差异；这种新类型被命名为“T型”（台湾型）。瓦螨及其姊妹种的ITS序列相同。基于参考文献汇编的611条COI序列进行的网络分析表明，瓦螨存在27种单倍型。瓦螨的流行历史和关系分析表明，基础单倍型来自中国大陆，许多侵染蜜蜂的R扩展单倍型涉及氨基酸替换。基于COI分析的校准年代测定显示，瓦螨在130万年前（Mya）之前就与其姊妹谱系（出现在斯里兰卡）分化。在0.10 - 0.64 Mya期间在当地发生的瓦螨祖先单倍型保留和漂移可能与其宿主蜜蜂有关，蜜蜂在地理上一直处于隔离状态。高毒力的R型正在迅速传播，并可能逐渐胜过常见且毒力较弱的J型。T型介于R型和J型之间，应该进行研究以更好地了解瓦螨在蜜蜂中的致病机制。此外，对于R型未出现的地区，如台湾，检疫要求对于降低入侵风险至关重要。
