28S Ribosomal DNA of Plant Infesting Mites: A Gene Applicable to Higher-level Acari Phylogeny

應用核醣體28S rDNA探討植食性蟎類高階親緣關係

華眞(Tsen Hua) ； 許凱文(Kivem Hsu) ； 李蕙宜(Hui-Yi Li) ； 張念台(Niann-Tai Chang) ； 葉文斌(Wen-Bin Yeh)

《台灣昆蟲》 27卷4期 (2007/12) Pp. 317-326

https://doi.org/10.6661/TESFE.2007025

摘要

核醣體28S rDNA序列已廣泛應用於節肢動物高階的親緣分析，但在蟎蜱的應用上卻仍罕見。本文分析9種葉蟎、2種擬葉蟎及2種根蟎28S rDNA 約3000個核苷酸的序列特性，並評估此基因在蟎蜱高階親緣關係的應用。28S rDNA序列在蟎蜱的變異並不是逢機的，其核心區段變異較其兩側的展延區小，且分類關係離越遠其序列差異就越大。散佈圖顯示，轉換取代與顛換取代有類似的線性變化；支序分析及群聚分析的親緣關係顯示，同科及同屬內的成員都群聚的很好，全爪蟎屬與小爪蟎屬的親緣關係近，與葉蟎屬較近的是岩蟎屬。28S rDNA的序列特性顯示，其核心序列適合分析較高階的蟎蜱親緣，而展延區則可應用於低階的分析。

關鍵字

葉蟎 ； 擬葉蟎 ； 根蟎 ； 28S rDNA

並列摘要

The nuclear 28S rDNA sequence has been widely used in higher phylogenetics of arthropod, but has seldom been applied to Acari. In this study, ~3000 bp of 28S rDNA sequences from nine tetranychids, two tenuipalpids and two acarid mites were used to probe the essence of this gene and its applicability to the delineation of phylogenetic relationship of these species. Sequences of 28S rDNA across Acari, though with variable region, were not randomly distributed, with the expansion segments being more variable than the core regions and with an increasing sequence divergence with taxonomic distances. Scatter plots of total substitutions (Tvs) against transversions (Tv) or transitions (Ts) in 28S region revealed similar and linear evolving processes for both Tv and Ts. Phylogenetic inferences from both parsimony and clustering methods suggest members of the same family and genus were grouped together; a close relationship between genera Panonychus and Oligonychus, and between genera Tetranychus and Petrobia. Analyses of the nearly complete sequences of Acari 28S rDNA have shown that its expansion region may be more useful in the resolution of lower taxonomic relationship, and its core region may be more reliable for that of higher category.

並列關鍵字

spider mite ； false spider mite ； bulb mite ； 28S rDNA