Parasites of vectors - <it>Ixodiphagus hookeri </it>and its <it>Wolbachia </it>symbionts in ticks in the Netherlands

• Main Authors: Tijsse-Klasen Ellen, Braks Marieta, Scholte Ernst-Jan, Sprong Hein
• Format: Article
• Language: English
• Published: BMC 2011-12-01
• Series: Parasites & Vectors
• Subjects: Ixodiphagus hookeri; Ixodes ricinus; Parasitic wasp; Tick; <it>Wolbachia</it>
• Online Access: http://www.parasitesandvectors.com/content/4/1/228

<p>Abstract</p> <p>Background</p> <p><it>Ixodiphagus hookeri </it>is a parasitic wasp of ixodid ticks around the world. It has been studied as a potential bio-control agent for several tick species. We suspected that the presence of <it>Wolbachia </it>infected <it>I. hookeri </it>eggs in ticks is responsible for incidental detection of <it>Wolbachia </it>DNA in tick samples.</p> <p>Methods</p> <p>The 28S <it>rRNA </it>and 16S <it>rRNA </it>genes of a specimen of <it>I. hookeri </it>was amplified and sequenced. PCR on part of the 28S <it>rRNA </it>gene was used to detect parasitic wasp DNA in 349 questing <it>Ixodes ricinus </it>ticks from various sampling sites. Furthermore, the <it>wsp </it>gene of <it>Wolbachia </it>was sequenced from the <it>I. hookeri </it>specimen and a subset of ticks was tested using this marker.</p> <p>Results</p> <p>Several sequences from tick specimens were identical to the <it>Wolbachia </it>sequence of the <it>I. hookeri </it>specimen. <it>Ixodiphagus hookeri </it>was detected in 9.5% of all tested ticks, varying between 4% and 26% depending on geographic location. Ten out of eleven sampling sites throughout the Netherlands were positive for <it>I. hookeri</it>. Eighty-seven percent of <it>I. hookeri-</it>positive but only 1.6% of <it>I. hookeri</it>-negative ticks were <it>Wolbachia </it>positive. Detection of <it>I. hookeri </it>DNA was strongly associated with the detection of <it>Wolbachia </it>in ticks.</p> <p>Conclusion</p> <p>This is the first reported case of <it>I. hookeri </it>in the Netherlands. Furthermore <it>I. hookeri </it>harbours <it>Wolbachia </it>species and is broadly distributed in the Netherlands. While detection of <it>Wolbachia </it>DNA in ticks might often be due to parasitism with this wasp, other sources of <it>Wolbachia </it>DNA in ticks might exist as well.</p>