Turkish Journal of Agriculture and Forestry Turk J Agric For (2016) 40: 420-424 http://journals.tubitak.gov.tr/agriculture/ © TÜBİTAK Research Article doi:10.3906/tar-1507-42

Occurrence of a microsporidium in the predatory sycophanta L. (Coleoptera: Carabidae)

1, 2 3 Mustafa YAMAN *, Mahmut EROĞLU , Renate RADEK 1 Department of Biology, Faculty of Sciences, Karadeniz Technical University, Trabzon, Turkey 2 Department of Forest Engineering, Faculty of Forestry, Karadeniz Technical University, Trabzon, Turkey 3 Institute of Biology/Zoology, Free University of Berlin, Working Group Evolutionary Biology, Berlin, Germany

Received: 08.07.2015 Accepted/Published Online: 05.02.2016 Final Version: 18.05.2016

Abstract. Calosoma sycophanta L. (Coleoptera: Carabidae) is a voracious predatory beetle that feeds on several important lepidopteran pests. It is mass reared in laboratory breeding and released against forest pests. Any infection in this beetle is undesirable because it impacts production of effective and healthy . In the present study, a microsporidian pathogen was found in C. sycophanta. Mature spores of the pathogen are single, uninucleate, oval, and small, measuring about 3.04 × 1.7 µm. The spore wall is 100 to 110 nm thick and consists of two layers: an electron-dense outer layer, the exospore (30–35 nm), and an electron-lucent inner layer (the endospore; 70–80 nm). The polaroplast is of the lamellated type with thin lamellae anteriorly and thick lamellae posteriorly. A polar sac with an anchoring disc of the polar filament is clearly seen anteriorly. The polar filament is isofilar and has 8 coils, each 70 to 95 nm in diameter. The microsporidium presented here is the first pathogen recorded from this beetle and is tentatively classified as Microsporidium sp.

Key words: Microsporidia, forest caterpillar hunter, Calosoma sycophanta, disease

1. Introduction Central Asia up to Western Siberia (http://www.calosomas. Calosoma sycophanta L. (Coleoptera: Carabidae) is a com/Calosoma/cal_sycophanta.html). C. sycophanta is voracious predatory beetle that feeds on several important considered a very effective agent for biological control of lepidopteran pests. It was first released in 1905 in New several important lepidopteran pests, and it is produced England (Burgess, 1911). In the early 1900s, this beetle at great expense. Therefore, any infection by pathogenic was successfully introduced into the United States from organisms in C. sycophanta is undesirable. In the present Europe to control the gypsy moth (Howard and Fiske, study, we investigated the health of beetles in Turkish 1911; Burgess, 1915). C. sycophanta is an effective predator rearing laboratories and recorded a new microsporidium of the gypsy moth; adult beetles actively hunt gypsy moth infection in C. sycophanta samples. caterpillars, often climbing trees to capture their prey. It is estimated that one pair of C. sycophanta can consume 2. Materials and methods several hundred lepidopterous larvae (Ferrero, 1985). From thirteen rearing laboratories in Turkey, 955 dead and Because of these properties, the beetle has been tested living adult specimens of C. sycophanta were procured. To or used for the biological control of some important lepidopteran pests such as the gypsy moth (Lymantria find infected individuals, the beetles were dissected in dispar L.) (Ferrero, 1985; Weseloh, 1985, 1990; Weseloh Ringer’s solution and examined under a light microscope et al., 1995; Evans, 2009), the brown-tail moth (Euproctis at magnifications of 400–1000×. Microsporidian spores chrysorrhoea L.) (Evans, 2009), and the were measured, stained with Giemsa solution (after moths Thaumetopoea processionea L. (Ferrero, 1985) prefixation with methanol), and photographed using a and Thaumetopoea pityocampa (Den. & Schiff.) (and/ microscope equipped with a digital camera and software or Thaumetopoea wilkinsoni Tams) (Kanat and Özpolat, soft-imaging system. The ultrastructure of the pathogen 2006). was studied with a Zeiss EM 208 transmission electron C. sycophanta is found in Northern Africa and microscope using standard preparation techniques, as throughout Europe, Scandinavia, Asia Minor, Iran, and previously described (Yaman and Radek, 2003). * Correspondence: [email protected] 420 YAMAN et al. / Turk J Agric For

3. Results The microsporidium presented here is the first pathogen For the first time in Turkey, a microsporidian pathogen ever recorded from C. sycophanta. It was tentatively was found in C. sycophanta adults from four of thirteen classified as Microsporidium sp., since it is a distinct, yet sampled rearing laboratories: Demirci (Manisa), Selçuk undescribed, that cannot be identified on the (İzmir), Burhaniye (Balıkesir), and Antalya. In total, 19 of genus level because the merogonial and sporogonial stages the 955 examined beetles were infected by the pathogen. of the life cycle could not be studied. Further studies will The infection rate reached 20% in some laboratories. The be directed towards resolving the taxonomic status of the infection site was the hemolymph (blood cells) of the new microsporidian. host. Spores are oval and quite small (Figures 1,2), and Predator kill and feed on prey during their unfixed spores measured 3.04 ± 0.47 (2.08–3.98) µm (n = lifetimes. Healthy and effective predators are always 24) in length and 1.71 ± 0.22 (1.15–2.22) µm (n = 34) in desirable (Yaman et al., 2012). There is a trend towards width (Figure 1). Spores are monokaryotic (Figures 3–5). searching for pathogenic organisms in predator populations The spore wall is 100 to 110 nm thick and consists of two due to the potential for pathogen transmission from prey to layers: an electron-dense exospore (30–35 nm) and an predator or a natural infection in the predator. Yaman and electron-lucent endospore (70–80 nm). The polaroplast is Radek (2005) recorded the pathogenic alga Helicosporidium the lamellated type with thin lamellae anteriorly and thick sp. from the European bark beetle [Dendroctonus micans lamellae posteriorly (Figures 4, 6, and 7). A polar sac with (Coleoptera: Curculionidae)] and showed its transmission an anchoring disc of the polar filament was seen at the to Rhizophagus grandis (Coleoptera: Rhizophagidae), the anterior pole of the spore (Figures 4, 6, and 7). The polar specific predator of D. micans (Yaman and Radek, 2007). filament is isofilar, measures 70 to 95 nm in diameter, and The mode of transmission of Helicosporidium sp. differs has 8 coils (Figure 8). Unfortunately, we could not observe in detail from the transmission of microsporidia. One of the vegetative merogonial and sporogonial stages of the the reasons for Helicosporidium transmission from prey microsporidian due to the inclusion of dead hosts and to predator is that this pathogen has a very large host synchronic infection. The light and ultrastructural studies spectrum (Weiser, 1970; Kellen and Lindegren, 1973; showed that spores were not produced in sporophorous Sayre and Clark, 1978; Bläske and Boucias, 2004; Yaman vesicles (pansporoblasts); all mature spores were found as and Radek, 2005). Such transmission does not seem single cells. possible for the microsporidian presented here for several reasons. First, most microsporidia are known as host 4. Discussion specific, usually infecting only one or a few closely related The pathogen found in C. sycophanta is a microsporidian. host species. The host is the first taxonomic character in Spore ultrastructure confirms that the pathogen has microsporidia (Sprague et al., 1992). Second, the typical characteristics of microsporidia such as a the infected C. sycophanta samples studied here were polar filament with an anchoring disc, a polaroplast, a collected from rearing laboratories in which the beetles posterior vacuole, and a lack of mitochondria (Figures are only fed on larvae of the pathogen-free lepidopteran 3–8) (Larsson, 1986, 1999; Canning and Vavra, 2000). pest, T. pityocampa. To date, there has been no known

Figures 1 and 2. Light micrographs of the microsporidian pathogen infecting C. sycophanta. 1: Microsporidian spores including visible posterior vacuole in fresh smear. 2: Giemsa-stained spores marked by arrows. Bars = 5 µm.

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Figures 3–8. Transmission electron micrographs of microsporidian spores infecting C. sycophanta. 3–5: Longitudinal sections of monokaryotic spores; polaroplast (po), polar filament (pf), posterior vacuole (pv), exospore (ex), endospore (en), and nucleus (n). Note that monokaryon nuclei are visible. 6 and 7: Longitudinal sections of anterior of the spore; manubrium (ma), anchoring disc

(ps), thin lamellar type polaroplast (pp1), and thick lamellar type polaroplast (pp2). 8: Cross section of polar filaments; exospore (ex), endospore (en), and polar filament (pf). Bars = 1 µm for Figures 3 and 4 and 100 nm for Figures 5–8. microsporidian infecting this pest or its predator. Third, microsporidia infecting bark beetles, but none of them several species of beneficial insects that are collected could be found in its predator (Wegensteiner, 2004; Takov from fields or reared in insectaries for biological pest et al., 2010). We therefore conclude that C. sycophanta is control can be infected by microsporidia. Bjørnson and the original host for the Microsporidium sp. discovered. Oi (2014) updated the list of microsporidia naturally There are several studies showing that the beetle infecting predator insects. Unfortunately, the list does not C. sycophanta may be a useful natural control agent include all microsporidia that have been reported to infect against lepidopteran species (Weseloh et al., 1995; Kanat predator insects. Recently, Yaman et al. (2010) found a and Mol, 2008; Evans, 2009; Ceylan et al., 2012). When new microsporidian pathogen in R. grandis, an effective compared with chemical insecticides, predator insects predator of D. micans. Furthermore, there are several are effective alternative biological control agents that

422 YAMAN et al. / Turk J Agric For are safe for humans and other vertebrates. Currently insects under stress, as in mass-rearing laboratories, are this beetle is mass produced in 35 rearing laboratories more susceptible to microsporidian infections (Kluge and released for biological control of T. pityocampa and Caldwell, 1992). It is also possible, however, that in different regions of Turkey (Ceylan et al., 2012). A under stressful conditions latent infections in insects considerable amount of money has been spent for this may turn into acute, severe infections. Therefore, finding work. Therefore, it is always desirable to rear beetles a method for control of microsporidian pathogens in C. that are healthy and have high foraging proficiency sycophanta rearing laboratories is of great importance for and fecundity. However, microsporidia cause chronic the production of effective and healthy beetles. We suggest diseases in predators that are reared in laboratories for that all C. sycophanta rearing laboratories be monitored for biological control and reduce their foraging proficiency microsporidian pathogens in order to obtain noninfected and fecundity (Yaman et al., 2010; Bjørnson and Oi, 2014). colonies. Furthermore, microsporidia were shown to prolong larval and pupal development and reduce fecundity and Acknowledgment survival of adult predator beetles (Bjørnson and Keddie, The study was financially supported by the Scientific and 1999; Joudrey and Bjørnson, 2007; Bjørnson and Oi, Technological Research Council of Turkey (TÜBİTAK, 2014). Rearing laboratories cannot provide conditions research project; 114O722). identical to those in nature for the predatory beetles. Host

References

Bjørnson S, Keddie BA (1999). Effects of Microsporidium phytoseiuli Joudrey P, Bjørnson S (2007). Effects of an unidentified (Microsporidia) on the performance of the predatory mite, microsporidium on the convergent lady beetle, Hippodamia Phytoseiulus persimilis (Acari: Phytoseiidae). Biological convergens Guerin-Meneville (Coleoptera: Coccinellidae), Control 15: 153-161. used for biological control. J Inverteb Pathol 94: 140-143. Bjørnson S, Oi D (2014). Microsporidia biological control agents Kanat M, Mol T (2008). The effect of Calosoma sycophanta L. and pathogens of beneficial insects. In: Weiss LM, Becnel JJ, (Coleoptera: Carabidae) feeding on the pine processionary editors. Microsporidia: Pathogens of Opportunity. 1st edition, moth, Thaumetopoea pityocampa (Denis & Schiffermüller) Chichester, UK: Wiley, pp. 635-686. (Lepidoptera: Thaumetopoeidae) in the laboratory. Turk J Zool Bläske VU, Boucias DG (2004). Influence of Helicosporidium 32: 367-372. spp. (Chlorophyta: Trebouxiophyceae) infection on the Kanat M, Özpolat M (2006). Mass production and release of development and survival of three noctuid species. Environm Calosoma sycophanta L. (Coleoptera: Carabidae) used against Entomol 33: 54-61. the pine processionary moth, Thaumetopoea pityocampa Burgess AF (1911). Calosoma sycophanta: its life history, behavior (Schiff.) (Lepidoptera. Thaumetopoediae) in biological control. and successful colonization in New England. US Dept. Agric. Turk J Zool 30: 181-185. Bur. Entomol. Bull. 101. Kellen WR, Lindegren JE (1973). New host records for Burgess AF (1915). Report on the gypsy moth work in New England. Helicosporidium parasiticum. J Invertebr Pathol 22: 296-297. US Dept. Agric. Bull. 204. 32 p. Kluge RL, Caldwell PM (1992). Microsporidian diseases and Canning EU, Vavra J (2000). Phylum Microsporida. In: Lee JJ, biological weed control agents: to release or not to release? Leedale GF, Bradbury P, editors. The Illustrated Guide to the Biocont News Inform 13: 43N-47N. Protozoa. Lawrence, KS, USA: Allen Press Inc., pp. 39–126. Larsson JIR (1986). Ultrastructure, function, and classification of Ceylan S, Argun N, Cengiz N (2012). Avcı böcek Calosoma microsporidia. Progress in Protistology 1: 325-390. sycophanta (Coleoptera: Carabidae)’nın yetiştirilmesinde Spodoptera littoralis’in kullanım olanaklarının belirlenmesi. Larsson JIR (1999). Identification of microsporidia. Acta Protozool İç Anadolu Ormancılık Araştırma Enstitüsü Yayınları, Teknik 38: 161-197. Bülten, No: 294 (in Turkish). Sayre RM, Clark TB (1978). Daphnia magna (Cladocera: Evans VA (2009). The forest caterpillar hunter, Calosoma sycophanta. Chydoroidea): a new host of a Helicosporidium sp. (Protozoa: An old world species confirmed as part of the Virginia beetle Helicosporida). J Invertebr Pathol 31: 260-261. fauna (Coleoptera: Carabidae). Banisteria 34: 33-37. Sprague V, Becnel JJ, Hazard EI (1992). Taxonomy of phylum Ferrero F (1985). A precious forest auxiliary : Calosoma microspora. Crit Rev Microbiol 18: 285-395. sycophanta. Phytoma 370: 28. Takov D, Pilarska D, Wegensteiner R (2010). List of protozoan and Howard LO, Fiske WF (1911). The importation into the United States microsporidian pathogens of economically important bark of the parasites of the gypsy moth and brown tail moth. US beetle species (Coleoptera: Curculionidae: Scolytinae) in Dep. Agric. Bur. Entomol. Bull. 91. Europe. Acta Zoolog Bulg 62: 201-209.

423 YAMAN et al. / Turk J Agric For

Wegensteiner R (2004). Pathogens in bark beetles. In: Lieutier F, Yaman M, Radek R (2003). Nosema chaetocnemae sp. n., a Day KR, Battisti A, Grégoire JC, Evans HF, editors. Bark and microsporidian (Microspora: Nosematidae) parasite of Wood Boring Insects in Living Trees in Europe, Asynthesis. Chaetocnema tibialis (Chrysomelidae: Coleoptera). Acta Dordrecht, the Netherlands: Kluwer, pp. 291-313. Protozool 42: 231-237. Weiser J (1970). Helicosporidium parasiticum Keilin infection in the Yaman M, Radek R (2005). Helicosporidium infection of the caterpillar of a hepialid moth in Argentina. J. Protozool. 17: great European spruce bark beetle, Dendroctonus micans 436-440. (Coleoptera: Scolytidae). Europ J Protistol 41: 203-207. Weseloh R, Bernon G, Butler L, Fuester R, McCullough D, Stehr Yaman M, Radek R (2007). Infection of the predator beetle F (1995). Releases of Calosoma sycophanta (Coleoptera: Rhizophagus grandis Gyll. (Coleoptera, Rhizophagidae) with Carabidae) near the edge of gypsy moth (Lepidoptera: the insect pathogenic alga Helicosporidium sp. (Chlorophyta: Lymantriidae) distribution. Environ Entomol 24: 1713-1717. Trebouxiophyceae). Biological Control 41: 384-388. Weseloh RM (1985). Predation by Calosoma sycophanta L. Yaman M, Radek R, Linde A (2012). A new neogregarine pathogen (Coleoptera: Carabidae): evidence for a large impact on gypsy of Rhizophagus grandis. North-West J Zool 8: 353-357. moth, L. (Lepidoptera: Lymantriidae) pupae. Yaman M, Radek R, Weiser J, Aydın Ç (2010). A microsporidian The Canadian Entomologist 117: 1117-1126. pathogen of the predatory beetle Rhizophagus grandis Weseloh RM (1990). Experimental forest releases of Calosoma (Coleoptera: Rhizophagidae). Folia Parasitologica 57: 233-236. sycophanta (Coleoptera: Carabidae) against the gypsy moth. J Econ Entomol 83: 2229-2234.

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