Eur. J. Entomol. 106: 405–413, 2009 http://www.eje.cz/scripts/viewabstract.php?abstract=1468 ISSN 1210-5759 (print), 1802-8829 (online) Identification and biological traits of a planthopper from the genus Pentastiridius (Hemiptera: Cixiidae) adapted to an annual cropping rotation ALBERTO BRESSAN1*, WERNER E. HOLZINGER2, BENOIT NUSILLARD3, OLIVIER SÉMÉTEY1, FRÉDÉRIC GATINEAU1, 4, MAURO SIMONATO5 and ELISABETH BOUDON-PADIEU1 1Biologie et écologie des bactéries du phloème, UMR Plante Microbe Environnement INRA, CNRS, Université de Bourgogne, BP 86510, 21065 Dijon Cedex, France 2Oekoteam – Institute for Animal Ecology and Landscape Planning, Bergmanngasse 22, 8010 Graz, Austria 3Interactions gestion forestière et biodiversité, CEMAGREF, Domaine des Barres, 45290 Nogent-sur-Vernisson, France 4CIRAD, TA 80/A, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France 5Università di Padova, Dipartimento di Agronomia Ambientale e Produzioni Vegetali, Viale dell’Università 16, 35020 Legnaro, Italy Key words. Insect vector, Hemiptera, Fulgoromorpha, Pentastiridius leporinus, Pentastiridius beieri, syndrome basses richesses, stolbur phytoplasma, phloem-restricted bacteria Abstract. Cixiid planthoppers have been shown to vector phloem-limited prokaryotes associated with plant diseases world-wide. In eastern France, an emerging disease of sugar beet called syndrome “basses richesses” has been associated with phloem-restricted bacteria transmitted by a cixiid planthopper within the genus Pentastiridius. Early investigation suggested the species being Pen- tastiridius beieri. On the basis of a morphological and phylogenetic study we report the identification of the planthopper as Pentasti- ridius leporinus. Furthermore we report some biological traits of the species, which shows a surprising ecological adaptation to an annual cropping rotation sugar beet-winter cereals. INTRODUCTION this paper) to sugar beet (Gatineau et al., 2001, 2002). The disease has been termed syndrome “basses richesses” The family Cixiidae Spinola, 1839 (Hemiptera: Ful- for the reduced sugar content in infected beet tap roots goromorpha) includes about 160 genera comprising (Richard-Molard et al., 1995). Previous research has almost 2000 phytophagous planthopper species distrib- shown that SBR bacterium is the most important uted world-wide (Holzinger et al., 2002; Ceotto & Bour- pathogen causing syndrome “basses richesses” disease, goin, 2008). Generally, cixiid planthoppers spend a sig- while stolbur phytoplasma has a marginal etiological role nificant part of their life cycle underground as immature (Sémétey et al., 2007a). Pentastiridius sp. has consis- stadia feeding on host plant roots; whereas adults feed tently shown to be the major vector of SBR bacterium as and reproduce on the aerial parts of their host plants. In populations can reach very high densities in sugar beet temperate regions, most of cixiid planthoppers have been fields (Gatineau, 2002; Sémétey, 2006; Bressan et al., reported as univoltine, overwintering as nymphal stages 2008) with high rates of SBR bacterium infection underground. However, detailed information on their (Sémétey et al., 2007a; Bressan et al., 2008). ecology and biology is restricted to a few pests such as The planthopper species was tentatively identified as Hylalesthes obsoletus Signoret (Leclant, 1968; Sforza et Pentastiridius beieri Wagner, 1970 (Gatineau, 2002). al., 1999; Sharon et al., 2005; Johannesen et al., 2008) However, further morphological examination rejected this that transmits stolbur phytoplasma to a number of culti- identification (unpubl.), and we have referred to this spe- vated plant species (Fos et al., 1992; Maixner, 1994; cies as Pentastiridius sp. (Gatineau et al., 2001, 2002; Sforza, 1998). However the emergence and re-emergence Sémétey et al., 2007a, b). On the basis of recent investi- of vector-transmitted diseases associated with plant gations we have assigned and used the name Pentasti- pathogenic prokaryotes have recently promoted investiga- ridius leporinus (Linnaeus, 1761) for the cixiid plan- tion on these fulgoroids that include an increasing number thopper spreading SBR bacterium in eastern France of potential vector species (Gatineau et al., 2001, 2002; (Arneodo et al., 2008; Bressan et al., 2008; Bressan, in Bogoutdinov, 2003; Danet et al., 2003; Jovic et al., 2007). press; Bressan et al., in press). However, demonstration In eastern France, an unidentified cixiid planthopper for this taxonomic assignment has not yet been published. within the genus Pentastiridius has been shown to To date, three Pentastiridius species of the subgenus transmit both a stolbur phytoplasma and a phloem- Pentastiridius s. str. are known from Europe: P. beieri, P. restricted J-3 proteobacterium (called SBR bacterium in leporinus and P. spinicoronatus Dlabola, 1988 (Emel- * Corresponding and present address: Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, Honolulu, HI 96822, USA; e-mail: [email protected] 405 TABLE 1. Collection sites, host plants, and accession numbers of cytocrome oxidase gene I and II sequences from cixiid planthop- pers examined. Planthopper species Collection site, region (Country) Host plant Sequence accession numbers Hyalesthes obsoletus Roncá, Veneto (Italy) Urtica dioica FN179291 1Pentastiridius leporinus Russia Unknown FN179288 Pentastiridius beieri Valbelle, Upper Savoy (France) Salix sp. FN179290 Pentastiridius sp. Fenay, Burgundy (France) Beta vulgaris FN179289 Reptalus cuspidatus Roncá, Veneto (Italy) Artemisia vulgaris FN179292 1Kindly provided by D.Z. Bogoutdinov. janov, 1995). Pentastiridius leporinus was described from at the museum of Natural History (Paris, France) under refer- Sweden and is distributed throughout Europe, near East, ence numbers: MNHN(EH)-3573 through MNHN(EH)-3632. Middle and East Asia, and Northern Africa (Anufriev & Additional P. leporinus and P. bei males from the collections of Emeljanov, 1988). Pentastiridius beieri was described by the Natural History museums in Vienna and Linz (Austria), and from the Oekoteam collection (Graz) were studied morphologi- Wagner (1970) from Italy and Austria. Further records cally. These specimens originated from Marismas near Santona, originate from France, Germany, Poland, Slovenia, Swit- Santander (Spain), Holstein, Oldesloe (Germany), zerland and Ukraine (Günthart, 1987; Holzinger & Seljak Feldkirch/Vorarlberg (Austria), Rödschitzer Moor near Mittern- 2001; Holzinger et al., 2003; Nast, 1977; Nickel et al., dorf (Austria), Gutenstein (Austria), Grado (Italy), Skyros 2002; Nickel, 2003; Remane & Fröhlich, 1994). Pentasti- (Greece), Sari-Tzelek (Kirghizia). ridius beieri is distinguishable from P. leporinus only by Male genitalia were isolated from individual males after the shape of the aedeagus (Wagner, 1970; Holzinger et immersion and dissection of the anal segment in 10% KOH al., 2003). Pentastiridius leporinus has been recorded to solution for about 10 h at room temperature. Male genitalia feed mainly on Phragmites australis (Nickel, 2003; Holz- were used for morphological identification by comparison with inger et al., 2003; Anufriev & Emeljanov, 1988) while P. taxonomic keys available for the genus Pentastiridius (Wagner, 1970; Dlabola, 1988; Holzinger et al., 2003). Drawings of male beieri feeds on various shrubs and tall herbs (Salix, Alnus, genitalia from specimens of Pentastiridius sp. were made by Myricaria, Tripleurospermum) (Wagner, 1970; Holzinger using a stereoscopic microscope (Nikon SMZ-U) and a bin- et al., 2003). The third species, P. spinicoronatus is ocular (Wild and Olympus SZH10) with a camera lucida. known from Italy (Emilia province) only. According to For phylogenetic analysis, in addition to specimens of Pen- Dlabola (1988), the shape of the male gonostyles is tastiridius sp. collected from Burgundy and Franche-Comté unique in the genus Pentastiridius. Dlabola’s (l.c.) draw- regions, we included specimens of H. obsoletus, P. beieri, P. ings indicate similarities on the shape of the aedeagus leporinus, and Reptalus cuspidatus (Fieber 1876). Sites for between P. spinicoronatus and P. beieri, but they showed insect collection, and host plants are reported in Table 1. To clear differences with P. leporinus. reconstruct the phylogeny of these specimens, we sequenced cytochrome oxidase subunits I and II (COI and COII). For DNA In this work we analyzed the morphology of genitalia isolation insects were individually processed with a cethyltri- from Pentastiridus sp., the major vector of bacteria asso- methyl ammonium bromide (CTAB) procedure according to ciated with syndrome “basses richesses” disease Gatineau et al. (2001). For each species considered, we obtained (Gatineau et al., 2001, 2002; Sémétey et al., 2007a, b). independent sequences from three individual insects. Because literature has reported detailed studies only on To obtain sequences from COI and COII, we first amplified in male genitalia of planthoppers within the genus Pentasti- PCR assays a fragment of about 800 bp from gene COI with ridius, here we have exclusively studied male genitalia. primer pair C1J 2183-TL2N 3014 (Simon et al., 2006). A longer Furthermore, based on mitochondrial DNA sequences, we fragment that included a portion of COI, a tRNA for leucine, have conducted a phylogenetic analysis to examine the and a portion of about 550 bp from gene COII was obtained with PCR amplification with primer pair C1J 2441-C2N 3661 evolutionary relationship of Pentastiridus