Nematology, 2010, Vol. 12(6), 915-928 Diversity and distribution of entomopathogenic nematodes in Chile Steve E DGINGTON 1,∗ , Alan G. BUDDIE 1 , Dave MOORE 1 , Andrés F RANCE 2 , Loreto MERINO 2 , Lukasz M. T YMO 1 and David J. HUNT 1 1 CABI, Bakeham Lane, Egham, Surrey, TW20 9TY, UK 2 Instituto de Investigaciones Agropecuarias (INIA), Avenida Vicente Méndez 515, Casilla 426, Chillán, Chile Received: 17 February 2010; revised: 1 March 2010 Accepted for publication: 1 March 2010 Summary – A systematic programme of surveys for entomopathogenic nematodes (EPN) was done in Chile between 2006 and 2008. The survey spanned the principal ecosystems of mainland Chile as well as a number of islands, and covered a wide range of habitats including the Atacama Desert, Andean Altiplano, temperate rainforests and subpolar territory. Nearly 1400 soil samples were collected, of which 7% were positive for EPN. Of 101 EPN isolates obtained, 94 were Steinernema spp. and seven were Heterorhabditis sp. Of the 94 Steinernema isolates, 39 were identified as Steinernema feltiae, the remainder being distributed between two new species, S. unicornum (52 records) and S. australe (three records). The Heterorhabditis isolates, all designated as Heterorhabditis sp.1, are referred to herein as H. cf. safricana. Steinernema feltiae and S. unicornum were collected predominately in the south of Chile and were obtained from a range of habitats, including forests, open grassland, montane soils and coastal zones; neither species was recovered from the far north of the country (viz., desert soils in the Norte Grande region). Steinernema australe was found in only three soil samples, all from humid, cool, coastal localities in the south. Heterorhabditis cf. safricana was recovered from the northern regions, with most isolates found in or on the periphery of the Atacama Desert; they were not recovered from cooler, more humid regions of southern Chile. Molecular information indicated there were two subgroups of both S. unicornum and S. feltiae, with a geographical, intraspecific split of subgroups between the most southerly and the more central survey zones. All isolates were collected by ex situ baiting with waxmoth larvae and the natural hosts are unknown. Keywords – desert, ecosystem, Heterorhabditis, Heterorhabditis cf. safricana, phylogeny, Steinernema, Steinernema australe, Steinernema feltiae, Steinernema unicornum. Interest in entomopathogenic nematodes (EPN) lies primarily in their potential as environmentally benign pest control agents, although the production of antimi- crobial compounds, particularly from bacterial symbionts (ffrench-Constant & Bowen, 1999), and aspects of co- evolution and speciation have also received attention (see Adams et al., 2006). This interest has spurred an array of EPN surveys from the equator to subpolar territories and, coupled with improved identification techniques (see Ho- minick et al., 1997; Hunt, 2007a), our knowledge of the diversity and distribution of this group of nematodes has increased considerably. However, the diversity and bio- geography of EPN in Chile have been largely unexplored. The first published record of an EPN native to Chile was recorded in 2009, when Steinernema australe was discov- ered on Isla Magdalena in the south of the country (Edg- ington et al., 2009a). Surveys in other South American ∗ Corresponding author, e-mail: s.edgington@cabi.org countries, including Brazil (Dolinski et al., 2008), Colom- bia (López-Núñez et al., 2007) and Argentina (Stock, 1995), have revealed numerous EPN species from a wide range of habitats. In Chile, a country with a tremendous variety of ecosys- tems and displaying many of the world’s climate types, there is reason to suggest a rich EPN fauna with a range of environmental adaptations. In Argentina, which shares a border with Chile for over 30 ◦ of latitude, relatively mod- est surveys have already revealed seven EPN species (in- cluding several new species) and numerous isolates from a variety of habitats characterised by soil type, vegetation cover, temperature and available insect hosts, etc. (Stock, 1995; de Doucet et al., 1999). This paper describes recent EPN surveys from some of the principal ecosystems in Chile. Scientists from the Instituto de Investigaciones Agropecuarias (INIA) and © Koninklijke Brill NV, Leiden, 2010 DOI:10.1163/138855410X498897 Also available online - www.brill.nl/nemy 915