Biological control of Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae) using Metarhizium anisopliae JEF-003 millet grain Se Jin Lee, Sihyeon Kim, Jeong Seon Yu, Jong Cheol Kim, Yu-Shin Nai ⁎, Jae Su Kim ⁎ Department of Agricultural Biology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju 561-756, Republic of Korea abstract article info Article history: Received 31 October 2014 Revised 22 December 2014 Accepted 9 February 2015 Available online 17 February 2015 Keywords: Entomopathogenic fungi Aedes albopictus Metarhizium anisopliae Transformant Granular formulation Mosquitoes have been becoming serious vectors worldwide thus effective and safe control strategies should be established. Entomopathogenic fungi can be alternative controlling agents by substituting chemical insecticides. Herein we assayed 12 soil-borne entomopathogenic fungi against Asian tiger mosquito (Aedes albopictus) larvae in laboratory conditions and tried to establish an effective application method using millet granular formulation (GR). Twelve fungal isolates which belong to 6 genera (Beauveria, Cordyceps, Metarhizium, Paecilomyces, Purpureocillium and Verticillium) were assayed; M. anisopliae JEF-003 showed the fastest mosquitocidal activity, approximately 73% mortality rate at 2 days post-inoculation (dpi.) and N 90% mortality rate at 5 dpi. Conidia of M. anisopliae JEF-003 also showed a dosage dependent activity at 1 × 10 5 , 1 × 10 6 and 1 × 10 7 conidia ml -1 . Hy- phal growth of M. anisopliae JEF-003 in the Ae. albopictus larvae was observed by infection of an M. anisopliae JEF- 003 EGFP-transformant, which was generated by restriction enzyme-mediated integration (REMI) method. GR of M. anisopliae JEF-003 showed high virulence to Ae. albopictus larvae (N 90% mortality) after 5 days of application. These results suggest that M. anisopliae JEF-003 has a potential to control A. albopictus larvae and GR can be prac- tically used for management of the serious vector in water environment. © 2015 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society. Published by Elsevier B.V. All rights reserved. Introduction Mosquitos (Culicidae) are vectors which carry several serious human diseases from person to person without having the symptoms them- selves. Transmission of mosquito-borne diseases may be accelerated by global climate change. Various mosquito species can transmit different diseases, such as malaria (transmitted by the genus Anopheles) and lym- phatic filariasis (primarily transmitted by Anopheles spp., Aedes spp., and Culex spp.) (Rozendaal, 1997; Verma and Prakash, 2010). Most of mosquito-borne viral diseases are transmitted by Aedes spp., such as yellow fever, dengue, dengue hemorrhagic fever (Rozendaal, 1997), and chikungunya fever (Powers et al., 2000). Aedes spp. are distributed worldwide. In tropical countries, Ae. aegypti is an important vector of yellow fever, dengue fever, and Chikungunya fever (Rozendaal, 1997; Hochedez et al., 2006); Ae. albopictus is a closely related species that also can transmit viral diseases, such as several types of encephalitis (Savage et al., 1994; Gerhardt et al., 2001), and is known to transmit even several filarial nematodes such as Dirofilaria immitis (Cancrini et al., 2003). Ae. albopictus has become an epidemiolog- ically important vector. To control Aedes vectors, several insecticides have been employed as larvicides that are applied to mosquito breeding sites or adulticides applied to mosquito adults; modes of application include insecticide residual sprays (IRS), space sprayings, treated/impregnated materials (Vontas et al., 2012), and thermal fogging. Mosquitocides are diverse and include organophosphates (e.g. temephos), insect growth reg- ulators (e.g. pyriproxyfen), pyrethroids (Kroeger et al., 2006; World Health Organization, 2011), and bacterial toxins (e.g. Bacillus thuringiensis serovar israelensis) among others. Although insecticide- based interventions have efficiently controlled Aedes mosquito popula- tions, it has been reported that Ae. aegypti shows resistance to all four classes of insecticides (carbamates, organochlorines, organophos- phates, and pyrethroids) (Ponlawat et al., 2005; Ranson et al., 2010). Due to the negative effect of insecticides on ecosystems and substan- tial increase in physiological resistance shown by mosquitoes (Hargreaves et al., 2000), biological control agents which can reduce the drawbacks associated with insecticides (Krischbam, 1985) should be considered. The use of entomopathogenic fungi can be an alternative control method, and some efforts have already been conducted. Fungal patho- gens such as Lagenidium, Coelomomyces, and Culicinomyces are known to affect mosquito populations, and have been studied extensively. However, many other fungi infect and kill mosquitoes at the larval and/or adult stage (Scholte et al., 2004), such as Metarhizium anisopliae isolates, Beauveria tenella, and Lagenidium giganteum (Balaramn et al., Journal of Asia-Pacific Entomology 18 (2015) 217–221 ⁎ Corresponding authors at: Department of Agricultural Biology, College of Agriculture and Life Sciences, Chonbuk National University, Republic of Korea. Tel.: +82 63 270 2525; fax: +82 63 270 2531. E-mail addresses: d95632003@gmail.com (Y.-S. Nai), jskim10@jbnu.ac.kr (J.S. Kim). http://dx.doi.org/10.1016/j.aspen.2015.02.003 1226-8615/© 2015 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society. Published by Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Journal of Asia-Pacific Entomology journal homepage: www.elsevier.com/locate/jape