ecological engineering 34 ( 2 0 0 8 ) 328–331 available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/ecoleng Comparison of biological and conventional insecticide treatments for the management of the pineapple fruit borer, Strymon megarus (Lepidoptera: Lycaenidae) in Costa Rica Diego J. Inclán a , Felipe J. Bermúdez a , Edgar Alvarado a , Mike Ellis b , Roger N. Williams b,* , Nuris Acosta b a EARTH University, P.O. Box 4442-1000, San José, Costa Rica b The Ohio State University, OARDC, 1680 Madison Avenue, Wooster, OH 44691, United States article info Article history: Received 20 May 2008 Received in revised form 2 July 2008 Accepted 3 July 2008 Keywords: Pineapple Thecla Fruit borer Strymon megarus Natural insecticides Carbaryl Economics abstract Carbaryl is currently one of the most commonly used insecticides for the control of the pineapple fruit borer, Strymon megarus (Godart), in commercial pineapple production. To evaluate more sustainable biological alternatives to conventional insecticides, three micro- bial and one botanical insecticide were studied. Beauveria bassiana, Metarhizium anisopliae, Bacillus thuringiensis (Bt) and a plant extract from Quassia amara were compared with car- baryl in replicated field trials in Costa Rica during 2005 and 2006. In both years of testing, the untreated control received over 50% fruit damage from S. megarus. Bt and carbaryl pro- vided the highest level of control and the lowest level of fruit damage compared to all other treatments. Based on the results of this study, Bt appears to be an acceptable biological alter- native to the conventional insecticide (carbaryl) for control of S. megarus on pineapple. In addition, Bt was the least expensive treatment used in this study. © 2008 Elsevier B.V. All rights reserved. 1. Introduction The pineapple fruit borer, Strymon megarus (Godart) (Lep- idoptera: Lycaenidae), is one of the most economically important pests of pineapple, Ananas comosus (L.) Merr. (Coto and Saunders, 2004; Picado and Vásquez, 1997; EMBRAPA, 2005). Reports show that S. megarus can cause up to 80% dam- age in pineapple plantations in Brazil (EMBRAPA, 2005). In addition to pineapple, this pest has been reported on sev- eral other cultivated and wild plants, including Aphelandra deppeana; Brugmansia arborea; Capsicum spp.; Capsicum annuum var. annuum; Cordia sebestena; Hyptis sp.; Lantana sp.; Lan- ∗ Corresponding author at: The Ohio State University, Department of Entomology, 1680 Madison Avenue, Wooster, OH 44691, United States. Tel.: +1 330 263 3731; fax: +1 330 263 3686. E-mail address: Williams.14@osu.edu (R.N. Williams). tana camara; Mangifera indica; Solanum americanum; Solanum sanitwongsei; Solanum tuberosum; Stigmaphyllon emarginatum; Solanum melongena; Clerodendrum chinense; Hibiscus furcellatus (DAFF, 2002); Aechmea bracteata (Coto and Saunders, 2004). The fruit borer is widely distributed from Mexico throughout South America wherever pineapples are grown (DAFF, 2002; Coto and Saunders, 2004; Bérmudez, 2005). According to The Department of Agriculture, Fisheries and Forestry of Australia (DAFF, 2002) and Picado and Vásquez (1997), S. megarus primarily affects flowers and fruits. Dam- age caused by the larval stage is initiated at floral induction and continues until the last flowers emerge (Jiménez, 1999). 0925-8574/$ – see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.ecoleng.2008.07.005