Biological Activity of Hyphomycete Entomopathogenic Fungi Against Gynaikothrips uzeli (Thysanoptera: Phlaeothripidae)

Weeping fig, Ficus benjamina L. (Moraceae) is an ornamental plant species grown worldwide. In Mexico, it is one of the most widely used ornamen tals in urban green areas. Leaves of the tree are damaged by the thrips Gynaikothrips uzeli Zim merman (Cambero et al. 2010). Thrips feed on leaf terminals and inject toxins causing deformed leaves and gall formation (Held et al. 2005; Ret ana-Salazar & Sanchez-Chacon 2009). Chemical control of Gynaikothrips spp. is possible (Held & Boyd 2008), but insecticides should be used wisely in order to preserve associated natural en emies (Wheeler et al. 2007). In Mexico, Montan doniola confusa Streito & Matocq and Andro thrips ramachandrai (Karny) have been found to be predators of Gynaikothrips spp (Cambero et al. 2010). In North America north of Mexico, A. ram achandrai, Montandoniola moraguesi Puton and Thripastichus gentilei (Del Guercio) are reported natural enemies (Held et al. 2005; Held & Boyd 2008). Microbial control could be integrated with nat ural enemies as an alternative to insecticides. En tomopathogenic fungi (Hyphomycetes) infecting thrips have been described, especially on Fran kliniella occidentalis (Pergande) and Thrips tabaci (Lindeman) (Gouli et al. 2008; Thungra beab et al. 2006). The Hyphomycetes are common and well known soil-borne pathogens in nature, with a wide range of insect hosts, and are consid ered excellent biological control agents (Gouli et al. 2008). Evaluations of entomopathogenic fungi noticeably are absent from previous research on control of G. uzeli (Held & Boyd 2008) or recent reviews (Held et al. 2005). The objective of this study was to test isolates of Beauveria bassiana (Balsamo) Vuillemin, Metarhizium anisopliae (Metschnikoff), and Paecilomyces fumosoroseus (Wize) against larvae and adults of G. uzeli under laboratory conditiona Thrips used in bioassays were collected from trees of F. benjamina located in gardens of the Universidad Autonoma de Nayarit, in Tepic, Na yarit, Mexico, located at 21°29'18.73"N, 104°53'25"W and 944 masl, and were transferred to the Parasitology Department of the Univer sidad Autonoma Agraria Antonio Narro, Mexico. Thrips were identified by M. S. Jhonathan Cam bero Campos. Entomopathogenic fungi were ob tained from different hosts (Table 1) and were maintained and propagated on potato dextrose agar with 2% yeast extract (PDAY) that was sup plemented with corn liquor to obtain pH 6.0. Pu rified fungi were identified according to their mi croand macroscopic characteristics (Humber 1997). Spores were stored under aseptic condi tions in 0.05% Tween 80 sterile distilled water so