Fusarium subglutinans (Ascomycota: Nectriaceae) is known to have lethal effects on aphid species, while there are limited studies associated with other arthropods. In this study, the effect of different spore concentrations (1×104, 1×106 and 1×108 spores/ml) of F. subglutinans 12A, isolated from Aphis gossypii in Adana-Karataş (Turkey), was investigated on Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) females and on 2nd instar nymphs (only 1×106 spores/ml). The application method was by dipping and observations on mortality of females were conducted 24, 48, 72, 96 hours and 7 and 9 days after application. Mycosis was also observed on dead individulas. Mortality of nymphs was recorded during 8 days after application. Higher average dead females were found in the treatments compared to the control, but there was not significant difference between the tested concentrations (Mycosis rate recorded in 1×106 spores/ml was higher than those in 1×104 and 1×108 spores/ml). The highest and lowest mycosis rates were observed on the 7th and 3rd day, respectively. Average number of dead 2nd instar nymphs recorded in 1×106 spores/ml did not differ from control.
