Using entomopathogenic flora of cotton whitefly Bemisia tabaci (Gennadius) (Hemiptera:Aleyrodidae) in microbial control

Cotton whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), causes important economic losses on different host plants in the world including Turkey. Besides predator and parasitoids, entomopathogenic bacteria, fungi and nematodes are used in the biological control of the pest. In this study, to determine, use of entomopathogen flora on microbial control of B. tabaci, bacteria and fungi isolated from B. tabaci samples collected from different plants in Adana and Mersin during 2013-2014. After isolation studies, putative 89 bacteria and 67 fungi were determined. Twelve bacterial and 15 fungal isolates were selected for biological effect bioassay. Among bacterial isolates, the efficacy of Serratia marcescens was 72% under laboratory conditions. The rates of other bacterial isolates were less than 25%. The efficacies of 15 fungal isolates ranged from 5 to 99%. The efficacies of eight isolates were among 66-99% when compared with control and the experiment was repeated. In the second experiment, the efficacies of fungal isolates were 57-98% and three isolates were selected for potted plants studies. Serratia marcescens were ineffective against immature stages of B. tabaci in the potted plants studies. In the potted plants studies, the highest efficacy rate with 65% was obtained from Penicillium oxalicum and this isolate was selected as a nominated entomopathogen for greenhouse studies. Although Penicillium oxalicum was effective in laboratory and potted plants studies, it was failt on adults and nymphs of B. tabaci in greenhouse studies. This study is the first study about determination of entomopathogen flora of B. tabaci in Turkey.