Laboratory studies to control Ceratitis capitata (Wiedmann) (Diptera: Tephritidae) (Mediterranean fly) with Beauveria bassiana.

摘要

With the objective of selecting promising isolates of Beauveria bassiana for the control of Ceratitis capitata, several bioassays were carried out in the laboratory using the adult as the vulnerable stage for the parasitic infection with the entomopathogenic fungus. For isolate screening, a concentration of 5x109 VC m-2 of the fungus was used. The LC₉₀, media survival rate (MS), and insecticide compatibility were evaluated. Fungus production assays were also done. Insecticides Mercaptotion 100% CE [malathion] (LuparaReg.), and Dimetoato 40% CE [dimethoate] (Sistemico Icona) were evaluated for compatibility with the selected isolates. This was done by quantification of the conidia's viability in Petri dishes after treatments with 50, 100 and 200% of commercial doses of the insecticides. From 7 isolates evaluated (mortality 97-14%), Bb 26, Bb 259, Bb 132, and Bb 238 were selected. CL₉₀ values ranged from 1x109 to 3.8x1011 VC m-2 (Bb 238 and Bb 26, respectively). The MS of the isolates ranged between 7 and 12 days (for Bb 238 and Bb 26, respectively). The highest yields in production were 7x109 CFU mg-1 and 20.7 g conidia kg-1 of rice (Bb 26). All isolates were compatible to Mercaptotion. Bb 132 was the most compatible isolate to Dimetoato. In conclusion, laboratory assays allowed the selection of potential B. bassiana isolates to control C. capitata.