Uso de Beauveria bassiana (Bals.) Vuill. no controle do Tetranychus urticae na cultura do morangueiro

Abstract

The aim of this study was to evaluate the use of Beauveria bassiana to control the spotted spider mite. The experiment was carried out at the University of Caxias do Sul. The treatments consisted of: Water (T1), Ballvéria® (Beauveria bassiana) at a dose of 1 kg/ha (T2), Ortus® (active ingredient: fenpiroximate), at the dose 500 ml/ha and Oberon® (active ingredient: spiromesifen), at a dose of 500 mL∙ha-1 (T3). Three strawberry leaf discs were inserted into Petri dishes, where they already contained moistened filter paper. Eight adult mites were placed on each leaf disc and left for 48 h for oviposition. After this period the adults were removed. For the egg test, the treatments were sprayed, separately, right after the adults were removed, and after 8 days, the hatched nymphs were counted. For the test with the nymphs, it was waited for 8 days after the removal of the adults and then the treatments were sprayed. Treatment in the adult mite stage resulted in mortality with treatment with Beauveria bassiana, in 89.7% of the individuals, with the chemical product Ortus ® it was observed 90.4% mortality of mites, and with control (water) there was 7.3% mortality of individuals. For the bioassay with the egg stage of the mite it was observed mortality of 93.7% of the individuals treated with Beauveria bassiana, with the chemical product Oberon ® it was found 97.9% mortality of eggs and for the treatment with water was 16.8% of individual mortality. [resumo fornecido pelo autor]