Controle de tortricídeos em macieira com duas formulações de Bacillus thuringiensis var. Kustaki em Fraiburgo-SC

Abstract

RESUMO -Grapholita molesta e Bonagota cranaodes são duas importantes pragas de pomares de macieira controlada por inseticidas. O objetivo deste estudo foi testar duas formulações de Bacillus thuringiensis var. kurstaki (Btk) para o controle desses tortricídeos. Parcelas de macieira 'Fuji' foram pulverizadas com Dipel PM e Dipel SC, nas concentrações de 100 mL por100 L de calda. A eficiência do Btk foi comparada com os inseticidas tebufenozide (Mimic 240 SC -90 ml por 100 L) e clorpyrifos (Lorsban 480 BR -150 mL por 100 L). Duas vezes por semana, eram avaliadas as capturas de pragas em armadilha do tipo Delta. As avaliações de danos nos frutos foram realizadas antes e na colheita, sendo classificados os frutos em função do agrupamento em cachopa e a sua localização na planta. Os tratamentos com Btk tiveram mais danos do que os químicos. Houve uma tendência de maiores danos na parte interna, próximo ao tronco das macieiras e o agrupamento dos frutos não influenciou na presença de danos. Ambas as formulações de Dipel foram eficientes quando comparados com Mimic e Lorsban. Termos para indexação: Grapholita molesta, Bonagota cranaodes, macieira, entomopatógeno. TORTRICID MOTH CONTROL IN APPLEWITH TWO FORMULATION OF Bacillus thuringiensis VAR. kustaki IN FRAIBURGO, SCABSTRACT -Grapholita molesta and Bonagota cranaodes are two key pests in apple orchards controlled by insecticides. The objective of the present study was to test two formulas of Bacillus thuringiensis var. kurstaki to control these tortricid moths. A plot of `Fuji´ apple trees were sprayed with Dipel PM and Dipel SC, at a concentration of 100mL per 100 l liquid. The efficiency of Btk was compared with the insecticides tebuphenozide (Mimic 240 SC -90 mL per 100 L) and chlorpyrifos (Lorsban 480 BR -150 mL per 100 L). The capture of pests in a Delta-type trap was assessed twice a week. Fruit damage was evaluated pre-and post-harvest and the fruit were classified by branch-end clustering and location on the plant. The treatments with B. thuringiensis were more damaged than those with chemical treatments. There were a tendency to have more damage in the internal part, close to the apple tree trunk and the fruit clustering did not influence damage occurrence. Both Dipel formulations were efficient in relation of Mimic and Lorsban.

Hematotoxicity of Bacillus thuringiensis as Spore-crystal Strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss Albino Mice

“…Unfortunately, this pest control management resulted in harmful outcomes such as the selection of resistant populations of insect pests, compromising the efficiency of control and forcing farmers to use increasingly high doses of pesticides [2][3][4]. Moreover, these chemical insecticides have harmful effects on human health and wildlife, leaving residues in food and the environment [2,3].…”

Efficacy of insecticides in fruit borer control and residues on sugar apple fruit

“…Regarding the B. thuringiensis-based insecticide, which acts on ingestion, a greater action was expected in reducing fruit borer symptoms because, theoretically, there would be sufficient time for caterpillar contamination when scraping fruit peel before penetration. Monteiro & Souza (2010) demonstrated that B. thuringiensis var. kurstaki-based formulations are as efficient as tebufenozide-and chlorpyrifos-based chemical products for controlling Grapholita molesta (Busck) and Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae) in the apple tree.…”

MORTALITY OF APPLE LEAFROLLER EXPOSED TO DIFFERENT Bacillus thuringiensis SUBSPECIES IN ARTIFICIAL DIET, IN THREE ASSESSMENT PERIODS

“…In Brazil, Btk is used for the control of Grapholita molesta (BUSCK, 1916) (Lepidoptera: Tortricidae), in apple trees (MONTEIRO and SOUZA, 2010), whose action affects other lepidoptera that occur simultaneously such as apple leafroller Bonagota salubricola (MEYRICK, 1937) (Lepidoptera: Tortricidae) (MONTEIRO and SOUZA, 2010).…”