Avaliação do milho Bt Cry1Ab e Cry1F no controle de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) em condições de campo

Abstract

The use of corn hybrids that express resistance to pests is increasing year by year in Brazil, due the need for increasing productivity and improving efficiency to control them. Because the occurrence of various biological systems, it becomes necessary to study the various technologies in Bt corn in producing regions in the country. This study aims to test the control of Cry1Ab and Cry1F Bt maize hybrids on Spodoptera frugiperda (J.E. Smith), to compare the productivity of Bt hybrids with their conventional isolines, besides to compare the production costs of transgenic and conventional hybrids in 2008/09 first crop, second crop in 2009 and 2010 in several districts of Mato Grosso do Sul State. We conducted visual assessments damage, productivity, stand (number of plants per hectare) and production costs. All hybrids with Bt technology showed high efficiency to control S. frugiperda. There was an increase in productivity of Bt hybrids when compared to the conventional one. The Bt hybrids stand was significantly higher than the conventional hybrids stand and the Bt production costs ranged from 1,0 to 1,9% higher than the conventional hybrids. The benefits of using transgenic hybrids are resulting from the increased productivity and the production costs that are similar to the production costs of conventional hybrids.