Biological activity of Bt proteins expressed in different structures of transgenic corn against Spodoptera frugiperda

• Main Authors: Daniel Bernardi, Oderlei Bernardi, Renato Jun Horikoshi, Eloisa Salmeron, Daniela Miyuki Okuma, Celso Omoto
• Format: Article
• Language: English
• Published: Universidade Federal de Santa Maria 2016-06-01
• Series: Ciência Rural
• Subjects: lagarta-do-cartucho; Bacillus thuringiensis; milho Bt; manejo da resistência de insetos
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000601019&lng=en&tlng=en

ABSTRACT: Spodoptera frugiperda (J. E. Smith) is the main target pest of Bt corn technologies, such as YieldGard VT PRO(tm) (Cry1A.105/Cry2Ab2) and PowerCore(tm) (Cry1A.105/Cry2Ab2/Cry1F). In this study, it was evaluated the biological activity of Bt proteins expressed in different plant structures of YieldGard VT PRO(tm) and PowerCore(tm) corn against S. frugiperda . Complete mortality of S. frugiperda neonates was observed on leaf-disc of both Bt corn technologies. However, the mortality in silks and grains was lower than 50 and 6%, respectively. In addition, more than 49% of the surviving larvae in silks and grains completed the biological cycle. However, all life table parameters were negatively affected in insects that developed in silks and grains of both Bt corn events. In summary, the low biological activity of Bt proteins expressed on silks and grains of YieldGard VT PRO(tm) and PowerCore(tm) corn can contribute to the resistance evolution in S. frugiperda populations.