Field evaluation of soybean transgenic event DAS-81419-2 expressing Cry1F and Cry1Ac proteins for the control of secondary lepidopteran pests in Brazil

Luiz H Marques,Antonio C Santos,Boris A Castro,Valéria F Moscardini,Jaédino Rossetto,Oscar Arnaldo N Silva,Luiz Henrique S Zobiole,Pablo Valverde-Garcia,Jonathan M Babcock,Nicholas P Storer,Dwain M Rule,Odair A Fernandes

doi:10.1016/j.cropro.2017.02.014

Luiz H Marques, Antonio C Santos + Show 10 more

Open Access

https://doi.org/10.1016/j.cropro.2017.02.014

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Abstract

Genetically modified soybean with transgenic event DAS-81419-2 (Conkesta™ technology), expresses two Bacillus thuringiensis (Bt) derived proteins, Cry1Ac and Cry1F. Event DAS-81419-2 is a proposed new Integrated Pest Management (IPM) tool with demonstrated high efficacy for controlling the primary lepidopteran pests affecting soybean production in South America. Studies were conducted in Brazil from 2011 to 2016 to assess the efficacy of DAS-81419-2 against secondary lepidopteran pests including Elasmopalpus lignosellus, Agrotis ipsilon and Helicoverpa armigera, using artificial infestations to ensure uniform pest pressure. Results from research trials across nine localities showed that compared to a non-Bt isoline, DAS-81419-2 significantly reduced the seedling stage plant mortality caused by E. lignosellus and the feeding damage caused by H. armigera during both vegetative and reproductive crop growth stages. Event DAS-81419-2 showed moderate activity on A. ipsilon, and additional control tactics such as a chemical insecticide applied as a seed treatment or spray during early crop stages may be needed against this pest to provide consistently higher levels of protection in fields that are at risk of infestation. Collectively, the efficacy of soybean transgenic event DAS-81419-2 for the control of secondary lepidopteran pests, added to its high efficacy on primary lepidopteran pests suggest this new, dual protein technology will be an important tool where primary and secondary pests affect soybean production.

Highlights

Soybean, Glycine max (L.) Merrill (Fabaceae: Phaseoleae) is one of the most important legume crops worldwide
Plant mortality during the seedling stage of soybean caused by E. lignosellus was significantly lower on Bacillus thuringiensis (Bt) soybeans containing the DAS-81419-2 event, compared with the non-Bt isogenic line 28 days after infestation (DAI) (F1,28 1⁄4 127.29, P < 0.0001)
Recent studies from South America indicate that Bt transgenic technology in soybeans are highly effective against the main lepidopteran pests (Bernardi et al, 2012, 2014; Marques et al, 2016)

Summary

Introduction

Glycine max (L.) Merrill (Fabaceae: Phaseoleae) is one of the most important legume crops worldwide. It has experienced the highest percentage increase in planted area since the 1970s compared to any other major crop and is grown in approximately 6% of the world's arable land (Hartman et al, 2011). L.H. Marques et al / Crop Protection 96 (2017) 109e115 lepidopteran pests including Elasmopalpus lignosellus (Zeller, 1848) (Viana, 2007; Hoffmann-Campo et al, 2012; Afonso-Rosa, 2013), Agrotis ipsilon (Hufnagel) (Hoffmann-Campo et al, 2012; Ferreira et al, 2015) and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) (Specht et al, 2013; Pomari-Fernandes et al, 2015) have been recently observed in Brazil. In the case of H. armigera, a recently introduced pest (Czepak et al, 2013), it is considered an emerging key pest in some Brazilian crop producing areas and requires close attention in terms of monitoring and control tactics

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