Efficacy of Single and Dual Gene Cotton <I>Gossypium Hirsutum</I> Events on Neonate and Third Instar Fall Armyworm, <I>Spodoptera Frugiperda</I> Development Based on Tissue and Meridic Diet Assays

Authors

  • J. Scott Armstrong
  • John J. Adamczyk, Jr.
  • Shoil M. Greenberg

Abstract

We evaluated mortality and developmental parameters of fall armyworms, Spodoptera frugiperda (J. E. Smith), to the single Bacillus thuringiensis (Bt) cotton trait, Bollgard® and dual Bt cotton traits (Bollgard II® and WideStrike™) by using a cotton leaf-tissue assay and by incorporating lyophilized cotton tissue into a meridic diet. Bioassays were conducted for both neonate and 3rd instars. Leaf tissue bioassays indicated that Bollgard II® and WideStrike™ are highly effective against fall armyworm neonates by causing mortality and by retarding development parameters such as larval weight, pupal duration, and time to adulthood. Bollgard® was not significantly different from non-transgenic cotton in terms of mortality or feeding, with the exception of the non-Bt (PhytoGen 425RF), which had an inherent form of resistance that is not associated with a transgenic event. Third instars evaluated with lyophilized diet bioassays were not as affected by the Bt traits to the same degree as neonates; however, larval weights were lower, and developmental parameters such as time to pupation and time to adulthood were longer. The duration of pupal development was significantly longer for 3rd instars that survived the highest dose of 5,000 µg of WideStrike™ cotton tissue. Sublethal doses for Bollgard II® and WideStrike™ were generally observed at 500 to 5,000 µg of lyophilized cotton tissue per mg of meridic diet, depending upon the variable (time to pupation, pupal duration, time to adult emergence) measured.

View this article in BioOne

Downloads

Published

2011-06-01

Issue

Vol. 94, No. 2 (June 2011)

Section

Research Papers

License

Copyright for any article published in Florida Entomologist is held by the author(s) of the article. Florida Entomologist is an open access journal. Florida Entomologist follows terms of the Creative Commons, Attribution Non-Commercial License (cc by-nc). By submitting and publishing articles in Florida Entomologist, authors grant the FOJ and Florida Entomologist's host institutions permission to make the article available through Internet posting and electronic dissemination, and to otherwise archive the information contained both electronically and in a hard printed version. When used, information and images obtained from articles must be referenced and cited appropriately. Articles may be reproduced for personal, educational, or archival purposes, or any non-commercial use. Permission should be sought from the author(s) for multiple, non-commercial reproduction. Written permission from the author(s) is required for any commercial reproduction.