Biotech Updates

Effect of Bt Technology on Indirect Defense in Cotton via a Tritrophic Interaction

February 11, 2011

Bt technology has been increasingly adopted on a large scale in world agriculture over the past years. Thus, Maria Carolina Blassiolo Moraes and colleagues at Embrapa Genetic Resources and Biotechnology, Brazil conducted a study to analyze the effects of cry1Ac gene in various phenotypic traits of cotton (DeltaPine 404 Bt Bollgard® variety), particularly on the herbivore's emission of volatile compounds and on the attraction of egg parasitoid Trichogramma pretisoum.

Results of the study showed herbivore damaged Bt and non-Bt plants produced higher quantity of volatile compounds compared to undamaged plants. There is significantly higher number of egg parasitoids attracted by damaged plants than the undamaged plants. There is no significant difference in the ratios of the compound released in the damaged Bt and damaged non-Bt plants. Therefore, Bt technology in Bollgard cotton does not cause harmful effects on the release of volatile compounds and on the behavior of the egg parasitoid studied.