« Previous AbstractEcology and neurobiology of toxin avoidance and the paradox of drug reward    Next AbstractIndirect multi-trophic interactions mediated by induced plant resistance: impact of caterpillar feeding on aphid parasitoids »

PLoS One

Title:		Aphid honeydew quality as a food source for parasitoids is maintained in Bt cotton
Author(s):		Hagenbucher S; Wackers FL; Romeis J;
Address:		"Agroscope, Institute for Sustainability Sciences (ISS), Zurich, Switzerland. Centre for Sustainable Agriculture, Lancaster University, Lancaster, United Kingdom"
Journal Title:		PLoS One
Year:		2014
Volume:		20140916
Issue:		9
Page Number:		e107806 -
DOI:		10.1371/journal.pone.0107806
ISSN/ISBN:		1932-6203 (Electronic) 1932-6203 (Linking)
Abstract:		"Bt-transgenic cotton has proven to be highly efficient in controlling key lepidopteran pests. One concern with the deployment of Bt cotton varieties is the potential proliferation of non-target pests. We previously showed that Bt cotton contained lower concentrations of insecticidal terpenoids as a result of reduced caterpillar damage, which benefited the aphid Aphis gossypii. It is thus important that non-target herbivores are under biological control in Bt cotton fields. The induction or lack of induction of terpenoids could also influence the quality of aphid honeydew, an important food source for beneficial insects. We therefore screened A. gossypii honeydew for cotton terpenoids, that are induced by caterpillars but not the aphids. We then tested the influence of induced insect-resistance of cotton on honeydew nutritional quality for the aphid parasitoid Lysiphlebus testaceipes and the whitefly parasitoid Eretmocerus eremicus. We detected the cotton terpenoids gossypol and hemigossypolone in A. gossypii honeydew. Although a feeding assay demonstrated that gossypol reduced the longevity of both parasitoid species in a non-linear, dose-dependent manner, the honeydew was capable of sustaining parasitoid longevity and reproduction. The level of caterpillar damage to Bt and non-Bt cotton had no impact on the quality of honeydew for the parasitoids.These results indicate that the nutritional quality of honeydew is maintained in Bt cotton and is not influenced by induced insect resistance"
Keywords:		Animals *Aphids Bacillus thuringiensis/*genetics Bacillus thuringiensis Toxins Bacterial Proteins/*genetics Disease Resistance/*genetics Endotoxins/*genetics Gossypium/chemistry/*genetics/*parasitology Hemolysin Proteins/*genetics Herbivory Insecta Plant;
Notes:		"MedlineHagenbucher, Steffen Wackers, Felix L Romeis, Jorg eng Research Support, Non-U.S. Gov't 2014/09/17 PLoS One. 2014 Sep 16; 9(9):e107806. doi: 10.1371/journal.pone.0107806. eCollection 2014"