Search tips
Search criteria 


Logo of biolettersThe Royal Society PublishingBiology LettersAboutBrowse By SubjectAlertsFree Trial
Biol Lett. 2010 June 23; 6(3): 314–317.
Published online 2009 December 23. doi:  10.1098/rsbl.2009.0953
PMCID: PMC2880062

Is quality more important than quantity? Insect behavioural responses to changes in a volatile blend after stemborer oviposition on an African grass


Plants subjected to insect attack usually increase volatile emission which attracts natural enemies and repels further herbivore colonization. Less is known about the capacity of herbivores to suppress volatiles and the multitrophic consequences thereof. In our study, the African forage grass, Brachiaria brizantha, was exposed to ovipositing spotted stemborer, Chilo partellus, moths. A marked reduction in emission of the main volatile, (Z)-3-hexenyl acetate (Z3HA), occurred following oviposition but the ratio of certain other minor component volatiles to Z3HA was increased. While further herbivore colonization was reduced on plants after oviposition, the new volatile profile caused increased attraction of an adapted parasitoid, Cotesia sesamiae. Our results show that insect responses are dependent on the quality of volatile emission rather than merely the quantity in this multitrophic interaction.

Keywords: volatile emission, ratios, plant–insect interactions, multitrophic interactions

Articles from Biology Letters are provided here courtesy of The Royal Society