Title: | "Identification of Key Plant-Associated Volatiles Emitted by Heliothis virescens Larvae that Attract the Parasitoid, Microplitis croceipes: Implications for Parasitoid Perception of Odor Blends" |
Address: | "Department of Entomology & Plant Pathology, Auburn University, Auburn, AL, 36849, USA. Department of Entomology & Plant Pathology, Auburn University, Auburn, AL, 36849, USA. fadamhy@auburn.edu" |
DOI: | 10.1007/s10886-016-0779-7 |
ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Linking) |
Abstract: | "Herbivores emit plant-associated volatile organic compounds (VOCs) after feeding on plants. These plant-associated VOCs can be used by parasitoids to locate their hosts. It is hypothesized that certain compounds play key roles in the attractiveness of host-associated odor blends. The larval parasitoid, Microplitis croceipes (Hymenoptera: Braconidae) and its herbivore host, Heliothis virescens (Lepidoptera: Noctuidae), a major pest of cotton plant were used as model species to identify key compounds mediating attraction of parasitoids to hosts. Comparative GC/MS analyses of cotton-fed vs. artificial diet-fed hosts indicated that 12 of 17 compounds in the headspace of H. virescens larvae were exclusive to plant-fed hosts, and thus considered to be plant-associated. In order to identify key attractive compounds, a full blend of 15 commercially available synthetic compounds was modified by removing each of the 10 plant-associated compounds emitted by host larvae. In Y-tube olfactometer bioassays testing parasitoid responses to modified blends, 1-octen-3-ol, decanal, (E)-beta-caryophyllene, alpha-humulene, alpha-farnesene, and beta-pinene were identified as key compounds contributing to attractiveness of the natural blend of VOCs emitted by cotton-fed hosts. The results showed that while various host-associated compounds act in concert to serve as useful host location cues, only a fraction of the natural blend mediates attraction in parasitoids. Furthermore, the role of a compound is better assessed in the context of other compounds, and odor blends are better perceived as a whole rather than as individual components" |
Keywords: | Animals Gossypium/*chemistry Hymenoptera/drug effects/*physiology Larva/drug effects/*physiology Lepidoptera/*parasitology Odorants/*analysis Olfactory Perception/*drug effects Oviposition/drug effects Volatile Organic Compounds/analysis/pharmacology Vola; |
Notes: | "MedlineMorawo, Tolulope Fadamiro, Henry eng 2016/10/11 J Chem Ecol. 2016 Nov; 42(11):1112-1121. doi: 10.1007/s10886-016-0779-7. Epub 2016 Oct 8" |