Behavioural and electrophysiological responses of Triatoma dimidiata nymphs to conspecific faecal volatiles

The behavioural and electrophysiological (electroantennography) responses of the first two instars of Triatoma dimidiata (Hemiptera: Reduviidae) Latreille to fresh and dry faecal headspace volatile extracts from fifth instar conspecific nymphs and synthetic compounds were analysed in this study. Recently emerged nymphs (3-5 days) aggregated around filter paper impregnated with dry faeces and around filter paper impregnated with extracts from both fresh and dry faeces. Older first instars (10-15 days) and second instars aggregated around filter paper impregnated with fresh and dry faeces, and their respective headspace extracts. Dry faecal volatile extracts elicited the strongest antennal responses, followed by fresh faecal extracts. Gas chromatography−mass spectrometry analysis of dried faecal headspace volatiles demonstrated the presence of 12 compounds: 2-ethyl-1-hexanol, 1,2,4-trimethylbenzene, n-octadecane, n-nonadecane, n-eicosane, n-heneicosane, n-tricosane, n-pentaeicosane, n-hexaeicosane, n-octaeicosane, nonanal, and 4-methyl quinazoline. In fresh faecal headspace extracts, only nonanal was clearly detected, although there were other trace compounds, including several unidentified sesquiterpenes. Four of the 11 compounds tested individually elicited aggregation behaviour at concentrations of 100 ng/μL and 1 μg/μL. A blend containing these four components also mediated the aggregation of nymphs. These volatiles may be valuable for developing monitoring methods and designing sensitive strategies to detect and measure T. dimidiata infestation.

Bibliographic Details

Main Authors:	Gálvez Marroquín, Zitlalic Maestra autora 12874, Cruz López, Leopoldo Caridad Doctor autor 2083, Malo, Edi A. Doctor autor 5425, Ramsey Willoquet, Janine M. Doctora autora 14239, Rojas, Julio C. Doctor autor 5426
Format:	Texto biblioteca
Language:	eng
Subjects:	Triatoma dimidiata, Hemiptera, Insectos vectores, Compuestos volátiles, Electrofisiología, Artfrosur,
Tags:	Add Tag No Tags, Be the first to tag this record!