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Master's Thesis from the year 2012 in the subject Agrarian Studies, printed single-sided, grade: -, Swedish University of Agricultural Sciences, course: Agroecology, language: English, abstract: Spodoptera littoralis is a major pest of cotton in Egypt, causing serious economic losses.Egyptian farmers highly appreciate biological control of the pest as synthetic pesticides arevery unsustainable. Phytophagous insects rely on plant volatiles to locate oviposition, feedingand, mating sites. We tested newly emerged S. littoralis moths by putting them in jars in indirectcontact with leaves of the host plant, Gossypium hirsutum (Gh) and of non-host plants,Adhatoda vasica (Av) and Picea abies (Pa). Combinations of host and non-host plant leaveswere also observed. Females kept with Gh leaves started calling earlier than the females in allnon-host and the control treatments. Moths exhibited delayed mating when Pa and Gh leaveswere offered in combination. Fecundity was reduced with strong to medium effect when Ghand Pa and, Gh and Av leaves were offered in combinations, respectively. Pair longevity wasdecreased in the absence of Gh leaves or the presence of Av and Pa leaves. Gaschromatogram electroantennographic detection (GC-EAD) study on the antennae of female S.littoralis moths revealed three bio-active peaks in headspace collections from Av and five inPa, which were subsequently identified through gas chromatography mass spectrometry (GCMS)by a combination of MS library searches, Kovats indices calculating, and matching theretention times with synthetic standards if available. The biological activity of syntheticstandards of the identified compounds was further confirmed through electro-antennogramdose-response tests (EAG). A comprehensive knowledge about these inhibitory effects of Avand Pa leaves or their combinations, or compounds derived from them, could lead tosustainable pest management policies.