Major sex pheromone components of the Australian gum leaf skeletonizer Uraba lugens: (10E,12Z)-hexadecadien-1-yl acetate and (10E,12Z)-hexadecadien-1-ol.

Two sex pheromone components of the gum leaf skeletonizer, Uraba lugens (Lepidoptera: Nolidae), recently established in New Zealand, were identified. Gas chromatography (GC) electroantennographic detection analyses of female pheromone gland extracts gave three compounds that consistently elicited antennal responses. Chemical analyses, using GC and GC-mass spectrometry, in conjunction with 4-methyl-1,2,4-triazoline-3,5-dione and dimethyldisulfide derivatizations, identified these compounds as (10E,12Z)-hexadecadien-1-yl acetate (E10,Z12-16:Ac), (10E,12Z)-hexadecadien-1-ol (E10,Z12-16:OH), and (Z)-11-hexadecen-1-yl acetate (Z11-16:Ac). A trapping trial in Queensland, Australia, in 2002, indicated that a blend of the two major components E10,Z12-16:Ac and E10,Z12-16:OH could attract gum leaf skeletonizer males. In the same trial, E10,Z12-16:Ac alone trapped large numbers of an unidentified nolid, Nola spp. Further trials in Auckland, New Zealand established that these two components were sufficient and necessary for trap catch of males; adding minor gland components, (10E,12E)-hexadecadien-1-yl acetate (E10,E12-16:Ac), Z11-16:Ac, or octadecan-1-ol (18:OH), to the two-component lure did not result in increased trap catches. Behavioral observations and gland analyses of the Auckland population revealed that female moths begin calling soon after emergence, with peak calling and pheromone production occurring 7 hr into the scotophase. Analysis of gland extract at two-hourly intervals during the first activity period showed that the ratio of E10,Z12-16:Ac to E10,Z12-16:OH (mean of 86: 14, respectively) and pheromone titer were fairly constant. No qualitative or quantitative differences in pheromone components were detected between gland extracts from Tasmanian univoltine and Auckland bivoltine populations of U. lugens.

Synthesis of deuterated gamma-lactones for use in stable isotope dilution assays.

Two syntheses of deuterated gamma-lactones for use as internal standards in stable isotope dilution assays (SIDA) were developed. [2,2,3,3-2H4]-gamma-Octa-, -gamma-deca-, and -gamma-dodecalactones with >89% deuterium incorporation were prepared in 27, 17, and 19% overall yields, respectively, by the reduction of a doubly protected hydroxypropiolic acid with deuterium gas. [3,3,4-2H3]-gamma-Octa- and -gamma-dodecalactones were prepared in 6 and 23% yields with >92% deuterium incorporation by the free radical addition of 2-iodoacetamide to [1,1,2-2H3]-1-hexene and [1,1,2-2H3]-1-decene, respectively. Reaction yields were highly dependent upon the purity of the 1-alkene starting material. The deuterated gamma-lactones were evaluated as internal standards for SIDA.

Actinidia arguta: volatile compounds in fruit and flowers.

More than 240 compounds were detected when the volatile components of the flowers and the fruit from several Actinidia arguta genotypes were investigated. Around 60-70 different compounds were extracted from individual tissues of each genotype. Two different methods of volatile sampling (headspace and solvent) favoured different classes of compounds, dependent upon their volatilities and solubilities in the flower or fruit matrices. The compounds extracted from flowers largely comprised linalool derivatives including the lilac aldehydes (12a-d) and alcohols (13a-d), 2,6-dimethyl-6-hydroxyocta-2,7-dienal (8), 8-hydroxylinalool (9), sesquiterpenes, and benzene compounds that are presumed metabolites of phenylalanine and tyrosine. Extracts of fruit samples contained some monoterpenes, but were dominated by esters such as ethyl butanoate, hexanoate, 2-methylbutanoate and 2-methylpropanoate, and by the aldehydes hexanal and hex-E2-enal. A number of unidentified compounds were also detected, including 8 from flowers that are so closely related that they are either isomers of one compound or two or more closely related compounds. This is the first report of the presence of a range of linalool derivatives in Actinidia.