Several studies have shown intraspecific geographical variation in the composition of sex pheromones. Pheromone lures from North America and Europe were not effective against the fall armyworm Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) in Brazil, so we examined the composition of the sex pheromone produced by females from Brazilian populations. Virgin female gland extracts contained (Z)-7-dodecenyl acetate (Z7-12:Ac), (E)-7-dodecenyl acetate (E7-12:Ac), dodecyl acetate, (Z)-9-dodecenyl acetate, (Z)-9-tetradecenyl acetate (Z9-14:Ac), (Z)-10-tetradecenyl acetate, tetradecyl acetate/(Z)-11-tetradecenyl acetate (Z11-16:Ac), and (Z)-11-hexadecenyl acetate. The relative proportions of each acetate were 0.8:1.2:0.6:traces:82.8:0.3:1.5:12.9, respectively. This is the first time that E7-12:Ac has been reported from the pheromone gland of S. frugiperda. Only three compounds, Z9-14:Ac, Z7-12:Ac, and E7-12:Ac, elicited antennal responses, and there were no differences in catch between traps baited with either Z7-12:Ac + Z9-14:Ac or Z7-12:Ac + Z9-14:Ac + Z11-16:Ac blends. However, the Z7-12:Ac + Z9-14:Ac + E7-12:Ac blend was significantly better than Z7-12:Ac + Z9-14:Ac, indicating that E7-12:Ac is an active component in the sex pheromone of the Brazilian populations of S. frugiperda.
High plaque levels at gingival margins after oral hygiene were observed in an unselected sample of young German adults. After 12 weeks, plaque levels after oral hygiene were slightly reduced in the group who had received training of the Fones technique but effects trailed off afterwards. The study failed to prove effects of the training on signs of gingival inflammation.
Virgin female gland extracts of sugarcane moth Diatraea saccharalis (Fabricius) (Lepidoptera: Pyralidae), from three locations in Brazil, have been analyzed. By GC-MS analysis and comparison of the chromatographic retention time of the components of the pheromone gland with those retention times of synthetic standards, we observed the presence of (Z)- hexadec-11-enal (1), hexadecanal (2), (9E,11Z)-hexadecadienal (4), (9Z,11Z)-hexadecadienal (5) and (9E,11E)-hexadecadienal (6), as minor components besides the major constituent (9Z,11E)-hexadecadienal (3) already reported. We found no variations in the composition of the gland extracts deriving from the three Brazilian populations and only two compounds, (Z)-hexadec-11-enal (1) and (9Z,11E)-hexadecadienal (3), elicited antennal responses (GCEAD). In electroantennography (EAG), however, pure compounds 1 and 3, a binary mixture containing 1 and 3, and a mixture containing all of the six synthetic compounds 1-6 elicited a depolarization in male antennae of D. saccharalis, without any statistically different delay. The EAG responses to the other isomers of 9,11-hexadecadienal were small and not significantly different from the control, except for the (9Z,11Z)-isomer (5) which showed an relatively strong electroantennal activity.
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