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The composition of the rectal gland secretion and volatiles emitted by female Queensland fruit fly, Bactrocera tryoni was investigated. Esters were found to be the main compounds in the gland extracts and headspace, while amides were the minor compounds in the gland extracts and headspace. Ethyl dodecanoate, ethyl tetradecanoate, ethyl (Z9)-hexadecenoate and ethyl palmitate were the main esters in the gland extracts, while ethyl dodecanoate and ethyl tetradecanoate were the main esters in the headspace. Four amides (N-(3-methylbutyl)acetamide), N-(2-methylbutyl)propanamide, N-(3-methylbutyl)propanamide, and N-(3-methylbutyl)-2-methylpropanamide were found in the gland extracts and the headspace. Among the amides, N-(3-methylbutyl)acetamide and N-(3-methylbutyl)propanamide were the main amides in the gland extracts and the headspace. Traces of three spiroacetals were found both in the gland extracts and in the headspace. (E,E)-2,8-Dimethyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-ethyl-8-methyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-propyl-8-methyl-1,7-dioxaspiro[5.5]undecane. All compounds found in the headspace were present in the extract of the rectal gland suggesting that the rectal gland is the main source of the headspace volatiles, whose function remains to be elucidated. This is the first comprehensive chemical analysis of the rectal gland secretions and volatiles of female B. tryoni, and further laboratory and field bioassays are required to determine the function of compounds identified in this study. Discovery of the same amides previously identified in the male rectal gland in the female rectal gland raises questions about the pheromonal role previously suggested for these compounds.

Research to discover and develop attractants for the codling moth, Cydia pomonella L., has involved identification of the chemicals eliciting moth orientation to conspecific female moths, host fruits, fermented baits, and species of microbes. Pear ester, acetic acid, and N-butyl sulfide are among those chemicals reported to attract or enhance attractiveness to codling moth. We evaluated the trapping of codling moth with N-butyl sulfide alone and in combination with acetic acid and pear ester in apple orchards. Acetic acid was attractive in two tests and N-butyl sulfide was attractive in one of two tests. N-Butyl sulfide increased catches of codling moth when used with acetic acid to bait traps. N-Butyl sulfide also increased catches of codling moth when added to traps baited with the combination of acetic acid and pear ester. Male and female codling moth both responded to these chemicals and chemical combinations. These results provide a new three-component lure comprising N-butyl sulfide, acetic acid, and pear ester that is stronger for luring codling moth females than other attractants tested.

Cost-effective detection of invasive ant colonies before establishment in new ranges is imperative for the protection of national borders and reducing their global impact. We examined the sampling efficiency of food-baits and pitfall traps (baited and nonbaited) in detecting isolated red imported fire ant (Solenopsis invicta Buren) nests in multiple environments in Gainesville, FL. Fire ants demonstrated a significantly higher preference for a mixed protein food type (hotdog or ground meat combined with sweet peanut butter) than for the sugar or water baits offered. Foraging distance success was a function of colony size, detection trap used, and surveillance duration. Colony gyne number did not influence detection success. Workers from small nests (0- to 15-cm mound diameter) traveled no3 m to a food source, whereas large colonies (30-cm mound diameter) traveled up to 17 m. Baited pitfall traps performed best at detecting incipient ant colonies followed by nonbaited pitfall traps then food baits, whereas food baits performed well when trying to detect large colonies. These results were used to create an interactive model in Microsoft Excel, whereby surveillance managers can alter trap type, density, and duration parameters to estimate the probability of detecting specified or unknown S. invicta colony sizes. This model will support decision makers who need to balance the sampling cost and risk of failure to detect fire ant colonies.

Synthetic female sex pheromone was used to monitor the phenology of male Ascogaster quadridentata Wesmael, an egg-larval parasitoid of codling moth, Cydia pomonella (L.), in conjunction with pheromone trapping of the moth and the banding of trees to determine larval parasitism. Catch of this parasitoid was typically ≈10 times less than the moth catch, and larval parasitism varied from 7 to 12%. The emergence of the parasitoid occurred slightly later than the female moth emergence, by both outdoor emergence cages and pheromone trapping. The seasonal activity of male parasitoids was otherwise synchronous with male codling moth flight. A survey of orchards in four regions of New Zealand showed considerable regional variation in the capture of the parasitoid in pheromone traps. The potential value of the parasitoid may be limited by the nil tolerance of the pest in export fruit, but pheromone trapping of this parasitoid could improve the understanding of biological control in non-export situations, w...

The temporal distribution of pheromone of Epiphyas postvittana (Walker) and its possible effect on communication disruption was investigated using field electroantennogram (EAG) measurements and insect traps. Three replicate matched pairs of blocks were pheromone-treated with 700 dispensers per hectare or left as untreated controls. An array of 9 delta traps was installed in the center of each block. Male catch in the traps baited with rubber septa containing pheromone was recorded daily, and the following weekly cycle was operated: disruptant pheromone dispensers were present in the field for 2 d, but were then removed from treated plots for 5 d. Significant disruption of trap catch occurred for the 2 d that dispensers were present, and for 1 additional night following their removal. Field EAG recordings of 3 min duration taken while the dispensers were present showed a high frequency of large pulses as fluctuations in pheromone concentration in the treated area. No comparable pulses were measured in the untreated control blocks or from 5 min to 1 h after the removal of the dispensers from the treated area. The frequency of the pheromone pulses in treated plots was positively correlated with wind speed. After removal of the dispensers from the treated plots, die mean EAG signal declined linearly, indicating a log-linear rate of drop in mean pheromone concentration. Our results show that the large fluctuations in pheromone concentration detected in EAG recordings arise from the dispensers. However, large fluctuations detectable by EAG do not seem to be required for mating disruption of E. postvittana .

To determine impact of point source distribution on communication disruption in Epiphyas postvittana (Walker), 100 dispensers releasing pheromone and inhibitor were deployed in replicated 0.5-ha New Zealand apple orchard blocks at 3 point source densities (1, 9, or 100 points), along with untreated control. Weekly inspections of pheromone-baited sticky traps were compared with field electroantennogram (EAG) recordings, of 3-min duration, which were made at 2 locations in the 4 treatments with the same antenna. EAG recordings were later normalized to the calibration pulses, and the mean squared error of the signal (MSE) was calculated. Assessment of spike size and frequency was also made. Significantly increased disruption of trap catches resulted from increased number of point sources. In pheromone-treated plots, 4 inner traps were more disrupted than were 12 outer traps. EAG signals in treated plots showed significantly higher numbers of spikes that exceeded a given signal-to-noise ratio (as defined from untreated sites). Spike size and spike frequency both increased with increasing numbers of point sources. The MSE signal from the EAG was also higher in the more dense of the pheromone treatments. The inverse relationship between spike frequency and catch suggests that aerial environments with higher spike frequencies are more effective at communication disruption. There appears to be value in using both the MSE and spike frequency recorded by EAG to characterize fluctuations in pheromone concentrations in treated orchards.

Mating disruption of Epiphyas postvittana (Walker) using Shin-Etsu dispensers that contained ( E )-11-tetradecenyl acetate and ( E , E )-9,11-tetradecadienyl acetate was investigated using pheromone traps, tethered virgin female moths, and assessment of larval damage in apples at harvest in small orchard blocks (

Disruption of Epiphyas postvittana mating behavior using synthetic pheromone was investigated in field cages and in replicated small-plot trials in a pine Pinus radiata (D. Don) plantation. Polyethylene tubing dispensers releasing two formulations were tested: 70% ( E )-11-tetradecenyl acetate and 30% ( Z )-11-tetradecenyl acetate (monoene) or 92.6% ( E )-11-tetradecenyl acetate, 2.8% ( Z )-11-tetradecenyl acetate, and 4.6% ( E,E )-(9,11)-tetradecadien-1yl acetate (monoene/diene). Field cage tests suggested that the second blend was the more effective disruptant, probably because of the presence of the diene. The concentration–response of males to the monoene/diene blend showed greater disruption of their normal response to caged females than the monoene alone ( P 500/ha of monoene in 100-m2 plots ( P < 0.01). The percentage of tethered virgin females that were mated also was significantly reduced in all monoene treatments ( P < 0.01) compared with untreated controls. In larger plots (900 m2), the highest rate of monoene (1,000 dispensers/ha) resulted in 17% mating of tethered females ( n = 64) compared with 93% mating in controls ( n = 57). However, the second blend containing monoene/diene applied at 1,000 dispensers/ha reduced the percentage of mated females to 0 ( n = 35), at an average pheromone release rate of 9.8 mg/ha per h. In a similar trial of the monoene/diene blend (900 m2 plots), 73% of females mated in control plots ( n = 80), compared with 1% ( n = 90) in plot treated with 1,000 dispensers/ha (9.5 mg/ha per h).