Cuelure but not zingerone make the sex pheromone of male Bactrocera tryoni (Tephritidae: Diptera) more attractive to females

In tephritid fruit flies of the genus Bactrocera Macquart, a group of plant derived compounds (sensu amplo ‘male lures’) enhance the mating success of males that have consumed them. For flies responding to the male lure methyl eugenol, this is due to the accumulation of chemicals derived from the male lure in the male rectal gland (site of pheromone synthesis) and the subsequent release of an attractive pheromone. Cuelure, raspberry ketone and zingerone are a second, related group of male lures to which many Bactrocera species respond. Raspberry ketone and cuelure are both known to accumulate in the rectal gland of males as raspberry ketone, but it is not known if the emitted male pheromone is subsequently altered in complexity or is more attractive to females. Using Bactrocera tryoni as our test insect, and cuelure and zingerone as our test chemicals, we assess: (i) lure accumulation in the rectal gland; (ii) if the lures are released exclusively in association with the male pheromone; and (iii) if the pheromone of lure-fed males is more attractive to females than the pheromone of lure-unfed males. As previously documented, we found cuelure was stored in its hydroxyl form of raspberry ketone, while zingerone was stored largely in an unaltered state. Small but consistent amounts of raspberry ketone and β-(4-hydroxy-3-methoxyphenyl)-propionic acid were also detected in zingerone-fed flies. Males released the ingested lures or their analogues, along with endogenous pheromone chemicals, only during the dusk courtship period. More females responded to squashed rectal glands extracted from flies fed on cuelure than to glands from control flies, while more females responded to the pheromone of calling cuelure-fed males than to control males. The response to zingerone treatments in both cases was not different from the control. The results show that male B. tryoni release ingested lures as part of their pheromone blend and, at least for cuelure, this attracts more females.     

Rate of pheromone release by individual spruce budworm moths

The rate and temporal pattern of pheromone emission by single and grouped female spruce budworm moths were measured by combining the trapping of pheromone on Porapak Q with a rapid luciferase bioassay developed for aldehyde pheromone. Pheromone release occurred mainly during the scotophase of a 12:12 L:D cycle in a series of bursts (up to 50 ng/hr) with considerable variability observed between insects. Analysis of over 30 individual females showed that 30% release no detectable pheromone, 60% release between 20 and 100 ng of pheromone and 10% release greater than 100 ng in a 24-hr period. Overall, a single female (1–3 days old) released an average of 60 ± 50 ng (± S.D.) of pheromone per night with a total of 260 ± 210 ng (± S.D.) being released over its life span (～7 days). Grouped females released lower quantities of pheromone. The amount of pheromone in the glands of female moths also displayed a rhythm with the levels beings higher later in the day than at the start of the photophase.     

Monitoring codling moth (Lepidoptera: Tortricidae) in sex pheromone-treated orchards with (E)-4,8-dimethyl-1,3,7-nonatriene or pear ester in combination with codlemone and acetic acid

Traps baited with ethyl (E,Z)-2,4-decadienoate (pear ester) or (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) in two- or three-way combinations with the sex pheromone (E,E)-8,10-dodecadien-1-ol (codlemone) and acetic acid (AA) were evaluated for codling moth, Cydia pomonella (L.). All studies were conducted in apple orchards, Malus domestica Borkhausen, treated with sex pheromone dispensers during 2010. Septa were loaded with codlemone, DMNT, and pear ester individually or codlemone with either DMNT or pear ester together (combo lures). Polyethylene vials loaded with AA were added as a co-lure. Residual analyses of field-aged combo lures and weight loss of the AA co-lure were conducted. AA vials lost 50-150 mg wk(-1). Weekly weight loss was not affected by field aging, but was closely correlated with the daily mean temperature. Pear ester was released from septa at a slightly higher but nonsignificant rate than codlemone. DMNT was released at a significantly higher rate than codlemone, and lures were effective for 4 wk. The addition of codlemone to traps baited with either host plant volatile plus AA had either no effect or significantly increased total moth catches. The addition of AA significantly increased the catch of female moths with either combo lure. Total moth catches in traps baited with pear ester or DMNT combo lures and AA did not differ and were either significantly higher or similar to the pear ester combo lure. These data suggest that codling moth may be more effectively monitored in sex pheromone-treated orchards with multi-component lures, including codlemone, AA, and host plant volatiles.     

Field trials of aggregation pheromones for the stink bugs Chlorochroa uhleri and Chlorochroa sayi (Hemiptera: Pentatomidae)

In field trials, adult Chlorochroa uhleri (St?l) (Heteroptera: Pentatomidae) of both sexes were caught in significant numbers in cylindrical screen traps baited with gray rubber septum lures loaded with the main component of the male-produced pheromone, methyl (E)-6-2,3-dihydrofarnesoate. Addition of the two possible minor components of the pheromone, methyl (E)-5-2,6,10-trimethyl-5,9-undecadienoate and methyl (2E,6E)-farnesoate, did not affect attraction. Combining the pheromone with different concentrations of volatiles mimicking the odors of a known host plant, alfalfa (Medicago sativa L.), had no significant effect on attraction of adult bugs, whereas combining the pheromone with the pheromones of two sympatric stink bug species, Chlorochroa sayi (St?l) and Euschistus conspersus Uhler, decreased trap captures, suggesting interference between the pheromones. Small numbers of Chlorochroa ligata (Say) adults also were attracted, but numbers caught were too low to allow statistical comparisons between lure blends. In field trials with C. sayi, all three of the male-specific pheromone compounds [methyl geranate, methyl citronellate, and methyl (E) -6-2,3-dihydrofarnesoate] were required for optimal attraction. As with C. uhleri, adults of both sexes were attracted to pheromone lures in approximately equal numbers. Because of the decreased volatility (=release rate) of methyl (E)-6-2,3-dihydrofarnesoate in comparison with the other two, lower molecular weight pheromone components, lures needed to be loaded with a disproportionately high amount of methyl (E)-6-2,3-dihydrofarnesoate to obtain the best trap catch. There was no indication that the pheromone components of C. uhleri or E. conspersus interfered with the attractiveness of the C. sayi pheromone in lures containing a blend of all three pheromones.     

Pheromone-mediated mating disruption of Choristoneura rosaceana: is the most attractive blend really the most effective?

An attractive four-component pheromone blend containing a major component Z11-tetradecenyl acetate, and three minor components, E11-tetradecenyl acetate, Z11-tetradecenyl alcohol, and Z11-tetradecenyl aldehyde was tested as a mating disruptant against western Canadian populations of the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), in organic apple orchards in British Columbia. Efficacy of this four-component blend was compared to that of partial pheromone blends containing the major component plus one or two minor components. A trapping experiment confirmed that, Conrel® fibre disruption dispensers containing the four-component blend were more attractive than disruption dispensers containing the two- or three-component partial blends. A small-plot protocol was followed to compare atmospheric treatments with these blends as mating disruptants at a release rate of 10 mg ha–1 h–1 and from 1000 dispensers ha–1. Mechanisms of mating disruption, such as false-trail following and camouflage of pheromone plumes, that may be evoked to a greater degree by an attractive blend, did not appear to augment the effectiveness of mechanisms invoked by the less attractive blends, as the proportion of mating among tethered females was equal in plots treated with these blends and was reduced by 85–90% compared to the nontreated control. When the four-component pheromone blend was tested at different release rates, mating disruption in small plots began to break down at a release rate of 1.3 mg ha–1 h–1 using a dispenser density of 1000 ha–1. Above 1.3 mg ha–1 h–1 there was no dose response in release rates tested and at release rates below this dose the proportion of tethered females mating was the same as in the nontreated control. The four-component pheromone blend was tested against, and found to be no more effective than, the two-component partial blend at the threshold release rate of 1.3 mg ha–1 h–1 when it was released from 1000 or 250 disruption dispensers. Our results suggest that disruption mechanisms evoked by the attractive blend did not enhance the mating disruption effect provided by the simple blend, therefore a two-component blend may be useful in an operational mating disruption program for C. rosaceana.     

Enzymatic Improvement of Food Flavor IV. Oxidation of Aldehydes in Soybean Extracts by Aldehyde Oxidase

Aldehyde oxidase (aldehyde: oxygen oxidoreductase, EC 1.2.3.1) was partially purified from bovine liver. The enzyme irreversibly oxidized various aldehydes to the corresponding acids by using dissolved oxygen as an electron acceptor. Although the Km value for n-hexanal was low (6 µm), that for acetaldehyde was high (20 mm).

Medium-chain aldehydes such as hexanal and pentanal appear to be mainly responsible for green beany odor of soybean products. A great reduction in the beany odor was observed after the soybean extract was incubated with aldehyde oxidase under aerobic conditions. Dissolved oxygen was utilized as the electron acceptor throughout the enzyme-catalyzed oxidation of aldehydes and none of other cofactors were found to be required.

It has been shown that bovine liver mitochondrial aldehyde dehydrogenase oxidizes the soybean protein-bound aldehyde with a rate comparable to that for free n-hexanal (Agric. Biol. Chem., 43, in press). Comparative studies of aldehyde oxidase and aldehyde dehydrogenase with respect to oxidation-rates of free aldehydes and the soybean protein-bound aldehydes indicated that aldehyde oxidase acted on the bound aldehyde with a much slower rate.     

Antennal-specific pheromone-degrading aldehyde oxidases from the moths Antheraea polyphemus and Bombyx mori

Female moths produce blends of odorant chemicals, called pheromones. These precise chemical mixtures both attract males and elicit appropriate mating behaviors. To locate females, male moths must rapidly detect changes in environmental pheromone concentration. Therefore, the regulation of pheromone concentration within antennae, their chief organ of smell, is important. We describe antennal-specific aldehyde oxidases from the moths Antheraea polyphemus and Bombyx mori that are capable of catabolizing long chain, unsaturated aldehydes such as their aldehyde pheromones. These soluble enzymes are associated uniquely with male and female antennae and have molecular masses of 175 and 130 kDa, respectively. The A. polyphemus aldehyde oxidase has been localized to the olfactory sensilla which contain the pheromone receptor cell dendrites. These same sensilla contain a previously described sensilla-specific esterase that degrades the acetate ester component of A. polyphemus pheromone. We propose that sensillar pheromone-degrading enzymes modulate pheromone concentration in the receptor space and hence play a dynamic role in the pheromone-mediated reproductive behaviors of these animals.     

Removal of mixtures of acetaldehyde and propionaldehyde from waste gas in packed column with immobilized activated sludge gel beads

The removal of mixed acetaldehyde and propionaldehyde as a model of the binary contaminants in waste gas was studied in the packed column containing the immobilized activated sludge gel beads together with the hollow plastic balls developed for the removal of a single aldehyde in the previous work. The rate of each aldehyde biodegradation by the gel beads in the aldehydes mixture was expressed by the Michaelis-Menten type rate equation with an inhibitory term due to the other coexistent aldehyde. The kinetic parameters involved were found to be the same as those determined previously for biodegradation of a single aldehyde. A model for prediction of removal of each aldehyde in the packed column was developed assuming that each aldehyde dissolved in the aqueous phase within the gel bead was biodegraded according to the above rate equation with no mass transfer effect. The packed column was stable and efficient for removal of the binary aldehydes mixture with a very low pressure drop for gas flow due to a reduced gel beads bed compaction by the hollow plastic balls. Removal of each aldehyde decreased with increasing the inlet aldehyde concentrations since each biodegradation rate itself approached asymptotically the maximum one with increase in each aldehyde concentration. The observed removals for each aldehyde in the aldehydes mixture agreed well with those calculated from the design equations developed. The contact efficiency of gel beads with the waste gas stream was estimated to be the same value of 0.24 as in the previous work, supporting that the efficiency was specific to the geometrical and physical properties of the packed column used.     

植物挥发性物质对蚜虫性信息素诱蚜效果的影响(英文)

本研究首先是在不同的寄主植物中利用蚜虫性信息素进行田间诱蚜实验。结果表明寄主植物影响性信息素田间诱蚜的种类和效果。在桃园 ,以蚜虫性信息素荆芥内酯和荆芥醇为性诱剂的水盆诱捕器 ,诱到 3种蚜虫的雄蚜 ,分别是桃蚜、桃粉大尾蚜和莲缢管蚜。其中 ,桃蚜占绝大多数 ,且还被性信息素的单一组分植物提取的荆芥内酯所吸引。麦田中诱到的雄蚜为麦二叉蚜。苹果园中诱到的雄蚜是绣线菊蚜和梨中华圆尾蚜 ,且性信息素诱捕器中的数目远多于对照诱捕器。据田间诱蚜实验结果推测 ,荆芥内酯和荆芥醇对桃粉大尾蚜有吸引作用 ,荆芥内酯可能是绣线菊蚜和梨中华圆尾蚜性信息素的一个组分。另外进行的田间实验表明寄主植物挥发性物质对蚜虫性信息素诱蚜效果有影响 ,当荆芥内酯诱捕器同时释放桃叶挥发物时 ,诱到的桃蚜雄蚜数量明显增加。触角电位记录实验也表明桃蚜雄蚜对桃叶挥发物和桃芽挥发物有反应。     

植物气味化合物与斜纹夜蛾性信息素的协同作用

为提高现有性信息素对雄蛾的引诱活性, 本研究通过大量的田间试验探索植物气味化合物与斜纹夜蛾Spodoptera litura性信息素（顺9, 反11-十四碳二烯乙酸酯∶顺9, 反12-十四碳二烯乙酸酯=10∶1）的协同作用机制。从斜纹夜蛾寄主植物和花的气味化合物中, 选择9种有代表性的化合物, 并以一定剂量分别加入到斜纹夜蛾性信息素诱芯中, 在田间测试对雄蛾的引诱活性。结果表明: 在测试的9种植源性化合物中, 发现一定剂量(每个诱芯加入0.4 mg)的苯乙醛(PAA), 具有显著提高斜纹夜蛾性信息素的引诱作用, 而高剂量的苯乙醛则强烈抑制性信息素的引诱活性; 此外, 其他各种浓度的测试化合物或混合物对性信息素则没有统计上显著的增效作用。不同剂量的苯乙醛单个化合物及各种植物气味化合物组成的混合物对斜纹夜蛾也有微弱的引诱作用。苯乙醛必须要与性信息素的完整组分(以10∶1比例混合的顺9, 反11-十四碳二烯乙酸酯和顺9反, 12-十四碳二烯乙酸酯)混合才能起作用, 缺少顺9, 反12-十四碳二烯乙酸酯则没有引诱活性。本研究证明, 苯乙醛作为理想的性信息素诱芯增效剂, 可应用于建立更理想的斜纹夜蛾性信息素诱杀技术, 对性诱害虫防治和测报具有应用价值。     

Modulatory role of testosterone in alarm pheromone release by male rats

An alarm pheromone released from stressed conspecifics evokes behavioral and autonomic responses in rats. We have previously reported that male Wistar rats show behavioral changes including increased sniffing, walking and rearing, and decreased resting as well as exaggerated response of body temperature to a novel environment [known as stress-induced hyperthermia (SIH)] when they are exposed to an alarm pheromone released from other male rats receiving foot shocks. The purpose of the present study was to examine the role of testosterone in the production and release of the alarm pheromone using these behavioral and autonomic responses in recipient rats. Three groups of alarm pheromone donors were presented, namely, intact males, castrated males, and testosterone-implanted castrated males. The effects of the alarm pheromone on the autonomic responses did not differ among the three groups, regardless of the donor's steroidal milieu, whereas behavioral responses were altered by castrating the donor males and the effects were restored by testosterone implantation. These results suggest that the alarm pheromone released from stressed male rats can be classified into at least two categories according to the androgen dependency of their production and/or release.     

Detection of pheromone biosynthetic and degradative enzymes in vitro

Highly sensitive, luminescent assays have been developed to measure enzyme activities involved in the metabolism of a major class of insect pheromones which includes fatty aldehydes, alcohols, and their acetate esters. These assays have been applied to measure the in vitro biosynthesis and degradation of the sex pheromone (trans:cis-11-tetradecenal, 96:4) of the eastern spruce budworm, Choristoneura fumiferana. Three activities were detected on analyses of extracts of the female moths: (a) an esterase that hydrolyzes both the cis and trans isomers of 11-tetradecenyl acetate, (b) an oxidase that converts fatty alcohols to aldehydes in the presence of O2, and (c) an NAD-dependent aldehyde dehydrogenase. The coupled luminescent response of bacterial luciferase to long chain aldehydes was used to measure rates of reaction as low as 0.1 pmol/min since only low amounts of material can be analyzed. Specific activities of these enzymes were higher in the pheromone producing gland than in other parts of the moth, implicating these enzymes, and the oxidase in particular, in the pathway of pheromone biosynthesis. The pathway was supported in vivo by demonstrating that topical application of 3H-labeled tetradecanyl acetate onto the insect gland resulted in the formation of [3H]tetradecanol and [3H]tetradecanoic acid, thus providing evidence that all three enzymes were functional in the living insects.     

Field evaluation of effect of temperature on release of disparlure from a pheromone-baited trapping system used to monitor gypsy moth (Lepidoptera: Lymantriidae)

Traps baited with disparlure, the synthetic form of the gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), sex pheromone are used to detect newly founded populations and estimate population density across the United States. The lures used in trapping devices are exposed to field conditions with varying climates, which can affect the rate of disparlure release. We evaluated the release rate of disparlure from delta traps baited with disparlure string dispenser from 1 to 3 yr across a broad geographic gradient, from northern Minnesota to southern North Carolina. Traps were deployed over approximately 12 wk that coincided with the period of male moth flight and the deployment schedule of traps under gypsy moth management programs. We measured a uniform rate of release across all locations when considered over the accumulation of degree-days; however, due to differences in degree-day accumulation across locations, there were significant differences in release rates over time among locations. The initial lure load seemed to be sufficient regardless of climate, although rapid release of the pheromone in warmer climates could affect trap efficacy in late season. Daily rates of release in colder climates, such as Minnesota and northern Wisconsin, may not be optimal in detection efforts. This work highlights the importance of local temperatures when deploying pheromone-baited traps for monitoring a species across a large and climatically diverse landscape.     

Evaluation of mass trapping and mating disruption for managing Prionus californicus (Coleoptera: Cerambycidae) in hop production yards

Larvae of Prionus californicus Motschulsky (Coleoptera: Cerambycidae) feed on the roots of many types of woody perennial crops and are serious pests of hop in the northwestern United States. The adult males are strongly attracted to a volatile sex pheromone, (3R,5S)-3,5-dimethyldodecanoic acid, that is produced by females. Here, we summarize the results of field experiments that evaluated the potential for using the synthetic pheromone (in a blend of all four possible stereoisomers) to manage infestations of P. californicus in commercial hop yards by mass trapping or mating disruption. Our research provides evidence that mass trapping may be effective in reducing mating success of the females: positioning surrogate females (sentinel traps baited with a low dose of pheromone) within a square of eight pheromone-baited traps resulted in an 88% reduction in the number of wild males that reached the sentinel traps compared with sentinel traps that were surrounded by traps baited with blank lures. Similarly, surrogate females that were surrounded by pheromone lures (without traps) were reached by 84% fewer wild males than surrogate females surrounded by blank lures, suggesting that mating disruption also may be effective. A mark-recapture experiment indicated that male P. californicus were attracted to traps baited with 1 mg of pheromone from as far away as 585 m. These studies indicate that 3,5-dimethyldodecanoic acid has very good potential for managing P. californicus in hop yards, and perhaps in other crops where it is a pest.     

Periodicity of sex pheromone biosynthesis, release and degradation in the lightbrown apple moth, Epiphyas postvittana (Walker)

Pheromone titer in moths is a product of three processes occurring in or at the surface of the pheromone gland: biosynthesis, release, and intraglandular degradation, of pheromone. Changes in titers of sex pheromone, the fatty acyl pheromone analog (FAPA), and tetradecanoate, a pheromone biosynthetic intermediate, were studied in detail in the lightbrown apple moth, Epiphyas postvittana (Walker). Although changes in the pheromone titers in a day were relatively small, with the peak titer being 2-3 times greater than that at the trough, pheromone titer did show a distinct diel periodicity. Titer of the FAPA showed a similar, but less variable, diel pattern, but tetradecanoate titer showed little or no diel pattern. The pattern of pheromone titer suggested that females biosynthesize pheromone at two different rates during the photoperiod: a high rate during the latter half of the photophase and most of the scotophase, which is associated with a high pheromone titer, and a low rate throughout the first half of the photophase, which is associated with a low titer. Consistent with data on commencement of copulation, pheromone was released from the second hour of the scotophase through to the eighth hour. Pheromone release rate during this period appeared to be similar to the rate of pheromone biosynthesis. In contrast to the other two processes, pheromone degradation did not appear to have a diel pattern. Females decapitated at different times of the photoperiod showed a similar decline in pheromone titer, consistent with the reaction kinetics being first order in pheromone titer.     

Semiochemical lures reduce emigration and enhance pest control services in open-field predator augmentation

Augmentation biocontrol is a commercially viable pest management tactic in enclosed glasshouse environments, but is far less effective in open-field agriculture where newly released enemies rapidly disperse from release sites. We tested the potential for behavior-modifying semiochemicals to increase the retention of mass released predatory stink bugs, Podisus maculiventris Say (Hemiptera: Pentatomidae), for enhanced consumption of hornworm caterpillars, Manduca sexta L. (Lepidoptera: Sphingidae). To do so, we used controlled-release dispensers to emit the herbivore-induced plant volatile, methyl salicylate (MeSA), or P. maculiventris aggregation pheromone from tomato field plots. Overall, we recaptured ca. 17% of released individuals after 36 h. This rate, however, was significantly affected by weather (12% vs. 22% recapture in rainy vs. dry weeks, respectively) and semiochemical deployment, but only under optimal weather conditions (19% vs. 26% recapture in control vs. pheromone plots, respectively, during dry weeks). Further, we detected behavioral responses of wild P. maculiventris to semiochemical treatment with 94% of all captured adults (=84 of 89 total) found in pheromone plots. Only 24 of 567 (4%) captured stink bugs tested positive for immunomarking, suggesting that hornworm predation occurred but at a low frequency. Importantly, we documented that sentinel caterpillar prey were depleted by predators at a higher rate in stink bug augmented plots on tomato plants occurring near (<3 m from) the MeSA and pheromone lures. These data empirically demonstrate that both semiochemicals are capable of increasing pest consumption via attraction of P. maculiventris. Future work should focus on mechanisms of lure attraction and the long-term consequences of predator development in fields with elevated semiochemical emissions.     

Response of plum curculio (Coleoptera: Curculionidae) to odor-baited traps near woods.

Response of overwintered plum curculios, Conotrachelus nenuphar (Herbst), to odor-baited traps was evaluated from the beginning until nearly the end of emigration from overwintering sites in woods. We evaluated clear sticky Plexiglas panels and black pyramid traps placed close to woods adjacent to apple trees in an unsprayed section of an orchard. Traps were baited with aggregation pheromone (grandisoic acid) alone or in combination with one of six synthetic fruit volatiles (benzaldehvde, decyl aldehyde, E-2-hexenal, ethyl isovalerate, hexyl acetate, or limonene). Unbaited traps served as a control treatment. Plum curculio emigration from woods was divided into early-, mid-, and late-season periods based primarily on phenological stage of apple bud and fruit development (tight cluster to bloom, petal fall, and fruit set, respectively). During both early- and late season, panel and pyramid traps baited with benzaldehyde plus pheromone were significantly more attractive than any other traps (baited or unbaited), except panel traps baited with ethyl isovalerate plus pheromone in early season, which likewise captured significantly more adults than unbaited panel traps. During midseason, no lures were significantly attractive, possibly due to prevailing cool weather, unfavorable for adult activity. Over the entire season, panel or pyramid traps baited with benzaldehyde plus pheromone captured nearly six times as many plum curculios as unbaited traps of each type, whereas traps baited with pheromone alone captured about twice as many as unbaited traps of each type. We provide information on sex ratio, female maturity stage, and mating status, and several weather parameters associated with trap captures. We conclude that panel or pyramid traps, or a combination, baited with benzaldehyde plus pheromone placed at borders of plum curculio overwintering sites can be a valuable tool for monitoring the beginning, peak, and end of adult immigration into apple orchards.     

Using an Electronic Nose to Rapidly Assess Grandlure Content in Boll Weevil Pheromone Lures

Samples of pheromone lures used in boll weevil,Anthonomus grandis (Boheman),eradication programs are routinely analyzed by Gas Chromatography (GC) to ensure lures are adequately dosed with grandlure,the synthetic aggregation pheromone produced by male weevils.However,preparation of GC samples is tedious,time consuming,and requires a moderate level of experience.We examined the use of a commercially-available electronic nose (e-nose) for rapidly assessing the grandlure contents of lures.The e-nose was trained to recognize headspace collections of grandlure emitted from new lures and after lures were aged under field conditions for 4 d,7 d,10 d,and 14 d.Based on cross-validation of the training set,the e-nose was 82％accurate in discriminating among the different age classes of lures.Upon sampling headspace collections of pheromone from a different set of field-aged lures,the e-nose was ＜50％ accurate in discriminating 4 d,7 d,and 10 d aged lures from the other ageclasses of lures.However,the e-nose identified new and 14 d aged lure samples with 100％ accuracy.In light of these findings,e-nose technology shows considerable promise as an alternative approach for rapidly assessing the initial grandlure contents of lures used in boll weevil eradication programs.     

Mating disruption of Lasioderma serricorne (Coleoptera: Anobiidae) in stored product habitats using the synthetic pheromone serricornin

Cigarette beetles, Lasioderma serricorne (F.) (Coleoptera: Anobiidae), cause significant damage to the multibillion dollar food and tobacco industries worldwide each year. A non‐insecticidal alternative to manage L. serricorne is the application of mating disruption, in which high levels of synthetic sex pheromone are released to create an atmosphere that results in males failing to mate females, thereby causing population suppression or extinction. The reported work used synthetic serricornin, the predominant sex pheromone of L. serricorne, in mating disruption trials conducted in selected food‐ and feed‐processing facilities in South Carolina during 2010 and 2011. Mills subjected to mating disruption trials were monitored using oviposition cups filled with larval food and pheromone traps for males that contained monitoring lures. Immediately after deployment of mating disruption dispensers, trap captures declined significantly and indicated a reduction in population levels, that is, there was ‘trap shutdown’. A significant reduction was observed in numbers of adult beetles caught in the traps 8 weeks before and 8 weeks after treatment in both years. Beetle numbers from pheromone traps in untreated buildings remained at similar levels or increased after the time of mating disruption deployment in treated buildings. The numbers of adults that emerged from oviposition food cups were generally low and varied irregularly in treated and untreated buildings and were determined to be of little value for assessing treatment effects on reproduction. These initial field studies in the USA suggest that release of the synthetic sex pheromone of L. serricorne for mating disruption can significantly inhibit proper orientation behaviour of male L. serricorne to females and may lead to pest population decline from mating disruption.