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Most known click beetle (Coleoptera: Elateridae) sex pheromones have been identified from economically important European species. We hypothesized that pheromone components might be conserved between New and Old World species, and so tested blends of known pheromones in California and Washington states.Males of the endemic species Idolus californicus and Idolus columbianus (subfamily Elaterinae) were attracted to blends of neryl esters, many of which are known pheromones of related European species. Electroantennogram assays determined that antennae of male beetles responded strongly to two neryl esters, and in field bioassays, males of both species were specifically attracted to neryl hexanoate.Female I. californicus were found to produce both neryl hexanoate and neryl octanoate, and lures that contained neryl hexanoate alone or in blends attracted male beetles. Neryl octanoate was not attractive, and neither synergized nor antagonized attraction to neryl hexanoate.Males of Dalopius spp. also were captured in traps baited with lures containing neryl octanoate.Our results support the hypothesis that the neryl ester pheromone motif is conserved among taxonomically related European and North American elaterids in the tribe Elaterinae, which should aid in the identification of pheromones of pest species within the tribe. [ABSTRACT FROM AUTHOR]

Baits - fermented food products - are generally attractive to many types of insects, which makes it difficult to sort through non-target insects to monitor a pest species of interest. We test the hypothesis that a chemically simpler and more defined attractant developed for a target insect is more specific and attracts fewer non-target insects than a chemically more complex food-type bait. A four-component chemical lure isolated from a food bait and optimized for the spotted wing drosophila ( SWD), Drosophila suzukii ( Matsumura) ( Diptera: Drosophilidae), was compared to the original wine/vinegar bait to assess the relative responses of non-target insects. In several field experiments in Washington State, USA, it was shown that numbers of pest muscid flies, cutworm and armyworm moths, and pest yellowjackets were reduced in traps baited with the chemical lure compared to the wine/vinegar bait. In other field experiments in the states of Washington, Oregon, and New York, numbers of non-target drosophilid flies were also reduced in traps baited with the chemical lure relative to wine/vinegar bait. In Washington, numbers of Drosophila melanogaster Meigen and Drosophila obscura Fallen species groups and Drosophila immigrans Sturtevant were reduced in the chemical lure traps, whereas in New York, D. melanogaster and D. obscura species groups, D. immigrans, Drosophila putrida Sturtevant, Drosophila simulans Sturtevant, Drosophila tripunctata Loew, and Chymomyza spp. numbers were reduced. In Oregon, this same effect was observed with the D. melanogaster species group. Taken together, these results indicate that the four-component SWD chemical lure will be more selective for SWD compared to fermentation baits, which should reduce time and cost involved in trapping in order to monitor SWD. [ABSTRACT FROM AUTHOR]

BACKGROUND A mixture of wine and vinegar is more attractive than wine or vinegar to spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), and ethanol and acetic acid are considered key to that attractiveness. In addition to ethanol and acetic acid, 13 other wine and vinegar volatiles are antennally active to D. suzukii and might be involved in food finding. RESULTS Out of the 13 antennally active chemicals, acetoin, ethyl lactate and methionol increased fly response to a mixture of acetic acid and ethanol in field trapping experiments. A five-component blend of acetic acid, ethanol, acetoin, ethyl lactate and methionol was as attractive as the starting mixture of wine and vinegar in field tests conducted in the states of Oregon and Mississippi. Subtracting ethyl lactate from the five-component blend did not reduce the captures of flies in the trap. However, subtracting any other compound from the blend significantly reduced the numbers of flies captured. CONCLUSION These results indicate that acetic acid, ethanol, acetoin and methionol are key olfactory cues for D. suzukii when attracted to wine and vinegar, which may be food-finding behavior leading flies to fermenting fruit in nature. It is anticipated that this four-component blend can be used as a highly attractive chemical lure for detection and management of D. suzukii. Published 2013. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

We investigated the effect of mating on female attractiveness and male responsiveness in the potato psyllid, Bactericera (= Paratrioza) cockerelli ( Šulc) ( Hemiptera: Triozidae), a major pest of potato. Assays were designed to examine response by mated or virgin males to volatile odors produced by virgin or mated females. Mating induced a behavioral refractory period during which males were not attracted to females. The refractory period was shown to include a mating-induced lowering of male response to females, as well as a mating-induced lowering of female attractiveness. The refractory period was longer in females (at least 48 h) than in males (less than 24 h). Following a post-copulatory refractory period of 96 h, females were as attractive to males as virgin females. We also explored how rapidly spermatophores became depleted in females as a function of the amount of time following mating. The percent of females carrying spermatophores and the number of spermatophores per female decreased with the length of the female post-mating period, possibly due to the absorption by females of the spermatophores and their content. By 96 h following mating, spermatophores were not visible in the majority of females, thus the absence of spermatophores in females of this species should not be used as evidence of mating status. [ABSTRACT FROM AUTHOR]

The rate of entry by neonate larvae of the frugivorous codling moth, Cydia pomonella ( L.) ( Lepidoptera: Tortricidae), into fruit material was investigated. We used no-choice bioassays in climate-controlled rooms to assay larval entry across four host plant species (apple, pear, quince, walnut) and three varieties within a single fruit species (apple). Larvae successfully entering apples were reared to adulthood, and we collected tissue samples from apples which were successfully colonized in order to determine sucrose concentrations. This information was used to evaluate differences in adult moth size, development time, and pulp sucrose concentration due to apple variety. Four important findings emerged: (1) neonate larvae had the highest frequency of entry (86% of larvae) into apple fruits, compared with pear (78%), quince (56%), and walnut (32%); (2) the frequency of larval entry into immature apples differed across apple varieties, and larval entry rate was highest in variety Golden Delicious (72%), compared with Granny Smith (46%) and Red Delicious (64%); (3) on average, adult moths were larger and development times were shorter on the variety with the highest entry frequency (Golden Delicious); and (4) apple pulp sucrose concentrations were higher for Golden Delicious (17.5 μg mg−1) than for either Granny Smith (15.9 μg mg−1) or Red Delicious (15.1 μg mg−1) varieties, which correlates positively with entry and development data. We conclude that host fruit species and varietals within a species affect the entry rate of neonate codling moth larvae in no-choice assays. We hypothesize that larval development is influenced by mean sucrose concentrations or other phytochemical differences associated with host fruit varieties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Phenylacetaldehyde is a flower volatile and attractant for many nectar-seeking moths. Acetic acid is a microbial fermentation product that is present in insect sweet baits. It is weakly attractive to some moths and other insects, but can be additive or synergistic with other compounds to make more powerful insect lures. RESULTS: Acetic acid and phenylacetaldehyde presented together in traps made a stronger lure than either chemical alone for moths of the alfalfa looper Autographa californica (Speyer) and the armyworm Spodoptera albula (Walker). However, this combination of chemicals reduced captures of the cabbage looper moth Trichoplusia ni (Hübner), the silver Y moth Autographa gamma (L.), MacDunnoughia confusa (Stephens) and the soybean looper moth Chrysodeixis includens (Walker) by comparison with phenylacetaldehyde alone. CONCLUSION: These results indicate both positive and negative interactions of acetic acid, a sugar fermentation odor cue, and phenylacetaldehyde, a floral scent cue, in eliciting orientation responses of moths. This research provides a new two-component lure for the alfalfa looper A. californica and for the armyworm S. albula for potential use in pest management. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The potato psyllid, Bactericera (= Paratrioza) cockerelli (Šulc) (Hemiptera: Triozidae), is a major pest of potato. Studies were conducted to determine the age at which both males and females reach reproductive maturity and the effect of age and time of day on sex attraction. Adult B. cockerelli reach reproductive maturity within 48 h post-eclosion, with females being mature on the day of eclosion and males at 1 day post-eclosion. Oviposition generally began 2 days after mating but was delayed when females mated within 2 days post-eclosion. In laboratory olfactometer assays, the age of females used as odor sources and the age of males assayed to these odors did not affect sex attraction, with both younger (1-4-day-old) and older (8-10-day-old) males being attracted to females, regardless of female age (1-4-day-old or 8-10-day-old). Males assayed to live females at different times during the photophase (between 8:00 and 20:00 hours) were attracted to females between 11:00 and 17:00 hours, showing a temporal periodicity in sex attraction with B. cockerelli at least during the photophase. [ABSTRACT FROM AUTHOR]

Pear psylla, Cacopsylla pyricola (Förster) (Homoptera: Psyllidae), is a major pest of commercial pears in North America and Europe. Olfactometer trials have shown that males of both the summer and winter morphotype are attracted to female-infested host material. Additional work with the summer morphotype has shown that males are attracted to females even in the absence of the host plant, which is evidence that female C. pyricola produce a volatile sex attractant. Here, we describe similar results with the winterform, confirming for this morphotype that the female psylla rather than the infested host material is the source of the attractant. Male winterforms displayed attraction to odors from live females in the absence of the host plant, freshly killed females, and female whole body extracts. The female whole body extracts were at least as attractive as a comparable number of live females, suggesting that we were successful at extracting the components of the attractant with this procedure. All previous olfactometer trials with C. pyricola used the insect as the attractant source; the current study is the first to demonstrate that volatile chemicals isolated from the female insect were attractive to male conspecifics. Winterform males were also assayed to odors produced by conspecific males. We found that male psylla avoided volatile odors from live males, freshly killed males, or whole body extracts of males. To our knowledge, these results are the first indication that males of any member of the Psyllidae avoid odors associated with conspecific males. [ABSTRACT FROM AUTHOR]

Evaluation of combinations of flower odor compounds in the field revealed several compounds that were attractive or co-attractive with phenylacetaldehyde (PAA) to pest noctuid and pyralid moths. A number of moth species responded positively to the key floral odorant PAA. The floral odorants cis-jasmone, linalool, benzyl acetate, limonene, β-myrcene, methyl salicylate, and methyl 2-methoxybenzoate all increased captures of some moths when added to traps with PAA, but responses varied among the moth species that were trapped. For example, soybean looper moths, Pseudoplusia includens (Walker) (Lepidoptera: Noctuidae), most strongly responded to PAA + β-myrcene, but benzyl acetate, cis-jasmone, and limonene also increased captures of these moths when these compounds were used in traps along with PAA. Velvetbean caterpillar moths, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), responded most strongly to PAA + linalool, but β-myrcene, cis-jasmone, and limonene also increased captures of these moths in traps over numbers trapped with PAA. Positive responses to floral compound blends were also noted for golden looper [ Argyrogramma verruca (F.)], grass looper [ Mocis disseverans (Walker)], tobacco budworm [ Heliothis virescens (F.)], southern armyworm [ Spodoptera eridania (Stoll) (all Lepidoptera: Noctuidae)], and melonworm [ Diaphania hyalinata (L.) (Lepidoptera: Pyralidae)]. Overall, PAA + β-myrcene appeared to be the strongest floral compound combination for pest species trapped, compared to PAA or other compound blends. [ABSTRACT FROM AUTHOR]

Post-diapause winterform pear psylla, Cacopsylla pyricola (Förster) (Homoptera: Psyllidae), exhibit a highly clumped distribution in late winter in pear orchards. The behaviors leading to clumped distributions in this species are unknown, but could include aggregation for mating activities. Choice tests and assays with an olfactometer were done to test whether male psylla of the overwintering morphotype are attracted to pear shoots infested by post-diapause females and to shoots previously occupied by females. Paired choice tests in small arenas showed that males accumulated on pear shoots currently occupied or previously occupied by females if those shoots were paired with uninfested shoots or shoots previously occupied only by males. Assays with an olfactometer showed that males were attracted to volatile odors from female-infested or previously infested shoots. The exact source of the attractants (i.e., the female psylla, the pear shoot, or a combination of these sources) remains to be determined. [ABSTRACT FROM AUTHOR]

A companion study showed that male pear psylla, Cacopsylla pyricola (Förster) (Homoptera: Psyllidae) were attracted to volatiles from pear shoots infested with post-diapause females. The present study compared the behavioral response of males to diapause and post-diapause females. Assays were done using a Y-tube olfactometer. We collected male and female winterform psylla from pear orchards at regular intervals between late October (early diapause) and late February (post-diapause). Female-infested shoots were not attractive to males until the February samples, coinciding with ovarian maturation and onset of mating in the field. A second set of assays was done in which we manipulated diapause status in the laboratory either by exposing psylla to a long-day photoperiod or by treating insects with an insect growth regulator, fenoxycarb. In the photoperiod experiments, both short-day and long-day males preferentially selected long-day (post-diapause) females over short-day (diapause) females. Fenoxycarb-treated males preferred fenoxycarb-treated (post-diapause) females over untreated (diapause) females; untreated males showed no preferences. Results support observations made elsewhere that male winterform pear psylla perceive and are attracted to volatile odors associated with pear shoots infested with post-diapause females. [ABSTRACT FROM AUTHOR]

1 Chemical analyses of solvent extracts of pheromone glands of female western yellowstriped armyworm moths Spodoptera praefica (Grote) indicated the presence of (Z)-7-dodecenol (Z)-7-dodecenyl acetate (Z)-9-dodecenyl acetate (Z)-9-tetradecenyl acetate and (Z)-11-hexadecenyl acetate. 2 In field tests of combinations of these chemicals, small numbers of male S. praefica were captured in traps baited with (Z)-7-dodecenyl acetate. Numbers of males captured in traps were greatly increased in response to blends that included both (Z)-7-dodecenyl acetate with either (Z)-9-tetradecenyl acetate (Z)-9-dodecenyl acetate. The combination of (Z)-7-dodecenyl acetate and (Z)-9-tetradecenyl acetate provided the strongest sex attractant for use in trapping male S. praefica. 3 Males of the cabbage looper Trichoplusia ni (Hübner) were captured in traps baited with blends possessing (Z)-7-dodecenyl acetate, and were greatly reduced in traps baited with blends that included (Z)-7-dodecenol. 4 Multi-component blends that included (Z)-7-dodecenol attracted males of the alfalfa looper Autographa californica (Speyer). 5 Males of Peridroma saucia (Hübner) and Mamestra configurata Walker were captured in traps that included (Z)-9-tetradecenyl acetate with (Z)-11-hexadecenyl acetate. 6 These responses by other species of moths to S. praefica pheromone components and blends may still complicate the use of any lure for S. praefica. [ABSTRACT FROM AUTHOR]