Isomers of [11,12-3H2]-11-tetradecenyl acetate (57 Ci/mM) were synthesized. Behavioral assay of the two compounds using Z- and E-type European corn borer (ECB) males showed that introduction of tritons into the double bond of the pheromone caused a significant isotope effect in the E-type ECB but not in the Z-type ECB. Measurements of tritium associated with the male antennae after a 3-min exposure showed that radioactivity equivalent to 10−7 mol pheromone was adsorbed onto male antennae. Time-course in vivo metabolic studies with picogram amounts of compound applied topically to antennae of E- and Z-type males and Z-type females showed that they metabolized pheromone similarly but females degraded pheromone more slowly than males. Pheromone was hydrolyzed, and the only other major radiolabeled metabolite observed by combined high-pressure liquid chromatography-radiodetection was tritiated water. Capillary gas chromatography and radiomonitoring permitted detection of a trace amount of 11-tetradecenoic acid, which indicated alcohol oxidase activity is associated with the antennae. Evidence shows that clearing of pheromone from the ECB male antennae involves hydrolysis and oxidation of the alcohol to fatty acid, which in turn is degraded, probably via β-oxidation, to carbon dioxide and water.

The regulation of post-mating decline of sex-pheromone in the gypsy moth, Lymantria dispar, was studied. An initial, transient suppression of pheromone production was found to be caused by the introduction of male genitalia into the bursa copulatrix, which results in mechanical pressure being transmitted via innervation of the bursa. However, if sperm was not transferred during mating, pheromone production resumed and females returned to calling behavior. Permanent suppression of pheromone production resulted from an adequate supply of sperm in the spermatheca and could be prevented in females from which spermatheca was removed. During the initial period of suppression of pheromone production females were sexually receptive and could remate. They became nonreceptive only when pheromone production was terminated and oviposition begun.

Females of gypsy moth, Lymantria dispar, produce a sex pheromone, cis-2-decyl-3-(5-methylhexyl) oxirane, or disparlure, to attract their mates. After successful mating the females become nonreceptive to other males and commence oviposition. In Heliothis zea, it was reported that mating caused a rapid decline in the pheromone titer of the females but that the titer increased again on subsequent nights following the night of mating (Raina et al., 1986). The present study was initiated to investigate the fate of the sex pheromone in mated gypsy moth females and to determine the mechanism through which the switch from virgin to mated behavior operated.

After mating, females of the gypsy moth, Lymantria dispar (Lepidoptera: Lymantriidae) stop producing sex pheromone, become sexually non-receptive, and commence oviposition. These post-mating behaviours were observed to occur spontaneously in senescent virgin females. Strong correlation was shown betweer decrease in sex pheromone, initiation of oviposition and loss of sexual receptivity in ageing virgin females. Thus, the mechanism which induces the change from virgin to mated behaviour appears to reside within the female, although it would be normally triggered in younger females by signals associated with mating. Removal of the spermatheca or bursa copulatrix from virgin females did not prevent the appearance of mated-like behaviour as the females aged.

The biological activity of analogs of the pheromone components of the European corn borer,Ostrinia nubilalis, (Z)- and (E)-11-tetradecen1-ol acetate, in which modifications were made in the terminal alkyl portion were studied in the three pheromonal types of the insect. European corn borer males respond to pheromonal stimuli at three levels of behavioral activity, i.e., short-range sexual stimulation, activation in the flight tunnel, and response in the field. Structural requirements for elicitation of response at these levels were found to be increasingly restrictive, respectively. Flighttunnel activity was induced only by compounds that had a total chain length of 13 or 14 carbons and in which branching at carbon 13 was limited to one methyl group or a cyclopropyl group. Three new analogs were active in the flight tunnel, viz., (E and (Z)-13-methyl-11-tetradecen-1-ol acetate and (Z)-12-cyclopropyl-11-dodecen-1-ol acetate. The cyclopropyl analog was the most active analog against theZZ type of the European corn borer. TheE isomer, however, was pheromonally inactive in theEE type and was shown to be a pheromone antagonist. This dissimilarity is most likely due to differences in structure of the receptors in the European corn borer strains. Analogs that were biologically active against the European corn borer were tested against the redbanded leafroller,Argyrotaenia velutinana, which also uses (Z)- and (E)-11-tetradecen-1-ol acetate as part of its pheromone. Results showed that the redbanded leafroller pheromone acceptor system is different from that of the European com borer; marginal behavioral response was elicited by only one of the new analogs. Thus, although both species use 11-tetradecen-1-ol acetate isomers as their pheromone, the mechanisms by which they are perceived are different.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOptical isomers of .alpha.-copaene derived from several plant sourcesMartin Jacobson, Edward C. Uebel, William R. Lusby, and Rolland M. WatersCite this: J. Agric. Food Chem. 1987, 35, 5, 798–800Publication Date (Print):September 1, 1987Publication History Published online1 May 2002Published inissue 1 September 1987https://pubs.acs.org/doi/10.1021/jf00077a038https://doi.org/10.1021/jf00077a038research-articleACS PublicationsRequest reuse permissionsArticle Views301Altmetric-Citations26LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Margosine-0®, a commercial preparation of neem seed extract, was tested for its effects as a toxicant, growth inhibitor, or repellent against six species of cockroaches —Blatta orientalis L.,Blattella germanica (L.),Byrsotria fumigata Guérin-Méneville,Gromphadorhina portentosa (Schaum),Periplaneta americana (L.), andSupella longipalpa (F.) (Orthoptera: Blaberidae, Blattidae, and Blattel-lidae). Last-instar nymphs of these species fed Lab-Chow® pellets impregnated with neem extract at a rate of 0.5 ml/pellet showed increased mortality and retarded development. All lst-instar nymphs ofB, orientalis, B. germanica andS. longipalpa died after consuming treated Lab-Chow pellets. Topical application of 2 μl of Margosine-0 to the abdomens of last-instarB. orientalis nymphs, as well as injection of 0.5 μl, resulted in reduction of growth and increased mortality. Placing lst-instarB. orientalis nymphs on a surface treated with the neem extract had no notable effect. In a choice test,P. americana adults immediately preferred the pellets treated with 0.5 ml of neem extract, but pint cardboard cartons treated with 1.5 ml extract repelled them.

Abstract A commercial preparation of neem extract, Margosine‐O, was tested for its antifeedant activity against 3 adult orthopteran insects, Carolina grasshoppers, walkingsticks, and field crickets. Twenty μ1 of 1, 5, 10, 20, and 50% solutions of extract were applied to 2 × 2‐cm corn‐leaf squares in tests with the grasshoppers and crickets, and to 2 × 2‐cm white oak‐leaf squares in tests with walkingsticks. Concentrations of 10, 5, and 5%, respectively were necessary to produce a significant reduction in feeding on the mixed sexes of Carolina grasshoppers, female walkingsticks, and female crickets, respectively. The levels of neem extract necessary to inhibit feeding by these 3 species were many times greater than the concentrations reported to be effective for inhibiting feeding in the desert locust and African migratory locusts.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTIsolation and identification of novel lactones from male Mexican fruit fliesJerry B. Stokes, Edward C. Uebel, John D. Warthen Jr., Martin Jacobson, Judith L. Flippen-Anderson, Richard Gilardi, Leonard M. Spishakoff, and Kenneth R. WilzerCite this: J. Agric. Food Chem. 1983, 31, 6, 1162–1167Publication Date (Print):November 1, 1983Publication History Published online1 May 2002Published inissue 1 November 1983https://pubs.acs.org/doi/10.1021/jf00120a007https://doi.org/10.1021/jf00120a007research-articleACS PublicationsRequest reuse permissionsArticle Views115Altmetric-Citations31LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

A sex pheromone for adult male oriental cockroaches Blatta orientalis was isolated from the faeces of adult virgin female oriental cockroaches. It elicited a sexual response at 10 pg and 1 ng with B. orientalis and Periplaneta americana adult males, respectively. The site of production appers to be the crop, oesophagus, and proventriculus. Electroantennogram responses of male antennae toward the isolated pheromone were greater than those of the female antennae. The adult male oriental cockroach also responded to the American cockroach sex pheromone. The isolated pheromone with a mol. wt of 232 may be similar to one of the components of the American cockroach sex pheromone.

Thirty‐nine local plants of Maryland were collected, ground, and extracted with two solvents. The extracts were incorporated into an artificial diet and tested for antifeedant activity vs. a control against fall armyworm first‐instar larvae, Spodoptera frugiperda (J. E. Smith). Several extracts resulted in larvae that weighed less than 10% of the average weight of the control larvae.

In laboratory and greenhouse tests, suspensions containing low concentrations of azadirachtin and salannin, compounds isolated from ethanolic extracts of neem seeds, Azadirachta indica A. Juss., possessed activity as feeding deterrents against the striped cucumber beetle, Acalymma vittatum (F.), and the spotted cucumber beetle, Diabrotica undecimpunctata howardi Barber. The chemicals were particularly active against the striped cucumber beetle, the more serious pest of muskmelons. In greenhouse and seed bed tests, the protection provided by azadirachtin against the striped cucumber beetle was not as great as the protection provided by carbaryyl.

This paper reports on the chemical constituents of the cuticular lipids of a phasmatid with special emphasis on differences in composition between the sexes. Wax esters that were more abundant in adult females than in males included combinations of straight-chain primary alcohols of 24, 26, and 28 carbons and straight-chain acids of 16, 18, 22, and 24 carbons. Hydrocarbons including n-alkanes, 3-methylalkanes, internally-branched monomethylalkanes, and dimethylalkanes were also identified.

Cucumber beetles are destructive pests of melons in the Midwest both because of their feeding and transmission of bacterial wilt disease. Because an effective antifeedant would be an ideal control measure, more than 350 materials of biological origin have been screened against striped cucumber beetle. Such materials as neem derivatives, neriifolin, -tung, and napthoquinones appear promising and will be tested more extensively.

Adult male field crickets,Gryllus pennsylvanicus Burmeister, have more unsaturated cuticular hydrocarbons than adult females, and each has more unsaturates than last-instar male and female nymphs. The 2 most abundant unsaturated hydrocarbons from each adult were (Z)-7-nonacosene and (Z,Z)-6,22-nonacosadiene. Last-instar male nymphal field crickets,Nemobius fasciatus (De Geer), were almost devoid of cuticular alkenes compared to last instar female nymphs and adult males and females. The major unsaturated hydrocarbon from each was (Z,Z)-6,9-pentacosadiene.

Cuticular lipids of adult male house crickets, Acheta domesticus (L.), contained greater amounts of 37-carbon dienes, 37-carbon monoenes, and 39-carbon dienes than did adult female and male nymphs. Although each group of these unsaturated hydrocarbons was a mixture, the major component of each was identified as (Z,Z)-7,25-heptatriacontadiene, (Z)-2-methyl-24-hexatriacontene and (Z,Z)-9,25-nonatriacontadiene, respectively.