B. A. Leonhardt

Separation and double-bond determination on nanogram quantities of aliphatic monounsaturated alcohols, aldehydes and carboxylic acid methyl esters

On fait reagir du dimethylolisulfure puis analyse par chromatographie en phase gazeuse/spectrometrie de masse

(E,Z)-2,13-octadecadien-1-ol acetate. A new pheromone structure for sesiid moths

Abstract (E,Z)-1,13-Octadecadien-1-ol acetate was identified from ovipositor extracts of the grape root borer and was shown to attract males of the species.

An unusual lepidopteran sex pheromone system in the bagworm moth.

The female sex pheromone of the bagworm moth is (R)-1-methylbutyl decanoate. The antipode is biologically inactive and it neither enhances nor detracts from the potency of the R enantiomer. Unlike other moths for which female pheromones have been identified, the female secretes the pheromone from glands on her thorax and it is disseminated from hair that is shed from her body.

Methylcyclopentanoid Monoterpenes Mediate Interactions Among Insect Herbivores

Beetles secrete an array of chemicals generally believed to mitigate attack by predators. Methylcyclopentanoid monoterpenes secreted by larvae of the willow leaf beetle, Plagiodera versicolora, deter feeding by conspecific adults. Furthermore, the secretion elicits a strong repugnancy response in larvae of another willow herbivore, Nymphalis antiopa. Leaves bearing beetle larvae are less likely than leaves not bearing beetles to be frequented and consumed by Nymphalis larvae. Predator defense may not be the sole function of glandular secretions produced by herbivorous insects; secretions may also mediate interactions among herbivores that use a common resource.

Female sex pheromone of the melonworm,Diaphania hyalinata (Lepidoptera: Pyralidae), and analysis of male responses to pheromone in a flight tunnel

Ten C16 chain-length compounds were identified from heptane extracts of ovipositors of female melonworm,Diaphania hyalinata (L.). The major constituents of the extracts were (E)-11-hexadecenal and (E,E)-10,12-hexadecadienal [(E,E)-10,12–16:Ald] and the alcohols and acetates of these olefins were found in trace amounts (<2%). Extracts also contained traces of (E,Z)- and (Z,Z)-10,12-16:Ald, hexadecanal, and 1-hexadecanol. Analysis of the behavioral responses of males to synthetic mixtures of these compounds and responses to ovipositor extracts in a flight tunnel showed that a synthetic mixture of the 10 compounds elicited a behavioral repertoire from males that was indistinguishable from that elicited by ovipositor extract. Flight tunnel studies also indicated that six of the 10 compounds probably represent the essential components of the females sex pheromone.

Female sex pheromone of the pickleworm, Diaphania nitidalis (Lepidoptera: Pyralidae).

Heptane extracts of the ovipositors from pickleworm adults (Diaphania nitidalis) were found to contain (E)-11-hexadecenal along with proportionally smaller amounts of (Z)-11-hexadecenal, (E)- and (Z)-11-hexadecen-1-ol, hexadecanol, hexadecanal, and a trace amount of (E,Z)-10,12-hexadecadienal. Assays conducted in a flight tunnel and in the field showed that a synthetic mixture of the five unsaturated compounds elicited behavioral responses from pickleworm males that were indistinguishable from those elicited by extracts of the female or by mate-calling females. When any component was deleted from the set of five unsaturated compounds, the intensity and extent of male responses to the resulting mixtures were significantly attenuated. The female sex pheromone of the pickleworm resembles the pheromone of a congeneric species,D. hyalinata, but bioassays indicated that (E,E)-10,12-hexadecadienal, produced byD. hyalinata but not by the pickleworm, plays a role in pheromonal specificity.

Improved controlled-release formulations for a new trap design for male Mediterranean fruit flies : The C&C trap

The Mediterranean fruit fly, Ceratitis capitata, is a major pest of fruits and vegetables in the world. With the help of an extensive trapping program, the continental United States has remained free of established medfly populations. In an effort to increase trapping efficiency, controlled-release polymeric panels with trimedlure and ceralure were developed in conjunction with the development of a new trap, the C&C trap. This study contrasts the effectiveness of different panel formulations with the standard trimedlure polymeric plug and describes the use of the panels in the C&C trap. Field tests in Hawaii using released sterile flies showed consistently higher male medfly catches with panels in C&C traps than with the standard trimedlure polymeric plug in Jackson traps.

Synthesis of attractants for oriental fruit flyDacus dorsalis Hendel using a catalytic organocopper coupling reaction

A general synthetic approach to various catechol derivatives was developed using a copper-catalyzed cross-coupling reaction of 1,2-dimethoxy-4-brornomethyl, 1-ethoxy-2-methoxy-4-bromomethyl- and 2-ethoxy-1-methoxy-4-bromomethylbenzenes with Grignard reagents. Dilithium tetrachlorocuprate was an acceptable catalyst in the dimethoxy series, whereas copper(I) iodide in THF-HMPA was a superior catalyst in all cases due to decreased side reactions, i.e., reduction and reductive coupling. Methyl-substituted analogs of methyl eugenol, a potent attractant of Oriental fruit fly,Dacus dorsalis Hendel, were synthesized by this method and evaluated for attractancy in field tests.

Comparison of Ceralure and Trimedlure Controlled-Release Formulations for Male Mediterranean Fruit Flies in C&C Traps

Ceralure or trimedlure polymeric TNO panels in C&C traps were compared for attractancy by the capture of male Mediterranean fruit flies, Ceratitis capitata (Wiedemann). This study contrasts the effectiveness of ceralure with trimedlure, the former of which is an iodo-analog of trimedlure. Field tests in Hawaii with released flies showed that the active ceralure B1 isomer in a commercial mixture of ceralure isomers consistently caught as many male flies as active trimedlure C isomer in a commercial mixture of trimedlure isomers at one-half the molar quantity of trimedlure C. These panels caught 6.4 and 5.2 times, for ceralure and trimedlure, respectively, more than the standard 2 g trimedlure AgriSense aged plug over a 26-week period. The persistence of ceralure is demonstrated by residual analyses of aged panels that revealed the presence of 2.75 times more ceralure than trimedlure in panels after 130 days of field exposure.

Capillary gas chromatography method for the analysis of the trans isomers of ceralure, a medfly attractant

Abstract A capillary GC method has been developed to analyze laboratory or commercial samples of the medfly attractant ceralure [ethyl 4- (and 5-)iodo-trans-2-methylcyclohexane-1-carboxylate]. The method utilizes a specially prepared fused-silica column with a bonded phenyl-methyl polysiloxane liquid phase. Baseline separation was achieved for three of the four trans-ceralure isomers. Difficulties encountered with other columns investigated are also discussed.