E. Dunkelblum's research while affiliated with Agricultural Research Organization ARO and other places

Publications (103)

Article
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The review describes the history of pheromone research in Israel in 1975–2015. The research focused on sex pheromones of moths that were important agricultural pests. Identification, synthesis and field application of sex pheromones was performed. Synthetic procedures of several known sex pheromones were developed. Monitoring and control of key pes...
Article
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The lesser date moth (LDM) Batrachedra amydraula is a significant pest of date palm fruits. Previously, detection and monitoring of the pest was inaccurate due to high costs of sampling with lifting machines. We report a practical system for detection and monitoring of LDM based on pheromone traps and relevant models. Dose–response experiments with...
Article
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The diel periodicity of sex pheromone release was monitored in two mealybug species, Planococcus citri and Planococcus ficus (Hemiptera; Pseudococcidae), using sequential SPME/GCMS analysis. A maximal release of 2 ng/h pheromone by 9–12-day-old P. citri females occurred 1–2 h before the beginning of photophase. The highest release of pheromone by P...
Article
The greater date moth (GDM), Aphomia sabella Hampson (Lepidoptera: Pyralidae: Galleriinae), is a serious pest of date palms, Phoenix dactylifera. The release of volatiles from both males and females was investigated using sequential SPME/GC/MS analysis. Males release a complex mixture of compounds in a circadian rhythm during the night between 03:0...
Article
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The yellow-legged clearwing (YLC) Synanthedon vespiformis (Lepidoptera: Sesiidae) occurs in the Mediterranean and central Europe. It is polyphagous, boring into the woody parts of broadleaf species including forest trees as well as various Rosaceae species. S. vespiformis has been reported as an economically important pest causing severe injury to...
Article
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The yellow-legged clearwing (YLC) Synanthedon vespiformis (Lepidoptera:Sesiidae) occurs in the Mediterranean and central Europe. It is polyphagous pest, boring into the woody parts of broadleaf species including forest trees as well as various Rosaceae species. YLC has been reported as an economically important pest causing severe injury to stone f...
Article
Capillary gas chromatography indicated the presence of (Z)-7-dodecenyl alcohol and (Z)-7-dodecenyl acetate in the abdominal tip extracts of female Cornutiplusia circumflexa (L.) (Lepidoptera: Noctuidae: Plusiinae) moths. Gas chromatography combined with mass spectrometry and dimethyl disulfide derivatization confirmed the structure of these two pri...
Article
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The vine mealybug (VM) females collected in Israel produce two sex pheromone compounds: lavandulyl senecioate (LS) and (S)-lavandulyl isovalerate (LI). The males display ambiguous behavior to LI: repulsion in the vineyard and attraction of laboratory-reared males. We addressed the question of individual male behavior, i.e., do males respond to both...
Article
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The vine mealybug (VM), Planococcus ficus (Signoret), is a worldwide pest and affects mainly grapevine and figs. In Israel, (S)-lavandulyl senecioate [(S)-LS] and (S)-lavandulyl isovalerate [(S)-LI] were identified from VM reared for several generations on potato sprouts, when compared with the identification of only (S)-LS from feral females. Race...
Article
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Israeli vine growers have been reluctant to adopt the mating disruption technique for control of the European vine moth, Lobesia botrana Den. & Schiff. Since the chemically controlled honeydew moth, Cryptoblabes gnidiella Mill., coexists with the European vine moth, growers have maintained that the use of mating disruption would fail to bring about...
Article
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During the last decade injury caused by caterpillars (Lepidoptera) boring into the roots, and root collar of stone fruit trees (Prunus spp.) has been observed in many plantations in Israel. Damage has been caused mainly to nectarine, peach and almond orchards. The infestation was associated with infestation by Agrobacterium tumefaciens. In heavily...
Article
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The attraction of several adult predators, genera Elatophilus, Hemerobius and Sympherobius, to the sex pheromones of pine bast scales, Matsucoccus Cockerell, has already been demonstrated. Here, the hypothesis that the larvae of these predators are similarly attracted to the host prey sex pheromone is tested. The response of predators was tested in...
Article
(R)- and (S)-lavandulol and their esters are important compounds in perfumery and have recently become significant in pheromone research. (R)-Lavandulol and its esters, as well as the esters of (S)-lavandulol have been identified as sex and aggregation pheromones in two mealybugs, in thrips and in weevils. We report a convenient resolution of racem...
Article
Two closely related plusiinae moths, Autographa gamma Linnaeus and Cornutiplusia circumflexa Linnaeus, are sympatric in Israel. Both species use identical sex pheromone components but in different ratios, and do not attempt to mate with each other. In addition to the effective reproductive separation by their sex pheromones, the sexual behavior of...
Article
The enantiomers of (E)- and (Z)-sabinene hydrate and of (E)- and (Z)-sabinene hydrate acetate from extracts of Origanum ramonense Danin, O. dayi Post, O. majorana L., O. vulgare L. ssp. vulgare and O. syriacum L. ssp. syriacum were analysed by GC–MS with chiral and non-chiral capillary columns. The order of elution, the enantiomeric ratios and rela...
Article
Full-text available
The reluctance of Israeli vine growers to adopt the mating disruption technique to control the moth Lobesia botrana Den. & Schiff. has been attributed to the high cost of this method compared with that of traditional insecticide control. In this study, we tested the possibility of reducing the cost, first by testing different pheromone formulations...
Article
The kairomonal response of potential predators of pine bast scales Matsucoccus Cockerell was investigated using traps baited with female sex pheromones of Matsucoccus josephi Bodenheimer and Harpaz, Matsucoccus feytaudi Ducasse, and Matsucoccus matsumurae Kuwana. In addition to the attraction of conspecific males and a weak cross attraction of cong...
Article
A simple synthesis of the pheromone of the citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae), has been developed. Various factors affecting capture of males have been assessed to optimize the trap design and to develop a lure with high efficacy and longevity. Male capture was the same with the racemic and chiral pheromone; tech...
Article
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Stereoisomers of 4-methyl-3-heptanol are major components of aggregation pheromones of bark beetles and trail pheromones of ants. Recently, (3S,4S)-4-methyl-3-heptanol (I) has been tentatively identified as the main component of the aggregation pheromone of the almond bark beetle, Scolytus amygdali (Coleoptera: Scolytidae). The four stereoisomers o...
Article
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The biological activity of the Matsucoccus spp. sex pheromones and diene modified analogs has been tested in forests of Israel and Portugal in order to explore the structure-activity relationship of the pine bast scale pheromone/kairomone system. The response of the adult predatory bugs, Elatophilus hebraicus and E. crassicornis and of the brown la...
Article
Two pheromonal components were detected in airborne collections from the vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) mass-reared on potato sprouts. The compounds were identified as (S)-lavandulyl senecioate (I) and (S)-lavandulyl isovalerate (II) by GC and GC-MS by comparison with synthetic standards. Chiral GC analysis o...
Article
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Aliphatic secondary alcohols are components of several aggregation pheromones of important beetle and weevil pests. Some of these pheromones are used frequently for the monitoring and mass trapping of the relevant insects. We encountered severe difficulties in direct GC quantitative analysis of these compounds. Therefore, we developed a simple GC a...
Conference Paper
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Significant increases in up a armigera in a wind-tunnel were obtained with air entrained headspace samples of African marigold, Tagetes erecta, flowers (P=0.014), and sweet pea, Lathyrus odoratus, flowers (P=0.047). Identification of the compounds contained in the Porapak Q extracts was done by GC-MS. Direct EAG was used to screen for the most elec...
Article
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The citrus mealybug, is a cosmopolitan pest and affects many crops. The female sex pheromone has been identified by Bierl-Leonhardt et al., in 1981 as (+)-(1 R)-cis-2,2-dimethyl-3- isopropenylcyclobutanemethanol acetate 1. Several groups including our team have synthesized the pheromone. A number of analogs have also been prepared in order to study...
Article
New syntheses were achieved to secure matsuone (1), the pheromone of the pine scale Matsucoccus matsumurae, that of M. feytaudi (2), and that of M. josephi (3). Five analogues (4-8) of 1, 2, and 3 were synthesized and their bioactivities studied. The pheromone analogue 7 showed relatively strong pheromonal activity toward M. josephi, while it was i...
Article
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It has been demonstrated previously that the sex pheromone of the Israeli pine bast scale, Matsucoccus josephi, (2E,5R,6E,8E)-5,7-dimethyl2,6,8-decatrien-4-one (1) is also a potent kairomone of the scale insect's predator Elatophilus hebraicus. Surprisingly, the sex pheromones of M. feytaudi (2) and M. matsumurae (3) also attract E. hebraicus. Thes...
Article
The effect of density of the Shin-Etsu twist-tie rope pheromone formulation (PBW rope L®) on mating of female pink bollworm, Pectinophora gossypiella(Saunders) was tested in Israel. The success of mating disruption was evaluated during 1997 by the mating table technique, comparing the percentage of mating of virgin sentinel females in pheromone-tre...
Article
Three aldehydes. (Z)-11-hexadecenal (Z11–16:Ald), (Z)-7-hexadecenal (Z7–16:Ald) and (Z)-13-octadecenal (Z13–18:Ald), in a ratio of 74:23:3 are female-produced sex pheromone components of the pyralid moth, Diatraea considerata (Heinrich). Compounds extracted from pheromone glands were identified by coupled gas chromatographic-electroantennographic d...
Article
Different Shin-Etsu twist-tie rope formulations, containing either the cotton bollworm, Helicoverpa armigera (Hübner) pheromone or pink bollworm, Pectinophora gossypiella (Saunders) pheromone, or both, in the same rope, were tested in Israel for mating disruption. The success of mating disruption was evaluated by the mating table technique, compari...
Chapter
Pheromone biosynthesis activating neuropeptides (PBANs) (Raina and Klun 1984) are C-terminally amidated neuropeptides that regulate sex pheromone biosynthesis in moths. To date, four different PBAN molecules were isolated and their primary structures have been determined. The first PBAN molecule (33 amino acids) was isolated from Helicoverpa zea (H...
Chapter
Insect neuropeptides play a key role in the regulation of a variety of physiological functions such as embryonic and post-embryonic development, homeostasis, osmoregulation, migration, oviposition and mating (for review, see Menn and Borkovec, 1989; Kelly et al., 1994). In recent years, improvements of biochemical and chemical techniques have facil...
Article
The predator Elatophilus hebraicus is closely associated with its prey, the pine bast scale, Matsucoccus josephi, and utilizes the M. josephi sex pheromone as a kairomone. Kairomonal activity of E. hebraicus was studied by GC-EAD and field bioassays. The sex pheromone of M. josephi [2E,5R,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one [(R)-E-M.j.] elici...
Article
Control of the codling moth,Cydia pomonella (L.) (Lepidoptera: Tortricidae), by pheromone-mediated mating disruption, was studied in Israel using two types of dispensers: Shin-Etsu twist-tie (normal and long-life) and TNO matrix formulation (square wafers). Factors affecting mating disruption: initial pest population density, timing of the pheromon...
Article
The absolute configuration of the sex pheromone of the Israeli pine bast scale,Matsucoccus josephi, was determined as (2E,5R,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one, designated here asR-E with 10% (2E,5S,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one, designated asS-E. The chirality of the quantitatively minorZ isomer was (2E,5R,6Z,8E)-5,7-dimethyl-2,...
Article
The active component of the sex pheromone ofMatsucoccus josephi is (2E,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one; the chemical is also a powerful kairomone of adult males and females of the bugElatophilus hebraicus the principal predator ofM. josephi. The presence of theZ isomer (2E,6Z,8E)-5,7-dimethyl-2,6,8-decatrien-4-one does not interfere with...
Article
A structure-activity relationship study of Hez-PBAN was performed with respect to its pheromonotropic activity, using Heliothis peltigera as the test animal. The activity of N- and C-terminally derived sequences was examined in a time- and dose-dependent mode. Using a variety of Hez-PBAN-derived fragments at two doses (1 and 10 pmol) and at differe...
Article
The effects of dispenser type, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping efficiency of males of the European vine moth,Lobesia botrana Den. et Schiff. (Lepidoptera: Tortricidae), were investigated. LB Pherocon caps and locally manufactured septa were equally effective in attracting males to traps. W...
Article
The effects of ratio between sex pheromone components, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping efficiency of males of the peach twig borer,Anarsia lineatella Zeller (Lepidoptera: Gelechiidae), were investigated. To attract males, the optimal ratio between pheromonal components in a binary blend co...
Article
The effects of dispenser type, dispenser aging in the field, pheromone dose in the dispenser and trap type on trapping efficiency of codling moth,Cydia pomonella (L.), males were investigated in Israel. An Israeli-manufactured rubber septum was significantly better than the CM Pherocon cap in attracting males to a Pherocon 1C cap trap or an IPS tra...
Article
The effects of pheromone components, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping efficiency of males of the honeydew moth,Cryptoblabes gnidiella (Mill.) (Lepidoptera: Pyralidae), were investigated. At dosages of 2 or 0.2 mg, a binary blend containing (Z)-11-hexadecenal (Z11–16: Aid) and (Z)-13-octadec...
Article
We report the first synthesis of the two components of the female sex pheromone of Matsucoccus josephi (2E,4E,8E)-4,6-dimethyl-2,4,8-decatrien-7-one (1) and (2E,4Z,8E)-4,6-dimethyl-2,4,8-decatrien-7-one (2) utilizing the Reformatzky and Wittig reactions as key steps. A mixture of 1 and 2 and the separate isomers were bioassayed in a pine forest ind...
Article
(2E,4E,8E)-4,6-dimethyl-2,4,8-decatrien-7-one (I) and (2E,4Z,8E)-4,6-dimethyl-2,4,8-decatrien-7-one (II), in an approximate ratio of 75:25, have been identified as the female sex pheromone components of Matsucoccus josephi. The structure ofI and II was determined by mass spectrometric and infrared techniques and microreactions.
Article
The female sex pheromones of four sympatric Plusiinae species, Autographa gamma, Chrysodeixis chalcites, Cornutiplusia circumflexa, and Trichoplusia ni were investigated in Israel. The research concentrated on the behavioral reproductive isolation regulated by their sex pheromones. The chemical composition of the four sex pheromones was determined...
Article
Sex pheromone production in female moths is controlled by a cerebral factor termed pheromone biosynthesis activating neuropeptide (PBAN). Our understanding of the sequence of events common to the neuroendocrine process of PBAN, namely, its biosynthesis, secretion, transport, biological activity, and degradation, is very limited. Moreover, some of t...
Article
Israeli contributions to the development of monitoring and mating suppression systems for cotton pests via the use of sex pheromones are described. These include identification of pheromones, development of dispensers and traps, assessment of pheromone traps as a monitoring device, and the use of pheromones for mating disruption. In Spodoptera litt...
Article
The composition of theAutographa gamma sex pheromone was reexamined and only (Z)-7-dodecenyl acetate and (Z)-7-dodecenol were identified by capillary GC, GC-MS, and dimethyl disulfide derivatization and subsequent GC-MS analysis. The fatty acid content of the pheromone glands was also studied, and a series of saturated and unsaturated acids was ide...
Article
Shin Etsu twist-tie ropes containing the spiny bollworm (Earias insulana(Boisduval)) pheromone were tested for mating disruption in a cotton field in Israel during 1991. Two applications of the Shin Etsu rope formulation (1000 ropes/ha), containing 50 mg pheromone per rope, effectively disrupted mating of E. insulana, reduced damage to cotton bolls...
Article
Field tests were carried out to determine whether pheromone traps, baited with (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:Ac) impregnated in rubber septa (Maavit, Israel), could provide a reliable tool for monitoring the raisin moth,Cadra figulilella (Gregson), in date palm plantations. No significant differences were detected between captures o...
Article
Analysis of ovipositor washings from virgin femaleHelicoverpa assulta (Guenée) (Lepidoptere: Noctuidae) from Korea by gas chromatography (GC) linked to electroantennography and GC linked to mass spectrometry resulted in the identification of nine compounds, hexadecanal, (Z)-9-hexadecenal, (Z)-11-hexadecenal, hexadecyl acetate, (Z)-9-hexadecenyl ace...
Article
The sexual behaviour of Heliothis peltigera (Denis & Schiffermüller) was studied in the laboratory. Calling activity was very low during the first five hours of scotophase and then increased sharply, particularly in six-to eight-day old females. Peak activity was observed, in all ages tested, between eight and nine hours into scotophase. Calling in...
Article
This study describes the preparation and characterization of a highly specific antiserum to Helicoverpa zea pheromone biosynthesis activating neuropeptide (Hez-PBAN), and the use of this antiserum, in an enzyme linked immunosorbent assay (ELISA), to determine: a) the content of endogenous PBAN in head extracts of male and female Heliothis peltigera...
Article
The activity of synthetic Heliothis zea PBAN (Hez-PBAN) and four shorter peptides on the sex pheromone biosynthesis in Heliothis peltigera was investigated in order to characterize their biological potency, and to determine the structure-activity relationship. Hez-PBAN (PBAN 1–33) is very potent and stimulates sex pheromone biosynthesis at the pico...
Article
Six compounds were identified from gland extracts of the cotton bollworm, Heliothis armigera(Hubner): (Z)-11-hexadecenal (Z11-16:Ald), (Z)-9-hexa-decenal (Z9-16:Ald), hexadecanal, (Z)-11-hexadecenol (Z11-16:OH), (Z)-7-hexadecenal (Z7-16:Ald), and (Z)-9-tetradecenal (Z9-14:Ald). Each of the compounds that were identified was examined for its ability...
Article
The daily emergence patterns ofMatsucoccus josephi adults and third-instar male larvae raised on artificially infested saplings ofPinus halepensis were determined. A single peak of emergence was found for adult males between 0300 and 0500 hr. Adult females emerged throughout the day, with maximum emergence between 0500 and 0700 hr. Two daily emerge...
Chapter
The purpose of our study was to characterize the biological activity of PBAN (Pheromone Biosynthesis Activating Neuropeptide, Raina and Klun, 1984; Raina et al., 1989), and to study its mode of action on the biosynthetic process in the pheromone gland of two moths species: Heliothis peltigera and Chrysodeixis chalcites.
Article
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A series of C11–C14 alcohols, varying in the number, position and geometry of double bonds, was applied topically to the sex pheromone glands of the tomato looper, Chrysodeixis chalcites, in order to study the acetylation step in the pheromone biosynthesis of this moth. Each application contained one of the alcohols and (Z)-11-tetradecenol, in equi...
Article
The presence of a pheromone biosynthesis activating neurohormone in the head gandlia, and its effect on the sex phermone biosynthetic pathway, were investigated in the tomato looper, Chrysodeixis chalcites (Esper). Comparison of pheromone components and precursor levels in the presence and absence of the factor was performed using untreated, ligate...
Article
The analyses of virgin female sex pheromone gland extracts by gas chromatography (GC), GC-electroantennographic detection (GC-EAD) and GC-mass spectrometry (GC-MS) followed by field-trapping experiments, have identified (E)-9-tetradecenyl acetate (E9–14:Ac) as the primary sex pheromone component of the spruce budmoth,Zeiraphera canadensis. Dosages...
Article
Ten compounds were found in the sex pheromone glands ofHeliothis peltigera (Schiff) and identified as tetradecenal, (Z)-9-tetradecenal, (Z)-9-tetradecenol, (Z)-9-tetradecenyl acetate, hexadecanal, (Z)-7-hiexadecenal, (Z)-9-hexadecenal, (Z)-11-hexadecenal, (Z)-11-hexadecenol, and (Z)-11-hexadecenyl acetate. Behavioral tests in a wind tunnel and subs...
Article
Female pheromone gland extracts of Spodoptera littoralis were analyzed for pheromone precursors. Large amounts of fatty methyl esters were found and a positive relationship between the methyl esters and the pheromonal components was observed. The esters were identified on the basis of capillary gas chromatography, coupled gas chromatography with ma...
Article
The sex pheromone glands ofPlusia chalcites release, dodecyl acetate, (Z)-7-dodecenyl acetate, (Z)-9-dodecenyl acetate, 11-dodecenyl acetate, (Z)-8-tridecenyl acetate, and (Z)-9-tetradecenyl acetate. A combination of capillary GC, GC-MS, and dimethyl disulfide derivatization enabled a rigorous identification of all these compounds, some of which we...
Article
Full-text available
A series of structural analogs of (s+)-cis-(1R)-3-isopropenyl-2,2-dimethylcyclobutanemethanol acetate, sex pheromone of the citrus mealybug,Planococcus citri (Risso), was synthesized. The analogs were tested in a field bioassay in order to determine the structure-activity relationships of the pheromone. All changes in structure reduced the activity...
Article
The sexual behaviour of females of the Egyptian cotton leafworm, Spodoptera littoralis (Boisduval), was studied in the laboratory. Calling of females was maximal on the 2–3rd night between 3 and 9 h into scotophase. Largest amounts of pheromone were found in the glands of 1–3 day-old ♀ ♀ 2–3 h into scotophase: a maximum of 6–8 ng of (Z,E)-9,11-tetr...
Article
The sexual behaviour of Plusia chalcites (Esp.) was recorded in the laboratory and field. Females reached peak activity on the 4th night between 0.5–2 h into the scotophase. Maximal amounts of pheromone were found in the pheromone glands of 4–5-day old females. Male activity was monitored in a wind tunnel and peak activity was observed with 5–8-day...
Article
Male and female Egyptian cotton leafworm, Spodoptera littoralis (Boisduval), mating pairs on plants, and males caught in traps were collected at night in pheromonetreated and untreated plots. A polymeric aerosol formulation containing (Z,E)-9,1l-tetradecadienyl acetate (5,000 release points per ha; total of 75 g [AI]/ha; release rate of ca. 3 g/ha...
Article
The sex pheromone of the citrus mealybug Planococcus citri (Risso), (+)-(1R)-cis-2,2-dimethyl-3-isopropenylcyclobutanemethanol acetate [( + )-cis-planococcyl acetate], is synthesized in four steps from (+ )-α-pinene.
Article
Night observations on the cotton leafworm,Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae), were conducted in pheromone-treated and untreated plots in which males, females, mating pairs on plants, and males caught in traps were collected. Results indicated that emergence of a new population was rapid (8-9 days) and that the number of virgin...
Article
Full-text available
Lures for a monitoring system based on sex attractant trapping of A grotis segetum males were elaborated for Israel and Germany. Various mixtures of (Z)-5-decenyl acetate, (Z)-7-dodecenyl acetate, (Z)-9-dodecenyl acetate, (Z)-9-tetradecenyl acetate, decyl acetate and dodecyl acetate were tested in 20 different blends. From comparison of all the tra...
Article
A rapid analytical procedure for the determination of the position of double bonds in mixtures of monounsaturated fatty acid methyl esters has been developed. The method is based on direct capillary GC-MS-EI analysis of dimethyl disulfide adducts. The procedure was applied to mixtures of monounsaturated fatty esters from pheromone gland extracts of...
Article
The sex pheromone ofEarias insulana, (E,E)-10,12-hexadecadienal, may trimerize extensively to form a crystalline trioxane derivative. The structure of the trimer was deduced from its CI-MS and NMR spectra. Capillary GC analysis resulted in the thermal decomposition of the trimer to the monomer. This process could be studied on a 2-m packed column u...
Article
Full-text available
Z-7-Dodecenyl acetate and Z-7-dodecenyl alcohol have been identified as sex pheromone components of female Autographa gamma.This is the first time that Z-7-dodecenyl alcohol has been found in the natural pheromone of Plusiinae.When incorporated in pherom one traps of some Plusiinae species the alcohol is both synergist and inhibitor, thus being an...
Article
Hercon dispensers, adsorbed with (Z,E)-9,11-tetradecadienyl acetate (1.5 g/ha) and located 65 m apart (one dispenser per 0.4 ha), effectively disrupted communication in Spodoptera littoralis for about 4 weeks. This was inferred from the reduction in trap captures and in number of virgin female traps that captured at least one male in the pheromone-...
Article
Pheromone traps were reliable for detection and estimation of Heliothis armigera adult populations in cotton fields. An increase in male catches in traps was usually followed by an increase in larval density, but no correlation was found between the two. Pheromone traps may therefore serve as a warning device indicating potential attack, but larval...