bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sex pheromones: Achievements in monitoring and mating disruption of cotton pests in Israel
Authors: Kehat Moshe , Dunkelblum Ezra 
Published: February 2005

AbstractIsraeli 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 littoralis, the minor component, Z9,E12–14:Ac, in addition to the major component, Z9,E11–14:Ac, was found to be essential for attracting males. The pheromonal components of Helicoverpa armigera were identified and only two, Z11–16:Ald and Z9–16:Ald, were found to be of importance for attracting males. In Heliothis peltigera two major pheromonal components, Z11–16:Ald and Z9–14:Ald, were identified and a species‐specific lure was developed. Two essential components, E10,E12–16:Ald and Z11–16:Ald, were detected in Earias insulana and proved to be effective in the field. The importance of the dispenser for attracting males was investigated. The efficiency of an Israeli septa was greater than that of other septa presently in use in the U.S.A for attracting H. zea or H. virescens. It was also shown that a more suitable dispenser enables the use of a smaller and easier to handle trap. Different types of traps used in Israel over the years are described. The modern funnel traps that are in wide use today throughout the world have almost the same design as the funnel traps developed in Israel long ago. Generally, there is a positive relation between captures of males in traps and the actual population in the field. However, peak capture of males in traps is somewhat delayed as compared with the peak of females in the field, and corresponds more to the egg peak. Trials carried out in Israel to test a hand‐applied polymeric aerosol formulation containing the major sex pheromone component of S. littoralis gave very promising results. Satisfactory mating disruption by hand application of ShinEtsu ropes was obtained for Pectinophora gossypiella and H. armigera. The pink bollworm P. gossypiella is commercially controlled today in Israel by NoMate or ShinEtsu ropes. Twist‐tie formulations for combined mating disruption of both pink bollworm and E. insulana are also being tested. © 1993 Wiley‐Liss, Inc.
Photostabilization of pesticides by clays and chromophores
Authors: Margulies Leon , Rozen Harel , Stern Theodor , Rytwo Giora , Rubin Baruch , Ruzo Luis O. , Nir Shlomo , Cohen Ephraim 
Published: February 2005

AbstractMechanisms for the photostabilization of pesticides by the use of clays and chromophores are described. The main mechanisms include energy transfer and steric hindrance, whereas the importance of mechanisms such as light scattering and hypsochromic shift is marginal. As an example for energy transfer we describe a procedure where the potent and safe but photolabile insecticide bioresmethrin (BR) is coadsorbed on montmorillonite together with the organic cation methyl green (MG). It is shown that the effective photostabilization of BR occurs by the process of energy transfer, which depends on the matching of energy levels of donor (BR) and acceptor (MG) chromophores, on the distance between them and on their relative orientations. The methods for studying the intermolecular interaction between two coadsorbed organic molecules include Fourier‐transform infrared (FTIR) and 13C solid state magic angle spinning nuclear magnetic resonance (MAS‐NMR) spectroscopies. Energy transfer processes can also occur from the pesticide to the clay. The presence of transition metal ions in the clay can make it an efficient energy or charge acceptor. Such a mechanism was utilized in the photostabilization of the insecticide tetrahydro‐2‐(nitromethylene)‐2H‐1, 3‐thiazine (NMH). In the latter case, improved photostabilization was achieved by an addition of the cationic dye acriflavine (AF). Steric hindrance: here the clay introduces a stereochemical factor in preventing or slowing down certain photochemical reactions. An example is the photostabilization of the dinitroaniline herbicide trifluralin (TF). The energy transfer approach was also shown to be effective in the photostabilization of microbial insecticides, such as the Bacillus thuringiensis (B.t.) toxin. Photoprotection was achieved by adsorption of cationic chromophores such as AF, MG and rhodamin B to B.t. © 1993 Wiley‐Liss, Inc.
Penetration of pesticides and industrial organics deep into soil and into groundwater
Authors: Muszkat Lea , Lahav Doron , Ronen Daniel , Magaritz Mordeckai 
Published: February 2005

AbstractWe report on two different cases of penetration of organic pollutants deep into the soil and into groundwater. In one event a point source of pollution from a pesticides plant has been studied by a long‐term follow‐up of a polluted well close to the plant. A typical pattern of pollution has been observed in this well, which was studied for four years. There was a similar organic pollution pattern in soil samples close to the plant. The second case involved an agricultural area long irrigated with effluents. In this area there was an accumulation of organic pollutants deep in the soil (5–20 m depth) and in the groundwater. The mobilizing effect of effluents in promoting the penetration of micropollutants into the depth of soil has been shown. This effect presumably is due to the presence of surface active components. The reported results demonstrate the facile transport of a wide range of xenobiotic organics deep into the soil and into deep groundwater, and advises caution in the use of reclaimed wastewaters for irrigation. © 1993 Wiley‐Liss, Inc.
Second messengers mediating the effects of testis ecdysiotropin in testes of the gypsy moth, Lymantria dispar
Authors: Loeb Marcia J. , Gelman Dale B. , Bell Robert A. 
Published: February 2005

AbstractExposure of larval and pupal testes of Lymantria dispar to diacyl glycerol mimics, phorbol, 12‐myristate, 13‐acetate, and 11, 12 dibutyryl phorbol ester, induced or augmented synthesis of immunodetectable ecdysteroids. The non‐esterified analog, 4α‐phorbol, had little effect. H‐7, a protein kinase C inhibitor, inhibited ecdysteroid synthesis. When testis ecdysiotropin and phorbol esters were administered together at the maximum effective dose of each, steroidogenesis was further enhanced. Therefore, diacyl glycerol may be a second messenger for testis ecdysiotropin in testes. In addition, testis ecdysiotropin induced a rapid rise and fall in cAMP titers in both larval and pupal testes. The cyclic AMP analog, dibutyryl cyclic AMP, induced ecdysteroid synthesis in larval testes, but had little steroidogenic effect in pupal testis sheaths. However, dibutyryl cyclic AMP inhibited the steroidogenic effect of testis ecdysiotropin in larval as well as pupal testes. Cyclic AMP may act to modulate the effects of testis ecdysiotropin in inducing ecdysteroid synthesis by testes of L. dispar. © 1993 Wiley‐Liss, Inc.
Analysis of lipids in the salivary glands of Amblyomma americanum (L.): Detection of a high level of arachidonic acid
Authors: Shipley Michael M. , Dillwith Jack W. , Sauer John R. , Essenberg Richard C. , Howard Ralph W. 
Published: February 2005

AbstractAnalysis of lipids in salivary glands of the lone star tick, Amblyomma americanum, demonstrated that arachidonic acid (20:4, n‐6) comprises 8% of all fatty acids identified by gas chromatography. The occurrence of arachidonic acid and other C20 polyunsaturated fatty acids in tick salivary glands was confirmed by gas chromatography‐mass spectrometry. Arachidonate is located entirely in the phospholipid fraction and is associated exclusively with phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Salivary glands stored and frozen for several months had a similar lipid composition as freshly dissected salivary glands, with the exception of a small amount of free arachidonic acid and an increase in lysophosphatidylcholine. Incubation of salivary gland homogenates with snake venom phospholipase A2 showed that most saturated fatty acids are esterified in the sn‐1 position of PC and PE, with the unsaturated fatty acids in the sn‐2 position. Approximately 75% of arachidonic acid is in the sn‐2 position of PC and PE, adding support to the hypothesis that arachidonic acid is released into the cytoplasm after activation of a phospholipase A2 for subsequent metabolism to prostaglandins and/or other eicosanoids. © 1993 Wiley‐Liss, Inc.
Metabolism of [3H]‐ecdysone in embryos and larvae of the tick Ornithodoros moubata
Authors: Dotson Ellen M. , Connat Jean‐Louis , Diehl Peter A. 
Published: February 2005

AbstractThe fate of [3H]‐ecdysone ([3H]‐E) was investigated in hanging drop cultures of embryos and larvae of the tick Ornithodoros moubata using HPLC. The hormone was metabolized more slowly during described periods of increasing endogenous ecdysteroid (ES) titers than during periods of low titers except for young embryos. Three different classes of metabolites were produced: (1) apolar products (AP) corresponding to C‐22 fatty acid ester conjugates of E and, in some cases, of 20‐hydroxyecdysone (20E), (2) unidentified polar products (PP) more polar than E, one peak of which had the same retention times as 20,26‐dihydroxyecdysone, and finally, (3) 20E verified by comigration of cold standards on RP‐18 and silica columns. Hydroxylation of E to 20E first became evident in cultures of 2 day old embryos and was present in all cultures of older animals. Highest production of free 20E occurred during increasing endogenous ES titers in embryos and during the ES peak in larvae. Conjugation of E to AP occurred in all stages investigated, but was more pronounced during periods of low endogenous ES titers, and may correspond to a detoxification mechanism. In contrast, PP were produced during high 20E production in embryos and during periods of high and decreasing endogenous titers in larvae. © 1993 Wiley‐Liss, Inc.
Neosurugatoxin blocks an α‐bungarotoxin‐sensitive neuronal nicotinic acetylcholine receptor
Authors: Bai Donglin , Sattelle David B. 
Published: February 2005

AbstractNeosurugatoxin (NSTX), a neurotoxin isolated from the Japanese ivory mollusc Babylonia japonica, is a potent neuronal nicotinic acetylcholine receptor (nAChR) antagonist. Hitherto, NSTX has been found to block only neuronal nAChRs that are insensitive to α‐Bgt. Here, we report for the first time that NSTX blocks an α‐Bgt‐sensitive nAChR on an identified insect motor neurone. Bath‐applied NSTX at a concentration of 10 nM and above reversibly blocks the nicotine‐induced depolarizations recorded from the cockroach (Periplaneta americana) fast coxal depressor motor neurone (Df) and is without effect on GABA‐induced responses detected on the same cell. NSTX is among the most potent blockers tested to date on nAChRs of motor neurone Df. © 1993 Wiley‐Liss, Inc.
On the control of ecdysone biosynthesis by the central nervous system of blowfly larvae
Authors: Budd Evelyn , Käuser Gerd , Koolman Jan 
Published: February 2005

AbstractEcdysone was found to be the major secreted steroid of ring glands dissected from blowfly larvae and incubated in vitro. Other secretory products such as 3‐dehydroecdysone and 20‐deoxy‐makisterone A could not be detected when the glands were labelled with tritiated cholesterol. Ecdysone synthesis and secretion were found to be tightly coupled. The highest rate of secretion was observed a few hours before pupariation. In vitro, the rate of ecdysone secretion by ring glands was affected significantly by coincubation with the central nervous system (CNS). Modulating effects from the CNS to the gland were mediated both by culture medium and by nerve connections. Distinct parts of the CNS revealed multiple and partially opposite effects on ecdysone secretion, suggesting a more complex control than had been anticipated. Multiple neural control systems appear to be involved. Moreover, the observed effects changed with development during the second half of the third instar, reflecting a significant plasticity of neural control. © 1993 Wiley‐Liss, Inc.
Ecdysone oxidase and 3‐oxoecdysteroid reductases in Manduca sexta: Developmental changes and tissue distribution
Authors: Weirich Gunter F. , Feldlaufer Mark F. , Svoboda James A. 
Published: February 2005

AbstractThe activities of ecdysone oxidase (EO), 3‐oxoecdysteroid 3α‐reductase (3α‐R), and 3‐oxoecdysteroid 3β‐reductase (3β‐R) were determined for epidermis, hemolymph, and fat body of wandering fifth instar Manduca sexta larvae and for midguts of various developmental stages between 3 days after the last larval and 14 days after the pupal ecdysis. The larval midgut was the only organ showing substantial specific activities of EO and 3α‐R, and both increased up to the seventh day after ecdysis. Hemolymph and fat body had only moderate to high 3β‐R and low EO activites, and the epidermis did not contain significant activity of any of the enzymes. On the ninth day after the last larval ecdysis the larval midgut epithelium was replaced by a new pupal midgut epithelium. After this event only 3β‐R was restored to high activities, whereas EO and 3α‐R showed only low to marginal activities. It is concluded that only the larval midgut has a role in the inactivation of ecdysteroids by 3‐epimerization. © 1993 Wiley‐Liss, Inc. This article is a US Government work and, as such, is in the public domain in the United States of America.
Changes in the size of corpora allata, in the juvenile hormone III titer in the hemolymph, and in the protein content of terminal oocytes throughout the first gonadotropic cycle in Aiolopus thalassinus (Insecta: Orthoptera: Acrididae)
Authors: Schmidt Gerhard H. , Othman Kamal S. A. 
Published: February 2005

AbstractIn Aiolopus thalassinus (Fabr.), the changes in the volume of the corpora allata (CA), in the concentration of juvenile hormone III (JH III) in the hemolymph, and in protein content in the terminal (t) oocytes were studied during the first gonadotropic cycle. These parameters could be better related to the volume of t‐oocytes than to age after emergence. The JH III titer curve was maximum (2.9 pmol/10 μl) at an oocyte volume of 1.2 mm3. Before oviposition (days 10–16) the JH III titer decreased to 0.65 pmol/10 μl hemolyph. The increase in JH III titer reflected a period of high protein storage in the t‐oocytes. The largest volume of the CA was reached at the beginning of yolk storage in the t‐oocytes. The highest JH III titer did not correspond with the largest volume of CA, which occurred much earlier. © 1993 Wiley‐Liss, Inc.
Growth and development of Cardiochiles nigriceps viereck (hymenoptera, braconidae) larvae and their synchronization with some changes of the hemolymph composition of their host, Heliothis virescens (F.) (Lepidoptera, Noctuidae)
Authors: Pennacchio Francesco , Vinson S. Bradleigh , Tremblay Ermenegildo 
Published: February 2005

AbstractLarval development of the parasitoid Cardiochiles nigriceps Viereck occurs in the last instar larva of its host, Heliothis virescens (F.). This allows the parasitoid to exploit the nutritional increase in the biosynthetic activity occurring in the host in preparation for metamorphosis. To understand the biochemical basis of this host parasitoid developmental synchrony, we undertook host ligation studies and analyzed host hemolymph for proteins and glycerol esters. Parasitization affected the biochemical profile of the host. The hemolymph protein concentration of parasitized last instar H. virescens larvae increased through time, whereas unparasitized (control) larvae were characterized by a decrease in the protein titer when they reached the prepupal stage. The effect of parasitism on glyceride titers of host hemolymph was not as pronounced as the effect on proteins. Ligation conducted on 5th instar hosts, which were parasitized as 4th instars, affected parasitoid development in a time‐dependent way. The percentage of successfully developing C. nigriceps larvae increased with the increase of the time interval between parasitization and ligation. Ligation performed before day 2 of the 5th larval instar of H. virescens completely inhibited parasitoid development. Ligations that disrupted parasitoid developmentwere associated with a low host hernolymph protein concentration. Parasitoid development was successful when hernolymph protein titer was high, as occurred when ligations were performed after day 3 of the 5th host instar in both control and parasitized larvae. Ligations in both situations resulted in a slight increase in glyceride titers. The results suggest that host proteins and/or some factor(s) associated with them may play a role in parasitoid growth and development. © 1993 Wiley‐Liss, Inc.
Control of pheromone biosynthesis in mated redbanded leafroller moths
Authors: Jurenka Russell A. , Fabriás Gemma , Ramaswamy Sonny , Roelofs Wendell L. 
Published: February 2005

AbstractMating in the redbanded leafroller moth, Argyrotaenia velutinana, causes a permanent decline in pheromone titers. Three hours following the termination of mating, phermone titers were significantly decreased from premating levels, and titers remained low for at least four days after mating. Pheromone titers were similar in females that had been decapitated or mated for twenty‐four hours. In the redbanded leafroller moth, two peptides control pheromone production. The pheromone biosynthesis activating neuropeptide is produced in the brain and the pheromonotropic bursa peptide is produced in the corpus bursae. Both peptides stimulated pheromone biosynthesis in mated females and extracts prepared from brains and bursae of mated females contained pheromonotropic activity. However, severing the ventral nerve cord before mating prevented the decline in pheromone titer that occurred in mated females. Hemolymph collected during scotophase from mated females did not have pheromonotropic activity, whereas hemolymph collected during scotophase from virgin females contained activity. These results indicate that mating produces a signal sent by the ventral nerve cord to the brain to stop the release of pheromone biosynthesis activating neuropeptide. © 1993 Wiley‐Liss, Inc.
Expression of a parasitism‐specific protein in lepidopteran hosts of Chelonus sp.
Authors: Soldevila Ana I. , Jones Davy 
Published: February 2005

AbstractThe hemolymph of each noctuid species successfully parasitized by Chelonus near curvimaculatus possessed a parasitism‐specific protein (PSP) previously identified in host T. ni (Insect Biochem. 19:445; 21:845). Expression of PSP occurred in a stage‐specific manner in the stadium during which the host undergoes precocious metamorphosis. The appearance of the protein was not due to nutritional stress associated with parasitism of hosts, since starved nonparasitized larvae did not produce the protein, or to low juvenile hormone titers occurring in precociously metamorphosing hosts, but rather was dependent on the presence of the endoparasite larva. Results of in vivo incorporation experiments with [35S]‐methionine showed that synthesis and subsequent appearance of the protein in the hemolymph of parasitized hosts was abrogated by prior surgical removal of endoparasite. Immunoprecipitation analysis of proteins from C. near curvimaculatus larvae cultured in vitro using antibodies specific to PSP indicated that the source of the protein was the endoparasite. Synthesis of PSP by the endoparasitic larvae with its subsequent secretion into the hemocoel of hosts was specific to the advanced stages of parasite development prior to its egression from the host. © 1993 Wiley‐Liss, Inc.
Phospholipase A2 activity in the fat body of the tobacco hornworm Manduca sexta
Authors: Uscian John M. , Stanley‐Samuelson David W. 
Published: February 2005

AbstractWe report on phospholipase A2 (PLA2) activity in homogenates prepared from fat bodies of the tobacco hornworm Manduca sexta. PLA2 activity is responsible for hydrolyzing fatty acids from the sn‐2 position of phospholipids. The rate of hydrolysis increased with increasing homogenate protein concentration up to ∼︁ 320 μg protein/ml reaction volume. Higher protein concentrations did not appreciably increase the rate of PLA2 activity. As seen in some, but not all PLA2s from mammalian sources, hydrolyzing activity increased linearly with time. The fat body activity was sensitive to pH (optimal activity at pH 8–9) and temperature (optimal activity at ∼︁40°C). The activity was associated with fat body rather than hemolymph, because no activity was detected in cell‐free serum. The fat body PLA2 activity differs from the majority of PLA2s with respect to calcium requirements. Whereas most PLA2s are calcium‐independent. A few others are known to require submicromolar calcium concentrations. The fat body activity appears to be calcium independent. These data show that a PLA2 activity that can hydrolyze arachidonic acid from the sn‐2 position of phospholipids is associated with the tobacco hornworm fat body. The biological significance of this activity relates to biosynthesis of eicosanoids. Pharmacological inhibition of PLA2 impairs the ability of this insect to respond to bacterial infections. Since the impairment can be reversed by treatment with exogenous arachidonic acid, the PLA2 activity may be an important step in eicosanoid biosynthesis. © 1993 Wiley‐Liss, Inc.
Tissue‐specific changes in polyamine levels of neural tissue and fat body in adult crickets
Authors: Strambi Colette , Faure Philippe , Renucci Marielle , Charpin Pierre , Augier Roger , Tirard Alain , Strambi Alain 
Published: February 2005

AbstractThe three major polyamines—putrescine, spermidine, and spermine—were studied and changes of their levels were examined in extracts of cerebral ganglia and fat body from adult Acheta domesticus. In nervous tissue, only spermidine and spermine were present and spermine was two‐ to three‐fold more abundant than spermidine. The polyamine levels were high up to day 3, decreased on day 4, and then remained relatively unchanged up to day 10. The spermidine/spermine ratios decreased during the imaginal life. Higher spermidine titres were observed in the neural tissue of egg‐laying females compared to virgin females. In the fat body, putrescine was detected together with spermidine and spermine. Spermidine and spermine levels were two‐fold higher than putrescine. Fat body of virgin females contained two times more polyamines than male fat body. Low at emergence, spermidine and spermine concentrations peaked on days 2–3 only in females, and egg‐laying was characterized by an increase of putrescine and spermidine titres. Starvation did not change polyamine contents, implying homeostatic regulation of the intracellular polyamine metabolism. These data showing tissue specific changes in polyamine levels during the imaginal life of Acheta domesticus point to the physiological importance of polyamines as possible intracellular regulators during adult insect development. © 1993 Wiley‐Liss, Inc.