bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insect neuropeptides: Discovery and application in insect management
Authors: Masler Edward P. , Kelly Thomas J. , Menn Julius J. 
Published: February 2005

AbstractNew approaches to the development of insect control agents have been revealed through the molecular description of neuropeptides, their biogenesis, action, and degradation. Prerequisite to the exploitation of a neuropeptide as a lead to control agent development is a thorough understanding of the biochemistry of the neuropeptide and appreciation of its physiological impact. Reliable bioassays must be coupled with advanced biochemical and molecular genetic technologies to overcome limitations imposed by the typically low endogenous levels of individual neuropeptides. Purification, amino acid sequencing, and gene cloning provide the molecular tools necessary for studies on neuropeptide synthesis, processing, secretion, receptor binding, and inactivation. Each of these areas consists of a number of amino acid sequence‐, and enzyme‐dependent steps which may be considered as targets for the development of highly specific control agents. These agents will include antagonists and superagonists, peptidomimetics, recombinant peptides delivered through the baculovirus technology, receptor blockers, and enzyme inhibitors. © 1993 Wiley‐Liss, Inc.
Pheromone biosynthesis activating neuropeptide: From discovery to current status
Authors: Raina Ashok K. , Menn Julius J. 
Published: February 2005

AbstractSex pheromone production in females of many species of moths is controlled by a pheromone biosynthesis activating neuropeptide (PBAN). PBAN from Helicoverpa zea (Hez‐PBAN) is a 33 amino acid peptide produced in the suboesophageal ganglion of both female and male moths. PBAN‐like activity is widespread among Lepidoptera and is also reported from a cockroach and a grasshopper. The C‐terminal pentapeptide of Hez‐PBAN represents the minimum sequence with pheromonotropic activity. Another pentapeptide fragment of the molecule also has high pheromonotropic activity. Presence of PBAN‐like immunoreactivity and biological activity in the corpora cardiaca suggests that it is the possible site of PBAN release. There is evidence that PBAN action on pheromone gland is mediated by a second messenger. Several possible sites of action of PBAN have been suggested in the biosynthetic pathway of pheromones. The gene for Hez‐PBAN has been cloned and sequenced. Cloning of a synthetic PBAN gene into a baculovirus has been attempted. Studies to isolate and identify the receptors for PBAN as well as the metabolic fate of PBAN have been initiated. © 1993 Wiley‐Liss, Inc.
Neuroendocrine control of sex pheromone biosynthesis in Heliothis peltigera
Authors: Alstein Miriam , Gazit Yoav , Dunkelblum Ezra 
Published: February 2005

AbstractSex 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 the studies are controversial, mainly those related to: (1) the route of transport of PBAN to its target organ, (2) the nature of the target organ of PBAN, (3) the possible involvement of other stimulatory and inhibitory neural and nonneural factors in the regulation of sex pheromone biosynthesis, (4) the structure‐function relationship of the neuropeptide, and (5) the effect of PBAN on the enzymatic steps involved in pheromone biosynthesis in the gland. In this work, we summarize the results obtained in our laboratory on the regulation of sex pheromone biosynthesis by PBAN in Heliothis peltigera and shed light on some of these controversial issues. © 1993 Wiley‐Liss, Inc.
Influence of photoperiod and age on the competence of pheromone glands and on the distribution of immunoreactive PBAN in Helicoverpa spp.
Authors: Rafaeli Ada , Soroker Victoria , Hirsch Jaquelyn , Kamensky Batya , Raina Ashok K. 
Published: February 2005

AbstractPheromone glands (eighth and ninth abdominal segments) of Helicoverpa spp. can be stimulated in vitro by brain‐suboesophageal ganglion (Br‐SOG) extracts and Helicoverpa zea pheromone biosynthesis activating neuropeptide (Hez‐PBAN) to produce the sex pheromone. The main pheromone component, (Z)‐11‐hexadecenal, was quantified by both TLC and gas chromatographic analyses. This stimulation was shown to be a specific response attributed to pheromone glands alone. The glands were found to be competent to Br‐SOG extracts/Hez‐PBAN stimulation from the first day after emergence during both the photophase and scotophase. Using a sensitive and specific RIA the distribution of PBAN along the central nervous system was studied and PBAN‐immunoreactivity in Br‐SOG complexes was found throughout the photoperiod and in all ages (from the first day of emergence until the fourth night after emergence). From the distribution of PBAN immunoreactivity it appears that PBAN release is affected by the photoperiod. This integrative study on the competence of the target tissue and the distribution of PBAN activity revealed evidence that the neuroendocrine control of pheromone production operates at the level of neuropeptide production and/release and not at the level of the target tissue itself. © 1993 Wiley‐Liss, Inc.
Negatively correlated cross resistance: Combinations of N‐methylcarbamate with N‐propylcarbamate or oxadiazolone for green rice leafhopper
Authors: Yamamoto Izuru , Kyomura Nobuo , Takahashi Yoji 
Published: February 2005

AbstractThe use of insecticide mixtures is generally considered to result in the simultaneous development of resistance to the components. However, experiences with leaf and planthoppers do not necessarily support this opinion and indicate that the N‐methylcarbamate/N‐propylcarbamate combination can overcome the resistance of the green rice leafhopper (GRLH) by synergism between the two components. It was found that the N‐methylcarbamate/oxadiazolone combination gave a similar but more remarkable synergism than the former combination. The mechanism of synergism was studied by the analysis of acetylcholinesterase (AChE) inhibition using the log v‐t plot. AChE from the resistant population is provided with two active sites, one being sensitive to N‐methylcarbamate and oxadiazolone compounds and the other being insensitive to N‐methylcarbamates but highly sensitive to oxadiazolones. The overall results indicate that the biochemical mechanism of action of the N‐methylcarbamat/oxadiazolone combination is essentially the same as that of the N‐methylcarbamate/N‐propylcarbamate combination. Selection of susceptible GRLH by a N‐methylcarbamate developed the cross‐resistance to the whole N‐methylcarbamate group; but the population became more susceptible to N‐propylcarbamates. When further selected by the N‐methylcarbamate/N‐propylcarbamate combination, no further resistance developed to the combination or its components. Thus, certain combinations of insecticides may be useful in resistance management. © 1993 Wiley‐Liss, Inc.
Development of recombinant viral insecticides by expression of an insect‐specific toxin and insect‐specific enzyme in nuclear polyhedrosis viruses
Authors: Hammock Bruce D. , McCutchen Billy F. , Beetham Jeffrey , Choudary Prabhakara V. , Fowler Elizabeth , Ichinose Reiji , Ward Vernon K. , Vickers Joanna M. , Bonning Bryony C. , Harshman Lawrence G. , Grant David , Uematsu Tamon , Maeda Susumu 
Published: February 2005

AbstractAs supplements to classical chemical insecticides, two approaches to develop recombinant baculovirus insecticides are described. In one approach an insect‐specific toxin is expressed leading to a dramatic reduction in time to death. In the second approach an insect juvenile hormone esterase is expressed which leads to a reduction in feeding. Modifications of the wildtype esterase led to viruses which reduced the time to death as efffectively as did the toxin‐expressing virus. In both cases existing recombinant viruses are viewed as leads, and approaches to further improvement in the engineered viruses are suggested. Many of these approaches are based on analogy with the development of classical synthetic insecticides. Using these viruses as examples, the potential utility and limitations of recombinant viruses and other biological insecticides are discussed. © 1993 Wiley‐Liss, Inc.
Insecticidal potential of the insect parvovirus GmDNV
Authors: Tal Jacov , Attathom Tipvadee 
Published: February 2005

AbstractThe insecticidal potential of Galleria mellonella densovirus (GmDNV) in third, fourth, and fifth instar larvae of the host, the greater wax moth, as a step toward the construction of a molecular vector for the introduction and expression of foreign genes in the larvae of these insects was studied. Third instar larvae are most susceptible to GmDNV. Viral RNA synthesis is more rapid in this stage and slowest in the fifth instar. Infection of prepupae by intradermic injection or by horzontal spread inhibited pupation. GmDNV DNA is also infectious when introduced as a calcium phosphate precipitate. The two putative viral promoters were shown to be capable of driving the expression of the reporter gene chloramphenicol acetyltransferase (CAT) in DNA‐injected larvae. © 1993 Wiley‐Liss, Inc.
Chemical characterization and species specificity of sex pheromones of plusiinae moths in Israel
Authors: Dunkelblum Ezra , Mazor Michal 
Published: February 2005

AbstractThe 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 by analysis of pheromone gland extracts, and in addition entrained volatiles released from virgin female C. chalcites and T. ni were also analyzed. The pheromones of these latter two species were found to contain several components, among which Z7‐12:Ac was the main one. The pheromone glands of A. gamma and C. circumflexa were found to contain relatively small amounts of material and only Z7–12:Ac and Z7–12:OH could be positively identified. These two pheromone components were present in the two species in roughly inverse rations. Whereas A. gamma utilizes Z7–12:Ac as the main or sole pheromone component, C. circumflexa requires both Z7–12:OH and Z7–12:Ac, with the alcohol being predominant. This is the first reported Plusiinae species using Z7–12:OH as the main pheromone component. Behavioral studies in the wind tunnel and field tests indicate that females of each of the four Plusiinae species utilizes a species‐specific blend of chemicals, consisting of attractive and antagonistic components, to attract conspecific males. Such a complementary strategy provides improved behavioral reproductive isolation among the sympatric species. For example, Z5–12:Ac, which is a specific component of the T. ni sex pheromone, may be redundant as regards the attraction of T. ni males. However, addition of small amounts of this compound to pheromone blends of A. gamma and C. chalcites resulted in complete inhibition of the males' flight behavior and trap catch; thus contributing significantly to the specificity of the T. ni sex pheromone. The relatively high proportion of Z7–12:OH in the sex pheromone of C. circumflexa, essential to the latter, is highly inhinitory to the three other Plusiinae species. The only case of cross‐attraction occurred when T. ni males were attracted to a certain extent to A. gamma lures and females. © 1993 Wiley‐Liss, Inc.
Nonconventional insecticidal effects of pesticides available from the Neem tree, Azadirachta indica
Authors: Ascher K. R. Simon 
Published: February 2005

AbstractNonconventional insecticidal effects are exerted by preparations from the Neem tree, also called Indian lilac or Margosa tree (Azadirachta indica A. Juss, syn. Melia azadirachta L. or Antelaea azadirachta L.) (Meliaceae). A closely related species, the chinaberry tree or Persian lilac (Melia azedarch L.), is a source of substances with similar strctures and insecticidal activity. However, the seed kernels, whole fruits or leaves of many M. azedarch chemotypes contain tetranortriterpenoids and other principles highly toxic to mammals (meliatoxins). The most prominent insecticidal constituent of Neem seed kernels is the tetranortriterpenoid azadirachtin and related structures. Lesser concentrations of these active materials are found in the leaves and other parts of the tree. Third World farmers use crude Neem preparations, mainly seed kernel extracts or powders, as insecticides. An industrial Neem product, called Margosan‐O, is in commercial use in the USA. The nonconventional effects of preparations or compounds isolated from Neem may be classified as follows: (i) partial reduction or complete inhibition of fecundity and/or sometimes egg hatchability; (ii) reduction of the life span of adults; (iii) oviposition repellence against females; (iv) direct ovicidal effects; (v) antifeedant effects against larvae (and nymphs) and adults; (vi) formation of permanent larvae; (vii) insect growth regulator effects at molting between larval (or nymphal) instars and especially in the prepupal stage; and (viii) analogous lesions during the emergence of adults. Phenomena (vii) and (viii) give rise to characteristic larval‐pupal, nymphal‐pupal, nymphal‐adult and pupal‐adult intermediates, and to crippled adults. © 1993 Wiley‐Liss, Inc.
Delayed and enhanced biodegradation of soil‐applied diphenamid, carbendazim, and aldicarb
Authors: Aharonson Nadav , Katan Jaacov 
Published: February 2005

AbstractRecent studies have demonstrated that interaction between various agrochemicals and soil microorganisms may either slow down or enhance processes of degradation. Soil disinfestation is employed for the control of soil‐borne pathogens and weeds. Soil application of such broad‐spectrum biocides, as well as some more selective chemicals, has a strong effect on microbial activity, which may result in drastic reduction in the rate of degradation of pesticides applied to such treated soils. Application of pesticides to previously disinfested soils may extend their biological activity, which in the case of herbicides could cause phytotoxic damage to the next crop. In contrast, repeated application of the same or structurally related pesticides may result in a selective buildup of microbial populations capable of degrading the pesticide at much faster rates. Cases of accelerated degradation were reported for pesticides belonging to various chemical groups. Studies were conducted to evaluate the mechanisms of accelerated degradation. For several pesticides it has been shown that soil fungi are involved in their normal degradation, but not in their accelerated degradation. The shift in the rate of degradation of pesticides such as diphenamid, benomyl, and S‐ethyl dipropylthiocarbamate, in soils that have acquired accelerated degradation, seems to be associated with the buildup of populations of bacterial degraders. Moreover, it has been shown that for the herbicide diphenamid, accelerated degradation is apparently linked to the induction of an oxidative demethylation process in soil bacteria, which might be analogous to the development of resistance in pests. Contrary to studies demonstrating accelerated degradation of the systemic insecticide aldicarb and accumulation of aldicarb sulfoxide in non‐history soils, our work has shown that repeated application of this carbamate at several locations in Israel over a 10‐year period did not induce accelerated degradation. It should be pointed out that in the Israeli soils there was only minimal formation of aldicarb sulfoxide. These studies were performed in soils with a pH ranging from 7.8 to 8.3, which is higher than the pH reported for soils where accelerated degradation was detected. © 1993 Wiley‐Liss, Inc.
Cholinesterase profiles in two species of wild birds exposed to insecticide sprays in their natural habitat
Authors: Yawetz Aminadav , Zook‐Rimon Zohar , Dotan Aharon 
Published: February 2005

AbstractDuring summer season, a field survey was conducted to assess the extent of stress to which two species of wild birds might have been subjected, due to their dwelling near cotton fields sprayed with insecticides. One of the bird species, the cattle egret Bubulcus ibis, showed no significant changes either in brain acetylcholinesterase (AChE) or in plasma butyrylcholinesterase (BuChE) activities in samples collected before, during, and after the spraying season. With the spur‐wing plover, Hoplopterus spinosus, there was a significant decrease both in brain AChE and plasma BuChE activities in July and August, the period when insecticide spray was most frequent. In laboratory experiments it was found that this species could survive higher doses of parathion, and specimens surviving the treatment showed higher residual plasma BuChE activity and a faster return of that activity to normal compared to Bubulcus specimens. Brain AChE from the Hoplopterus showed a lower Ki value for inhibition by paraoxon or malaoxon compared to the same values recorded for the Bubulcus, indicating that the enzyme from the Hoplopterus brain is less sensitive to inhibition by paraoxon or malaoxon. The finding that the more resistant Hoplopterus showed a decrease in cholinesterase activity during the cotton spraying season may therefore be due to the territorial habits of this species. © 1993 Wiley‐Liss, Inc.
24‐Epi‐makisterone a (not makisterone A) is the major ecdysteroid in the leaf‐cutting ant Acromyrmex octospinosus (reich) (hymenoptera, formicidae: Attini)
Authors: Maurer Patricia , Girault Jean‐Pierre , Larchevêque Marc , Lafont René 
Published: February 2005

AbstractThe chemical nature of the major ecdysteroid from pupae of the leaf‐cutting ant Acromyrmex octospinosus has been reinvestigated. On the basis of reversed phase high performance liquid chromatography and mass spectrometry, this compound was previously identified as makisterone A [Maurer et al., Arch Insect Biochem Physiol 16, 1 (1991)] but a more careful examination has led to the conclusion that it is in fact 24‐epi‐makisterone A. This finding stresses the limits of criteria used for the identification of ecdysteroids and the possible need for reexamination of makisterone A identification in some other species feeding on a 24β‐methyl sterol source. © 1993 Wiley‐Liss, Inc.
Food utilization and antioxidant enzyme activities of black swallowtail in response to plant phototoxins
Authors: Lee Keywan , Berenbaum May R. 
Published: February 2005

AbstractPhototoxic compounds are widely distributed among plant families; due to their ability to bind covalently to DNA or to react with oxygen and generate toxic oxyradicals, these compounds are toxic to a variety of herbivorous organisms. Black swallowtail (Papilio polyxenes) larvae feed exclusively on phototoxic host plants in the Apiaceae and Rutaceae. In this study, we examined the toxicity of four phototoxins—three furanocoumarins and one β‐carboline alkaloid—to P. polyxenes, as well as the inducibility of antioxidant enzyme defenses in response to these phototoxins. Neither the furanocoumarins nor the β‐carboline alkaloid demonstrated any toxic effect on digestive efficiencies of P. polyxenes in the presence of light; harmine, the alkaloid, did significantly reduce growth and consumption rates. None of the compounds had a significant effect on antioxidant enzyme levels. These findings contrast with those reported in earlier studies for Trichoplusia ni, a generalist noctuid sensitive to both furanocoumarins and β‐carboline alkaloids. Greater detoxicative metabolic capabilities, coupled with substantially higher constitutive levels of antioxidant enzyme activity, likely explain at least in part the absence of induced antioxidant enzyme responses in the specialist feeder on phototoxic plants. © 1993 Wiley‐Liss, Inc.
Characterization of a diuretic hormone receptor from the tobacco hornworm, Manduca sexta
Authors: Regan Jeff D. , Li Jorge P. , Carney Robert L. , Kramer Steven J. 
Published: February 2005

AbstractWe have characterized a diuretic hormone receptor from the tobacco hornworm, Manduca sexta. A single high affinity binding site for the 41 amino acid M. sexta diuretic hormone was found in membranes prepared from Malpighian tubules of fifth stadium larvae. The site has a Kd = 79 pM and Bmax = 3.1 pmol/mg protein. The dissociation rate constant was determined to be 0.11 min−1 with a corresponding half‐life of 6.4 min. Receptor binding of the hormone is inhibited by Ca2+ and Mg2+, while Na+ and K+ inhibit binding to a lesser extent. Truncated diuretic hormone analogs in which up to 20 amino acids were removed from the N‐terminus maintain high affinity for the receptor. A diuretic hormone from Locusta migratoria which has 43% sequence identity with the M. sexta diuretic hormone also possesses a high affinity for the receptor. Conformational analysis of the M. sexta diuretic hormone indicates the core region of the peptide assumes a helical conformation, which may have implications in the binding of the peptide to the receptor. © 1993 Wiley‐Liss. Inc.
Induction of detoxification enzymes in phytophagous insects: Role of insecticide synergists, larval age, and species
Authors: Yu Simon J. , Hsu Err L. 
Published: February 2005

AbstractFive insecticide synergists, all of which were either methylenedioxyphenyl compounds or analogs, were compared as to their effect on cytochrome P450 monooxygenase induction caused by an allelochemical in fall armyworm larvae. Feeding the synergists (piperonyl butoxide, safrole, isosafrole, MGK 264, and myristicin) individually to the larvae caused decreases in the microsomal aldrin epoxidase activities ranging from 38% to 74% when compared with controls. Feeding indole‐3‐carbinol resulted in a 4‐fold increase in the microsomal epoxidase activity. However, cotreatment of any of the synergists and the inducer completely eliminated the induction. Sixth instar larvae were more inducible than second instar larvae with respect to microsomal epoxidase and glutathione transferase in the fall armyworm. Enzyme inducibility varied widely among the seven phytophagous Lepidoptera examined. When indole‐3‐carbinol was used as an inducer of microsomal epoxidase, the extent of inducibility of the enzyme was fall armyworm > velvetbean caterpillar > corn earworm > beet armyworm > tobacco budworm > cabbage looper > diamondback moth. When indole‐3‐acetonitrile was used as an inducer, the inducibility of glutathione transferase was fall armyworm > beet armyworm > corn earworm > cabbage looper > velvetbean caterpillar > tobacco budworm > diamondback moth. Inducibility of five microsomal oxidase systems also varied considerably in the corn earworm, indicating the multiplicity of cytochrome P450 in this species. Microsomal epoxidase and glutathione transferase were induced by cruciferous host plants such as cabbage and their allelochemicals in diamondback moth larve. © 1993 Wiley‐Liss, Inc.
Basic isoforms of hemolymph storage proteins expressed during larval metamorphosis
Authors: Jones Grace , Sarkari Neville 
Published: February 2005

AbstractThe hemolymph of metamorphosing, final instar larvae of Trichoplusia ni was analyzed for the presence of basic forms of normally positively charged storage proteins. Basic forms of arylphorin and a normally acidic juvenile hormone suppressible protein were identified. For each of these two proteins, variation was observed in the immunoreactivity of forms with different basic charges, where the antisera had been generated against acidic forms of each protein. A basic protein of high molecular size (ca. M, 150,000) was identified that cross‐reacted specifically with an antiserum raised against a normally basic, M 74,000 juvenile hormone suppressible protein in the hemocyanin superfamily. © 1993 Wiley‐Liss, Inc.