Publications

action spectra for prevention or termination of diapause in three species of lepidoptera.	action spectra for photoperiodic induction or termination of diapause in three species of lepidoptera were determined by synchronizing the appropriate stage in an ld 16:8 regimen in which a 12-hr day of cw fluorescent light was extended by 6 hr of spectral light. a combination of full- and half- silvered mirrors were used to direct the spectral light, which passed through appropriate combinations of interference filters onto each of the three groups of insects in each test conducted. the action ...	1987	3601961
mode of action of the sesquiterpene lactone, tenulin, from helenium amarum against herbivorous insects.	tenulin [1], a sesquiterpene lactone from helenuim amarum, is a potent antifeedant to the european corn borer ostrinia nubilalis. at 3 mumol/g in artificial diets, 1 reduced growth and delayed larval development of o. nubilalis and the variegated cutworm peridroma saucia larvae. an especially pronouned carry-over effect in o. nubilis was substantial reduction in fecundity of adult moths resulting from treated larvae. the ld50 (lethal dose for 50% mortality) of 1 by injection in the migratory gra ...	1987	3430166
diapause induction and termination: north-south strain differences in ostrinia nubilalis.	diapause induction and termination responses of a northern strain (minnesota [mn]) of ostrinia nubilalis were compared with those of a southern strain (georgia [ga]). a thermoperiod in constant light (12 hr at 25 degrees c alternating with 12 hr at 4 degrees c) failed to induce diapause in ga larvae, but approximately 50% diapause induction was observed in the mn population. moreover, the 50% of mn larvae that continued their development (i.e., underwent pupation and adult development) did so at ...	1987	2979648
insect photoperiodism: diversity of results in night-break experiments, including nonresponsiveness to light.	three night-break experiment protocols were utilized in an attempt to help clarify the role of the circadian system in photoperiodic time measurement in the european corn borer, ostrinia nubilalis. larvae raised in a light-dark (ld) cycle consisting of 12 hr of light alternating with 12 hr of darkness (ld 12:12), at a constant temperature of 30 degrees c, enter a state of arrested growth and development known as diapause (takeda and skopik, 1985). in the present research (experiment 1), the indu ...	1986	2979587
photoperiodism in ostrinia nubilalis: a new protocol for the analysis of the role of the circadian system.	a 12-hr dark period, at a temperature high enough to permit time measurement to occur, is necessary for maximal induction of larval diapause in the european corn borer, ostrinia nubilalis. in the present study, induction of diapause only occurred in a periodic environment. this was in the form of certain (1) light-dark (ld) cycles at a constant temperature; (2) thermoperiods in constant darkness (dd), but not constant illumination (ll); and (3) ld cycles with concurrent thermoperiods. a light-br ...	1986	2979580
photoperiodic control of diapause induction and termination in ostrinia nubilalis: two different clocks?	both diapause induction and diapause termination are under photoperiodic control in the lepidopteran, ostrinia nubilalis. in the present study, induction of diapause was maximal in light-dark (ld) cycles that contained 12 hr of light alternating with 12 hr of darkness (ld 12:12). termination of diapause was maximal in ld 16:8. diapause termination also occurred rapidly in non-24-hr ld cycles that possessed an 8-hr dark phase. in each of these cases, the period of the ld cycle was not important. ...	1986	2979579
[use of baculovector for the expression of hbsag gene in insect cells].	based on the information of molecular biology of autographa californica nuclear polyhedrosis virus (acnpv), a recombinant transfer plasmid pacmv was constructed by molecular procedures included using two synthetic localized probes, which provided an inserted position linked with bamhi sequences nearly at polyhedrin initiating atg codon. then an expression vector pacmv-hbsag was reconstructed, it contained hbsag gene from subclone pypss-1 derived from adwserotype of hbv. the recombinant virus con ...	1989	2800542
no linkage between genes controlling female pheromone production and male pheromone response in the european corn borer, ostrinia nubilalis hübner (lepidoptera; pyralidae).	the e and z pheromonal strains of the european corn borer, ostrinia nubilalis, are characterized by female production of and male preference for opposite blends of (e)-11-and (z)-11-tetradecenyl acetate. it is known that the pheromone production is controlled by an autosomal gene and that the males' behavior is determined by a sex-linked gene. a third gene, autosomally inherited, has been shown to determine the organization of the male pheromone receptors. in the present study the linkage relati ...	1989	2599367
sprayable self-encapsulating starch formulations for bacillus thuringiensis.	under glasshouse conditions, various cornstarches and adjuvants were examined as encapsulating agents in sprayable formulations for bacillus thuringiensis subsp. kurstaki berliner. when these materials were suspended in water and tested for physical factors such as viscosity, clumping, and retention on plant surfaces, a range of responses was observed. all formulations tested had acceptable viscosity, but some formulations clumped. when applied to cotton leaves, certain formulations remained les ...	1990	2258512
electrophoretic characterization of chromosomal dna from two microsporidia.	spores of two microsporidia, nosema pyrausta (from the european corn borer, ostrinia nubilalis) and n. furnacalis (from the asian corn borer, o. furnacalis) were harvested from laboratory-reared o. nubilalis caterpillars and purified by centrifugation through percoll. conditions permitting in vitro germination were defined for both species and found to be different. n. pyrausta spores were incubated in 0.1 n koh for 30 min, recovered by centrifugation, and resuspended in 1 ml of an equal mixture ...	1990	2125628
isolation and characterization of a novel insecticidal crystal protein gene from bacillus thuringiensis subsp. aizawai.	bacillus thuringiensis subsp. aizawai eg6346, a novel grain dust isolate, was analyzed by southern blot hybridization for its insecticidal crystal protein (icp) gene profile. strain eg6346 lacks previously characterized cryia icp genes yet does possess novel cryi-related gene sequences. a recombinant genomic plasmid library was constructed for strain eg6346 in escherichia coli. one recombinant plasmid, peg640, isolated from the library contained a novel icp gene on a 5.7-kb sau3a insert. the seq ...	1991	2061280
limonoid antifeedants from seed of sandoricum koetjape.	an extract of the seed of sandoricum koetjape has yielded two new limonoids, sandoricin [1] and 6-hydroxysandoricin [2]. both compounds are effective antifeedants when incorporated into artificial diets and fed to fall armyworm (spodoptera frugiperda) or european corn borer (ostrina nubilalis) larvae. reduced growth rates and increased times to pupation were evident at lower dose levels while significant mortality was noted at higher dose levels. structures of both compounds were determined by 1 ...	1991	2045819
insecticidal toxins from bacillus thuringiensis subsp. kenyae: gene cloning and characterization and comparison with b. thuringiensis subsp. kurstaki cryia(c) toxins.	genes encoding insecticidal crystal proteins were cloned from three strains of bacillus thuringiensis subsp. kenyae and two strains of b. thuringiensis subsp. kurstaki. characterization of the b. thuringiensis subsp. kenyae toxin genes showed that they are most closely related to cryia(c) from b. thuringiensis subsp. kurstaki. the cloned genes were introduced into bacillus host strains, and the spectra of insecticidal activities of each cry protein were determined for six pest lepidopteran insec ...	1991	2014985
dithyreanitrile: an unusual insect antifeedant from dithyrea wislizenii.	dithyreanitrile, a novel sulfur-containing indole alkaloid, was isolated from the seeds of dithyrea wislizenii (cruciferae). dithyreanitrile inhibits feeding of fall armyworm (spodoptera frugiperda) and european corn borer (ostrinia nubilalis) larvae. dithyreanitrile, the first natural product with two sulfur atoms and a nitrile attached to the same carbon, was characterized by x-ray diffraction, spectroscopy, and chemical synthesis.	1991	2009944
structural and functional changes associated with cyanogen bromide treatment of wheat germ agglutinin.	the lectin, wheat germ agglutinin (wga), has been shown to have a significant larvicidal effect on the european corn borer, a major insect pest of corn. in order to characterize this toxic effect, we have undertaken structure-function studies on wga. to this extent, the effect of cyanogen bromide (cnbr) on the conformation, subunit interactions, and biological activity of wga has been investigated. the cnbr-modified lectin exhibits no toxicity to the ecb, cannot dimerize, does not bind to n-acet ...	1991	1898037
isolation of high-molecular-weight dna from insects.	a simple and rapid method for the isolation of high-molecular-weight dna from insects is described. the method does not require cscl ultracentrifugation or extensive dialysis. high-molecular-weight dna was obtained within 24 h. since the entire insect was used for dna isolation, an initial nuclei-enriched fraction was required. genomic dna was extracted from lysed nuclei by organic phase separation (liquid/liquid extraction). this method has been successfully applied to the isolation and purific ...	1990	1693047
sexual dimorphism of tarsal receptors and sensory equipment of the ovipositor in the european corn borer, ostrinia nubilalis.	sensilla on legs and ovipositor of the moth ostrinia nubilalis were investigated by light and scanning electron microscopy. the ovipositor is composed of two papillae densely packed with medium length mechanoreceptor sensilla (mrb: 80-160 microns, n = 420-460). long mechanoreceptor sensilla (mra: 250-300 microns, n = 20-24) and contact chemoreceptors (cra: 30-40 microns, n = 20-28) are evenly distributed at the periphery of these papillae. legs support contact chemoreceptors (cra), scattered amo ...	1992	1571964
insect photoperiodism: the "t experiment" as evidence for an hourglass mechanism.	"t experiments" demonstrate that the clock controlling termination of larval diapause in ostrinia nubilalis is an hourglass mechanism that measures 8 hours of darkness. circadian oscillations are not involved in photoperiodic time measurement in this species.	1976	1257756
aspergilus flavus and aflatoxin in iowa corn before harvest.	aspergillus flavus and aflatoxin were detected in ears of iowa corn on plants before harvest in 1975. presence of the fungus was associated with kernel injury caused by the second generation european corn borer. amounts of aflatoxin b1 in corn from a limited number of selected ears ranged from 1 part per billion to 1560 parts per billion with a mean of 430 parts per billion.	1976	821144
[the effect of continuous rearing on an artificial diet on the physiology of a lepidopteran, ostrinia nubilalis hübner].	rearing on an artificial diet during 20 successive generations had important consequences on the physiology of a lepidopteran, ostrinia nubilalis hbn. this laboratory strain was found less virulent than the one from nature. if the causes of this weakness can be of genetic as well as of pathological origin, it is probable that such strains cannot be utilized, without risk, in the studies on resistance of maize lines.	1976	816540
role of phermones and kairmones for insect suppression systems and their possible health and environmental impacts.	insects produce pheromones as a chemical communication system to facilitate reproduction. these highly active chemical attractants have been synthesized for some of the most important insect pests, including the boll weevil, gypsy moth, codling moth, tobacco budworm, european corn borer, and several bark beetles. while none of the synthetic sex attractants have yet been developed for use in insect control, they offer opportunities for the future both as control agents and to greatly improved ins ...	1976	789061
a bioassay for plant-derived pest control agents using the european corn borer.		1979	528746
recent research advances on the european corn borer in north america.		1975	234710
ammonium sulfate activation of phosphodiesterase in homogenates of larvae of the european corn borer.	european corn borer phosphodiesterase is highly activated by (nh4)2so4 and moderately activated by nh4c1 (ph 7.6, 33 degrees). vertebrate and crayfish diesterases, on the other hand, are inhibited by (nh4)2so4. it is likely that (nh4)2so4 causes some configurational change in the european corn borer phosphodiesterase molecule which results in the exposure of more active sites and hence greater enzyme activity. in in vitro tests caffeine (0.008 m) and theophylline (0.008 m) inhibit phosphodiester ...	1976	180541
comparative ultrastructure and blood-brain barrier in diapause and nondiapause larvae of the european corn borer ostrinia nubilalis (hübner).	ultrastructural examination of diapause and nondiapause larval brains of the european corn borer disclosed anatomical differences that may be related to the insect's "blood-barrier". the perineurial type i cells are quite closely appressed in the diapause brain, but thrown into extensive folds with large intercellular spaces in the nondiapause brain. the perineurial type ii cells of diapause and nondiapause larvae are basically similar in general ultrastructure, and most likely form the basis fo ...	1975	126807
distribution of putative neurotransmitters in the brain of the european corn borer, ostrinia nubilalis.		1977	22570