ABSTRACT. Copulatory responses to a variety of decoy objects baited with synthetic 15,19,23‐trimethylheptatriacontane were induced in adult male Glossina morsitans morsitans Westw., provided the object was of similar shape and size to a female fly. Chemical and configurational (shape and texture) stimuli were important in eliciting and maintaining copulatory behaviour of males. A dose/response relationship was obtained from 7‐day‐old test males, with an ED 95 of 2 μg using as decoys solvent‐washed dead males baited with 15,19,23‐trimethylheptatriacontane. The quantity of this compound in 5‐day‐old adult females is more than 4.0 μg; in males, only 0.6 μg. It is considered to have the characteristics of a true contact sex pheromone for the species, and does not act synergistically with other less stimulatory synthetic compounds. Gas chromatographic analysis of adult female cuticular paraffins of G.m.morsitans showed the presence of two large peaks between C 37 and C 38 which were virtually absent in males. Young adults of both sexes possessed a series of hydrocarbons below C 29 which disappeared during the first few days of adult life. The natural pheromone appears on the pharate adult female about 2 days before emergence from the puparium and is present throughout life. This suggests it is a component of the surface cuticular waxes. Responsiveness of males to pheromone‐baited decoys increased to a maximum 3–4 days after emergence in regularly fed flies and only declined during the 24 h prior to death from starvation.

Abstract Endocrine‐and age‐related changes in metabolite contents were used as a measure of fat body development and function in adult male Blaberus discoidalis cockroaches. Fat body dry weight, protein, glycogen, and lipid levels coordinately decreased at days two to three of adult life, increased at day four, then declined to lower stable levels by days six to seven. The metabolite contents remained stable from days seven through ten and were still at this level on day 30. Long‐term endocrine deficiencies resulting from corpora cardiaca‐allata extirpation did not change the amounts of metabolites present at 30 days of age. The fat body DNA content remained constant regardless of age or endocrine balance. Unlike other metabolites, the RNA content increased to twice its original level during the first six days of adult life and was unaffected by either age or endocrine balance thereafter. The findings suggest that the adult fat body changes from a storage function at the time of the nymphal‐adult molt to a biosynthetic function by day six. The transition is independent of endocrine control by the corpora cardiaca‐allata complex.

Journal Article Bionomics of Euplectrus puttleri, new species, an Introduced Parasite of the Velvetbean Caterpillar, Anticarsia gemmatalis from South America Get access Benjamin Puttler, Benjamin Puttler 4Biological Control of Insects Research Unit, Agric. Res. SEA, USDA, Columbia, MO 65205 Search for other works by this author on: Oxford Academic Google Scholar Gordon Gordh, Gordon Gordh 5Formerly with Systematic Entomology Laboratory, Agric. Res., SEA, USDA, Washington, DC 20560, now with Div. of Biol. Control. Dept. of Entomology, Univ. of Calif., Riverside 92521 Search for other works by this author on: Oxford Academic Google Scholar S. H. Long S. H. Long 4Biological Control of Insects Research Unit, Agric. Res. SEA, USDA, Columbia, MO 65205 Search for other works by this author on: Oxford Academic Google Scholar Annals of the Entomological Society of America, Volume 73, Issue 1, 15 January 1980, Pages 28–35, https://doi.org/10.1093/aesa/73.1.28 Published: 15 January 1980 Article history Received: 14 June 1979 Published: 15 January 1980

Differential decrease in protein synthesis by microsomes from aging Drosophila melanogaster

Age-related changes in the body composition of mated and unmated blowflies Phormia terrae novae

Diuresis and its hormonal control in butterflies

A reliable, widely adaptable capacitance discharge activity monitor for determining levels of insect activity is described. Sample activity patterns of a wild type stock of house flies maintained under a 16:8 LD photoperiod are given to illustrate the monitor's output. For the 1st 2 days of adult life, flies showed a pattern of increasing activity levels after which a bimodal diurnal pattern was established. Activity increased during the latter portion of the dark period until a peak was shown at the onset of lights. Mid-day activity levels were depressed but increased to a 2nd peak in the late afternoon. The use of the monitor in total darkness permitted the detection of the increasing activity levels during dark periods.

Food utilization and metabolic efficiency in larval and adult house crickets

Glucose oxidase and other enzymes of hydrogen peroxide metabolism from cuticle of Schistocerca americana gregaria

The wide range of reproductive capacities among different kinds of organisms, the many striking occurrences of evolutionary novelties which pertain to mating success, and the variety of genetic systems have provided the basis for many current discussions on patterns of reproduction. Furthermore, the preservation of rare and desirable species, and the control of common and noxious ones, often depends on our understanding of those factors which determine reproductive rates. In these discussions, it is generally recognized that reproduction is usually the major component of Darwinian fitness, and that the act of reproduction, through interaction with other components of fitness, entails some cost to the parental organisms; therefore, one can speak of evolutionary tactics which maximize the probability of successful transmission of genes to future generations (Stearns, 1976). Reproduction is correlated with both extrinsic environmental factors (food supply, tidal cycles, daylength, etc.) and components within the population (density, social and age structure, etc.). Viewed from this perspective, there are similarities between the salmon and the cicada, the smuts and trematodes, aphids and rotifers, and so on. Of particular interest is the phenomenon of reproductive compensation, in which iteroparous, or continuous, breeders have age-specific reproductive rates which vary with different conditions experienced throughout their lifespan, and for which the total reproductive output is so constrained that there is an inverse dependence between reproductive rates at different times in the lifespan. Mertz (1971) discusses the demographic consequences of variable reproductive rates over an individual's lifetime. Sonleitner (1961) had measured the oviposition rates of Tribolium castaneum beetles in high and low density populations; the lowdensity cohort had a higher rate early in its lifespan, and a lower rate late in life, than the high-density cohort. Beetles cultured at high density also had a longer lifespan. Mertz cites this reproductive pattern (which he called reproduction) as being advantageous for animals with long life spans and argues that under favorable conditions (such as low density) reproductive effort should be expended early in life, and conversely, reproduction should be deferred to late in life when a population is declining in numbers (e.g. under high density conditions). Replication in Sonleitner's experiment was low and the results partially confounded by differences in survivorship, and because the experiment was terminated after 99 days of adult life, it was not possible to estimate the total reproduction over the beetles' lifespan. Most importantly, this experiment left unanswered the question of the effect of exposure to different densities at one stage of reproduction on subsequent oviposition rates when the beetles are brought into the same environment. To answer this last question, I (Boyer, 1976) measured the effects of different prior environment treatments (in which age-structure, nutritional content of the medium, density, and presence/absence of a competitor species were the variables) imposed on larvae or young adults of Tribolium castaneum. The beetles later were removed from these treatments and their oviposition rates measured under identical conditions. I found that old beetles tended to have higher reproductive rates if their earlier reproduction had been lower than

Observations of boll weevil midgut when fed natural food or on bacterially contaminated artificial diet

Endocrine control by neurosecretory cells of the pars intercerebralis and the corpora allata during the earlier phases of vitellogenesis in Locusta migratoria migratorioides R and F ( Orthoptera)

Abstract In Drosophila melanogaster, about a thousand larval fat body cells survive metamorphosis, but histolyze and disappear in the first few days of adult life. We wondered what hormonal factors control larval fat cell disappearance in normal and mutant flies. In order to test the effect of anterior endocrine organs, we isolated abdomens from the head and thorax of newly eclosed flies. In isolated abdomens fat cells disappeared at a much slower rate, decreasing by only 30% instead of 100% by 72 hours. To find if the juvenile hormone was responsible for this result, we treated isolated abdomens with ZR‐515, a juvenile hormone analogue. In ZR‐515 treated isolated abdomens, the fat cell number decreased by 94% at 72 hours. This shows that juvenile hormone activity can replace the lytic factor missing from isolated abdomens. The mutation ap4 retards the rate of fat cell lysis: only 47% of the cells disappear by 48 hours compared to 99% in heterozygous controls. To find if JH activity could restore the normal phenotype, we treated these mutants with ZR‐515. The result was that hormonetreated mutants at 48 hours had destroyed 88% of their fat cells, thereby approaching the normal situation. To study the effect of an inhibitor of protein synthesis, we injected cycloheximide into freshly eclosed normal flies. A dose of 0.3 μl of 6 × 10−4 gm/ml cycloheximide inhibited both vitellogenesis and larval fat cell disappearance. This inhibition could not be overcome by administration of ZR‐515. From these studies we conclude that juvenile hormone activity is required for larval fat cell disappearance in both wild type and mutant flies. Since cycloheximide inhibits larval fat cell disappearance even in the presence of a juvenile hormone analogue, it is suggested that the lytic effect of juvenile hormone is mediated via protein synthesis.

1. Ca2+ transport by mitochondria isolated from flight muscle of the sheep blowfly Lucilla cuprina does not occur in the absence of added P1. Maximum rates of transport are attained when about 2.5 mM-phosphate is present. 2. As mitochondria develop, high but not low phosphate concentrations begin to inhibit Ca2+ transport markedly; those isolated from 2-day-old flies for example, are inhibited by about 75% by 20 mM-phosphate. Maximum rates of transport, i.e. those measured in the presence of 2.5 mM-phosphate, begin to decline only when the fly is about 3 days old. 3. Mitochondrial phosphate transport activity does not change during development of the blowfly, but the endogenous concentration of the anion does. At emergence it is about 6nmol/mg of protein, increases to about 17 nmol/mg of protein at 2-3h and then rapidly declines to reach less than 5 nmol/mg of protein after 2 days of adult life. 4. Studies on the effect of phosphate on oxidation of alpha-glycerophosphate in the absence and presence of ADP reveal a lack of inhibition by high phosphate concentrations indicating that the anion does not influence Ca2+ transport by preventing the generation of the proton electrochemical gradient across the inner membrane. 5. It is concluded that the molecular assembly in the inner membrane of Lucilla mitochondria responsible for transporting Ca2+ is fully developed at emergence and remains so for at least 2-3 days of adult life. The possibility exists that Ca2+-transport activity in these mitochondria is controlled at least in part by P1.

Studies on the regulation of the juvenile hormone titre in bumblebee workers, Bombus terrestris

Abstract Neurosecretory A cells in the pars intercerebralis of O. fasciatus were identified at the ultrastructural level. Fine structural study of the A cells of female insects during the period of production of the first batch of eggs revealed that these cells undergo qualitative and quantitative changes during the first eight days of adult life. The A cells appear to be inactive in the newly emerged females. There is a significant depletion of neurosecretory granules (NSG) in the perikarya in the 2‐day‐old females followed by an increase and decrease in the 4‐ and 6‐day‐old females, respectively. The A cells in the 8‐day‐old females showed an accumulation of NSG. The mitochondrial population increases after adult emergence reaching a peak in the 4‐day‐old females, and then declines gradually in the subsequent age groups. The effect of sublethal dose of gamma radiation on the ultrastructure of the A cells was also investigated. Radiation damage is evident as early as four hours after irradiation with 10 kR. There is considerable swelling of the lysosomes and the membrane system in the A cells of irradiated insects. Synthetic activity of the A cells, based on the distribution of the endoplasmic reticulum, Golgi complex and mitochondria, as well as release of the NSG are apparently inhibited after irradiation. Radiation‐induced damage becomes more conspicuous as post‐irradiation interval increases. It is surmised that the damage to the A cells might have contributed at least in part, to the failure of yolk deposition in the irradiated insects.

The most favorable temperature for development and survival of the immature stages of a nondiapausing India strain of the pink bollworm, Pectinophora gossypiella (Saunders), reared on artificial diet in the laboratory was 26°C. At 32°C, duration of the developmental stages was significantly shorter than at lower temperatures, but larval mortality was high, and adults laid significantly fewer eggs. At 20 °C, development, survival and particularly fecundity, were adversely affected. The frequency of mating was highest (2.3 × / ♂) in pink bollworms reared at 26° and 32°C, but oviposition was greatly reduced by the latter temperature. At 26°C, the mean of eggs/♂ was 262; 90% of the total was laid during the 1st 18 days of adult life. Our results are compared with those obtained for other geographical strains.

ABSTRACT. In fifth instar nymphs of Locusta there is only a feeble adipokinetic response to extracts of corpora cardiaca. In fledglings, this poor response persists for a few days but then increases dramatically to reach a plateau by day 8. The response declines to almost zero as the locusts age beyond 35 days of adult life. This pattern of change in response is similar in both males and females but there are some differences in magnitude depending upon whether the response is measured as changes in haemolymph total lipid (vanillin‐positive material) or total diglyceride (gas liquid chromatography). The poor response to adipokinetic hormone in nymphs and newly fledged locusts is not a result of shortage of stored lipid in the fat body and cannot be improved by injection of extra hormone.

Lethality of venom sac extracts of the Oriental hornet ( Vespa orientalis) as related to ontogenesis

Natural selection for covariation in growth components in Tribolium castaneum