The Maturation of the Ovaries and the Relation between Weight and Maturity in Locusta migratoria migratorioides (R. & F.)

Biochemical Aspects of Juvenile Hormone Action in the Adult Locusta Migratoria by

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)

Nucleic acids, proteins, and tryptophan pyrrolase activity of the fat body of Schistocerca gregaria Försk. (Orthoptera) during ovarian maturation

To test the hypothesis that exposure to queen mandibular pheromone (QMP) modulates ecdysteroid production in adult worker honey bees, ecdysteroids were measured in hemolymph and other tissues of individual adult worker honey bees reared with or without QMP in cages and field colonies. Ecdysteroid titers were higher in caged workers exposed to QMP continuously from the first day of adult life than in workers reared without QMP. Statistical cluster analysis suggested the possibility that a subgroup of workers (“responders”) is more sensitive to QMP in this regard than other workers. In 12-day-old workers, ecdysteroid titers in workers reared in queenright (QR) colonies were similar to those observed in cages with QMP, but lower than those in queenless (QL) colonies. Differences in number of ovarioles or degree of ovarian activation did not correlate with hemolymph ecdysteroids. Previous studies have demonstrated ecdysteroids in hemolymph in very young adult workers and in workers in QL colonies; the present study indicates that production of ecdysteroids occurs in older adult worker honey bees in the absence of morphological signs of ovarian activation, with cage studies revealing a modulatory role for QMP masked in the complex environment of the hive.

Factors affecting female fecundity in the cowpea seed beetle, Callosobruchus maculatus (Coleoptera: Bruchidae)

Metabolism of glucose, trehalose, citrate, acetate, and palmitate by the male desert locust during adult development

Changes in enzymes associated with lipogenesis during development of the adult male desert locust

A structural and biochemical study on the effects of methoprene on flight muscle develoment in Locusta migratoria L.

A biochemical and structural study on the effects of methoprene on fat body development in Locusta migratoria L.

To determine the reproductive traits of Paraglenea fortunei, 26 pairs of adults were reared on Boehmeria nivea leaves and stems under constant conditions. The mean lengths of preoviposition and oviposition periods of females were 4.8 and 32.0 days, respectively. Females made a mean of 456.8 wounds on stems for oviposition over their lifespan. A mean of 0.603 eggs was deposited under the epidermis through an oviposition wound. The mean lifetime fecundity was 275.7 eggs with a great difference between 62 and 748. Standardized regression analysis showed that the oviposition period was twice as responsible for the difference in lifetime fecundity as the oviposition rate. Path analysis also showed that the elytral length as an indicator of body size had an effect on lifetime fecundity through the oviposition rate but not through the oviposition period. The number of ovarioles per female averaged 24.0 and did not correlate with the elytral length. Thus, body size is considered to be associated with the oviposition rate via egg productivity per ovariole. The relationships between body size, oviposition rate, and ovariole number are discussed in comparison with another cerambycid beetle, Semanotus japonicus, the oogenesis of which is completed with the resources stored at larval stage.

Food utilization and metabolic efficiency in larval and adult house crickets

Juvenile hormone synthesis as related to egg development in neotenic reproductives of the termite Reticulitermes flavipes, with observations on urates in the fat body

Body size is of primary interest to biologists because of its often positive correlation with fitness, in particular fecundity. The size-fecundity relationship is well established both within and among species. However, little is known about how the size-fecundity relationship differs among populations of the same species or whether it differs in response to environmental conditions experienced by a single population. This study examines the size-fecundity relationship in the pallid-winged grasshopper (Trimerotropis pallidipennis: Acrididae, Oedipodinae) among seven populations that extend along an aridity gradient in the southwestern United States. Results showed a positive relationship between body size of field-caught females and precipitation along the gradient, but only among those populations that receive less than 12 cm rainfall a year. There was a positive relationship between body size and the number of mature oocyte in the ovaries and with the number of hatchlings. Potential fecundity, measured as the number of ovarioles, was not correlated with body size in any analysis. All analyses showed that populations differ in their size-fecundity relationships. This relationship was also examined in laboratory conditions that mimic years of high,versus low, food abundance. Results indicate that across the whole aridity gradient, the size-fecundity relationship is largely a function of available resources. The populations at the xeric end of the gradient however, change their reproductive strategy in years of low food abundance and invest more into reproduction per unit size than they do in years of high food abundance. Together, these results caution against assuming, a priori, a positive relationship between size and fecundity; results indicate this relationship depends on the measure of fecundity used, that populations can differ in this relationship and that this relationship can change with changes in environmental conditions. Last, when examined among individuals, body size explained less than 20% of the variation in fecundity, suggesting that body size is not the main determinant of reproductive success in this species.

Juvenile hormone-dependent vitellogenin synthesis in Locusta migratoria fat body: Inducibility related to sex and stage

SUMMARYThe total amount of sap ingested by individual larvae and adult (apterous virgino‐parae) of Aphis fabae on field beans was estimated by adding the weights of honeydew excreted and of water lost by evaporation to increases in body weight during growth and to the weight of larvae born throughout the lives of the adult insects. The quantity of respiratory gases was ignored. Temperature and lighting were kept constant; air humidity was kept high to lessen evaporation, and air movements were eliminated. A machine was made to collect simultaneously the excreta of ten individual aphids to record their total daily excreta continuously from birth to death. Honeydew was also collected daily in mineral oil from other aphids of the same age on similar plants, to estimate the size of the droplets. The mean excretion rate was estimated from the product of the mean frequency of excretion and the mean size of the droplets. The reproductive rate, fecundity and length of reproductive and post‐reproductive life of the adult aphids were also recorded. The larva ingested about 3–5‐45 mg. of sap in a life of 7 days and the adult about 30 mg. during a reproductive life of 21 days; only about 10% was used for growth and reproduction.The excretion of the adult rose to a maximum of 30–40 drops per day on the third day of adult life and then declined, apparently because of changes within the aphid itself, for when the insects were transferred to fresh plants the excretion continued to decrease. The rate of feeding, which is about equal to the rate of excretion, therefore also decreased as the insect aged but its rate of reproduction remained fairly steady for about 16 days. The swelling of the abdomen and the slight increase in weight during the post‐reproductive life of about 2 weeks suggested that, although excretion had stopped, small amounts of sap continued to be ingested. The aphids ingested about the same amount of sap on two varieties of field bean but were significantly more fecund on one than on the other, a difference probably attributable to differences in the quality of the sap of the two varieties.