Honey Bee Races Research Articles

Circadian rhythms in honeybees: entrainment by feeding cycles

ABSTRACT. Colonies of the South African honeybee race Apis mellifera capensis (Escholtz) were maintained under constant conditions of illumination (200 lux), temperature (25±ld̀C) and relative humidity (65±3%). Activity was measured at the hive entrance. After ad libitum feeding for at least 5 days, food was presented for only 2 h/day either for 1 week (series 1) or for 2 weeks (series 2). In the last part of each experiment, food was again available all the time. Colonies which showed free‐running circadian activity rhythms (with periods ranging from 22.6 to 24.8 h) during ad libitum feeding were submitted to feeding cycles with inter‐feeding intervals (T) of 22, 23, 24 and 25 h. In most of these experiments the rhythms were synchronized by the feeding schedule, resulting in a stable phase‐angle difference between onset of activity and onset of food availability. The duration of this anticipatory activity was positively correlated with T. When ad libitum feeding was resumed, the period of the rhythm induced by the feeding schedule persisted for a few days. Thereafter, the rhythm was free‐running again with a period close to that observed in the first part of the experiment. The conclusion is drawn that, under the influence of periodic feeding, the activity of honeybee colonies has the characteristics of an entrained circadian system.

Investigation of cuticular hydrocarbons from selected honeybee populations by gas chromatography with pattern recognition

Hydrocarbon type substances were extracted from the surface of three subspecies of the honeybee race Apis mellifera and analyzed by capillary column gas chromatography. The reproducibility of various extraction methods was investigated. Emphasis was placed on the quantitative assessment of changes in the gas chromatographic profiles. Soxhlet extraction with toluene produced slightly larger amounts of high-molecular-weight hydrocarbons than washings with n-hexane. Differences between freeze dried, air dried, and fresh specimen were minimal. The hydrocarbon content of bees, stored at ambient temperature decreased with time but the patterns did not change significantly. A reproducibility study showed that differences in the chromatographic profiles of bees from the same colony were small. Bees collected over a wide geographic area produced larger variations. Bees from the European and African subspecies and their hybrid, the so-called Africanized bee, produced very characteristic profiles. The data were subjected to computerized pattern recognition, based on the chemometrics package ARTHUR. The three subspecies examined were the European honeybee, the African honeybee and an Africanized hybrid originating from Panama. The subspecies can easily be distinguished from each other by their characteristic chromatographic profiles. Only three components are needed to carry out reliable classification. It was found that the K-nearest neighbor algorithm provides the best classification potential.

Differential Reproduction of the Mite, Varroa jacobsoni (Mesostigmata: Varroidae), on Africanized and European Honey Bees (Hymenoptera: Apidae)

Recent surveys of honey bee colony mortality due to the external parasite Varroa jacobsoni (Oudemans) suggest that the virulence of this mite pest may be affected by climate or honey bee race. The latter possibility was tested by examining the effect of varroa infestation on colonies of Africanized and European bees in Brazil. Infestation of varroa on colonies of both bees was similar, but there were significant differences between percentages of mites that reproduced. In European bee colonies, 75% of infested brood cells had immature mites compared with only 49% of infested brood cells in colonies of Africanized bees. Decreased rate of varroa reproduction on Africanized honey bee worker brood is one factor contributing to reduction of virulence of varroa in Africanized bee colonies. The role of a second factor, length of honey bee pupal state, also is discussed. Honey bee race rather than differences in climate appears to play a crucial role in resistance to varroa.

Events following queen removal in colonies of european-derived honey bee races (Apis mellifera)

The timing of queen rearing and swarming are described after queens were removed from colonies of European-derived honey bee races. Queen cell construction began within one day of queen loss, and 91 % of the queens which emerged were eggs at the time of queen loss. Queen cells were evenly distributed over the comb face, and 4 % of the brood reared as queens were moved from worker cells to queen cups. There was considerable variation in the number of queen cells which were viable, aborted, and unoccupied. Brood mortality was high following queen loss. Six of the eight study colonies swarmed following the emergence of a virgin queen. These results differ from previous studies of queen loss in tropically-evolved honey bees in the timing of new queen production and the frequency of queen-loss swarming and of brood movement by workers.

Demography and life history characteristics of two honey bee races (Apis mellifera).

Intra-colony demography and life history characteristics of neotropical Africanized and temperate European honey bearaces were compared under simulated feral conditions. Major differences in colony demography were found which nevertheless resulted in some similar reproductive characteristics. European colonies were larger than Africanized colonies, had more rapid initral growth rates of worker populations, showed better survivorship of brood and adult workers, and differed in patterns of worker age distribution. However, both races were similar in the brood and adult populations when colonies swarmed, the frequency and timing of swarming, and the number of workers in prime swarms. The factors most important in determining these colony growth and reproductive patterns were likely worker mortality rates, climate, and resource availability.

Blood Sugar Levels in Worker Honeybees of Different Races as an Index of Their Honey Production

SummaryPositive correlations were found between net honey production and blood sugar levels in foraging workers of different honeybee races and hybrids. The highest correlation coefficient (+0·887) was found for glucose, followed by fructose (+0·832) and trehalose (+0·697). Levels of trehalose, unlike those of the hexoses, did not show effects of heterosis in triple hybrids.

Swarming, afterswarming, and reproductive rate of unmanaged honeybee colonies (Apis mellifera)

The reproductive rate of unmanaged European honeybee races was studied in Kansas, U.S.A. Colonies produced a mean of 3.6 daughter colonies per original queen during one year. This high reproductive rate was largely due to the frequent occurrence of afterswarms, a factor not adequately considered in previous studies. The rate of afterswarming was influenced by at least two factors: the amount of sealed brood (pupae) in the colony and the season when swarming occurred. Factors which may influence the survival and subsequent reproduction of prime swarms and afterswarms are discussed.

Population Genetic Studies on Sex Alleles in the Honeybee Using the Example of the Kangaroo Island Bee Sanctuary

SummaryThe common practice of crossing different races of honeybees has created a demand for the establishment of isolated reserves for pure ecotypes of the main races. On Kangaroo Island, S. Australia, a bee sanctuary 100 years old, the average survival rate of brood was found to be 75.6%. Mortality of 6.5% was caused by factors other than sex alleles, so the survival rate resulting from sex alleles was 82.1%.Equations are presented for calculation of survival rate of brood (S) in populations in equilibrium, S = (N-1)/N, and in unstable populations, S-1-pf pm-qfqm-rfrm…. Equations are developed for calculating the frequencies of sex alleles in subsequent generations, and after the introduction of new alleles (and new queens), and also differences between the frequencies of sex alleles in the two sexes.In natural selection, sex alleles in honeybees represent an example of overdominance, with total elimination of all homozygotes in populations with multiple alleles and different frequencies of those alleles in the sexes.Calculations show that 36% of the drones that mated with the queens in the sanctuary carried the same sex alleles as the queens.Only 6 of 12 sex alleles known to occur in the honeybee were present among the bees in the sanctuary. An increase in the number of alleles above 8–10 in a population gives very little improvement in the percentage of surviving larvae. Theoretical calculations shows that the frequencies of different sex alleles must be equal throughout the bee population on Kangaroo Island. When a new allele is introduced into a population with few alleles, even in a very low proportion, its frequency increases rapidly, and thus the survival of brood increases. The maximum survival rate of brood in a population is reached when the sex alleles are in equilibrium. Before reaching equilibrium for different sex alleles, any generation of queens produces virgins and drones with different frequencies of these alleles. When there are few alleles, there is a diminishing oscillation in the frequency of the same sex allele between the two sexes, in subsequent generations. The best way to increase the number of sex alleles in a population and to increase the survival of brood, with a minimal change of other characters, is to introduce one or very few queens inseminated by several (not many) different drones.Although the survival rate of brood on Kangaroo Island was rather low, after 100 years of isolation, the colonies were still good honey producers.

A Bioassay for Determining Honey Bee Responses to Flower Volatiles 1

A test arena was designed for determining the responses of Apis mellifera L. to components of scent gland pheromone and flower volatiles of alfalfa, Medicago sativa L. Bees that had been conditioned to associate the odor of citral, geraniol, ocimene, myrcene, limonene, or linalool with availability of sucrose solution consistently selected the conditioning chemical. Also, bees conditioned to forage with the odor of ocimene responded to alfalfa flower aroma, the percentage of positive responses changing during the day as the amount of volatiles produced increased and decreased. Both Italian and Caucasian races of honey bees, when conditioned with ocimene, responded to volatiles of alfalfa flowers.

Quantitative immunochemical and electrophoretic comparisons of glycerophosphate dehydrogenases in several insects

An immunochemical method, micro-complement fixation, has been used to compare quantitatively DPN +-dependent glycerophosphate dehydrogenases (EC 1.1.1.8) of various insects. Rabbit antibodies directed against pure honeybee glycerophosphate dehydrogenase were prepared, and the cross-reaction with extracts of other insects measured. The order of decreasing cross-reaction is: honeybee, bumblebee, robust mining bee, leaf-cutting bee, sphecoid wasp, yellow jacket, syrphid, and flesh fly; this is the same as the classical taxonomic order. Several other insects apart from the Hymenoptera show no detectable cross-reaction; the enzymes from six honeybee races and the three honeybee social orders possess identical immunological properties. The specific activity of glycerophosphate dehydrogenase in honeybee thoracic muscle increases fivefold during the week following adult emergence. The immunological properties of the enzyme are identical in the newly emerged and 6-day-old bees. Thus the change in enzyme activity is apparently due to an increase in the number of enzyme molecules. Electrophoretograms show that most of the insects studied here have more than one band with glycerophosphate dehydrogenase activity. There is, however, no obvious taxonomic relationship between the electrophoretic patterns of these insects.

Preferences of Two Races of Honey Bees for Selected Alfalfa Clones Under Competitive and Noncompetitive Foraging1

In alfalfa the clonal preferences of Golden Italian, Apis Mellifera liguslica Spinola, and Carniolan, Apis mellitera carnica Pollmann, honey bees (chosen because of similarity in behavior and difference in color) were similar when they foraged alone in a cage during June and August 1965 at Manhattan, Kansas. Similarly, the parallelism of the clonal preferences of the 2 bee races, when foraging together in the cage, were striking. Equality of clonal attractiveness in field and cage was demonstrated for the 25 clones used. Preferences of neither honey bee race were appreciably altered by equalizing racemes per plant. The bee races appeared to compete for clones in foraging, but the effect on individuals of each race was about equal. Carniolans caged alone appeared to be more efficient pollinators of alfalfa than Golden Italians.

Heterosis in the Honey Bee as Shown by Morphological Characters in Inbred and Hybrid Bees

Inbred queens from eight lines representing several races of honey bees (Apis mellifera L.) were mated (artificially inseminated) to drones of the same line and also to another line, so that inbred and hybrid worker offspring were produced simultaneously from each mother queen. By the use of genetic markers the two types of offspring were identifiable. Small but highly significant differences between lines were found in the characteristics length, wing width, cubital index, number of wing hooks, tongue length, and antenna lengths. The hybrid bees were usually larger than their inbred sisters. This difference in size suggests that hybrid vigor is present in honey bees. Uncontrollable feeding variability between colonies apparently accounted for significant differences in some samples.

The Races of Honeybees in Africa

The Races of Honeybees in Africa

Biometrical Investigation of some European and other Races of Honeybees

(1955). Biometrical Investigation of some European and other Races of Honeybees. Bee World: Vol. 36, No. 3, pp. 41-45.

Observations on Resistance of Some Dark Races of Honeybees to European Foulbrood

Observations on Resistance of Some Dark Races of Honeybees to European Foulbrood

A Short Note on the Races of Honey Bees in Tanganyika Territory

"A Short Note on the Races of Honey Bees in Tanganyika Territory." Bee World, 12(8), pp. 90–91

Seasonal brood-Rearing Activity of the cyprian Honeybee

The seasonal brood-rearing activity of a colony of Cyprian honeybees proved on investigation to be strikingly similar to that typical of colonies of Italian honeybees in the same apiary. Furthermore, this colony exhibited no tendency to tolerate laying worker-bees while it had a laying queenbee, nor did it build more queencells than did Italian colonies in the same apiary at the same time. Its queenbee gave no evidence that her race was any more prolific than the Italian race of honeybee.