H. Allen Sylvester

Polyandry in the genus Apis, particularly Apis andreniformis

Abstract Using four polymorphic microsatellite loci, we found that four Apis andreniformis queens collected in Thailand each mated at least 10–20 times, producing an average relatedness, gww, of workers of 0.30 ± 0.007, and an average effective number of matings of 9.1 ± 2.2. The degrees of polyandry and intra-colonial genetic relatedness in A. andreniformis are similar to those in A. mellifera, slightly more than in A. florea, and up to 6 times less than in A. dorsata. We argue that while presently favoured hypotheses for the evolution of polyandry in monogynous social insects may adequately explain the evolution of up to five or six matings, they are inadequate to explain the extreme polyandry (10–60 matings) observed in Apis. One alternative possibility is that colony fitness is a non-additive function of the fitness of individual subfamilies. Such behavioral over-dominance may mean that queen fitness is increased by high levels of polyandry, which increase the probability of desirable combinations of worker genotypes occurring in one colony. The special attributes of honey bees which may lead to behavioral over-dominance include colony aggregation (which may increase the incidence of disease), and frequent long-distance migration.

Task specialization in a wild bee, Apis florea (Hymenoptera: Apidae), revealed by RFLP banding

Workers in a wild in situ colony of the dwarf honey bee, Apis florea, were observed undertaking the following behavior: liquid foraging, pollen foraging, guarding, stinging, fanning and wagging abdomen. Bees of each behavioral class were separately collected and frozen. Collections were made over a period of 10 days. Random samples of brood and workers were also collected. DNA was extracted from each bee and “fingerprinted” using a probe of unknown sequence obtained from an A. mellifera genomic library. Patterns of fingerprints (Fig. 1) were dissimilar among behavioral classes (Tables 1 and 2), strongly suggesting a genetic component to division of labor in this species. This result supports similar findings in A. mellifera in a species that is not troubled by many of the experimental difficulties inherent in A. mellifera.

Time of drone flight in four honey bee species in south-eastern Thailand

SUMMARYAt Chanthaburi, Thailand, four species of Apis, A. andreniformis, A. florea, A. cerana and A. dorsata, are sympatric. Observations were carried out on three wild colonies of each species on various days in February 1992. The daily drone flight periods were only partially specific: A. andreniformis from 12.15 h to 13.45 h; A. florea from 14.00 h to 16.45 h; A. cerana from 15.15 h to 17.30 h; and A dorsata from 18.15 h to 18.45 h. The significance of these partially separate drone flight periods is discussed in terms of both reproductive isolation and evolution.

Electrophoretic Identification of Africanized Honeybees

SummaryA procedure for analysing the results of protein electrophoresis for taxonomic purposes is described. Its application to identifying Africanized honeybees is presented, using previously reported data for the loci coding for malate dehydrogenase (Mdh), alcohol dehydrogenase (Adh), and a general protein band (P-3). Mdh can be used alone to identify individual workers as Africanized or European, with a probability of more than 90% for the reported populations, but it does not meet the 99% probability criterion for use as a diagnostic locus. When the reported results for all three loci are combined, individual Africanized or European workers should be identifiable with a probability of more than 99%. This degree of accuracy may not be possible in other populations, not yet assayed electrophoretically.

Comparative nest architecture of the dwarf honey bees

SUMMARYComplete descriptions using a variety of measurements are provided for nests of Apis andreniformis from south-eastern Thailand, Sichuan and Hunan Provinces of China, and Palawan, Philippines and Apis florea from southeastern Thailand and Hunan Province of China. Overall, the single-comb nest of A. andreniformis has a very different structure from that of A. florea. The comb built by A. andreniformis has a midrib both above and below the supporting branch. However, the comb built by A. florea has a mid-rib only in the brood area below the supporting branch. The honey storage mid-rib of A. andreniformis nests gives them a characteristic crown appearance. Other differences include the overall size of the nest, the width and depth of worker cells and the width of drone cells.

Morphometric studies of Apis cerana in Thailand and the Malaysian peninsula

SUMMARYSamples of Apis cerana were collected from 44 locations in 12 regions of Thailand and peninsular Malaysia. Morphometric measurements were made on 58 characters. Statistical analysis showed that these samples could be separated into four groups: northern to central Thailand, southern Thailand to the end of the Malaysian peninsula, Samui Island and, less distinctly, Phuket Island. These differences support the interpretation that A. cerana has spread its range into south-east Asia in recent geological times.

Functionality of Varroa-Resistant Honey Bees (Hymenoptera: Apidae) when used in Migratory Beekeeping for Crop Pollination

ABSTRACT Two types of honey bees, Apis mellifera L. (Hymenoptera: Apidae), bred for resistance to Varroa destructor Anderson & Trueman were evaluated for performance when used in migratory crop pollination. Colonies of Russian honey bees (RHB) and outcrossed bees with Varroa-sensitive hygiene (VSH) were managed without miticide treatments and compared with colonies of Italian honey bees that served as controls. Control colonies were managed as groups which either were treated twice each year against V. destructor (CT) or kept untreated (CU). Totals of 240 and 247 colonies were established initially for trials in 2008 and 2009, respectively. RHB and VSH colonies generally had adult and brood populations similar to those of the standard CT group regarding pollination requirements. For pollination of almonds [Prunus dulcis (Mill.) D.A.Webb] in February, percentages of colonies meeting the required six or more frames of adult bees were 57% (VSH), 56% (CT), 39% (RHB), and 34% (CU). RHB are known to have small colonies in early spring, but this can be overcome with appropriate feeding. For later pollination requirements in May to July, 94–100% of colonies in the four groups met pollination size requirements for apples (Malus domestica Borkh.), cranberries (Vaccinium macrocarpon Aiton), and lowbush blueberries (Vaccinium angustifolium Aiton). Infestations with V. destructor usually were lowest in CT colonies and tended to be lower in VSH colonies than in RHB and CU colonies. This study demonstrates that bees with the VSH trait and pure RHB offer alternatives for beekeepers to use for commercial crop pollination while reducing reliance on miticides. The high frequency of queen loss (only approximately one fourth of original queens survived each year) suggests that frequent requeening is necessary to maintain desired genetics.

Association of single nucleotide polymorphisms to resistance to chalkbrood in Apis mellifera

Summary Chalkbrood is a honey bee brood disease that often affects colonies that are already under stress. Control of the disease can be as simple as ensuring adequate ventilation and food sources or using clean beekeeping equipment. When the infection goes unchecked, however, the overall health and productivity of the colony is greatly decreased. Some strains of honey bees seem to be more troubled by the disease than others. Efforts to control rampant infections have not been widely accepted or successful. Identifying a genetic basis for resistance in the affected larvae would be useful for breeding for improved resistance in bee populations. We here show a statistically significant association between larval chalkbrood resistance and a genomic locus. Selective breeding for larval resistance can probably work in concert with breeding for desirable characteristics such that chalkbrood can become a negligible disease among managed colonies.

Patterns of Apis mellifera infestation by Nosema ceranae support the parasite hypothesis for the evolution of extreme polyandry in eusocial insects

We investigated the relationship between infestation levels of Nosema ceranae and patriline membership by sampling individual worker bees from five colonies from both Russian and Italian lineages. Individual workers were tested for N. ceranae infestation level using qPCR, and then genotyped to determine their patriline membership. Levels of N. ceranae infestation differed significantly between lineages and colonies for both Russian and Italian workers. Patriline-based variance was evident only among the Russian workers. There was substantial variation in N. ceranae levels among Italian workers, ranging from 0 to 2 × 109Nosema/bee, but this variation was unrelated to patriline membership. The results for Russian honey bees are congruent with predictions derived from the parasite hypothesis for the evolution of polyandry–patrilinial variance in parasite tolerance contributes to colony level resistance by reducing the probability of catastrophic failure that might occur if a colony was genetically homogeneous.

Multivariate morphometric study of Apis florea in Thailand

SUMMARY Morphometric analyses of Apis florea in Thailand were carried out in order to detect differences within this species. The nine body parts selected for analysis were: proboscis, antenna, forewing, hindwing, hind leg, the third and sixth sternites, and the third and fourth tergites. Twenty-two characters, consisting of widths, lengths or angles, were measured. Factor analysis sorted 14 characters of worker bees into four factors: (Factor 1) characters associated with size, hind leg and antenna; (Factor 2) length of wing venation and forewing; (Factor 3) number of hamuli and venation angle 37; and (Factor 4) venation angle 34. The results of factor and cluster analyses using the 22 characters revealed that the A. florea of Thailand are distributed as one group. Four characters (forewing radial cell length, metatarsus length, 3rd sternite length and antenna length) can be used to separate by Student-Newman-Keuls Statistics the A. florea of Samui and Pha-ngan Islands from the mainland.