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Showing papers on "Varroa sensitive hygiene published in 2000"


Journal ArticleDOI
TL;DR: The results imply that the findings of past research on V. jacobsoni are applicable mostly to V. destructor, and will also influence quarantine protocols for bee mites, and may present new strategies for mite control.
Abstract: Varroa jacobsoni was first described as a natural ectoparasitic mite of the Eastern honeybee (Apis cerana) throughout Asia. It later switched host to the Western honeybee (A. mellifera) and has now become a serious pest of that bee worldwide. The studies reported here on genotypic, phenotypic and reproductive variation among V. jacobsoni infesting A. cerana throughout Asia demonstrate that V. jacobsoni is a complex of at least two different species. In a new classification V. jacobsoni is here redefined as encompassing nine haplotypes (mites with distinct mtDNA CO-I gene sequences) that infest A. cerana in the Malaysia–Indonesia region. Included is a Java haplotype, specimens of which were used to first describe V. jacobsoni at the beginning of this century. A new name, V. destructor n. sp., is given to six haplotypes that infest A. cerana on mainland Asia. Adult females of V. destructor are significantly larger and less spherical in shape than females of V. jacobsoni and they are also reproductively isolated from females of V. jacobsoni. The taxonomic positions of a further three unique haplotypes that infest A. cerana in the Philippines is uncertain and requires further study. Other studies reported here also show that only two of the 18 different haplotypes concealed within the complex of mites infesting A. cerana have become pests of A. mellifera worldwide. Both belong to V. destructor, and they are not V. jacobsoni. The most common is a Korea haplotype, so-called because it was also found parasitizing A. cerana in South Korea. It was identified on A. mellifera in Europe, the Middle East, Africa, Asia, and the Americas. Less common is a Japan/Thailand haplotype, so-called because it was also found parasitizing A. cerana in Japan and Thailand. It was identified on A. mellifera in Japan, Thailand and the Americas. Our results imply that the findings of past research on V. jacobsoni are applicable mostly to V. destructor. Our results will also influence quarantine protocols for bee mites, and may present new strategies for mite control.

815 citations


Journal ArticleDOI
TL;DR: The biology and damage of the three main pest species Acarapis woodi, Varroa jacobsoni, and Tropilaelaps clareae is reviewed, along with detection and control methods.
Abstract: The hive of the honey bee is a suitable habitat for diverse mites (Acari), including nonparasitic, omnivorous, and pollen-feeding species, and para- sites. The biology and damage of the three main pest species Acarapis woodi, Varroa jacobsoni, and Tropilaelaps clareae is reviewed, along with detection and control methods. The hypothesis that Acarapis woodiis a recently evolved species is rejected. Mite-associated bee pathologies (mostly viral) also cause increasing losses to apiaries. Future studies on bee mites are beset by three main problems: (a) The recent discovery of several new honey bee species and new bee-parasitizing mite species (along with the probability that several species are masquerading under the name Varroa jacob- soni) may bring about new bee-mite associations and increase damage to beekeeping; (b) methods for studying bee pathologies caused by viruses are still largely lacking; (c) few bee- and consumer-friendly methods for controlling bee mites in large apiaries are available.

394 citations


Journal ArticleDOI
01 Apr 2000-Ethology
TL;DR: There is no evidence of task partitioning among bees performing the hygienic behaviour, and the results suggest that the segregation observed could, however, be based on their response thresholds to the stimulus and/or on their ability to discriminate the various cues emanating from the dead brood.
Abstract: Hygienic behaviour performed by middle-aged worker bees is an important intranidal task in colonies of the honey bee Apis mellifera (L.). It comprises detecting diseased brood in the larval and pupal stages and removing all such infected brood, thereby decreasing the incidence of infection. Hygienic behaviour consists of two task-components: uncapping cells and removing the cell contents. The aim of this study was to observe bees performing hygienic behaviour to determine their age at performance of the behaviour and to describe their behavioural repertoire. The bees performing hygienic behaviour were middle-aged bees, younger than foragers. In the colonies where the behaviours of individual bees were observed, all bees performing the hygienic behaviour were seen to exhibit both the components, though at different frequencies. One behavioural class performed the task of uncapping cells at higher frequencies than the task of removing cell contents, while another class performed both tasks to the same extent. While these two classes had higher frequencies of the tasks comprising the hygienic behaviour but lower frequencies of other common behaviours in their repertoire, a third class of bees included those that performed all behaviours in their repertoire at similar frequencies. There was no difference in the ages of the bees in these three behavioural classes. These results suggest that there is no evidence of task partitioning among bees performing the hygienic behaviour. The segregation observed could, however, be based on their response thresholds to the stimulus and/or on their ability to discriminate the various cues emanating from the dead brood.

130 citations


Journal ArticleDOI
TL;DR: Africanized honey bees are more tolerant of infestations with the mite Varroa jacobsoni than are honey bees of European origin, and their capacity to detect and react to brood infested with this mite could be one of the factors determining this tolerance.
Abstract: Africanized honey bees are more tolerant of infestations with the mite Varroa jacobsoni than are honey bees of European origin. The capacity of these bees to detect and react to brood infested with this mite could be one of the factors determining this tolerance. We tested colonies of Africanized bees headed by queens from swarms collected in Ribeirao Preto, Sao Paulo State. The Italian colonies had queens imported directly from the USA, or from the Brazilian Island of Fernando de Noronha, where varroa-infested Italian colonies have been maintained, untreated, since 1984. Recently sealed worker brood cells were artificially infested by opening the cell capping, inserting live adult female mites and resealing the cells. Control cells were treated in the same way, but without introducing mites. The ability of the Africanized honey bees to recognize and remove this artificially infested brood was compared with that of first generation Italian/Africanized hybrid bees, and with the two groups of "pure" Italian bees, in three separate experiments. Africanized colonies removed a mean of 51% of the infested brood, while Italian/Africanized hybrid colonies removed 25%. Africanized colonies also removed a significantly greater proportion of infested brood than did Italian colonies, headed by queens from the USA (59 vs. 31%, respectively). Similarly, when Africanized colonies were compared with colonies of Italian bees from Fernando de Noronha, the former were found to be significantly more efficient at removing infested brood (61 vs. 35%, respectively), even though the population of Italian bees on this island has been exposed to and survived varroa infestations (without treatment) for more than 12 years. Only the Africanized honey bees removed a significant proportion of varroa-infested brood, when the data was corrected for brood removal from control cells.

60 citations


Journal ArticleDOI
TL;DR: The results indicate that these two parasites can have a biological interaction at the level of individual bees that is detrimental to their host colonies.
Abstract: The onset of foraging, proportion of pollen collectors, and weight of pollen loads were compared in individual honey bees (Apis mellifera) infested by zero, one (Acarapis woodi, the honey bee tracheal mite, or Varroa jacobsoni,varroa), or both species of parasitic mites. Phoretic varroa host choice also was compared between bees with and without tracheal mites, and tracheal mite infestation of hosts was compared between bees parasitized or not by varroa during development. The proportion of pollen collectors was not significantly different between treatments, but bees parasitized by both mites had significantly smaller pollen loads than uninfested bees. Mean onset of foraging was earliest for bees parasitized by varroa during development, 15.9 days. Bees with tracheal mites began foraging latest, at 20.5 days, and foraging ages were intermediate in bees with no mites and both, 17.6 and 18.0 days respectively. Phoretic varroa were found equally on bees with and without tracheal mite infestations, but bees parasitized by varroa during development were almost twice as likely to have tracheal mite infestations as bees with no varroa parasitism, 63.9 % and 35.5 %, respectively. These results indicate that these two parasites can have a biological interaction at the level of individual bees that is detrimental to their host colonies.

35 citations




Journal ArticleDOI
TL;DR: Results showed that reproduction of mites is suppressed by adding a queen selected for SMRD, and that a mite population recovers its reproduction when a SMRD queen is replaced by an unselected queen.
Abstract: This study examines changes in reproduction and mortality of Varroa destructorwhen queens from stocks of honey bees (Apis mellifera L.) that differ in susceptibility to the mites were exchanged between colonies. Queens were selected for suppression of mite reproduction (SMRD). In two experiments uniform colonies of bees were established; half the colonies were given queens selected for SMRD, and half were given unselected queens. Queens were exchanged after 7 (exper- iment 1) and 13 weeks (experiment 2). The percentage of mites that had no progeny was determined for each colony at 5 times (2 before and 3 after exchanging queens). Mites that had no progeny included live and dead mites. Results showed (1) that reproduction of mites is suppressed by adding a queen selected for SMRD, and (2) that a mite population recovers its reproduction when a SMRD queen is replaced by an unselected queen. Selection of the SMRD trait can be reduced to counting only live mites that laid no eggs and dead mites. Apis mellifera / Varroa destructor / resistance to pests / suppression of mite reproduction (SMRD)

25 citations


Book
05 Sep 2000

24 citations





Journal ArticleDOI
TL;DR: Reciprocal crosses between resistant and susceptible queens and drones proved equally effective inimproving resistance and allowing resistant stock queens tomate naturally with unselected drones, or nonresistant queens to mate with drones produced by pure or outcrossed resistant queens, can beused for improving resistance of production queens.
Abstract: The tendency of honey bees, Apis mellifera L, to become infested with tracheal mites, Acarapis woodi (Rennie), was measured in six different types of F1 colonies. The colonies were produced by mating a stock (Buckfast) known to resist mite infestation to each of five commercially available stocks and to a stock known to be susceptible to mites. Young uninfested bees from progeny and parent colonies were simultaneously exposed to mites in infested colonies, then retrieved and dissected to determine resultant mite infestations. Reduced infestations similar to but numerically greater than those of the resistant parent bees occurred in each of the six crosses made with resistant bees regardless of the relative susceptibility of the other parental stock. Reciprocal crosses between resistant and susceptible queens and drones proved equally effective in improving resistance. Therefore, allowing resistant stock queens to mate naturally with unselected drones, or nonresistant queens to mate with drones produced by pure or outcrossed resistant queens, can be used for improving resistance of production queens.


Journal Article
TL;DR: There were significant differences among treatments in terms of the development of colony population, brood rearing activity and honey yield, and Treatments had no significant effect on wax building activity and swarming tendency.
Abstract: The study was conducted at Alata Horticultural Research institute between 1994 and 1996. The aim of the study was to obtain a strong colony by way of supersedure and empty frames, feeding with saccharose syrup and encouraging egg laying of queen bees at the end of summer. According to the results, there were significant differences among treatments in terms of the development of colony population, brood rearing activity and honey yield. Treatments had no significant effect on wax building activity and swarming tendency.




Journal Article
TL;DR: The aims of the present study were to quantify the rate of HBTM infestation and damage to a local Italian strain and to the Buckfast strain, and to demonstrate the resistance of Buckfast bees to A. woodi under Mediterranean conditions.
Abstract: Infestations by honey bee tracheal mite, Acarapis woodi (Rennie) (HBTM), were followed in three groups for one year. The groups consisted of 1) acaricide (amitraz) treated Italian bee colonies, 2) untreated Italian bee colonies, and 3) untreated Buckfast colonies. Mite prevalence of Buckfast bees declined from 45% in December to 10% in April and remained low, and most queens persisted for the entire period. Furthermore, bee populations increased and honey yield was high in comparison to seasonal averages. HBTM prevalence in the treated Italian colonies remained low until July, with a large increase in bee populations and honey yield, similar to that of the Buckfast colonies; however only a quarter of the queens survived. The untreated colonies were severely infested by the mite and much reduced in population, produced little honey and most of their queens were replaced. Nosema infections and Varroa mite prevalence rates were similar in all treatments. Along with a documentation of HBTM damage and control, this is also the first demonstration of the resistance of Buckfast bees to A. woodi under Mediterranean conditions. INTRODUCTION T he honey bee tracheal mite, Acarapis woodi (Rennie) (HBTM) was recently found in Israel (Gerson et al, 1994). Our preliminary observations indicated that the mite causes considerable damage, as it does in North America (Eischen et al., 1989), but in contrast to results obtained in Europe (Bailey and Lee, 1959). Numbers of honey bee colonies decreased because of increased bee mortality, especially in winter and spring, and honey production was much reduced. An intensive control project initiated at that time showed that fumigation with the pesticide amitraz 'Beekeeping Division, Extension Service, Ministry of Agriculture, FOB 7054, Tel Aviv, Israel. 2Zerifin Breeding Apiary, ARS, The Volcani Center, FOB 6, Bet Dagan 50250, Israel. !Kimron Veterinary Institute, Bet Dagan 50250, Israel. 'Department of Entomology, Faculty of Agricultural , Food and Environmental Quality Sciences, Hebrew University, Rehovot 76100, Israel. could control the pest (Dag et al., 1997). Honey bees show a wide range of susceptibilities to HBTM infestations, and vulnerable as well as resistant strains can be selected under controlled breeding conditions (Page and Gary, 1990). 'Buckfast' strain of honey bees has been undergoing selection since 1917 in England, and is credited with possessing a comparatively elevated level of resistance to HBTM without affecting bee productivity (Brother Adam, 1987; Lin et al, 1996). The aims of the present study were to quantify the rate of HBTM infestation and damage to a local Italian strain and to the Buckfast strain. MATERIALS AND METHODS An apiary containing 30 colonies, all heavily infested with HBTM, was established near Bet Dagan (coastal plain) in December 1996. The colonies were divided into three treatment groups of equal adult populations (5.5 populated frames). Colonies were provided either with Italian queens ('Zrifin, Central Breeding Apiary', n=20) or with Buckfast queens ['Paz Breeding Apiary', originating from a Buckfast breeding apiary in Luxembourg (stock B182), n=10]. Ten of the Italian colonies were fumigated three times with amitraz (for methodology, see Dag et al., 1997) in early December, before introducing the queens, whereas all other colonies were left untreated. All queens were mated naturally in an isolated area with drones from same-strain colonies. All queens were marked by clipping one of their wings and with painting their dorsal thoraces. Samples of ca 200 bees were collected from the outer populated combs of these colonies at monthly intervals; two samples were taken during the spring months (March-April). Collected bees were kept at -18°C until examined. The thoraces of 35 bees in each subset were dissected, their thoracic disks cleared in 2M NaOH (Shimanuki and Knox, 1991) and examined for tracheal mites. Results were calculated as rates of infested bees per colony on each sampling date. Adult bee populations were collected monthly and colonies were carefully examined for brood disease. Honey yield was recorded during the spring and summer harvests. The colonies were examined for the presence of the original queens in December 1997, a year after the trial was started. In order to reduce the effects of other common bee pests, all colonies were





Book
05 Sep 2000






Patent
23 Feb 2000
TL;DR: In this article, the authors proposed a method for reinforcing the bee's natural defences against parasitic diseases, in particular against attacks from varroa mites and other acarine mites living at its expense.
Abstract: The present invention concerns bees and beekeeping, aiming at reinforcing the bee's natural defences against parasitic diseases, in particular against attacks from varroa mites and other acarine mites living at its expense. It enables to compensate the deficiencies occurring during the bee's growth period. For that purpose, elements essential for the bee are restored, for example essential minerals to the surroundings of the hive, where the bees forage flowers for nectar, by enriching or restoring the surrounding grounds with fresh water diatoms.