The 43rd International Apicultural Congress Apimondia took place in the Ukrainian capital, the city of Kiev on September 29th – October 04th 2013, in which we were participants and presented our work. On November 04th – 9th 2014 we also... more
The 43rd International Apicultural Congress Apimondia took place in the Ukrainian capital, the city of Kiev on September 29th – October 04th 2013, in which we were participants and presented our work. On November 04th – 9th 2014 we also participated in the 10th Apislavia Congress which was arranged concurrently with the 4th International Mugla Beekeeping & Pine Honey Congress in Oludeniz, Mugla Province, in Turkey.
Recent declines in honey bee populations and increasing demand for insect-pollinated crops raise concerns about pollinator shortages. Pesticide exposure and pathogens may interact to have strong negative effects on managed honey bee... more
Recent declines in honey bee populations and increasing demand for insect-pollinated crops raise concerns about pollinator shortages. Pesticide exposure and pathogens may interact to have strong negative effects on managed honey bee colonies. Such findings are of great concern given the large numbers and high levels of pesticides found in honey bee colonies. Thus it is crucial to determine how field-relevant combinations and loads of pesticides affect bee health. We collected pollen from bee hives in seven major crops to determine 1) what types of pesticides bees are exposed to when rented for pollination of various crops and 2) how field-relevant pesticide blends affect bees’ susceptibility to the gut parasite Nosema ceranae. Our samples represent pollen collected by foragers for use by the colony, and do not necessarily indicate foragers’ roles as pollinators. In blueberry, cranberry, cucumber, pumpkin and watermelon bees collected pollen almost exclusively from weeds and wildflowers during our sampling. Thus more attention must be paid to how honey bees are exposed to pesticides outside of the field in which they are placed. We detected 35 different pesticides in the sampled pollen, and found high fungicide loads. The insecticides esfenvalerate and phosmet were at a concentration higher than their median lethal dose in at least one pollen sample. While fungicides are typically seen as fairly safe for honey bees, we found an increased probability of Nosema infection in bees that consumed pollen with a higher fungicide load. Our results highlight a need for research on sub-lethal effects of fungicides and other chemicals that bees placed in an agricultural setting are exposed to.
A large-scale field survey was conducted to screen major Saudi Arabian beekeeping locations for infection by Melissococcus plutonius. M. plutonius is one of the major bacterial pathogens of honeybee broods and is the causative agent of... more
A large-scale field survey was conducted to screen major Saudi Arabian beekeeping locations for infection by Melissococcus plutonius. M. plutonius is one of the major bacterial pathogens of honeybee broods and is the causative agent of European Foulbrood disease (EFB). Larvae from samples suspected of infection were collected from different apiaries and homogenized in phosphate buffered saline (PBS). Bacteria were isolated on MYPGP agar medium. Two bacterial isolates, ksuMP7 and ksuMP9 (16S rRNA GenBank accession numbers, KX417565 and KX417566, respectively), were subjected to molecular identification using M. plutonius-specific primers, a BLAST sequence analysis revealed that the two isolates were M. plutonius with more than 98% sequence identity. The molecular detection of M. plutonius from honeybee is the first recorded incidence of this pathogen in Saudi Arabia. This study emphasizes the need for official authorities to take immediate steps toward treating and limiting the spread of this disease throughout the country.
This study evaluated the level of invasion of Varroa mite into worker brood cells, the infestation rate on adult worker honeybees, total and effective reproduction rates of the mite in Africanized honeybee colonies under royal jelly or... more
This study evaluated the level of invasion of Varroa mite into worker brood cells, the infestation rate on adult worker honeybees, total and effective reproduction rates of the mite in Africanized honeybee colonies under royal jelly or honey production. Invasion and infestation rates were not statistically different between honeybee colonies producing honey or royal jelly and the averages for these parameters were 5.79 and 8.54%, respectively. Colonies producing honey presented a higher (p < 0.05) total and effective reproduction of Varroa than colonies producing royal jelly. There was a negative correlation between levels of invasion and infestation with minimum external temperature, relative humidity and rainfall. The variables month and season influenced the development of the mite, but rates were low and within the range normally found in Brazil for Africanized honeybee colonies, which confirm the greater resistance of these honeybees to Varroa destructor than European honeybees.
The effects of oxalic acid administered by the trickling method on brood development of honey bee colonies were evaluated (a) by observing the development of marked cells of young (< 3 days old) and old (> 3 days old) larvae, and (b) by... more
The effects of oxalic acid administered by the trickling method on brood development of honey bee colonies were evaluated (a) by observing the development of marked cells of young (< 3 days old) and old (> 3 days old) larvae, and (b) by measuring the area of open brood for several weeks post application. Oxalic acid, dissolved in a 50% sugar solution, with an end concentration of 3% w/v oxalic acid, was applied twice by the trickling method during summer to 10 colonies. A high percentage of young (12.6% and 9.5%) and old honey bee larvae (10.6% and 5.6%) were removed from their cells after the first and second oxalic acid applications, respectively. The surface of the open brood area was also reduced by 17.5% after the two oxalic acid applications and stayed low for about two months. For the same period of time the open brood area in 10 control colonies increased by 34.5%. The two oxalic acid applications removed 60 ± 12% of varroa mites adhering to adult honey bees, while the natural fall of mites measured in control colonies (for a period of 40 days) was 32 ± 4%. Combining the detrimental effect on brood development with the low relative effectiveness on varroa removal, oxalic acid application by the trickling method when open brood is present is not as safe as has been regarded in the past. Consideration needs to be given to the use of different sugar and oxalic acid concentrations in the treatment solution in order to minimize its adverse effects on open honey bee brood
Paenibacillus larvae is one of the major bacterial pathogens of honey bee broods and the causative agent of American foulbrood disease. The factors responsible for the pathogenesis of American foulbrood disease are still not fully... more
Paenibacillus larvae is one of the major bacterial pathogens of honey bee broods and the causative agent of American foulbrood disease. The factors responsible for the pathogenesis of American foulbrood disease are still not fully understood, and the increasing resistance of P. larvae to commonly used antibiotics necessitates a search for new agents to control this disease. The in vitro antibacterial activities of 28 plant essential oils against P. larvae ATCC 9545 were evaluated. Out of the 28 plant essential oils tested, 20 were found to be effective in killing P. larvae. Based on their minimum bactericidal concentration (MBC) values, the effective oils were grouped into three categories: highly effective, moderately effective and minimally effective. Jamaica pepper oil, mountain pepper oil, ajwain oil, corn mint oil, spearmint oil, star anise oil, nutmeg oil and camphor oil were highly effective, with MBC values between 162.0 and 375.0 mg/mL. Jamaica pepper oil was the most effective essential oil, with an MBC value of 162.0 mg/mL. The results of the time-response effect assays showed that no viable P. larvae cells were observed after 24 h of treatment with Jamaica pepper oil (162.0 mg/mL), 36 h of treatment with mountain pepper oil (186.0 mg/mL), 48 h of treatment with ajwain oil (224.8 mg/mL) or 48 h of treatment with oxytetracycline (5.89 mg/mL). The tested essential oils exhibited significant antimicrobial activities against P. larvae, and they may contain compounds that could play an important role in the treatment or prevention of American foulbrood disease.
A total of 72 Apis melllifera jemenitica honeybee samples were collected from eight different provinces within Saudi Arabia. Samples consisted of adult worker bees and capped brood cells. All samples were analyzed to estimate Varroa... more
A total of 72 Apis melllifera jemenitica honeybee samples were collected from eight different provinces within Saudi Arabia. Samples consisted of adult worker bees and capped brood cells. All samples were analyzed to estimate Varroa destructor mite infestation levels, and isolated V. destructor mites (n = 90) were subjected to DNA analysis. Results revealed that all colonies sampled in this survey were infested with V. destructor mites. The overall average infestation levels were 5.5 ± 4.8% and 13.1 ± 10.6% on adult worker bees and in capped brood cells, respectively. Differences in worker infestation levels were not significant among sampling locations (F = 1.5; P = 0.19); however, infestation levels in capped brood cells were highly significant among locations (F = 5.2; P < 0.001). Moreover, results indicated that all V. destructor mites from A. m. jemenitica were recognized as a Korean haplotype of V. destructor. These results should assist forthcoming mite management efforts in Saudi Arabia.
Varroa destructor is the main pest of the honey bee Apis mellifera, causing colony losses. We investigated the effect of temperature on the autumn abundance of V. destructor in bee colonies over 1991-2020 in Central Europe. We tested the... more
Varroa destructor is the main pest of the honey bee Apis mellifera, causing colony losses. We investigated the effect of temperature on the autumn abundance of V. destructor in bee colonies over 1991-2020 in Central Europe. We tested the hypothesis that temperature can affect autumn mite populations with different time-lags modulating the bee abundance and brood availability. We showed that raised spring (March-May) and autumn (October) temperatures reinforce autumn V. destructor infestation in the bee colonies. The critical temperature signals embrace periods of bee activity, i.e., just after the first cleansing flights and just before the last observed bee flights, but no direct effects of phenological changes on V. destructor abundance were found. These effects were potentially associated with increased bee reproduction in the specific periods of the year and not with the extended period of activity or accelerated spring onset. We found significant effects of autumn bee abundance, autumn capped brood abundance, and the number of colonies merged on autumn mite infestation. We also observed differences in V. destructor abundance between bees derived from different subspecies. We indicated that climatic effects, through influence on the bee abundance and brood availability, are one of the main drivers regulating V. destructor abundance.
Varroa destructor is the main pest of the honey bee Apis mellifera, causing colony losses. We investigated the effect of temperature on the autumn abundance of V. destructor in bee colonies over 1991–2020 in Central Europe. We tested the... more
Varroa destructor is the main pest of the honey bee Apis mellifera, causing colony losses. We investigated the effect of temperature on the autumn abundance of V. destructor in bee colonies over 1991–2020 in Central Europe. We tested the hypothesis that temperature can affect autumn mite populations with different time-lags modulating the bee abundance and brood availability. We showed that raised spring (March–May) and autumn (October) temperatures reinforce autumn V. destructor infestation in the bee colonies. The critical temperature signals embrace periods of bee activity, i.e., just after the first cleansing flights and just before the last observed bee flights, but no direct effects of phenological changes on V. destructor abundance were found. These effects were potentially associated with increased bee reproduction in the specific periods of the year and not with the extended period of activity or accelerated spring onset. We found significant effects of autumn bee abundance...
Through a country-wide survey, the present study aimed at investigating the extent of the spread of Varroa destructor in Nigeria. To this end, a total of 122 Apis mellifera colonies from 13 localities were sampled in regions without... more
Through a country-wide survey, the present study aimed at investigating the extent of the spread of Varroa destructor in Nigeria. To this end, a total of 122 Apis mellifera colonies from 13 localities were sampled in regions without previous assessment of the mite. Infestation and prevalence rates were estimated using the soap washing method. Varroa mites were found in 87% of the sampled colonies with a parasitic load ranging from 0.20 to 16.35 mites per 100 adult bees per colony. Given the presence of the mite with a very high prevalence in all the sampled localities and the fact that each of the states from which the mite is not yet reported is next to at least one occupied state, it is very likely that V. destructor spread throughout Nigeria. Future molecular analyses can evaluate whether V. destructor in Nigeria stems from a single source or additional introductions.
This study was carried out at the apiary of Agricultural Experimental Station, Faculty of Agriculture, Cairo University during two years 2011, 2012. To study the seasonal fluctuation of nosema disease, also to diagnose the specie of... more
This study was carried out at the apiary of Agricultural Experimental Station, Faculty of Agriculture, Cairo University during two years 2011, 2012. To study the seasonal fluctuation of nosema disease, also to diagnose the specie of Nosema which more dominance in Egypt. Eight honeybee colonies were used in the first study. These colonies were nearly at the same strength in the beginning of experiment and headed by young mated queens. Samples of 15 bees were collected from the entrance of each colony at 2 weeks internals throughout the year and examined collectively for the presence of nosema spores. The obtained results showed that the nosema levels to be at their highest during April, 2011(7.17*106 spores/bee/col.) Then this parameter gradually decreased during the following months and reached to 1.28*106 spores/ bee/col. at the end of June. The infection level increased again during autumn months as a result of severe attacking of oriental hornet and prevents the bees from defecating flights. On the other hand the nosema infection reached to the lowest level during December (0.13*106spores/bee/col.) as a result of decreasing of brood rearing. Generally, the variations in colony infection level between the periods throughout the year are significantly differed. In the second spring, 2012 the cycle may be moved out of phase according to climatic conditions and colony stress. In the second experiment, samples of 50 bees were randomly collected from the entrances of ten colonies .From three different regions in Egypt. DNA Samples were obtained from the abdomen of infected bees were used in the co amplifaction of 165r RNA gene of N. apis & N. cerana and the honeybee ribosomal protein RpS5 gene the obtained results showed that the Nosema spp. which is dominance in Egypt is Nosema ceranae not Nosema apis.
The efficacy of using two different application methods (smoking and essential oils) on reduction of Varroa mite infestation level in honey bee colonies were studied at the apiary of agriculture experimental station, faculty of... more
The efficacy of using two different application methods (smoking and essential oils) on reduction of Varroa mite infestation level in honey bee colonies were studied at the apiary of agriculture experimental station, faculty of agriculture, Cairo university throughout Autumn 2011 and spring 2012. The obtained results showed that using essential oils were more effective than using botanical smokes as general conclusion, but the most effective application was using sumac seeds smokes which resulted 64.8% (mean reduction percent during Autumn 2011 and spring 2012) followed by eucalyptus oil (62.7%) , mint oil (61.7%) and finally eucalyptus leaves smoke that resulted the lowest percent of reduction (28.9%)
