Honeybees,varroa Destructor

Кровожадный Клещ Варроа Под Микроскопом: Varroa destructor (in RUSSIAN LANGUAGE).
VIDEO LINK = http://youtu.be/rV8zWek3lTU 
Энтомолог кандидат биологических наук Фурсов Виктор рассказывает о жизненном цикле, особенностях биологии и строении клеща варроа - Varroa destructor - наружного паразита медоносных пчел - Apis cerana и Apis mellifera, питающегося гемолимфой пчел, на личинках, куколках и имаго медоносных пчел, - вызывающего опасное заболевание пчел - варроатоз. Клещи вызывают ослабление и гибель пчелиного расплода, ослабление выводящихся имаго пчел и их гибель, и переносят смертельно опасные 18 типов вирусов медоносных пчел.
Клещ варроа - Varroa destructor - имеет всесветное распространение, за исключением Австралии (в настоящее время).
Entomologist, PhD, Dr Victor Fursov is talking about mite varroa destructor - external parasite of Apis cerana and Apis mellifera, and being the source of deadly dangerous disease of honeybees - varroosis.(LECTURE in RUSSIAN LANGUAGE)

The ectoparasitic mite Varroa destructoris Anderson and Trueman is considered a destructive pest of honey bee Apis
mellifera. Potentiality of using the entomopathogenic fungi Beauveria bassiana (Balsamo) as mycoacaricide against
V. destructor was evaluated. Considerable effect of B. bassiana on Varroa mite numbers was recorded in treated colonies
compared to the control. There were significant differences in mean numbers of mite mortality rates between treated and
untreated colonies. Results indicated that conidial concentration of 5x106 spores/g caused higher mortality rate compared
to the other tested concentrations. Results showed that B. bassiana had a good potential on V. destructor when was dusted
more than one time (0, 6 and 10day). Scanning electronic microscopy examination of infected mite showed abundant
hyphal growth and sporulation on treated mite cuticle. The results indicated that dusting of colonies with fungal
conidiospores caused a reduction in the mite population reached 47.68, 33.44, 70.00 and 46.38%, 13 days after
applications at concentrations of 1 ×106
conidia/g, 2.5×106 conidia/g, 5 ×106
conidia/g, and 7.5×106
conidia/g, respectively.
The results showed also that the impact of fungus on workers bees was very low. Obtained results can suggest using
B. bassiana as a potential effective bioacaricide against V. destructor in honey bee colonies.

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.

Under Microscope: Varroa destructor under X400 Parasite of Honeybees (ENGLISH STORY) (in ENGLISH).
VIDEO LINK = http://youtu.be/pHEiH3Cpi4o 
Entomologist, PhD, Dr Victor Fursov is talking about mite Varroa destructor - external parasite of honeybees, Apis cerana and Apis mellifera, and being the source of deadly dangerous disease of honeybees - varroosis. (STORY in ENGLISH LANGUAGE). Энтомолог кандидат биологических наук Фурсов Виктор рассказывает о жизненном цикле, особенностях биологии и строении клеща варроа - Varroa destructor - наружного паразита медоносных пчел - Apis cerana и Apis mellifera, питающегося гемолимфой пчел, на личинках, куколках и имаго медоносных пчел, - вызывающего опасное заболевание пчел - варроатоз. Клещи вызывают ослабление и гибель пчелиного расплода, ослабление выводящихся имаго пчел и их гибель, и переносят смертельно опасные 18 типов вирусов медоносных пчел.
Клещ варроа - Varroa destructor - имеет всесветное распространение, за исключением Австралии (в настоящее время).

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.

The Varroa mite, Varroa destructor Anderson & Trueman (Arachnida: Acari: Varroidae), is a severe external parasitic mite of honeybees that causes great losses of colonies globally. Four concentrations (1, 2%, 5, and 10%) of Jatropha curcas oil were tested for controlling the Varroa mite. Significant effects of reducing percentage of the mite infestation (P = 0.05) after second treatment for sealed brood and after third treatment for adult workers in all tested concentrations of J. curcas were recorded. The low concentrations 1 and 2% of J. curcas were more effective than the higher ones 5 and 10% on reduction of percentage of Varroa mite infestation. Moreover, the colonies treated with the lowest concentrations of jatropha oil had the highest amount of brood area (75.75 and 77.50 inch 2) and the highest number of combs covered with bees compared with the colonies treated with the concentrations 5 and 10%. Treated colonies with the concentrations 1, 10, and 5% had a high amount of stored honey and pollen grains, 126.50, 111, and 96 inch 2 and 11.25, 9.75, and 9.75 inch 2 , respectively. Obtained results encourage researchers to study deeply the ability of using jatropha oil in the widely field of Apicultural.

Varroa destructor is a major pest in modern beekeeping operations. Most notably in the
northern hemisphere where honeybee colonies would collapse in a matter of 2-3 years if
they are not treated against this parasite. Control treatments mainly involve the use of
synthetic pesticides which can have some unwanted effects on mites such as increasing
resistance to previously effective treatments and contamination of valuable bee products.
Currently there is a tendency towards using a wider variety of treatments such as
biotechnical methods that do not cause parasite resistance, nor do they pollute the
environment. In this study we tested the efficacy of a new biotechnical trap comb method
that was developed to trap and eliminate mites in an artificial cage with a small brood
comb area, where a queen can be placed for a determinate number of rearing cycles. We
inserted this device into 16 hives in the Summer of 2020 during the honey flow season
and determined the number of mites caught in 3 brood rearing cycles. After this period,
we applied a critical chemical treatment to find out the number of varroa mites escaping
and surviving the biotechnical method to evaluate the efficacy of the cage. In our findings
we encountered some difficulties regarding individual colony behavior while
implementing the treatment, such as in brood rearing in the comb trap and colony
tendency to supersede in some hives. Despite these challenges the comb trap was
successful in trapping mites, although efficacy of treatment ranged between 1,5-92,5%,
the median value was 62% of efficacy. Most notably the 4 most infested colonies had a
66-90 % efficacy of treatment. Despite the cages not being as effective as some current
chemical acaracides, we observed an important reduction in mite population growth in all
hives during the time of treatment. These results could possibly favor the winter survival
of highly infested colonies, but varroa population dynamics and infestation need to be
considered individually. We conclude that because of unpredictable individual colony
behavior, this method if used by itself, may not eliminate mite populations in all hives in
an apiary, and mite transportation by drift to other successfully treated hives where
treatment was effective is still a major risk. Therefore, we recommend this biotechnical
method must be used within an IPM scheme to effectively control varroa in the apiary.

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%)