The effect of different levels of Rosa canina hydroalcoholic extract on the development of hypopharyngeal glands, growth parameters and honey production of honey bee colonies (Apis mellifera)

Abstract

Introduction: Today, for the preservation and survival of honey bee colonies, special
attention has been paid to the nutrition of colonies with extracts of medicinal plants. In this
experiment, the effect of different levels of Rosa canina hydroalcoholic extract on
population, queen egg laying, brood rearing, honey production and development of the
hypopharyngeal glands of honey bee colonies (Apis mellifera) were studied during summer
in an apiary in Ardabil province.
Materials & Methods: At the beginning of the experiment, the colonies were homogenized
according to the population, food storage and queens with same age. The colonies were fed
with control treatment and different concentrations of Rosa canina extract (2, 4 and 8% of
the extract) during 1 month. Brood rearing and queen egg laying were measured using a grid
with 5 cm × 5 cm squares that covered the entire side of a comb. 30 days after feeding the
colonies, the population of adult honey bee was measured by frame. To investigate the
development of the hypopharyngeal glands, length and width of 10 acini from different parts
of the gland were measured with 3, 6, 9, 12 and 15 days using a stereomicroscope and in T
Capture software. This experiment was performed in a completely randomized design with
four replications and four treatments.
Results: The results showed that treatment with 2% Rosa canina extract had a significant
effect on brood rearing. The effect of this treatment on queen egg laying, population and
honey production was not statistically significant. In addition, the study of growth of
hypopharyngeal glands showed that the highest growth of acini size was achieved at the age
of 3 days for honey bees fed with 4% Rosa canina extract and at 9 and 12 days of age for the
colonies fed with 2% Rosa canina extract (P<0.05).
Conclusion: In general, it can be concluded that the use of 2% of Rosa canina hydroalcoholic
extract was effective in improving the performance of honey bee colonies. Therefore, it is
recommended to beekeepers to use Rosa canina hydroalcoholic extract as a nutritional
supplement.