Janja Filipi

Colony development of two Carniolan genotypes (Apis mellifera carnica) in relation to environment

Summary The objective of this study was to compare the colony development cycle (unsealed and sealed worker brood, drone brood, pollen and colony strength) of two Apis mellifera carnica subpopulations in two distinct environments (alpine and continental). At each test location were two sub groups of 12 colonies headed by naturally mated sister queens from either the Institute of Apiculture Lunz am See, Austria (AT) or from the Faculty of Agriculture University of Zagreb, Croatia (HR). Colony development was monitored every 14 days. The HR genotype, adapted to a continental climate, had faster spring brood development in both environments. During spring and early summer the AT genotype maintained the number of sealed brood cells at a constant level in the more favourable conditions, although the amount of unsealed brood reached its maximum in early June. The environment influenced colony development, food stores and colony strength. Interaction between genotype and environment did not affect the number of unsealed brood cells, but the difference was statistically significant for the number of sealed brood cells. The study indicated the presence of a number of genotype and environment interactions between the two honey bee genotypes and their colony traits.

Multifloral honey from Gacka region

Gacka region and northern slopes of Velebit are typical mountain meadow honey areas. Bees pasture is relatively stable, almost evenly distributed throughout the season. The aim of the research is to determine the characteristics of honey in the Gacka region based on mellisopalinological and physicochemical analyses. In order to collect honey samples from Gacka region, honey competition was organized in 2008, 2009 and 2010. A total of 69 samples of honey were collected. Water content in the studied honey samples ranged from 14.60 to 18.20% with a mean value of 16.32%. Floral honey samples from 2009 and 2010 had a higher pH values (4.97, 4.83) compared to the samples from 2008 when the value was 4.68. In the investigated samples of floral and meadow honey the share of reducing sugars ranged from 55.31% in 2008 year to 77.02% in 2010. Honey types were separated on the basis of physicochemical parameters using Canonical discriminant analysis.