Passage of Pollens through Proventriculus in Honey Sacs of European Bee (Apis mellifera carnica L.)

Abstract

During the transfer of pollen grains in sugar solution through the proventriculus, a selection of pollen grains took place according to their size and shape, which altered the relative proportions of the different pollen grains. After feeding, amounts of pollen grains in honey sac were remarkedly reduced. Pollens of rape (Brassica napus L.) which are small (about 25 micron) and have smooth exine could not be completely filtrated by the filiform –hair of the proventriculus. One hundred thirty five minutes after feeding, they remained in the honey sac. Pollens of pine (Pinus sylvestris L.) which have two air-sacs (wing) floated on the upper side of honey sac. Pollens of aster (Aster sp.) and dandelion (Taraxacum officinale Web.) are relatively bigger and more spiny than rape pollens. They could be easily filtered from the fluid in honey sac by the filifrom-hairs of the comb and passed into the midgut in 95 and 100 min., respectively.