REARING AND UTILIZATION OF THE RED MASON BEE - Osmia rufa L. (Hymenoptera, Megachilidae) FOR ORCHARD POLLINATION

Summary Mason bee (Osmia rufa) was introduced for the orchard pollination about 15-20th April in 2000-2002. Due to very high temperatures noted last years in May the flight of Osmia rufa females was short and ended about 15th June. Females founded their nests equally willingly in tubes made of reeds (o 6-8 mm), and in those of paper (o 7 mm). In the year 2000 during the blooming period tubes were sampled in 7-day intervals, three on each sampling date, for microscopic palynological analysis of cells. The nests showed the presence of 26% to 31% pollen from orchard plants (apple, cherry and blackcurrant) in full blooming period only. After this period the only orchard plant-derived pollen in the nests was that from anemophilous walnut (Juglans regia) - up to 71%. Density of Osmia rufa females required to pollinate 1 hectare of some orchard plants was calculated based on pollen output from 1 flower and pollen data from the cells.