摘要 : In an experiment conducted in an almond orchard (2 rows of Um Al Fahem alternated with rows of 54 and Ne Plus Ultra as pollenizers) in Arad Valley, Israel, during 2006, 95 honey bee colonies were introduced at the onset of floweri... 展开 In an experiment conducted in an almond orchard (2 rows of Um Al Fahem alternated with rows of 54 and Ne Plus Ultra as pollenizers) in Arad Valley, Israel, during 2006, 95 honey bee colonies were introduced at the onset of flowering at 4 colonies/ha. Forty bumble bee (Bombus terrestris) colonies were also introduced in one corner of the orchard (spread over 2 ha). Each bumble bee colony, which had approximately 100 workers, was not supplied with sugar syrup or pollen patty. Fruit set and bumble bee activity were evaluated in selected trees 0, 150 or 450 m away from a bumble bee colony (MBBC). Both parameters were significantly greater at 0 MBBC than at 150 and 450 MBBC. Fruit set increased despite the reduction in honey bee activity toward the bumble bee colony, suggesting the significant contribution of bumble bees to almond fruit set.. 收起