In the past, honey bee used to get most of the attention regarding pollination. Today, many studies show the importance of wild pollinators. In this thesis, we wanted to determine the diversity of pollinators on four varieties of raspberry bush (Rubus idaeus) and assess the importance of wild pollinators. The field work has been done in the orchard maintained by The Agricultural Institute of Slovenia in Brdo pri Lukovici during two seasons in 2016 and 2017. Besides mapping the species and their visiting frequencies we also determined the speed of pollination. We found that the most numerous pollinator of raspberries is the honey bee. Other pollinators (solitary bees, wasps, bumblebees and dipterans) were present in much lower numbers. During the day, activity has differed greatly among these groups. Honey bee had its peak activity in the middle of the day. Only if the weather was very hot and sunny their activity decreased. Bumblebees had two peaks in activity, one in the morning and one in the late afternoon. There were also differences in the speed of pollination between different groups. Solitary bees spent the longest time harvesting each flower. In contrast, bumblebees visited the highest number of flowers in a certain time period. The speed of pollination in honey bees and wasps is between solitary bees and bumblebees. When assessing the importance of pollinators, we have to be aware that besides abundance, pollination efficiency is also very important. To ensure reliable pollination we need diverse pollinators. Their importance can be more obvious during unpredictable weather conditions.
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