Bumblebee cost-effectiveness for sunflower pollination in isolation cages

The lack of pollinators during sunflower seed production in isolation cages can lower the seed yield up to 90%. That is why we analyzed the cost-effectiveness of bumblebee usage as pollinators. Usual inbred line combinations for seed production were sown and effciency of hand pollination was compared to open pollination and bumblebee pollination. Bumblebees and honeybees were more effcient than hand pollination. Their constant presence during the whole flowering period led to better pollination conditions which reflected on increased seed yield. If pollination cost is compared per obtained kg of seed, than honeybees with 74 rsd/kg seem to be the best choice but not realistic because their colonies are too big for cages. Bumblebee colonies (694 rsd/kg) were as productive as open pollination but they were also twice as expensive in comparison to hand pollination (320 rsd/kg). Hand pollination impose as the best pollination method for sunflower under isolation cages, while in the cases when there is a lack of workers or the seed yield is of absolute importance bumblebees represent a good alternative.