Title

Seed yields in canola (Brassica napus cv. Karoo) depend on the distance of plants from honey bee apiaries

Document Type

Article

Publication Date

2005

Journal Title

Australian Journal of Experimental Agriculture

Keywords

canola, Brassica napus, seed, distance, oil, pollination, pod, honey bee, Apis mellifera.

Abstract

This research examined the benefits of placing hives of honey bees (Apis mellifera L.) in canola (Brassica napus L.) at a density of approximately 1 hive/ha. We tested three main hypotheses. First, deploying honey bees increases the yield of seed. Second, that the benefits of honey bee pollination decline the further plants are from an apiary. Third, poorly pollinated plants should channel more resources into larger seeds, whereas plants benefiting from insect pollination should produce more but smaller seeds. The experiment confirmed all three hypotheses. Yields of seed increased by more than 20% or by 400 kg/ha, whereas the yield declined in plots located more than 200 m from the apiary. There are several explanations for the increased yield, including an enhanced production of fertile pods and, therefore, more seed, partucularly small seed.