Olfactory Discrimination by Honeybees of Terpenes Identified from Volatiles of Alfalfa Flowers

Summary

Honeybees conditioned to respond to the scent of flowers of alfalfa clone 2490 and of sainfoin responded positively to the scents of ocimene, myrcene and limonene, but not to linaloöl; bees conditioned to the scent of flowers of alfalfa clone 2B did not respond significantly to the scent of any of these substances, however.

Bees conditioned to the scent of ocimene, myrcene, or limonene responded positively to the flower scents of 6 of the 8 alfalfa (Medicago sativa) clones tested. Bees conditioned with linaloöl responded negatively to alfalfa flower scents. The first three of these terpenes appeared to be indistinguishable to the bees, but linaloöl was distinguished from the other three. The authors conclude that certain clones will be reproductively isolated by the assortive pollination of honeybees responding to differences in flower scents.