Effectiveness of pollination was predicted in a 'Conference' pear orchard by examining pollen tube growth. This histological technique allows a reliable and rapid estimation of pollination quality. Intra- and inter-cultivar compatibility was tested by hand pollinations with 'Conference' or 'Doyenne' pollen, respectively. In intra-cultivar pollinated flowers, limited pollen tube growth and large callose plugs were observed. This cultivar was thus considered self-incompatible. As insect pollinators deposit variable quantities and mixtures of intra-cultivar (incompatible) and inter-cultivar (compatible) pollen grains, their relative efficiency can differ greatly. The pollination efficiencies of honeybees (Apis mellifera L.) and of bumblebees (Bombus terrestris L.) were compared by examining pollen deposition and pollen tube growth following single floral visits. Bumblebees deposited higher quantities of more compatible pollen grains per stigma than honeybees; whereas no differences were detected in pollen tube growth. The implications for 'Conference' pear production are discussed.
Jacquemart, A.-L., Michotte-Van der Aa, A., & Raspé, O. (2006). Compatibility and pollinator efficiency tests on Pyrus communis L. cv.‘Conference’. Journal of Horticultural Science and Biotechnology, 81(5), 827-830. https://doi.org/10.1080/14620316.2006.11512145 (Original work published 2006)