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NEW ZEALAND BEEKEEPER, MAY 2017
they have already observed which species are flowering within foraging range. To support Pollen Profile analyses, the GNS Pollen Lab has a wide-ranging reference collection with pollen images for many plant species used by bees. The collection includes photos of pollen in both the acetolysed and non-acetolysed (simply stained only) formats. The images are produced using a high- powered compound microscope specifically designed for publication level photography (Figure 4). Some good examples of this type of work can be seen in the poster describing the recent research by Xun Li showing that mānuka and kānuka pollen are different and can be distinguished based on several characters (Li et al, 2015). This research was based on samples covering most of the geographic and taxonomic range of species and types of mānuka and kānuka in New Zealand in collaboration with Dr Peter de Lange. New resources for beekeepers being produced To help create and interpret Pollen Profiles for pollen pellets and honey collected by bees, the Trees for Bees team is producing several new resources for online and workshop delivery. Our goal is to make the methods available for do-it-yourself analyses by beekeepers. The two main resources under development are an illustrated online GNS Pollen Atlas for bee plants in New Zealand and an illustrated Trees for Bees Flower catalogue. The illustrations and information will help beekeepers verify their evidence about which pollen and nectar sources their bees are foraging on in their apiary sites.
Figure 3. Xun Li, GNS Pollen Lab, processing pollen by the acetolysis method which requires a chemical fume hood that handles the acid fumes.
pollen that has either landed in a different flower’s nectar before the bee collected it, or has been blown directly into the hive or fallen off bees while grooming. On the other hand, pollen in the bee pellets from a wind- pollinated species indicates the bees are foraging on that species for pollen, a result that seems to be a contradiction to some people because they assume wind-pollinated plants are not visited by bees. It is important to support the interpretation by observations on the way the bees fit into the flower to see how easily the pollen can be dislodged into the nectar, as demonstrated in our analysis of the mānuka flower (Newstrom-Lloyd, 2017). When constructing Pollen Profiles for a new apiary site, it is often a good idea to use acetolysis methods to prepare pollen for identification (see Figure 3). Acetolysis is the process of clearing the pollen grains so that the skeletal features show up more obviously for pollen identification (Figure 5). This process requires a fume hood in a lab and is most useful when identifying unknown pollen. However, the acetolysis process is not needed when the pollen is already familiar from previous work at the apiary site or beekeepers’ expert knowledge. In these instances, a simple staining method can often suffice (Figure 6). Beekeepers can learn to recognise pollen and pollen pellets at the local level for their apiaries, particularly if
(Newstrom-Lloyd, 2016 August, 2016 September). The Naati Beez team sampled pollen and honey every two weeks from spring through autumn. The pollen and honey samples from the pollen hive traps (over a 24-hour period) and frame honey (when present) were sent for processing and identification by Dr Ian Raine and Dr Xun Li, experienced honey palynologists at the GNS Pollen Lab. From the pollen content data, Ian produced Pollen Profiles. An illustration of the profiles is given for the bee pollen pellets (Figure 1), and also for the honey samples (Figure 2) taken from the November 27th period at the East Cape site. In our new MPI Sustainable Farming Fund Grant 2016 to 2019, we are collaborating with Ian and Xun again to improve our protocols for the Pollen Profile methods by testing them at several more sites in the North Island. The initial interpretation of a Pollen Profile requires an understanding of pollen characteristics as well as floral morphology. For example, we know which plant species have pollen that is under-represented versus over-represented in honey, and why (see Bryant, 2001; Moar, 1985; Sawyer, 1988). We also know which plants have abundant nectar versus those with minimal nectar or no nectar. For example, pollen from a no-nectar plant in the honey indicates a wind-blown
Figure 4. Ian Raine, GNS Pollen Lab, using a compound microscope designed to show pollen grains on the computer screen and in the microscope as well as take high resolution photographs.
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