The aim of this study was to determine the factors required to pollinate 'Hort16A' (Actinidia chinensis Planch. var. chinensis) kiwifruit. Pistillate flowers (88%) opened between 0500 and 1200 h. There was no indication of nectar production or viable pollen on pistillate flowers. Stigma receptivity peaked on the second day after anthesis and then declined. Excluding honey bees (Apis mellifera L.) significantly (p B0.05) reduced fruit set and seed number. Flowers exposed to wind pollination for 5 days produced fruit with an average of 110 seeds. When equal numbers of staminate and pistillate flowers were presented on a tray, only 2.8% of visits were to staminate 'Sparkler' flowers and 2.2% to staminate 'Meteor' flowers. Single bee visits to pistillate flowers produced averages of 51Á61.7 seeds. The percentage of staminate pollen carried by honey bees significantly decreased with increasing distance from staminate vines (0.8%/m). Average seed number decreased by 0.75%/m.

White clover (Trifolium repens L.) is grown throughout New Zealand in pasture and as a seed crop in the South Island. This investigation was conducted to determine the number of honey bee visits necessary to fully pollinate white clover flowers; the number of foraging honey bees per hectare required to reach the maximum seed number per floret; and to assess the level of white clover pollination in Canterbury. The theoretical maximum number of seeds that can be produced per white clover floret is six, based on the number of ovules present. Based on the number of seeds resulting from a single bee visit (mean 01.24), it is calculated that in an 8 h foraging day, 19,420 bees would be required per hectare to reach maximum seed number per floret, assuming that no floret received more visits than required. Bee activity was assessed at two clover sites with an estimated 20,124 foraging bees per hectare. This number should have been enough to reach maximum seed number per floret. However, seed set in these fields was approximately half of its theoretical potential.

Honey bees (Apis mellifera) have been implicated in the spread of the fire blight pathogen (Erwinia amylovora), and may transmit other bacterial plant pathogens in the process of pollinating crops. Furthermore, the movement of hives from one orchard to another could spread plant diseases over large distances. We investigated whether honey bees might play a role in the transmission of different pathovars of Pseudomonas syringae. We detected live P. syringae pv. actinidiae (Psa), a pathogen of kiwifruit (Actinidia spp.), on caged bees in hives 6 days after the bees were inoculated with Psa, and recorded up to 1.8×10 4 colony forming units of Psa on honey bees foraging naturally on flowers of Psa-infected vines. P. syringae pv. syringae (PssSmr), a pathogen with a wide host range, was spread to untreated bees in a hive within 24 h following the introduction of foragers doused in PssSmr-contaminated pollen and was still detected on bees 9 days later. PssSmr was found on caged bees in hives 6 d after they were inoculated and PssSmr survived in hives for at least 14 days. These results demonstrate that P. syringae can survive in beehives and spread within a hive, which broadens the applicability of results from studies of E. amylovora and supports recommendations for a stand down period before moving beehives from a contaminated to a noncontaminated orchard.

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