Vibratory Collection of Actinidia deliciosa (Kiwifruit) Pollen

Abstract

Dry, powdery pollen grains were expected from 'buzz pollinated' flower species. However, vibration of Actinidia deliciosa (kiwifruit) anthers (a buzz pollinated species) by a mechanical shaker, at similar vibrations to Bombus terrestris caused clumps of pollen joined by small droplets of tapetal fluid to be ejected. Pollen that was largely covered with tapetal fluid could not be removed by vibration, whereas dehydrated pollen was easily removed, even without vibration. The late desiccation of A. deliciosa anthers after anthesis meant that pollen removed by vibration depended on the anther maturity. The presence of the droplets gives insects which vibrate while foraging advantages over insects which do not. A vibration attachment on a commercial pollen harvester increased the weight of pollen collected by 57% over the whole day; 91% in the afternoon.