Feeding pollen supplements to honey bee colonies during pollination of sweet pepper in enclosures

The use of honey bees to pollinate vegetable crops in greenhouses has increased considerably lately. One of the most important greenhouse crops that benefit from honey bee pollination is sweet pepper, Capsicum annuum. However, colonies placed inside sweet pepper greenhouses deteriorate quickly, resulting in reduced pollination activity and eventually need for replacement. We tested whether honey bee colonies kept in enclosures of sweet pepper suffer from nutritional deficiencies by following their food reserves and brood production. In both years of the study, colonies not supplemented with a protein diet deteriorated during the 68-day (1999) and 88-day (2000) duration of the study. Colonies that were given pollen supplements (500 g per week) maintained a high level of brood production. Levels of sealed brood provided the most informative measure of the efficacy of the supplementary feedings. As the winter progresses, sweet pepper flowers produce fewer pollen grains and with reduced viability, and thus greater pollinator activity is needed. We show that by feeding pollen supplements, colonies maintained in enclosures of sweet pepper over the long flowering period of the crop, can sustain stable levels of brood production, which are needed for achieving efficient pollination.