IDENTITY, BEHAVIOR, AND EFFICACY OF NITIDULID BEETLES (COLEOPTERA, NITIDULIDAE) POLLINATING COMMERCIAL ANNONA SPECIES IN FLORIDA

Insect pollination of commercial annonaceous crops is variable among l ocalities and poorly understood. To gain basic information for use in pollinator management programs, we studied the nitidulids that pollina te commercially grown sugar apples (Annona squamosa L.) and atemoyas ( A. squamosa X A. cherimola P. Miller) in Florida. Only flowers visited by nitidulids set fruit. We found nine species of nitidulid flower vi sitors, seven of which pollinated. Carpophilus mutilatus Erichson was the most important pollinator in terms of efficacy and abundance, foll owed by C. fumatus Boheman and Haptoncus luteolus (Erichson). The Anno na flowers, which are protogynous, are entered by the beetles usually during the female phase. Peak entry into atemoya flowers occurs in the morning (0700-0900 EST) and into sugar apple flowers both in morning (0700-1100) and evening (1700-2100). The beetles remain inside up to 2 2 b, until the flowers senesce and the stamens fall. In 1989, natural fruit set ranged from 0-29% of sampled flowers per day in atemoya grov es and from 0-10% of flowers per day in sugar apples. Percentage of fr uit set is correlated with numbers of nitidulids in the flowers.