Floral biology and reproductive system of Annona squamosa L. (Annonaceae) in Petrolina-PE, Brazil

摘要

Aspects of pollination biology and reproductive system of Annona squamosa L. were studied in Petrolina-PE, Northeastern Brazil, from June 1999 to February 2000, from 6:00 a.m. to 6:00 p.m. The flowers of A. squamosa are hermaphrodite, axillary, with fleshy calyx and corolla forming a floral camera which serves as a shelter, food source and mating place for visitors. The flowers also show light color petals, produce strong and bad odors. The anthesis takes place around 5:00 p.m., the flowers last for approximately two days, and show female phase in the first twenty hours and male phase in the following twenty hours, characterizing dichogamy. Carpophilus hemipterus, Carpophilus sp and Haptoncus ochraceus (Nitidulidae) are the main flower visitors and according to frequency, time and behavior, are considered pollinators of this species. The species is self-compatible, however the germination tests indicated that seeds from cross-pollination show higher viability than seeds from geitonogamy.