Biologia reprodutiva de Campylocentrum micranthum (Orchidaceae, Angraecinae)

Abstract

Campylocentrum micranthum is widely distributed throughout Brazil. The reproductive biology of C. micranthum was studied in the municipality of Sao Simao, state of Sao Paulo, Brazil. The vegetation of the region is characterized by semi-deciduous forests, swamp forests and cerrado. In the study area, C. micranthum blooms in summer. The study population consists of more than 35 individuals distributed in a swamp forest area. The plants are epiphytes and the flowers are resupinate and creamy in colour. Each flower has a tubular nectary at the base of the labellum that produces 0.053 ÊL of nectar on average. The activity of the pollinator on flowers occurs from 07:30 to 13:00. The pollinators of C. Micrantum are bees of the genera Lophopedia and Ceratina. Campylocentrum micranthum is self-compatible, but dependent on a biotic pollinator for pollen transference. In the treatment of cross-pollination, fruit set was 3.17%, while in the experiment of manual self-pollination 16% fructification was recorded. Under natural conditions (open pollination) fruit set was 36.4%.