Reproductive phenology and mating potential in a low density tree population of Couratari multiflora (Lecythidaceae) in central Amazonia

Abstract

The reproductive phenology of a population of 39 adult trees of Couratari multiflora was studied in 'terra firme' forests located 90 kmN of Manaus, Amazonas, Brazil. Trees of this species, found in low densities, were inventoried in a 400-ha plot in which only one tree ≥20 cm DBH per 10 ha was encountered. This species flowers from January to June, with a peak in the mid-wet season (March), and fruits during the dry season (May-September). Median distances between synchronized flowering trees were 600 to 1000 m depending on the time of the flowering season. The number of synchronous flowering trees at each observation date in the 400-ha plot was 14 or 17.5 per 1 d, 13 (both) per 15 d, and three or 13 per 30 d, depending upon which of the two methods was used to evaluate synchrony. Fifty percent of the flowering trees overlapped in flowering with six to seven other flowering trees growing within a radius of 1000 m during most of the annual flowering period. Outcrossing rates were 100 % and the relatively long distances between trees in flower at the same time, support the assumption that this species is pollinated by pollinators travelling distances as far as 1000 m.