| Abstract Detail
Tropical Biology Section Araya, Ana L. [1], Rocha, Oscar J. [1]. Reproductive and vegetative phenology for two populations of Miconia calvescens DC. (Melastomataceae) in Costa Rica: an invasive plant in the Hawaiian and French Polynesia Islands. The reproductive and vegetative phenology of 47 trees of Miconia calvescens DC. (Melastomataceae) was studied in two populations in Costa Rica from Dec-2001 through Dec-2003. We monitored four phenological stages (budding, flowering, fruiting, and leafing) every three weeks using a semi-quantitative scale. Both years, flower buds and panicles were produced from mid-August to mid-November and flower anthesis occurred from mid-November to mid-December. In 2003, more frequent observations were conducted during the flowering period. We found that flowering (anthesis) occurs in short episodes that last less than a week, that are separated by two weeks or more. Flowering synchronization occurred both at the population and individual level, percentage number of trees per population involved in the flowering peaks ranged from 53 to 82%, and flowering intensities among blooming trees was higher than 50% of the crown. Anthesis coincides with the end of the rainy season and also with a decrease in day length. Observations of a longer period between flowering episodes in one population suggest that rain may delay anthesis. Fruits started developing almost immediately after flowering and fruits maturated gradually from mid-March through late-April. All trees produced fruits during the 2002 season and all but one during the 2003 season. Vegetative growth starts as fruits mature and is most intense right before the initiation of new flower buds. The observed phenological pattern coincide with what has been described for other species of the same genus. These findings suggest that pollination and seed dispersal mechanisms have a strong effect on the patterns of flower anthesis and fruit maturation. Differences in the phenological patterns between plants of M. calvescens in their native range and those of invasive populations in Tahiti are discussed. Log in to add this item to your schedule
1 - Kent State University, Department of Biological Sciences, Po Box 5190, Kent, Ohio, 44242-0001, USA
Keywords: flowering phenology reproductive biology Miconia pollination Seed dispersal Invasive Species.
Presentation Type: Oral Paper Session: 8-2 Location: 410/Hilton Date: Monday, August 15th, 2005 Time: 10:30 AM Abstract ID:350 |