Plant Biol (Stuttg) 2004; 6(4): 491-497
DOI: 10.1055/s-2004-817910
Original Paper

Georg Thieme Verlag Stuttgart KG · New York

Phenology, Sex Ratio, and Spatial Distribution Among Dioecious Species of Trichilia (Meliaceae)

L. P. C. Morellato1
  • 1Departamento de Botânica, Plant Phenology and Seed Dispersal Group, Universidade Estadual Paulista, Rio Claro, SP, Brazil
Further Information

Publication History

Publication Date:
12 July 2004 (online)

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Abstract

The flowering, sex ratio, and spatial distribution of four dioecious species of Trichilia (Meliaceae) were studied in a semi-deciduous forest in southeastern Brazil. All reproductive trees (T. clausseni, T. pallida and T. catigua) with dbh ≥ 5 cm within a 1-ha plot were collected, sexed, mapped and, for individuals of each species, the distances to the nearest neighbour of the same and opposite sex were measured. For the shrub species T. elegans (dbh < 5 cm), all reproductive individuals were sampled randomly in 10 samples of 10 × 10 m. The reproductive phenology was observed at weekly to monthly intervals from May 1988 to January 1990. The species are strictly dioecious, did not present any sex-mixed trees or sex switching during the study, and sex ratio did not differ significantly from 1 : 1. The size distributions and the relative size variation were not significantly different between sexes. There was no significant segregation or clumping between individuals of either sex and no fruit production without pollination. Onset of flowering and flowering peak were synchronous between male and female plants for all species studied. Flower synchrony was related to outcrossing and pollinator attraction rather than climatic factors.

References

L. P. C. Morellato

Departamento de Botânica
Plant Phenology and Seed Dispersal Group
Universidade Estadual Paulista

C.P. 199

13506-900 Rio Claro, SP

Brazil

Email: pmorella@rc.unesp.br

Section Editor: G. Gottsberger