Plant Ecology

, Volume 192, Issue 2, pp 169–179

Flexible mating system in a logged population of Swietenia macrophylla King (Meliaceae): implications for the management of a threatened neotropical tree species

  • Maristerra R. Lemes
  • Dario Grattapaglia
  • James Grogan
  • John Proctor
  • Rogério Gribel
Original Paper

DOI: 10.1007/s11258-007-9322-9

Cite this article as:
Lemes, M.R., Grattapaglia, D., Grogan, J. et al. Plant Ecol (2007) 192: 169. doi:10.1007/s11258-007-9322-9

Abstract

Microsatellites were used to evaluate the mating system of the remaining trees in a logged population of Swietenia macrophylla, a highly valuable and threatened hardwood species, in the Brazilian Amazon. A total of 25 open pollinated progeny arrays of 16 individuals, with their mother trees, were genotyped using eight highly polymorphic microsatellite loci. Genotypic data analysis from the progeny arrays showed that 373 out of the 400 seedlings (93.25%) were unambiguously the result of outcrossed matings and that the remaining 6.75% had genotypes consistent with self-fertilisation. Apomixis could be ruled out, since none of the 400 seedlings analysed had a multi-locus genotype identical to its mother tree. The high estimate of the multi-locus outcrossing rate (tm = 0.938 ± 0.009) using the mixed mating model also indicated that the population in this remnant stand of S. macrophylla was predominantly allogamous. The relatively large difference between the multi-locus and single-locus outcrossing estimates (tm−ts = 0.117 ± 0.011) provides evidence that, in spite of the high outcrossing rate, a considerable degree of biparental inbreeding has contributed to the genetic structure of this population. Levels of outcrossing were not evenly distributed among maternal trees (tm ranging from 0.39 to 1.00), suggesting the occurrence of a variable degree of self-incompatibility and/or dichogamy among individual trees of this monoecious species. Due to its generalist pollination system and some level of tolerance for selfing, S. macrophylla seems to be resilient to environmental disturbances such as those caused by logging, since it sets fruits with predominantly outcrossed seeds even at low stand densities. Therefore, the remaining individuals in logged areas or in relict fragments may be very important for long-term population recovery and genetic conservation programmes.

Keywords

AmazonDNA microsatellitesGenetic conservationGenetic diversityMahoganyOutcrossing

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Maristerra R. Lemes
    • 1
    • 2
  • Dario Grattapaglia
    • 3
  • James Grogan
    • 4
    • 5
  • John Proctor
    • 2
  • Rogério Gribel
    • 1
  1. 1.Laboratório de Genética e Biologia Reprodutiva de PlantasInstituto Nacional de Pesquisas da AmazôniaManausBrazil
  2. 2.School of Biological and Environmental SciencesUniversity of StirlingStirlingScotland, UK
  3. 3.Laboratório de Genética de PlantasEMBRAPA-Recursos Genéticos e BiotecnologiaBrasíliaBrazil
  4. 4.Yale University School of Forestry and Environmental StudiesNew HavenUSA
  5. 5.Instituto do Homem e Meio Ambiente da Amazônia (IMAZON)BelémBrazil