Mating system parameters at hierarchical levels of fruits, individuals and populations in the Brazilian insect-pollinated tropical tree, Tabebuia roseo-alba (Bignoniaceae)

Author(s)

Feres, J. M. ^{[1, 2]} ; Sebbenn, A. M. ^[3] ; Guidugli, M. C. ^{[1, 2]} ; Mestriner, M. A. ^{[1, 2]} ; Moraes, M. L. T. ^[4] ; Alzate-Marin, A. L. ^{[1, 2]}

Affiliation

^[1] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Genet, Lab Genet Vegetal, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Dept Genet, Programa Posgrad Genet, Ribeirao Preto, SP - Brazil

^[3] Inst Florestal Sao Paulo, BR-13400970 Piracicaba, SP - Brazil

^[4] Univ Estadual Paulista, Fac Engn, Dept Fitotecnia Ilha Solteira, UNESP, BR-15385000 Ilha Solteira, SP - Brazil

• Document type: Journal article
• Source: CONSERVATION GENETICS; v. 13, n. 2, p. 393-405, 2012.
• Web of Science Citations: 19

Abstract

For many tree species, mating system analyses have indicated potential variations in the selfing rate and paternity correlation among fruits within individuals, among individuals within populations, among populations, and from one flowering event to another. In this study, we used eight microsatellite markers to investigate mating systems at two hierarchical levels (fruits within individuals and individuals within populations) for the insect pollinated Neotropical tree Tabebuia roseo-alba. We found that T. roseo-alba has a mixed mating system with predominantly outcrossed mating. The outcrossing rates at the population level were similar across two T. roseo-alba populations; however, the rates varied considerably among individuals within populations. The correlated paternity results at different hierarchical levels showed that there is a high probability of shared paternal parentage when comparing seeds within fruits and among fruits within plants and full-sibs occur in much higher proportion within fruits than among fruits. Significant levels of fixation index were found in both populations and biparental inbreeding is believed to be the main cause of the observed inbreeding. The number of pollen donors contributing to mating was low. Furthermore, open-pollinated seeds varied according to relatedness, including half-sibs, full-sibs, self-sibs and self- half-sibs. In both populations, the effective population size within a family (seed-tree and its offspring) was lower than expected for panmictic populations. Thus, seeds for ex situ conservation genetics, progeny tests and reforestation must be collected from a large number of seed-trees to guarantee an adequate effective population in the sample. (AU)

• FAPESP's process: 09/14200-6 - Genetic diversity, gene flow and mating system of Anadenathera colubrina (vell.) Brenan and Anadenanthera peregrina (L.) Speg: two species that occur in high densities in small populations in São Paulo State
• Grantee: Juliana Massimino Feres
• Support Opportunities: Scholarships in Brazil - Doctorate