Breeding systems of four plant communities in the Venezuelan central plains

The goal of this study was to assess breeding systems, and inbreeding and outbreeding depression in four vegetation types in the Venezuelan central plains: forest, ecotone, savanna and disturbed areas. Such analysis allowed inferring how reproductive systems are influenced by the structure and complexity of the vegetation. This analysis was conducted considering the life form, successional stage, dispersal syndrome, pollination system specificity, and flowering time. Information on sexual systems, dichogamy and herkogamy, was also included. Experimental pollination tests were carried out on 115 plant species belonging to 41 plant families. Most species were non-agamospermous, and tended to have a mixed breeding system: partially spontaneous self-pollinated, and partially xenogamous. Xenogamous and non-spontaneous self-pollinated species were the second most frequent categories, which are represented by woody species, dispersed by frugivores or abiotically, with polyphilous and monophilous pollination systems, that flower during dry periods in the forest and forest-savanna transition. The high incidence of partial self-incompatibility was associated with herbaceous species, seed dispersal by granivores and epizoochory, and flowering throughout the rainy period in the herbaceous communities. Self-incompatibility was mainly associated with the woody condition and flower production during the dry period in forest communities. The proportion of species with inbreeding depression increased from forest to disturbed areas, and was frequently related with herbs, seed dispersal by granivores and epizoochory, and flowering during the rainy period. Outbreeding strategies and inbreeding depression increased from disturbed areas to forest along with the increase in woody life forms, frugivory and wind dispersal, and flowering during drought period.