Testing the influence of the myrmechocory on seed fate and plant establishment

• Autor(a) principal: Fernandes, Tiago Vinícius
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://www.locus.ufv.br/handle/123456789/21343
• topic: Formiga-cortadeira - Comportamento; Formiga-cortadeira - Ecologia; Sementes - Dispersão; Sementes - Deposição; Ecologia Teórica

Ants are considered one of the most remarkable invertebrates to disperse seeds. Seed dispersion by ants (myrmecochory) can be divided in three main phases: i) Removal; ii) Manipulation and iii) Deposition. However, all three phases have never been tested simultaneously and the contribution of each one on seed fate and seedling establishment remains unknown. In this purpose, our main aim was to determine experimentally and in field conditions the separate effect of each myrmechocory’s phase on the most critical plant stages: seed germination and seedling establishment. We choose as model organisms, the myrmecochous tree Mabea fistulifera and the leaf-cutting ant Atta sexdens. To simulate the effect of removal we used 30 distances of from the closest conspecific adult tree. To test the manipulation, in each distance we set three seed treatments levels manipulated by A. sexdens in laboratory: unmanipulated, non-scarified/without elaiosome, and scarified/without elaiosome. Finally, to test the deposition effect, we placed seed treatments over and away from ant nests. We evaluate seed germination for 90 days and seedling growth and survival for a year. We found that the increase in distance from the closest M. fistulifera adult tree decreases seed germination and increases seedling growth but have no effect on seedling survival. Moreover, neither the nest environment nor ant manipulation treatments affect seed germination, seedling growth, and survival. We experimentally showed in field conditions the role of myrmecochorous seed distancing from conspecific plants. Moreover, we suggest a life history conflict on this plant, associate to seed distancing that impairs seed germination and beneficiate seedling growth.