Pollinator availability, mating system and variation in flower morphology in a tropical savanna tree

Author(s)

Rech, Andre Rodrigo ^{[1, 2]} ; Jorge, Leonardo Re ^[1] ; Ollerton, Jeff ^[3] ; Sazima, Marlies ^[1]

Affiliation

^[1] Univ Estadual Campinas, Inst Biol, BR-13083862 Campinas, SP - Brazil

^[2] Univ Fed Vales Jequitinhonha & Mucuri, Fac Interdisciplinar Humanidades, BR-39100000 Diamantina, MG - Brazil

^[3] Univ Northampton, Fac Arts Sci & Technol, Northampton NN2 6JD - England

• Document type: Journal article
• Source: Acta Botanica Brasilica; v. 32, n. 3, p. 462-472, JUL-SEP 2018.
• Web of Science Citations: 0

Abstract

ABSTRACT Widely distributed organisms face different ecological scenarios throughout their range, which can potentially lead to micro-evolutionary differentiation at specific localities. Mating systems of animal pollinated plants are supposed to evolve in response to the availability of local pollinators, with consequent changes in flower morphology. We tested the relationship among pollination , mating system, and flower morphology over a large spatial scale in Brazilian savannas using the tree Curatella americana (Dilleniaceae). We compared fruit set with and without pollinators in the field, and analyzed pollen tube growth from self- and cross-pollinated flowers in different populations. Populations with higher natural fruit set also had lower fruit set in bagged flowers, suggesting stronger barriers to self-fertilization. Furthermore, higher levels of autogamy in field experiments were associated with more pollen tubes reaching ovules in self-pollinated flowers. Morphometric studies of floral and leaf traits indicate closer-set reproductive organs, larger stigmas and smaller anthers in populations with more autogamy. We show that the spatial variation in mating system, flower morphology and pollination previously described for herbs also applies to long-lived, perennial tropical trees, thus reemphasizing that mating systems are a population-based attribute that vary according to the ecological scenario where the plants occur. (AU)

• FAPESP's process: 13/14442-5 - Pollination: ecology, evolution and conservation
• Grantee: Marlies Sazima
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• FAPESP's process: 14/16082-9 - Diversification and trophic specialization in phytophagous insects
• Grantee: Leonardo Ré Jorge
• Support Opportunities: Scholarships in Brazil - Post-Doctoral