Reproductive Biology and Herkogamy of Psychotria elata (Rubiaceae), a Distylous Species of the Tropical Rain Forests of Costa Rica

Celice Alexandre Silva^1*, Jorge Arturo Lobo Segura²

¹Department of Biological Science, Centro de Pesquisas, Estudos e Desenvolvimento Agro-Ambientais (CPEDA), State University of Mato Grosso, Tangará da Serra, Brazil.
²School of Biology, University of Costa Rica, San Pedro, Costa Rica.

DOI: 10.4236/ajps.2015.63049                

Abstract

The floral morphology, breeding system and pollinators of four natural populations of Psychotria elata (Rubiaceae), found in tropical rainforests of Costa Rica, were examined. Anisoplethy and distylous morphology were observed in all studied populations. The number of flowers per inflorescence was significantly higher in the most abundant morph (p < 0.005) and the number of open flowers/inflorescence/day was similar between the morphs (p > 0.05). Reciprocal herkogamy was detected in only one of the morphs in one population. Breakdown of the heteromorphic incompatibility system was observed in the populations Tirimbina and Rara Avis. Pollen production was significantly lower in thrum morphs of Tirimbina. Seedless fruits were formed in two of the four populations. One-seeded fruits were formed in all populations and were predominant in thrum morphs of Tirimbina (9.15%) and Zurqui (75%). According to our visitation records, hummingbirds, butterflies and moths are the main pollinators of P. elata flowers.

Keywords

Disassortative Mating, Floral Morphology, Geographic Variation, Morph Ratio, Pollinators

Conflicts of Interest

The authors declare no conflicts of interest.

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