Paggi et al. 2015 (Conference Paper) Deuterocohnia

Pollination biology of Deuterocohnia meziana kuntz ex. Mez (Bromeliaceae) from ironstone outcrops, Mato Grosso do Sul, Brazil

Author(s):—Gecele Matos Paggi, Kelly Conceição Rondon Arruda, Diego Finati-Alves & Maurício Lenzi in Benko-Iseppon, A.M.; Alves, M. & Louzada, R. (2015) An overview and abstracts of the First World Congress on Bromeliaceae Evolution. Rodriguésia 66(2): A1-A66.

Publication:— (2015).

Abstract:—Bromeliads are perennial herbs that play important ecological functions in different environments. The familycomprises approximately 3,000 species in 58 genera and eight subfamilies. In this family the mating systems vary widely, from autonomous to obligate outcrossing species. Also, studies on phenology are important as they describe the stages of life cycles or activities in a timeline throughout a year; especially because the reproductive period is a very important phase for population dynamics and reproductive success of a species. In Bromeliaceae, ornithophily is the predominant syndrome, but melittophily, psicophily and chiropterophily also occur. Deuterocohnia meziana Kuntz ex. Mez (Pitcairnioideae) is distributed on ironstone outcrops, whereenvironmental characteristics impose inhospitable conditions on the vegetation. The plants are aggregated forming islands of vegetation, leading to increased substrate volume, which can help to reduce soil exposure allowing water conservation and mitigating the severe environmental conditions. In this study, we evaluated the pollination biology of D. meziana, considering observations of anthesis, stigma receptivity and floral visitors. To describe anthesis, two flower buds were marked at pre- anthesis in five individuals, the flower buds were observed for 12 hours to verify anthesis morphology and duration. Stigma receptivity was tested in four flowers per individual at different intervals of time during anthesis, five plants were used as replicates (n = 20). The flowers were bagged and the stigma receptivity was tested observing the catalysis activity of H2O2 (10% by volume). We observed pollinator visits for two days. Results showed that D. meziana has a period of anthesis lasting, on average, three days, from bud to complete flower opening. Stigma receptivity occurs when the flower is completely open by 7:00 am, until its closing, in the evening at 7:00 pm. Pollen is already collected in the early hours of anthesis. Hummingbirds are the most frequent visitors, followed by bees. D. meziana possibly need pollinators for sexual reproductive success, for this reason, it supplies floral resources (pollen and nectar) throughout anthesis. To prevent predation of flower buds, flowers and fruits, the species offers extra-floral resources, as do other species of bromeliads.

Keywords:—Reproductive Biology; Conservation; Bromelia.