Bartosz J Plachno1, Malgorzata Stpiczynska2, Piotr Swiatek3, Hans Lambers4, Vitor F O Miranda5, Francis J Nge6, Piotr Stolarczyk7, Gregory R Cawthray4. 1. Department of Plant Cytology and Embryology, Jagiellonian University in Kraków, Cracow, Poland. 2. Botanic Garden, Faculty of Biology, University of Warsaw, Al. Ujazdowskie, Warsaw, Poland. 3. Department of Animal Histology and Embryology, University of Silesia in Katowice, Katowice, Poland. 4. School of Biological Sciences, University of Western Australia (M084), Crawley (Perth), WA, Australia. 5. Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, São Paulo, Brazil. 6. School of Biological Sciences, Faculty of Science, The University of Adelaide, Adelaide, South Australia, Australia. 7. Unit of Botany and Plant Physiology, Institute of Plant Biology and Biotechnology, University of Agriculture in Kraków, Kraków, Poland.
Abstract
Background and Aims: Bird pollination is rare among species in the genus Utricularia, and has evolved independently in two lineages of this genus. In Western Australia, the Western Spinebill, Acanthorhynchus superciliosus, visits flowers of Utricularia menziesii (section Pleiochasia: subgenus Polypompholyx). This study aimed to examine the micromorphology of U. menziesii flowers to assess traits that might be linked to its pollination strategy. Methods: Light microscopy, histochemistry and scanning electron microscopy were used. Nectar sugar composition was analysed using high-performance liquid chromatography. Key Results: The flowers of U. menziesii fulfil many criteria that characterize bird-pollinated flowers: red colour, a large, tough nectary spur that can withstand contact with a hard beak, lack of visual nectar guides and fragrance. Trichomes at the palate and throat may act as tactile signals. Spur nectary trichomes did not form clearly visible patches, but were more frequently distributed along vascular bundles, and were small and sessile. Each trichome comprised a single basal cell, a unicellular short pedestal cell (barrier cell) and a multicelled head. These trichomes were much smaller than those of the U. vulgaris allies. Hexose-dominated nectar was detected in flower spurs. Fructose and glucose were present in equal quantities (43 ± 3.6 and 42 ± 3.6 g L-1). Sucrose was only detected in one sample, essentially at the limit of detection for the method used. This type of nectar is common in flowers pollinated by passerine perching birds. Conclusions: The architecture of nectary trichomes in U. menziesii was similar to that of capitate trichomes of insect-pollinated species in this genus; thus, the most important specializations to bird pollination were flower colour (red), and both spur shape and size modification. Bird pollination is probably a recent innovation in the genus Utricularia, subgenus Polypompholyx, and is likely to have evolved from bee-pollinated ancestors.
Background and Aims: Bird pollination is rare among species in the genus Utricularia, and has evolved independently in two lineages of this genus. In Western Australia, the Western Spinebill, Acanthorhynchus superciliosus, visits flowers of Utricularia menziesii (section Pleiochasia: subgenus Polypompholyx). This study aimed to examine the micromorphology of U. menziesii flowers to assess traits that might be linked to its pollination strategy. Methods: Light microscopy, histochemistry and scanning electron microscopy were used. Nectar sugar composition was analysed using high-performance liquid chromatography. Key Results: The flowers of U. menziesii fulfil many criteria that characterize bird-pollinated flowers: red colour, a large, tough nectary spur that can withstand contact with a hard beak, lack of visual nectar guides and fragrance. Trichomes at the palate and throat may act as tactile signals. Spur nectary trichomes did not form clearly visible patches, but were more frequently distributed along vascular bundles, and were small and sessile. Each trichome comprised a single basal cell, a unicellular short pedestal cell (barrier cell) and a multicelled head. These trichomes were much smaller than those of the U. vulgaris allies. Hexose-dominated nectar was detected in flower spurs. Fructose and glucose were present in equal quantities (43 ± 3.6 and 42 ± 3.6 g L-1). Sucrose was only detected in one sample, essentially at the limit of detection for the method used. This type of nectar is common in flowers pollinated by passerine perching birds. Conclusions: The architecture of nectary trichomes in U. menziesii was similar to that of capitate trichomes of insect-pollinated species in this genus; thus, the most important specializations to bird pollination were flower colour (red), and both spur shape and size modification. Bird pollination is probably a recent innovation in the genus Utricularia, subgenus Polypompholyx, and is likely to have evolved from bee-pollinated ancestors.
Authors: S Abrahamczyk; M Kessler; D Hanley; D N Karger; M P J Müller; A C Knauer; F Keller; M Schwerdtfeger; A M Humphreys Journal: J Evol Biol Date: 2016-11-14 Impact factor: 2.411
Authors: Bartosz J Płachno; Saura R Silva; Piotr Świątek; Kingsley W Dixon; Krzystof Lustofin; Guilherme C Seber; Vitor F O Miranda Journal: Int J Mol Sci Date: 2020-07-21 Impact factor: 5.923
Authors: Bartosz J Płachno; Małgorzata Stpiczyńska; Piotr Świątek; Hans Lambers; Gregory R Cawthray; Francis J Nge; Saura R Silva; Vitor F O Miranda Journal: Protoplasma Date: 2019-06-12 Impact factor: 3.356
Authors: Krzysztof Lustofin; Piotr Świątek; Piotr Stolarczyk; Vitor F O Miranda; Bartosz J Płachno Journal: Ann Bot Date: 2020-10-30 Impact factor: 4.357