Floral micromorphology of the bird-pollinated carnivorous plant species Utricularia menziesii R.Br. (Lentibulariaceae)

Made available in DSpace on 2019-10-06T16:15:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01• 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.Department of Plant Cytology and Embryology Jagiellonian University in Kraków, 9 Gronostajowa St.Faculty of Biology University of Warsaw Botanic Garden, Al. Ujazdowskie 4Department of Animal Histology and Embryology University of Silesia in Katowice, 9 Bankowa St.School of Biological Sciences University of Western Australia (M084), 35 Stirling HighwayDepartamento de Biologia Aplicada à Agropecuária Faculdade de Ciências Agrárias E Veterinárias Universidade Estadual Paulista (Unesp)Faculty of Science School of Biological Sciences University of AdelaideUnit of Botany and Plant Physiology Institute of Plant Biology and Biotechnology University of Agriculture in Kraków, 29 Listopada 54 StreetDepartamento de Biologia Aplicada à Agropecuária Faculdade de Ciências Agrárias E Veterinárias Universidade Estadual Paulista (Unesp

Floral micromorphology and nectar composition of the early evolutionary lineage Utricularia (subgenus Polypompholyx, Lentibulariaceae)

Utricularia (Lentibulariaceae) is a genus comprising around 240 species of herbaceous, carnivorous plants. Utricularia is usually viewed as an insect-pollinated genus, with the exception of a few bird-pollinated species. The bladderworts Utricularia multifida and U. tenella are interesting species because they represent an early evolutionary Utricularia branch and have some unusual morphological characters in their traps and calyx. Thus, our aims were to (i) determine whether the nectar sugar concentrations and composition in U. multifida and U. tenella are similar to those of other Utricularia species from the subgenera Polypompholyx and Utricularia, (ii) compare the nectary structure of U. multifida and U. tenella with those of other Utricularia species, and (iii) determine whether U. multifida and U. tenella use some of their floral trichomes as an alternative food reward for pollinators. We used light microscopy, histochemistry, and scanning and transmission electron microscopy to address those aims. The concentration and composition of nectar sugars were analysed using high-performance liquid chromatography. In all of the examined species, the floral nectary consisted of a spur bearing glandular trichomes. The spur produced and stored the nectar. We detected hexose-dominated (fructose + glucose) nectar in U. multifida and U. tenella as well as in U. violacea. In both U. multifida and U. tenella, there were trichomes that blocked the entrance into the throat and spur. Because these trichomes were rich in chromoplasts and contained lipid droplets, they may form an additional visual attractant. Bearing in mind the phylogenetic hypothesis for the genus, we suggest that an early ancestor of Utricularia had a nectariferous spur flower with a lower lip that formed a wide landing platform for bee pollinators

Desmopsis terriflora, an extraordinary new species of Annonaceae with flagelliflory

Flagelliflory refers to the production of inflorescences exclusively on long, whip-like branches which emerge from the main trunk and extend along the ground or below it. It is the rarest type of cauliflory and only a few cases have been reported in the world. Here, a new species of Annonaceae with flagelliflory is described and illustrated. The phylogenetic relationships of the new species were inferred using a hybrid-capture phylogenomic approach and we present some notes on its reproductive ecology and pollen characteristics. The new species, namely Desmopsis terriflora sp. nov., is part of a clade composed of Mexican species of Stenanona with long, awned petals. Desmopsis terriflora is distinguished by its flageliflorous inflorescences, basely fused sepals, thick red petals, reduced number of ovules per carpel, pollen grains with a weakly rugulate to fossulate exine ornamentation, and its globose, apiculate fruits with a woody testa. The morphological characteristics of the flagella suggest that these are specialized branches rather than inflorescences, and the absence of ramiflory implies an exclusively reproductive function. The flowers are infrequently visited by insects, their potential pollinators being flies and ants

Slowing taxon cycle can explain biodiversity patterns on islands: Insights into the biogeography of the tropical South Pacific from molecular data

International audienceIslands in the tropical Pacific Ocean are renowned for high biodiversity and endemism despite having relatively small landmasses. However, our knowledge of how this biodiversity is formed remains limited. The taxon cycle, where well‐dispersed, earlier colonizers become displaced from coastal to inland habitats by new waves of colonizers, producing isolated, range‐restricted species, has been proposed to explain current biodiversity patterns. Here, we integrate the outcomes of phylogenetic studies in the region to investigate the sources, age, number of colonizations, and diversification of 16 archipelagos in the tropical and subtropical South Pacific. We then evaluate whether the results support the taxon cycle as a plausible mechanism for these observations. We find that most species in the Pacific arrived less than 5 Mya from geographically close sources, suggesting that colonization by new taxa is a frequent and ongoing process. Therefore, our findings are broadly consistent with the theory of the Taxon Cycle, which posits that ongoing colonization results in the gradual displacement of established lineages. Only the oldest archipelagos, New Caledonia and Fiji, do not conform to this trend, having proportionally less recent colonization events, suggesting that the taxon cycle may slow on older islands. This conclusion is further validated by New Caledonia having lower diversification rate estimates than younger islands. We found that diversification rates across archipelagos are negatively correlated with area and age. Therefore, a taxon cycle that slows with island age appears to be a suitable concept for understanding the dynamic nature and biodiversity patterns of the Pacific Islands

Cluster roots are common in Daviesia and allies (Mirbelioids; fabaceae)

Cluster roots are best known in the Proteaceae, but also occur in other plant families. Cluster roots are produced by Viminaria juncea and some species of Daviesia, which belong to the Australian Mirbelioids (Fabaceae). We searched for cluster roots in a number of species in Daviesia and its close allies Gompholobium and Sphaerolobium and found them in all studied species of these three genera. Daviesia incrassata subsp. incrassata, collected at an unusually waterlogged habitat, had no cluster roots, but they were present in D. incrassata subsp. reversifolia in a drier habitat. Cluster roots are pervasive in the Daviesia group of the Fabaceae, allowing them to persist on low-phosphorus soils

Truly the best of both worlds : merging lineage‐specific and universal probe kits to maximize phylogenomic inference

Premise: Hybridization capture kits are now commonly used for reduced representation approaches in genomic sequencing, with both universal and clade‐specific kits available. Here, we present a probe kit targeting 799 low‐copy genes for the plant family Annonaceae. Methods: This new version of the kit combines the original 469 genes from the previous Annonaceae kit with 334 genes from the universal Angiosperms353 kit. We also compare the results obtained using the original Angiosperms353 kit with our custom approach using a subset of specimens. Parsimony‐informative sites and the results of maximum likelihood phylogenetic inference were assessed for combined matrices using the genera Asimina and Deeringothamnus. Results: The Annonaceae799 genes derived from the Angiosperms353 kit have extremely high recovery rates. Off‐target reads were also detected. When evaluating size, the proportion of on‐ and off‐target regions, and the number of parsimonyinformative sites, the genes incorporated from the Angiosperms353 panel generally outperformed the genes from the original Annonaceae probe kit. Discussion: We demonstrated that the new sequences from the Angiosperms353 probe set are variable and relevant for future studies on species‐level phylogenomics and within‐species studies in the Annonaceae. The integration of kits also establishes a connection between projects and makes new genes available for phylogenetic and population studies

Shared TH2 between Malawi and the Gambia.

<p>Shared TH2 between Malawi and the Gambia.</p

WebLogo of Amino Acid Sequence of Circumsporozoite Protein from Malawi and the Gambia.

<p>Panel A and Panel B are the Weblogos for Malawi and the Gambia, respectively. In Panel A, the TH2 region (blue) and TH3 region (pink) are underlined. The TH2 epitope maps almost exclusively to the α-helix, while the TH3 epitope maps to the flap. The polymorphic residues and types of amino acids that populate these sites appear to be conserved between two geographically disparate African parasite populations. Bits represent the information content, which is a relative measurement of sequence conservation, with higher values representing conservation and lower values consistent with sequence diversity at a position.</p

TH2 and TH3 Pairings from Malawi and the Gambia.

<p>(a) This figure shows all TH2-x/TH3-y haplotype pairings comparing observed and expected. Those that are that are statistically over and under represented based upon our contingency table analysis (p≤0.00009 for Malawi and p≤0.003 for the Gambia) are colored blue. (b) The data shown are for those pairings in Malawi (blue) and the Gambia (green) that are either observed >5 times in our data, or those predicted to occur >5 times based upon our contingency analysis. Each pairing is represented a unique symbol. Of note, three pairings (TH2-1/TH3-1, TH2-6/TH3-1, and TH2-3/TH3-2) were over represented in both populations. In both figures, the diagonal line represents if there were non-random association of pairings based on predicted and observed values. Points above the line represent pairing over represented in the population, while those represented below the line are those under represented in the population. A complete list of these significant pairings is provided in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0062427#pone.0062427.s005" target="_blank">Table S2</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0062427#pone.0062427.s006" target="_blank">S3</a>.</p