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Introgression is widespread in the radiation of carnivorous Nepenthes pitcher plants. Mol Phylogenet Evol 2021; 163:107214. [PMID: 34052438 DOI: 10.1016/j.ympev.2021.107214] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 05/14/2021] [Accepted: 05/25/2021] [Indexed: 11/23/2022]
Abstract
Introgression and hybridization are important processes in plant evolution, but they are difficult to study from a phylogenetic perspective, because they conflict with the bifurcating evolutionary history typically depicted in phylogenetic models. The role of hybridization in plant evolution is best documented in the form of allo-polyploidizations. In contrast, homoploid hybridization and introgression are less explored, although they may be crucial in adaptive radiations. Here we employ genome-wide data (ddRAD-seq, transcriptomes) to investigate the evolutionary history of Nepenthes, a radiation of c. 160 species of iconic carnivorous plants mainly from tropical Asia. Our data indicates that the main radiation is only c. 5 million years old, and confirms previous bifurcating phylogenies. However, due to a greatly expanded number of loci, we were able test for the first time the long-standing hypotheses of introgression and historical hybridization. The genus presents one very clear case of organellar capture between two distantly related but sympatric groups. Furthermore, all Nepenthes species show introgression signals in their nuclear genomes, as uncovered by a general survey of ABBA-BABA-like statistics. The ancestor of the rapid main radiation shows ancestry from two deeply diverged lineages, as indicated by phylogenetic network analyses. All major clades of the main radiation show further introgression both within and between each other, as suggested by admixture graphs. Our study supports the hypothesis that rapid adaptive radiations are hotspots of introgression in the tree of life, and highlights the need to consider non-treelike processes in evolutionary studies of Nepenthes in particular.
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Dkhar J, Bhaskar YK, Lynn A, Pareek A. Pitchers of Nepenthes khasiana express several digestive-enzyme encoding genes, harbor mostly fungi and probably evolved through changes in the expression of leaf polarity genes. BMC PLANT BIOLOGY 2020; 20:524. [PMID: 33203377 PMCID: PMC7672872 DOI: 10.1186/s12870-020-02663-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 09/23/2020] [Indexed: 05/18/2023]
Abstract
BACKGROUND A structural phenomenon seen in certain lineages of angiosperms that has captivated many scholars including Charles Darwin is the evolution of plant carnivory. Evidently, these structural features collectively termed carnivorous syndrome, evolved to aid nutritional acquisition from attracted, captured and digested prey. We now understand why plant carnivory evolved but how carnivorous plants acquired these attributes remains a mystery. In an attempt to understand the evolution of Nepenthes pitcher and to shed more light on its role in prey digestion, we analyzed the transcriptome data of the highly specialized Nepenthes khasiana leaf comprising the leaf base lamina, tendril and the different parts/zones of the pitcher tube viz. digestive zone, waxy zone and lid. RESULTS In total, we generated around 262 million high-quality Illumina reads. Reads were pooled, normalized and de novo assembled to generate a reference transcriptome of about 412,224 transcripts. We then estimated transcript abundance along the N. khasiana leaf by mapping individual reads from each part/zone to the reference transcriptome. Correlation-based hierarchical clustering analysis of 27,208 commonly expressed genes indicated functional relationship and similar cellular processes underlying the development of the leaf base and the pitcher, thereby implying that the Nepenthes pitcher is indeed a modified leaf. From a list of 2386 differentially expressed genes (DEGs), we identified transcripts encoding key enzymes involved in prey digestion and protection against pathogen attack, some of which are expressed at high levels in the digestive zone. Interestingly, many of these enzyme-encoding genes are also expressed in the unopened N. khasiana pitcher. Transcripts showing homology to both bacteria and fungi were also detected; and in the digestive zone, fungi are more predominant as compared to bacteria. Taking cues from histology and scanning electron microscopy (SEM) photomicrographs, we found altered expressions of key regulatory genes involved in leaf development. Of particular interest, the expression of class III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIPIII) and ARGONAUTE (AGO) genes were upregulated in the tendril. CONCLUSIONS Our findings suggest that N. khasiana pitchers employ a wide range of enzymes for prey digestion and plant defense, harbor microbes and probably evolved through altered expression of leaf polarity genes.
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Affiliation(s)
- Jeremy Dkhar
- Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
- Agrotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176061 India
| | - Yogendra Kumar Bhaskar
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Andrew Lynn
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Ashwani Pareek
- Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
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Seed Total Protein Profiling in Discrimination of Closely Related Pines: Evidence from the Pinus mugo Complex. PLANTS 2020; 9:plants9070872. [PMID: 32660038 PMCID: PMC7412326 DOI: 10.3390/plants9070872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 06/29/2020] [Accepted: 07/07/2020] [Indexed: 12/24/2022]
Abstract
The Pinus mugo complex includes several dozen closely related European mountain pines. The discrimination of specific taxa within this complex is still extremely challenging, although numerous methodologies have been used to solve this problem, including morphological and anatomical analyses, cytological studies, allozyme variability, and DNA barcoding, etc. In this study, we used the seed total protein (STP) patterns to search for taxonomically interesting differences among three closely-related pine taxa from the Pinus mugo complex and five more distant species from the Pinaceae family. It was postulated that STP profiling can serve as the backup methodology for modern taxonomic research, in which more sophisticated analyses, i.e., based on the DNA barcoding approach, have been found to be useless. A quantitative analysis of the STP profiles revealed characteristic electrophoretic patterns for all the analyzed taxa from Pinaceae. STP profiling enabled the discrimination of closely-related pine taxa, even of those previously indistinguishable by chloroplast DNA barcodes. The results obtained in this study indicate that STP profiling can be very useful for solving complex taxonomic puzzles.
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Zulkapli MM, Ab Ghani NS, Ting TY, Aizat WM, Goh HH. Transcriptomic and Proteomic Analyses of Nepenthes ampullaria and Nepenthes rafflesiana Reveal Parental Molecular Expression in the Pitchers of Their Hybrid, Nepenthes × hookeriana. FRONTIERS IN PLANT SCIENCE 2020; 11:625507. [PMID: 33552113 PMCID: PMC7855304 DOI: 10.3389/fpls.2020.625507] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 12/01/2020] [Indexed: 05/18/2023]
Abstract
Nepenthes is a genus comprising carnivorous tropical pitcher plants that have evolved trapping organs at the tip of their leaves for nutrient acquisition from insect trapping. Recent studies have applied proteomics approaches to identify proteins in the pitcher fluids for better understanding the carnivory mechanism, but protein identification is hindered by limited species-specific transcriptomes for Nepenthes. In this study, the proteomics informed by transcriptomics (PIT) approach was utilized to identify and compare proteins in the pitcher fluids of Nepenthes ampullaria, Nepenthes rafflesiana, and their hybrid Nepenthes × hookeriana through PacBio isoform sequencing (Iso-Seq) and liquid chromatography-mass spectrometry (LC-MS) proteomic profiling. We generated full-length transcriptomes from all three species of 80,791 consensus isoforms with an average length of 1,692 bp as a reference for protein identification. The comparative analysis found that transcripts and proteins identified in the hybrid N. × hookeriana were more resembling N. rafflesiana, both of which are insectivorous compared with omnivorous N. ampullaria that can derive nutrients from leaf litters. Previously reported hydrolytic proteins were detected, including proteases, glucanases, chitinases, phosphatases, nucleases, peroxidases, lipid transfer protein, thaumatin-like protein, pathogenesis-related protein, and disease resistance proteins. Many new proteins with diverse predicted functions were also identified, such as amylase, invertase, catalase, kinases, ligases, synthases, esterases, transferases, transporters, and transcription factors. Despite the discovery of a few unique enzymes in N. ampullaria, we found no strong evidence of adaptive evolution to produce endogenous enzymes for the breakdown of leaf litter. A more complete picture of digestive fluid protein composition in this study provides important insights on the molecular physiology of pitchers and carnivory mechanism of Nepenthes species with distinct dietary habits.
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Wan Zakaria WNA, Aizat WM, Goh HH, Mohd Noor N. Protein replenishment in pitcher fluids of Nepenthes × ventrata revealed by quantitative proteomics (SWATH-MS) informed by transcriptomics. JOURNAL OF PLANT RESEARCH 2019; 132:681-694. [PMID: 31422552 DOI: 10.1007/s10265-019-01130-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 08/07/2019] [Indexed: 05/19/2023]
Abstract
Carnivorous plants capture and digest insects for nutrients, allowing them to survive in soil deprived of nitrogenous nutrients. Plants from the genus Nepenthes produce unique pitchers containing secretory glands, which secrete enzymes into the digestive fluid. We performed RNA-seq analysis on the pitcher tissues and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis on the pitcher fluids of Nepenthes × ventrata to study protein expression in this carnivory organ during early days of pitcher opening. This transcriptome provides a sequence database for pitcher fluid protein identification. A total of 32 proteins of diverse functions were successfully identified in which 19 proteins can be quantified based on label-free quantitative proteomics (SWATH-MS) analysis while 16 proteins were not reported previously. Our findings show that certain proteins in the pitcher fluid were continuously secreted or replenished after pitcher opening, even without any prey or chitin induction. We also discovered a new aspartic proteinase, Nep6, secreted into pitcher fluid. This is the first SWATH-MS analysis of protein expression in Nepenthes pitcher fluid using a species-specific reference transcriptome. Taken together, our study using a gel-free shotgun proteomics informed by transcriptomics (PIT) approach showed the dynamics of endogenous protein secretion in the digestive organ of N. × ventrata and provides insights on protein regulation during early pitcher opening prior to prey capture.
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Affiliation(s)
- Wan Nor Adibah Wan Zakaria
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, UKM Bangi 43600, Selangor Darul Ehsan, Malaysia
| | - Wan Mohd Aizat
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, UKM Bangi 43600, Selangor Darul Ehsan, Malaysia
| | - Hoe-Han Goh
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, UKM Bangi 43600, Selangor Darul Ehsan, Malaysia.
| | - Normah Mohd Noor
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, UKM Bangi 43600, Selangor Darul Ehsan, Malaysia
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Saganová M, Bokor B, Stolárik T, Pavlovič A. Regulation of enzyme activities in carnivorous pitcher plants of the genus Nepenthes. PLANTA 2018; 248:451-464. [PMID: 29767335 DOI: 10.1007/s00425-018-2917-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 05/11/2018] [Indexed: 05/09/2023]
Abstract
Nepenthes regulates enzyme activities by sensing stimuli from the insect prey. Protein is the best inductor mimicking the presence of an insect prey. Carnivorous plants of the genus Nepenthes have evolved passive pitcher traps for prey capture. In this study, we investigated the ability of chemical signals from a prey (chitin, protein, and ammonium) to induce transcription and synthesis of digestive enzymes in Nepenthes × Mixta. We used real-time PCR and specific antibodies generated against the aspartic proteases nepenthesins, and type III and type IV chitinases to investigate the induction of digestive enzyme synthesis in response to different chemical stimuli from the prey. Transcription of nepenthesins was strongly induced by ammonium, protein and live prey; chitin induced transcription only very slightly. This is in accordance with the amount of released enzyme and proteolytic activity in the digestive fluid. Although transcription of type III chitinase was induced by all investigated stimuli, a significant accumulation of the enzyme in the digestive fluid was found mainly after protein and live prey addition. Protein and live prey were also the best inducers for accumulation of type IV chitinase in the digestive fluid. Although ammonium strongly induced transcription of all investigated genes probably through membrane depolarization, strong acidification of the digestive fluid affected stability and abundance of both chitinases in the digestive fluid. The study showed that the proteins are universal inductors of enzyme activities in carnivorous pitcher plants best mimicking the presence of insect prey. This is not surprising, because proteins are a much valuable source of nitrogen, superior to chitin. Extensive vesicular activity was observed in prey-activated glands.
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Affiliation(s)
- Michaela Saganová
- Department of Plant Physiology, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B2, 842 15, Bratislava, Slovakia
| | - Boris Bokor
- Department of Plant Physiology, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina B2, 842 15, Bratislava, Slovakia
- Comenius University Science Park, Comenius University in Bratislava, Ilkovičova 8, 841 04, Bratislava, Slovakia
| | - Tibor Stolárik
- Department of Plant Physiology, Plant Science and Biodiversity Centre, Slovak Academy of Sciences, Dúbravská cesta 9, 845 23, Bratislava, Slovakia
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Šlechtitelů 27, 783 71, Olomouc, Czech Republic
| | - Andrej Pavlovič
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University Olomouc, Šlechtitelů 27, 783 71, Olomouc, Czech Republic.
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O'Neill MA, Denos M, Reed D. Using SDS-PAGE gel fingerprinting to identify soft-bodied wood-boring insect larvae to species. PEST MANAGEMENT SCIENCE 2018; 74:705-714. [PMID: 29044963 DOI: 10.1002/ps.4766] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 10/09/2017] [Accepted: 10/11/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND This paper describes the progress that we have made in assessing the feasibility of 'fingerprinting' using imaged SDS-PAGE gels of haemolymph proteins, to identify soft-bodied wood-boring insect larvae such as the Asian longhorn beetle, Anoplophora glabripennis (Motscholsky, 1853) (Coleoptera: Cerambycidae). Because of stringent import restrictions and difficulty in obtaining licences to work with these organisms, we opted to work with four species of scarab beetle, Mecynorhina polyphemus (Fabricius, 1781), Pachnoda sinuata (Fabricius, 1775), Eucidella shiratica (Csiki, 1909) and Eucidella shultzeorum (Kolbe, 1906) which have near identical larval morphologies. RESULTS We show that this technology when combined with an advanced pattern matching system (Digital Automated Identification SYstem - DAISY) can classify soft-bodied insect larvae that are almost identical morphologically to species at a level of accuracy is in excess of 98%. The study also indicates that the technology copes well with noisy data and small training sets. CONCLUSION The experience gained in undertaking this study gives us confidence that we will be able to develop a field deployable system in the medium term. We believe that as a high-throughput identification tool, this technology is superior to competitor technologies (e.g. fingerprinting of imaged DNA gels) in terms of speed, cost and ease of use; and therefore, is suitable for low-cost deployment in the field. © 2017 Society of Chemical Industry.
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Affiliation(s)
| | - Mia Denos
- Tumbling Dice Ltd, Newcastle upon Tyne, UK
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Rottloff S, Miguel S, Biteau F, Nisse E, Hammann P, Kuhn L, Chicher J, Bazile V, Gaume L, Mignard B, Hehn A, Bourgaud F. Proteome analysis of digestive fluids in Nepenthes pitchers. ANNALS OF BOTANY 2016; 117:479-95. [PMID: 26912512 PMCID: PMC4765550 DOI: 10.1093/aob/mcw001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 11/06/2015] [Accepted: 11/16/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS Carnivorous plants have developed strategies to enable growth in nutrient-poor soils. For the genus Nepenthes, this strategy represents producing pitcher-modified leaves that can trap and digest various prey. These pitchers produce a digestive fluid composed of proteins, including hydrolytic enzymes. The focus of this study was on the identification of these proteins. METHODS In order to better characterize and have an overview of these proteins, digestive fluid was sampled from pitchers at different stages of maturity from five species of Nepenthes (N. mirabilis, N. alata, N. sanguinea, N. bicalcarata and N. albomarginata) that vary in their ecological niches and grew under different conditions. Three complementary approaches based on transcriptomic resources, mass spectrometry and in silico analysis were used. KEY RESULTS This study permitted the identification of 29 proteins excreted in the pitchers. Twenty of these proteins were never reported in Nepenthes previously and included serine carboxypeptidases, α- and β-galactosidases, lipid transfer proteins and esterases/lipases. These 20 proteins display sequence signals allowing their secretion into the pitcher fluid. CONCLUSIONS Nepenthes pitcher plants have evolved an arsenal of enzymes to digest prey caught in their traps. The panel of new proteins identified in this study provides new insights into the digestive process of these carnivorous plants.
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Affiliation(s)
- Sandy Rottloff
- INRA UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France, Université de Lorraine UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France, Aura Optik GmbH, Hans-Knöll-Str. 6, D-07745 Jena, Germany
| | - Sissi Miguel
- Plant Advanced Technologies SA, 13 Rue du bois de la Champelle, F-54500 Vandœuvre-lès-Nancy, France
| | - Flore Biteau
- INRA UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France, Université de Lorraine UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France
| | - Estelle Nisse
- Plant Advanced Technologies SA, 13 Rue du bois de la Champelle, F-54500 Vandœuvre-lès-Nancy, France
| | - Philippe Hammann
- Plant Advanced Technologies SA, 13 Rue du bois de la Champelle, F-54500 Vandœuvre-lès-Nancy, France
| | - Lauriane Kuhn
- Proteomic Platform, Institut de Biologie Moléculaire et Cellulaire, CNRS, FRC 1589, 15 rue Descartes, F-67084 Strasbourg cedex, France and
| | - Johana Chicher
- Proteomic Platform, Institut de Biologie Moléculaire et Cellulaire, CNRS, FRC 1589, 15 rue Descartes, F-67084 Strasbourg cedex, France and
| | - Vincent Bazile
- Université Montpellier II and CNRS, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, TA A51/PS2, Bd de la Lironde, F-34398 Montpellier cedex 5, France
| | - Laurence Gaume
- Université Montpellier II and CNRS, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, TA A51/PS2, Bd de la Lironde, F-34398 Montpellier cedex 5, France
| | - Benoit Mignard
- Plant Advanced Technologies SA, 13 Rue du bois de la Champelle, F-54500 Vandœuvre-lès-Nancy, France
| | - Alain Hehn
- INRA UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France, Université de Lorraine UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France,
| | - Frédéric Bourgaud
- INRA UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France, Université de Lorraine UMR 1121, Laboratoire Agronomie et Environnement, 2 avenue de la forêt de Haye TSA 40602, F-54518 Vandœuvre-lès-Nancy, France
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Bazile V, Le Moguédec G, Marshall DJ, Gaume L. Fluid physico-chemical properties influence capture and diet in Nepenthes pitcher plants. ANNALS OF BOTANY 2015; 115:705-16. [PMID: 25672361 PMCID: PMC4343297 DOI: 10.1093/aob/mcu266] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 11/25/2014] [Accepted: 12/09/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS Nepenthes pitcher plants have evolved modified leaves with slippery surfaces and enzymatic fluids that trap and digest prey, faeces and/or plant detritus. Although the fluid's contribution to insect capture is recognized, the physico-chemical properties involved remain underexplored and may vary among species, influencing their diet type. This study investigates the contributions of acidity and viscoelasticity in the fluid's capture efficiency of two ant and two fly species in four Nepenthes species with different nutrition strategies. METHODS Four Nepenthes species were studied, namely N. rafflesiana, N. gracilis, N. hemsleyana and N. ampullaria. Fluid was collected from pitchers of varying ages from plants growing in the field and immediately transferred to glass vials, and individual ants (tribe Campotini, Fomicinae) and flies (Calliphora vomitoria and Drosophila melanogaster) were dropped in and observed for 5 min. Water-filled vials were used as controls. Survival and lifetime data were analysed using models applied to right-censored observations. Additional laboratory experiments were carried out in which C. vomitoria flies were immersed in pH-controlled aqueous solutions and observed for 5 min. KEY RESULTS Pitcher fluid differed among Nepenthes species as regards insect retention capacity and time-to-kill, with differences observed between prey types. Only the fluids of the reputedly insectivorous species were very acidic and/or viscoelastic and retained significantly more insects than the water controls. Viscoelastic fluids were fatal to flies and were able to trap the broadest diversity of insects. Younger viscoelastic fluids showed a better retention ability than older fluids, although with less rapid killing ability, suggesting that a chemical action follows a mechanical one. Insect retention increased exponentially with fluid viscoelasticity, and this happened more abruptly and at a lower threshold for flies compared with ants. Flies were more often retained if they fell into the traps on their backs, thus wetting their wings. Insect retention and death rate increased with fluid acidity, with a lower threshold for ants than for flies, and the time-to-kill decreased with increasing acidity. The laboratory experiments showed that fewer flies escaped from acidic solutions compared with water. CONCLUSIONS In addition to viscoelasticity, the pitcher's fluid acidity and wetting ability influence the fate of insects and hence the diet of Nepenthes. The plants might select the prey that they retain by manipulating the secretion of H(+) ions and polysaccharides in their pitcher fluid. This in turn might participate in possible adaptive radiation of this genus with regard to nutrient sequestration strategy. These plants might even structurally influence insect fall-orientation and capture-probability, inspiring biomimetic designs for pest control.
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Affiliation(s)
- Vincent Bazile
- Université Montpellier II, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, INRA, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, Biology Department, University of Brunei Darussalam, TungkuLink, Gadong BE 1410, Brunei Darussalam and CNRS, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France
| | - Gilles Le Moguédec
- Université Montpellier II, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, INRA, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, Biology Department, University of Brunei Darussalam, TungkuLink, Gadong BE 1410, Brunei Darussalam and CNRS, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France
| | - David J Marshall
- Université Montpellier II, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, INRA, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, Biology Department, University of Brunei Darussalam, TungkuLink, Gadong BE 1410, Brunei Darussalam and CNRS, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France
| | - Laurence Gaume
- Université Montpellier II, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, INRA, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France, Biology Department, University of Brunei Darussalam, TungkuLink, Gadong BE 1410, Brunei Darussalam and CNRS, UMR AMAP: Botanique et bioinformatique de l'architecture des plantes, CIRAD TA A51/PS2 34398 Montpellier cedex 5, France
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