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Sunakawa Y, Mochizuki K, Kawakita A. Pollination of Oberonia japonica (Orchidaceae) by gall midges (Cecidomyiidae). Ecology 2024; 105:e4293. [PMID: 38551490 DOI: 10.1002/ecy.4293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 12/21/2023] [Accepted: 02/09/2024] [Indexed: 05/03/2024]
Affiliation(s)
- Yuta Sunakawa
- The Botanical Gardens, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Ko Mochizuki
- The Botanical Gardens, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Atsushi Kawakita
- The Botanical Gardens, Graduate School of Science, The University of Tokyo, Tokyo, Japan
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Wen H, Zhang S, Liu Y, Hu Z, Zhu C, Zeng J, Song Z, Chen J, Xu J. Screening Universal Stress-Response Terpenoids and Their Biosynthetic Genes via Volatile and Transcriptomic Profiling in Citrus. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:351-362. [PMID: 38115585 DOI: 10.1021/acs.jafc.3c06109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Volatile terpenoids accumulate in citrus and play important roles in plant defense against various stressors. However, the broad-spectrum response of terpenoid biosynthesis to ubiquitous stressors in citrus has not been comparatively investigated. In this study, volatile terpenoids were profiled under six stressors: high temperature, citrus miner, citrus red mite, citrus canker, Alternaria brown spot, and huanglongbing (HLB). Significant content changes in 15 terpenoids, including β-ocimene, were observed in more than four of the six stressors, implying their possibly universal stress-response effects. Notably, the emission of terpenoids, including β-caryophyllene, β-ocimene, and nerolidol glucoside, was significantly increased by HLB in HLB-tolerant "Shatian" pomelo leaves. The upregulation of CgTPS1 and CgTPS2 and their characterization in vivo identified them as mono- or sesquiterpenoid biosynthetic genes. This study provides a foundation for determining stress resistance mechanisms in citrus and biopesticide designations for future industrial applications.
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Affiliation(s)
- Huan Wen
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
- Sensory Evaluation and Quality Analysis Centre of Horticultural Products, Huazhong Agricultural University, Wuhan 430070, China
| | - Sining Zhang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
- Sensory Evaluation and Quality Analysis Centre of Horticultural Products, Huazhong Agricultural University, Wuhan 430070, China
| | - Yuan Liu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
- Sensory Evaluation and Quality Analysis Centre of Horticultural Products, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhehui Hu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
- Sensory Evaluation and Quality Analysis Centre of Horticultural Products, Huazhong Agricultural University, Wuhan 430070, China
| | - Congyi Zhu
- Guangdong Fruit Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
| | - Jiwu Zeng
- Guangdong Fruit Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
| | - Zhiqing Song
- Jiangxi Metallurgical Vocational and Technical College, Xinyu 338015, China
| | - Jiajing Chen
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
- Sensory Evaluation and Quality Analysis Centre of Horticultural Products, Huazhong Agricultural University, Wuhan 430070, China
| | - Juan Xu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
- Sensory Evaluation and Quality Analysis Centre of Horticultural Products, Huazhong Agricultural University, Wuhan 430070, China
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Mochizuki K, Okamoto T, Chen KH, Wang CN, Evans M, Kramer AT, Kawakita A. Adaptation to pollination by fungus gnats underlies the evolution of pollination syndrome in the genus Euonymus. ANNALS OF BOTANY 2023; 132:319-333. [PMID: 37610846 PMCID: PMC10583214 DOI: 10.1093/aob/mcad081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 07/04/2023] [Indexed: 08/25/2023]
Abstract
BACKGROUND AND AIMS Dipteran insects are known pollinators of many angiosperms, but knowledge on how flies affect floral evolution is relatively scarce. Some plants pollinated by fungus gnats share a unique set of floral characters (dark red display, flat shape and short stamens), which differs from any known pollination syndromes. We tested whether this set of floral characters is a pollination syndrome associated with pollination by fungus gnats, using the genus Euonymus as a model. METHODS The pollinator and floral colour, morphology and scent profile were investigated for ten Euonymus species and Tripterygium regelii as an outgroup. The flower colour was evaluated using bee and fly colour vision models. The evolutionary association between fungus gnat pollination and each plant character was tested using a phylogenetically independent contrast. The ancestral state reconstruction was performed on flower colour, which is associated with fungus gnat pollination, to infer the evolution of pollination in the genus Euonymus. KEY RESULTS The red-flowered Euonymus species were pollinated predominantly by fungus gnats, whereas the white-flowered species were pollinated by bees, beetles and brachyceran flies. The colour vision analysis suggested that red and white flowers are perceived as different colours by both bees and flies. The floral scents of the fungus gnat-pollinated species were characterized by acetoin, which made up >90 % of the total scent in three species. Phylogenetically independent contrast showed that the evolution of fungus gnat pollination is associated with acquisition of red flowers, short stamens and acetoin emission. CONCLUSIONS Our results suggest that the observed combination of floral characters is a pollination syndrome associated with the parallel evolution of pollination by fungus gnats. Although the role of the red floral display and acetoin in pollinator attraction remains to be elucidated, our finding underscores the importance of fungus gnats as potential contributors to floral diversification.
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Affiliation(s)
- Ko Mochizuki
- Botanical Gardens, Graduate School of Science, The University of Tokyo, 3-7-1 Hakusan, Bunkyo-ku, Tokyo, Japan
| | - Tomoko Okamoto
- Faculty of Applied Biological Sciences, Gifu University, Yanagido 1-1, Gifu, Japan
| | - Kai-Hsiu Chen
- Department of Ecology and Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Chun-Neng Wang
- Department of Life Science, Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 10617, Taiwan
| | - Matthew Evans
- Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022, USA
| | - Andrea T Kramer
- Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022, USA
| | - Atsushi Kawakita
- Botanical Gardens, Graduate School of Science, The University of Tokyo, 3-7-1 Hakusan, Bunkyo-ku, Tokyo, Japan
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Heiduk A, Brake I, Shuttleworth A, Johnson SD. 'Bleeding' flowers of Ceropegia gerrardii (Apocynaceae-Asclepiadoideae) mimic wounded insects to attract kleptoparasitic fly pollinators. THE NEW PHYTOLOGIST 2023. [PMID: 36938986 DOI: 10.1111/nph.18888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 03/14/2023] [Indexed: 06/18/2023]
Abstract
Kleptomyiophily, where flowers imitate wounded insects to attract 'kleptoparasitic' flies as pollinators, is one of the most specialized types of floral mimicry and often involves physical trapping devices. However, the diversity of pollinators and functional floral traits involved in this form of mimicry remain poorly understood. We report a novel example of kleptomyiophily in the nontrapping flowers of Ceropegia gerrardii and explore the floral traits responsible for attracting pollinators. The pollinators, reproductive biology and floral traits (including epidermal surfaces, spectral reflectance and the composition of nectariferous petal secretions and scent) were investigated. Attractive volatiles were identified using electrophysiological and behavioural experiments. Ceropegia gerrardii was predominantly pollinated by kleptoparasitic Desmometopa spp. (Milichiidae) flies. The flower corollas extrude a protein- and sugar-containing secretion, similar to the haemolymph of wounded insects, on which the flies feed. Floral scent was chemically similar to that of injured honey bees. Four out of 24 electrophysiologically active compounds, all released by injured honey bees, were identified as key players in pollinator attraction. Our results suggest that C. gerrardii flowers chemically mimic wounded honey bees to attract kleptoparasitic flies and reward them with a secretion similar to the haemolymph on which they would normally feed.
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Affiliation(s)
- Annemarie Heiduk
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa
| | | | - Adam Shuttleworth
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa
| | - Steven D Johnson
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa
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Tsz Long Wong D, Norman H, Creedy TJ, Jordaens K, Moran KM, Young A, Mengual X, Skevington JH, Vogler AP. The phylogeny and evolutionary ecology of hoverflies (Diptera: Syrphidae) inferred from mitochondrial genomes. Mol Phylogenet Evol 2023; 184:107759. [PMID: 36921697 DOI: 10.1016/j.ympev.2023.107759] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 03/01/2023] [Accepted: 03/08/2023] [Indexed: 03/16/2023]
Abstract
Hoverflies (Diptera: Syrphidae) are a diverse group of pollinators and a major research focus in ecology, but their phylogenetic relationships remain incompletely known. Using a genome skimming approach we generated mitochondrial genomes for 91 species, capturing a wide taxonomic diversity of the family. To reduce the required amount of input DNA and overall cost of the library construction, sequencing and assembly was conducted on mixtures of specimens, which raises the problem of chimera formation of mitogenomes. We present a novel chimera detection test based on gene tree incongruence, but identified only a single mitogenome of chimeric origin. Together with existing data for a final set of 127 taxa, phylogenetic analysis on nucleotide and amino acid sequences using Maximum Likelihood and Bayesian Inference revealed a basal split of Microdontinae from all other syrphids. The remainder consists of several deep clades assigned to the subfamily Eristalinae in the current classification, including a clade comprising the subfamily Syrphinae (plus Pipizinae). These findings call for a re-definition of subfamilies, but basal nodes had insufficient support to allow such action. Molecular-clock dating placed the origin of the Syrphidae crown group in the mid-Cretaceous while the Eristalinae-Syrphinae clade likely originated near the K/Pg boundary. Transformation of larval life history characters on the tree suggests that Syrphidae initially had sap feeding larvae, which diversified greatly in diet and habitat association during the Eocene and Oligocene, coinciding with the diversification of angiosperms and the evolution of various insect groups used as larval host, prey, or mimicry models. Mitogenomes proved to be a powerful phylogenetic marker for studies of Syrphidae at subfamily and tribe levels, allowing dense taxon sampling that provided insight into the great ecological diversity and rapid evolution of larval life history traits of the hoverflies.
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Affiliation(s)
- Daniel Tsz Long Wong
- Department of Life Sciences, Imperial College London, Exhibition Road, London, SW7 2BX, U.K; Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, U.K.
| | - Hannah Norman
- Department of Life Sciences, Imperial College London, Exhibition Road, London, SW7 2BX, U.K; Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, U.K.
| | - Thomas J Creedy
- Department of Life Sciences, Imperial College London, Exhibition Road, London, SW7 2BX, U.K; Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, U.K.
| | - Kurt Jordaens
- Department of Biology-Invertebrates Unit, Royal Museum for Central Africa, Joint Experimental Molecular Unit Leuvensesteenweg 13, B-3080 Tervuren, Belgium.
| | - Kevin M Moran
- Canadian National Collection of Insects, Arachnids and Nematodes, Agriculture and Agri-Food Canada, K.W. Neatby Building, 960 Carling Avenue, Ottawa, Ontario, ON K1A 0C6, Canada; Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, ON K1S 5B6, Canada.
| | - Andrew Young
- School of Environmental Sciences, University of Guelph, Guelph, Ontario, ON N1G 2W1, Canada.
| | - Ximo Mengual
- Zoologisches Forschungsmuseum Alexander Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Adenauerallee 127, 53113 Bonn, Germany.
| | - Jeffrey H Skevington
- Canadian National Collection of Insects, Arachnids and Nematodes, Agriculture and Agri-Food Canada, K.W. Neatby Building, 960 Carling Avenue, Ottawa, Ontario, ON K1A 0C6, Canada; Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, ON K1S 5B6, Canada.
| | - Alfried P Vogler
- Department of Life Sciences, Imperial College London, Exhibition Road, London, SW7 2BX, U.K; Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, U.K.
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Cardoso JCF, Johnson SD, Rezende UC, Oliveira PE. The lady's 'slippery' orchid: functions of the floral trap and aphid mimicry in a hoverfly-pollinated Phragmipedium species in Brazil. ANNALS OF BOTANY 2023; 131:275-286. [PMID: 36479901 PMCID: PMC9993062 DOI: 10.1093/aob/mcac140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 11/20/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND AND AIMS Trap flowers are fascinating cases of adaptation, often linked to oviposition-site mimicry systems. Some trap flowers do not imprison pollinators for a pre-determined period, but rather force them to move through a specific path, manipulating their movements in a way that culminates in pollen transfer, often as they leave through a secondary opening. METHODS We investigated the previously unknown pollination system of the lady's slipper orchid Phragmipedium vittatum and assessed the function of micro-morphological traits of its trap flowers. KEY RESULTS Our observations revealed that P. vittatum is pollinated by females of two hoverfly species (Syrphidae). Eggs laid by flies on or near raised black spots on the flowers indicate that the orchid mimics aphids which serve as food for their aphidophagous larvae. Dark, elevated aphid-like spots appear to attract the attention of hoverflies to a slipping zone. This region has downward projecting papillate cells and mucilage secretion that promote slipperiness, causing potential pollinators to fall into the labellum. They then follow a specific upward route towards inner aphid-like spots by holding onto upward oriented hairs that aid their grip. As hoverflies are funnelled by the lateral constriction of the labellum, they pass the stigma, depositing pollen they may be carrying. Later, they squeeze under one of the articulated anthers which places pollen smears onto their upper thorax. Then, they depart through one of the narrow lateral holes by holding onto hairs projecting from the petals. CONCLUSIONS This study confirms the system of aphid mimicry in Phragmipedium and highlights the sophisticated micro-morphological traits used by trap flowers in pollinator attraction, trapping, guidance and release, thus promoting precise pollen transfer.
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Affiliation(s)
| | - Steven D Johnson
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa
| | - Uiara C Rezende
- Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, Minas Gerais, Brazil
| | - Paulo E Oliveira
- Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, Minas Gerais, Brazil
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Perkins J, Hayashi T, Peakall R, Flematti GR, Bohman B. The volatile chemistry of orchid pollination. Nat Prod Rep 2023; 40:819-839. [PMID: 36691832 DOI: 10.1039/d2np00060a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Covering: up to September 2022Orchids are renowned not only for their diversity of floral forms, but also for their many and often highly specialised pollination strategies. Volatile semiochemicals play a crucial role in the attraction of a wide variety of insect pollinators of orchids. The compounds produced by orchid flowers are as diverse as the pollinators they attract, and here we summarise some of the chemical diversity found across orchid taxa and pollination strategies. We focus on compounds that have been experimentally demonstrated to underpin pollinator attraction. We also highlight the structural elucidation and synthesis of a select subset of important orchid pollinator attractants, and discuss the ecological significance of the discoveries, the gaps in our current knowledge of orchid pollination chemistry, and some opportunities for future research in this field.
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Affiliation(s)
- James Perkins
- Research School of Biology, The Australian National University, Australia
| | - Tobias Hayashi
- Research School of Biology, The Australian National University, Australia
| | - Rod Peakall
- Research School of Biology, The Australian National University, Australia.,School of Molecular Sciences, The University of Western Australia, Australia
| | - Gavin R Flematti
- School of Molecular Sciences, The University of Western Australia, Australia
| | - Björn Bohman
- Research School of Biology, The Australian National University, Australia.,School of Molecular Sciences, The University of Western Australia, Australia.,Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sweden.
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Yuan B, Yuan JK, Huang CG, Lian JR, Li YH, Fan XM, Yuan DY. Pseudopollen in Camellia oleifera and its implications for pollination ecology and taxonomy. FRONTIERS IN PLANT SCIENCE 2022; 13:1032187. [PMID: 36466242 PMCID: PMC9712735 DOI: 10.3389/fpls.2022.1032187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/24/2022] [Indexed: 05/24/2023]
Abstract
BACKGROUND AND AIMS In 1997, Tsou described the special differentiation of the connective tissues of some species of Theaceae to produce single-celled powders with unique patterns called pseudopollen. The purpose of this study was to investigate the morphological structure of the pseudopollen of Camellia oleifera (Theaceae) and to study the morphology of pseudopollen in seven other Camellia species. METHODS Scanning electron microscopy, paraffin section, light microscopy, transmission electron microscopy, histochemistry. KEY RESULT C. oleifera pseudopollen was similar to normal pollen in macroscopic morphology but different microscopically. The normal pollen was starch-rich and yellow, with mostly reticulate exine ornamentation. In contrast, the pseudopollen was a white powder, single-celled and rich in protein, with parallel unbranched ridge lines on the outer wall, and originated from the parenchyma of the connective tissues. There are also differences in the micro-characteristics of normal and pseudopollen among different species in Camellia. CONCLUSION There are great differences in morphological structure between C. oleifera and other species in Camellia normal pollen and pseudopollen; these results may indicate that the pseudopollen can be used as a taxonomic basis for Camellia, and the macroscopic similarity between pseudopollen and pollen and histochemical characteristics of pseudopollen can be a pollination strategy.
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Affiliation(s)
- Bin Yuan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Key Laboratory of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, China
| | - Jing-Kun Yuan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Key Laboratory of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, China
| | - Cheng-Gong Huang
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Key Laboratory of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, China
| | - Jia-Rui Lian
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Key Laboratory of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, China
| | - Yi-Huan Li
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Key Laboratory of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, China
| | - Xiao-Ming Fan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Key Laboratory of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, China
| | - De-Yi Yuan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, China
- Key Laboratory of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, China
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Qin Y, Zhang S, Li Z. Kairomonal Effect of Aphid Alarm Pheromones and Analogs on the Parasitoid Diaeretiella rapae. INSECTS 2022; 13:1055. [PMID: 36421958 PMCID: PMC9697894 DOI: 10.3390/insects13111055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/12/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
Aphid alarm pheromones, as important semiochemicals, not only mediate behavioral response of aphids, but can also act as kairomones to attract their natural enemies. The sesquiterpene (E)-β-farnesene (EβF), the major alarm pheromone component of most aphid species, has been shown to have a kairomonal effect on the predators of aphids, but other alarm pheromone components, especially the monoterpenes and analogs, are rarely investigated. Here, two EβF analogs were successfully synthesized via the nucleophilic substitution reaction, and we then examined the kairomonal effects of four alarm pheromone components and two EβF analogs on the aphid parasitoid, Diaeretiella rapae. In olfactory bioassays, D. rapae females generally showed no significant behavioral response to these alarm pheromone components and analogs under low concentrations (0.1 μg/μL). Nevertheless, their olfactory response to these compounds gradually enhanced with increasing concentrations. Among the four pheromone components, EβF showed the highest attractive activity, but the parasitoid preferred blends over single compounds. Moreover, the response time decreased as the concentration increased. We confirmed the kairomonal effect of monoterpene alarm pheromone components and their blends, in addition to EβF, on the natural enemies of aphids. This is the first report that the blend of alarm pheromone components and their analogs has a stronger kairomonal effect than do the single components on the natural enemies of aphids. This study contributes to our understanding of the mechanisms involved in the regulation of parasitoid behaviors by kairomones and provides a promising opportunity for designing kairomones for the aphid parasitoid to mediate aphid populations in the field.
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Perner H, Zhou R, Perner W, Jiang H, Lee YI. Cypripedium subtropicum embryo development and cytokinin requirements for asymbiotic germination. BOTANICAL STUDIES 2022; 63:28. [PMID: 36178517 PMCID: PMC9525480 DOI: 10.1186/s40529-022-00359-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 09/10/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Cypripedium subtropicum is a unique, endangered lady's slipper orchid with evergreen leaves on non-dormant shoots that is native to southwestern China. This study documents the major developmental events in C. subtropicum seed development from fertilization to seed maturity, determines the optimum period for seed collection, and examines the cytokinin requirements for asymbiotic germination and protocorm survival. RESULTS Structural studies revealed that embryo development proceeded after successful fertilization at 60 days after pollination (DAP). At 105 DAP, a globular embryo with the shrinking inner seed coat was observed, and seeds collected at this time point exhibited optimal germination. After 120 DAP, most seeds had a mature embryo within the capsule, and within the cells of the embryo proper, numerous proteins/lipid bodies were present as the main storage products. In addition, the inner seed coat had compressed into a thin layer that tightly enclosed the embryo, while the outer seed coat had progressively elongated, resulting in a hair-like appearance of the mature seed. Histochemical staining using Nile red and toluidine blue O (TBO) indicated that the lignified inner and outer seed coats may lead to coat-imposed dormancy. Seeds collected at this stage germinated poorly. Analyses of cytokinin preferences and optimal concentrations for germination and protocorm survival showed that both 6-(γ,γ-dimethylallylamino) purine (2iP) and 6-benzylaminopurine (BA) enhanced germination compared with the control, although higher concentrations of BA (4 and 8 μM) suppressed germination. The protocorm survival rate improved with increasing 2iP concentration. CONCLUSIONS This study provides a reproducible procedure for culturing immature seeds of C. subtropicum based on a defined time schedule of seed development. In addition, the cytokinin 2iP was shown to improve germination and protocorm survival. This study provides a scientific basis for seedling establishment through asymbiotic seed culture for further reintroduction efforts.
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Affiliation(s)
- Holger Perner
- Hengduan Mountains Biotechnology Ltd, Chengdu, 6100225, Sichuan, China
| | - Rong Zhou
- Hengduan Mountains Biotechnology Ltd, Chengdu, 6100225, Sichuan, China
| | - Wenqing Perner
- Hengduan Mountains Biotechnology Ltd, Chengdu, 6100225, Sichuan, China
| | - Hong Jiang
- Yunnan Laboratory for Conservation of Rare, Public Key Laboratory of the National Forestry and Grassland Administration, Yunnan Academy of Forestry and Grassland, Endangered & Endemic Forest Plants, Kunming, 650201, Yunnan, China.
| | - Yung-I Lee
- Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan.
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, 10617, Taiwan.
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Han ZD, Wu Y, Bernhardt P, Wang H, Ren ZX. Observations on the pollination and breeding systems of two Corybas species (Diurideae; Orchidaceae) by fungus gnats (Mycetophilidae) in southwestern Yunnan, China. BMC PLANT BIOLOGY 2022; 22:426. [PMID: 36050636 PMCID: PMC9438300 DOI: 10.1186/s12870-022-03816-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 08/26/2022] [Indexed: 06/15/2023]
Abstract
Modes of floral presentation in some angiosperms attract flies that eat and/or oviposit on seasonal fruiting bodies of fungi. Mushroom mimesis by orchid flowers has been speculated in the geoflorous, Indo-Malaysian-Australasian, genus Corybas s.l. for decades but most studies remain fragmentary and are often inconclusive. Here we report the roles of fungus gnats as pollinators of Corybas geminigibbus and C. shanlinshiensis in southwestern Yunnan, China, combining results of field observations, lab analyses, and manipulative experiments. Hand pollination experiments suggested both species were self-compatible but incapable of mechanical self-pollination, thereby requiring pollinators for fruit production. A female of a Phthinia sp. (Mycetophilidae) carried a pollinarium of C. geminigibbus dorsally on its thorax. Two females and one male of Exechia sp. (Mycetophilidae) visiting flowers of C. shanlinshiensis carried dorsal depositions of pollinaria on their thoraces. Mycetophilid eggs were not found in the flowers of either species. The comparative fragrance analyses of these flowers and three co-fruiting mushroom species did not suggest that either orchid species was a brood-site mimic. This is the first confirmation of the dispersal of pollinaria of Corybas species by fungus gnats in subtropical-temperate Asia.
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Affiliation(s)
- Zhou-Dong Han
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
| | - You Wu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
| | | | - Hong Wang
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Lijiang Forest Biodiversity National Observation and Research Station, Lijiang, China.
| | - Zong-Xin Ren
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Lijiang Forest Biodiversity National Observation and Research Station, Lijiang, China.
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Zheng CC, Luo YB, Jiao RF, Gao XF, Xu B. Cypripedium lichiangense (Orchidaceae) mimics a humus-rich oviposition site to attract its female pollinator, Ferdinandea cuprea (Syrphidae). PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:145-156. [PMID: 34490731 DOI: 10.1111/plb.13336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Most species in the genus Cypripedium (Cypripedioideae) produce trap flowers, making it a model lineage to study deceptive pollination. Floral attractants in most species studied appear to target bee species of different sizes. However, more recent publications report fly pollination in some subalpine species, suggesting novel suites of adaptive floral traits. Cypripedium lichiangense (section Trigonopedia) is an endangered subalpine species endemic to the Hengduan Mountains, China. We observed and analysed its floral traits, pollinators and breeding systems over 2 years in situ and in the lab. Cypripedium lichiangense was visited by females of Ferdinandea cuprea (Syrphidae). The pollinia were carried dorsally on the fly thoraces. The eggs of this fly were frequently found in the saccate labellum and on other floral organs, suggesting brood-site mimesis. The orchid is self-compatible, but cross-pollination produces more viable embryos. We propose a new mode of floral mimesis, humus-rich oviposition site mimicry, for C. lichiangense. Compared with the mimesis of aphid colonies attracting syrphid pollinators (subfamily Syrphinae), whose larvae are entomophagic, as reported in some Paphiopedilum species (Cypripedioideae), pollination by deceit in C. lichiangense represents a distinct and separate mode of exploitation of another saprophagic (or phytophagic) larvae syrphid lineage in the subfamily Eristalinae and appears to indicate diversity of pollination strategies in Section Trigonopedia of Cypripedium. However, this new brood-site mimesis seems to be less attractive to pollinators. As a possible adaptation to the weak attracted pollination strategy, this plant species has a long flowering period and extended lifespan of individual flowers to ensure reproductive success.
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Affiliation(s)
- C C Zheng
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Y B Luo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - R F Jiao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- Key Laboratory of Bio-Resources and Eco-Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - X F Gao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- University of Chinese Academy of Sciences, Beijing, China
| | - B Xu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- University of Chinese Academy of Sciences, Beijing, China
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Zhou Z, Shi R, Zhang Y, Xing X, Jin X. Orchid conservation in China from 2000 to 2020: Achievements and perspectives. PLANT DIVERSITY 2021; 43:343-349. [PMID: 34816060 PMCID: PMC8591184 DOI: 10.1016/j.pld.2021.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/03/2021] [Accepted: 06/11/2021] [Indexed: 06/01/2023]
Abstract
We review achievements in the conservation of orchid diversity in China over the last 21 years. We provide updated information on orchid biodiversity and suggestions for orchid conservation in China. We outline national policies of biodiversity conservation, especially of orchid conservation, which provide general guidelines for orchid conservation in China. There are now approximately 1708 known species of Orchidaceae in 181 genera in China, including five new genera and 365 new species described over the last 21 years. The assessment of risk of extinction of all 1502 known native orchid species in China in 2013 indicated that 653 species were identified as threatened, 132 species were treated as data-deficient, and four species endemic to China were classified as extinct. Approximately 1100 species (ca. 65%) are protected in national nature reserves, and another ~66 species in provincial nature reserves. About 800 native orchid species have living collections in major botanical gardens. The pollination biology of 74 native orchid species and the genetic diversity and spatial genetic structure of 29 orchid species have been investigated at a local scale and/or across species distributions. The mycorrhizal fungal community composition has been investigated in many genera, such as Bletilla, Coelogyne, Cymbidium, Cypripedium, and Dendrobium. Approximately 292 species will be included in the list of national key protected wild plants this year. Two major tasks for near future include in situ conservation and monitoring population dynamics of endangered species.
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Affiliation(s)
- Zhihua Zhou
- Department of Wildlife Conservation, National Forestry and Grassland Administration, No. 18, Hepingli Dongjie, Beijing, 100714, China
| | - Ronghong Shi
- Department of Wildlife Conservation, National Forestry and Grassland Administration, No. 18, Hepingli Dongjie, Beijing, 100714, China
| | - Yu Zhang
- Beijing Botanical Garden, Wofosi Rd, Xiangshan, Beijing, 100093, China
| | - Xiaoke Xing
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Beijing, 100193, China
| | - Xiaohua Jin
- Institute of Botany, Chinese Academy of Sciences (IBCAS), Nanxincun 20, Xiangshan, Beijing, 100093, PR China
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