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Li S, Fan J, Xue C, Shan H, Kong H. Spur development and evolution: An update. CURRENT OPINION IN PLANT BIOLOGY 2024; 81:102573. [PMID: 38896925 DOI: 10.1016/j.pbi.2024.102573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 06/21/2024]
Abstract
Floral spurs, widely recognized as a classic example of key morphological and functional innovation and thought to have promoted the origin and adaptive evolution of many flowering plant lineages, have attracted the attention of researchers for centuries. Despite this, the mechanisms underlying the development and evolution of these structures remain poorly understood. Recent studies have discovered the phytohormones and transcription factor genes that play key roles in regulating patterns of cell division and cell expansion during spur morphogenesis. Spur morphogenesis was also found to be tightly linked with the programs specifying floral zygomorphy, floral organ identity determination, and nectary development. Independent origins and losses of spurs in different flowering plant lineages, therefore, may be attributed to changes in the spur program and/or its upstream ones.
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Affiliation(s)
- Shuixian Li
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiannan Fan
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Cheng Xue
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China
| | - Hongyan Shan
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hongzhi Kong
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Sharma B, Pandher MK, Alcaraz Echeveste AQ, Romo RK, Bravo M. Delphinium as a model for development and evolution of complex zygomorphic flowers. FRONTIERS IN PLANT SCIENCE 2024; 15:1453951. [PMID: 39224845 PMCID: PMC11366623 DOI: 10.3389/fpls.2024.1453951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Accepted: 07/29/2024] [Indexed: 09/04/2024]
Abstract
The complex zygomorphic flowers of the early-diverging eudicot Delphinium provide an opportunity to explore intriguing evolutionary, developmental, and genetic questions. The dorsal perianth organs, consisting of a spurred sepal and the nectar-bearing spurred petal(s) in Delphinium, contribute to the dorso-ventralization and zygomorphic flower morphology. The seamless integration of the two or three dorsal petaloid spurred organs is considered a synorganization, and the resulting organ complex is referred to as a hyperorgan. The hyperorgan shows variability within the tribe due to variation in the number, size, and shape of the spurs. Research in recent decades within this tribe has enhanced our understanding of morphological evolution of flowers. More recently, functional studies using the RNAi approach of Virus-Induced Gene Silencing (VIGS) have unraveled interesting results highlighting the role of gene duplication in the functional diversification of organ identity and symmetry genes. Research in this early-diverging eudicot genus bridges the gaps in understanding the morphological innovations that are mostly studied in model grass and core eudicot clades. This first comprehensive review synthesizes eco-evo-devo research on Delphinium, developing a holistic understanding of recent advancements and establishing the genus as an exceptional model for addressing fundamental questions in developmental genetics, particularly in the evolution of complex flowers. This progress highlights Delphinium's significant potential for future studies in this field.
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Affiliation(s)
- Bharti Sharma
- Department of Biological Sciences, California State Polytechnic University, Pomona, CA, United States
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Lv X, Wang Y, Wang X, Zhang M, Zhang Y, Zhao L, Zhang X. Development and anatomy of petals with specialized nectar holder and pollen container in Fumarioideae (Papaveraceae). PLANTA 2024; 260:21. [PMID: 38847829 DOI: 10.1007/s00425-024-04453-8] [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: 12/19/2023] [Accepted: 05/28/2024] [Indexed: 07/03/2024]
Abstract
MAIN CONCLUSION Petal developmental characteristics in Fumarioideae were similar at early stages, and the specialized nectar holder/pollen container formed by the outer/inner petals. The micro-morphology of these two structures, however, shows diversity in seven species. Elaborate petals have been modified to form different types, including petal lobes, ridges, protuberances, and spurs, each with specialized functions. Nectar holder and pollen container presumably have a function in plant-pollinator interactions. In Fumarioideae, four elaborate petals of the disymmetric/zygomorphic flower present architecture forming the "nectar holder" and "pollen container" structure at the bottom and top separately. In the present study, the petals of seven species in Fumarioideae were investigated by scanning electron microscopy, light microscope, and transmission electron microscopes. The results show that petal development could divided into six stages: initiation, enlargement, adaxial/abaxial differentiation, elaborate specializations (sacs, spurs, and lobes formed), extension, and maturation, while the specialized "nectar holder" and "pollen container" structures mainly formed in stage 4. "Nectar holder" is developed from the shallow sac/spur differentiated at the base of the outer petal, eventually forming a multi-organized complex structure, together with staminal nectaries (1-2) with individual sizes. A semi-closed ellipsoidal "pollen container" is developed from the apical part of the 3-lobed inner petals fused by middle lobes and attain different sizes. The adaxial epidermis cells are specialized, with more distinct punctate/dense columnar protrusions or wavy cuticles presented on obviously thickening cell walls. In addition, a large and well-developed cavity appears between the inner and outer epidermis of the petals. As an exception, Hypecoum erectum middle lobes present stamen mimicry. Elaborate petal structure is crucial for comprehending the petal diversity in Fumarioideae and provides more evidence for further exploration of the reproductive study in Papaveraceae.
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Affiliation(s)
- Xuqian Lv
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Yaxi Wang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Xiaojia Wang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Mingyue Zhang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China
| | - Yuqu Zhang
- College of Pharmacy, Shaanxi University of Chinese Medicine, Xi'an, 712046, Xianyang, China
| | - Liang Zhao
- College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Xiaohui Zhang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China.
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710119, Shaanxi, China.
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Becker A, Bachelier JB, Carrive L, Conde E Silva N, Damerval C, Del Rio C, Deveaux Y, Di Stilio VS, Gong Y, Jabbour F, Kramer EM, Nadot S, Pabón-Mora N, Wang W. A cornucopia of diversity-Ranunculales as a model lineage. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1800-1822. [PMID: 38109712 DOI: 10.1093/jxb/erad492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 12/11/2023] [Indexed: 12/20/2023]
Abstract
The Ranunculales are a hyperdiverse lineage in many aspects of their phenotype, including growth habit, floral and leaf morphology, reproductive mode, and specialized metabolism. Many Ranunculales species, such as opium poppy and goldenseal, have a high medicinal value. In addition, the order includes a large number of commercially important ornamental plants, such as columbines and larkspurs. The phylogenetic position of the order with respect to monocots and core eudicots and the diversity within this lineage make the Ranunculales an excellent group for studying evolutionary processes by comparative studies. Lately, the phylogeny of Ranunculales was revised, and genetic and genomic resources were developed for many species, allowing comparative analyses at the molecular scale. Here, we review the literature on the resources for genetic manipulation and genome sequencing, the recent phylogeny reconstruction of this order, and its fossil record. Further, we explain their habitat range and delve into the diversity in their floral morphology, focusing on perianth organ identity, floral symmetry, occurrences of spurs and nectaries, sexual and pollination systems, and fruit and dehiscence types. The Ranunculales order offers a wealth of opportunities for scientific exploration across various disciplines and scales, to gain novel insights into plant biology for researchers and plant enthusiasts alike.
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Affiliation(s)
- Annette Becker
- Plant Development Group, Institute of Botany, Justus-Liebig-University, Giessen, Germany
| | - Julien B Bachelier
- Institute of Biology/Dahlem Centre of Plant Sciences, Freie Universität Berlin, D-14195 Berlin, Germany
| | - Laetitia Carrive
- Université de Rennes, UMR CNRS 6553, Ecosystèmes-Biodiversité-Evolution, Campus de Beaulieu, 35042 Rennes cedex, France
| | - Natalia Conde E Silva
- Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Génétique Quantitative et Evolution-Le Moulon, 91190 Gif-sur-Yvette, France
| | - Catherine Damerval
- Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Génétique Quantitative et Evolution-Le Moulon, 91190 Gif-sur-Yvette, France
| | - Cédric Del Rio
- CR2P - Centre de Recherche en Paléontologie - Paris, MNHN - Sorbonne Université - CNRS, 43 Rue Buffon, 75005 Paris, France
| | - Yves Deveaux
- Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Génétique Quantitative et Evolution-Le Moulon, 91190 Gif-sur-Yvette, France
| | | | - Yan Gong
- Department of Organismic and Evolutionary Biology, Harvard University, MA, 02138, USA
| | - Florian Jabbour
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier, CP39, Paris, 75005, France
| | - Elena M Kramer
- Department of Organismic and Evolutionary Biology, Harvard University, MA, 02138, USA
| | - Sophie Nadot
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie, Systématique et Evolution, Gif-sur-Yvette, France
| | - Natalia Pabón-Mora
- Instituto de Biología, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Wei Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China and University of Chinese Academy of Sciences, Beijing, 100049China
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Wang XJ, Lv XQ, Zhu QQ, Zhang XH. Diversity of staminal nectariferous appendages in disymmetric and zygomorphic flowers of Fumarioideae (Papaveraceae). PROTOPLASMA 2023; 260:1453-1467. [PMID: 37156937 DOI: 10.1007/s00709-023-01861-7] [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: 12/20/2022] [Accepted: 04/24/2023] [Indexed: 05/10/2023]
Abstract
Staminal nectaries show diversity in their position, size, shape, color, and number in Ranunculales. In Papaveraceae, nectaries only appear at the base of stamen in these lineages with disymmetric and zygomorphic flowers. However, the diversity of the staminal nectaries' developmental characteristics and structure is unknown. The diversity of staminal nectaries of Hypecoum erectum, Ichtyoselmis macrantha, Adlumia asiatica, Dactylicapnos torulosa, Corydalis edulis, and Fumaria officinalis (six species belonging to six genera, respectively) in the Fumarioideae was investigated under scanning electron microscopy, light microscopy, and transmission electron microscopy. In all species studied, according to the developmental characteristics of the nectaries, four developmental stages can be divided into initiation, enlargement, differentiation, and maturation, and the number of nectaries can be determined at the stage of initiation (stage 1), and morphological differentiation occurs at the developmental stage 3. The staminal nectaries consist of secretory epidermis, parenchyma tissue, and phloem with some sieve tube elements reaching the secretory parenchyma cells; however, the number of cell layers of parenchyma can vary from 30 to 40 in I. macrantha and D. torulosa, to only 5 to 10 like in F. officinalis. Secretory epidermis cells are larger than secretory parenchyma cells with abundant microchannels on the outer cell wall. There were abundant mitochondria, Golgi bodies, rough endoplasmic reticulum, and plastids in secretory parenchyma cells. Nectar is stored in the intercellular space and exuded to the exterior via microchannels. In A. asiatica, according to the evidence of small secretory cell characteristics such as dense cytoplasm, and numerous mitochondria, together with the filamentous secretions present on the surface of epidermal cells on groove, it can be inferred that the U-shaped sulcate which is located in the white projection formed at the filament of triplets in A. asiatica is nectariferous.
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Affiliation(s)
- Xiao-Jia Wang
- College of Life Science, Shaanxi Normal University, Xi'an, 710062, China
| | - Xu-Qian Lv
- College of Life Science, Shaanxi Normal University, Xi'an, 710062, China
| | - Qing-Qing Zhu
- College of Life Science, Shaanxi Normal University, Xi'an, 710062, China
| | - Xiao-Hui Zhang
- College of Life Science, Shaanxi Normal University, Xi'an, 710062, China.
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China.
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Zenchyzen B, Weissner S, Martin J, Lopushinsky A, John I, Nahal I, Hall JC. Comparative Nectary Morphology across Cleomaceae (Brassicales). PLANTS (BASEL, SWITZERLAND) 2023; 12:1263. [PMID: 36986951 PMCID: PMC10051628 DOI: 10.3390/plants12061263] [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: 02/09/2023] [Revised: 02/23/2023] [Accepted: 02/27/2023] [Indexed: 06/19/2023]
Abstract
Floral nectaries have evolved multiple times and rapidly diversified with the adaptive radiation of animal pollinators. As such, floral nectaries exhibit extraordinary variation in location, size, shape, and secretory mechanism. Despite the intricate ties to pollinator interactions, floral nectaries are often overlooked in morphological and developmental studies. As Cleomaceae exhibits substantial floral diversity, our objective was to describe and compare floral nectaries between and within genera. Floral nectary morphology was assessed through scanning electron microscopy and histology across three developmental stages of nine Cleomaceae species including representatives for seven genera. A modified fast green and safranin O staining protocol was used to yield vibrant sections without highly hazardous chemicals. Cleomaceae floral nectaries are most commonly receptacular, located between the perianth and stamens. The floral nectaries are supplied by vasculature, often contain nectary parenchyma, and have nectarostomata. Despite the shared location, components, and secretory mechanism, the floral nectaries display dramatic diversity in size and shape, ranging from adaxial protrusions or concavities to annular disks. Our data reveal substantive lability in form with both adaxial and annular floral nectaries interspersed across Cleomaceae. Floral nectaries contribute to the vast morphological diversity of Cleomaceae flowers and so are valuable for taxonomic descriptions. Though Cleomaceae floral nectaries are often derived from the receptacle and receptacular nectaries are common across flowering plants, the role of the receptacle in floral evolution and diversification is overlooked and warrants further exploration.
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Affiliation(s)
- Brandi Zenchyzen
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
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Zhu QQ, Xue C, Sun L, Zhong X, Zhu XX, Ren Y, Zhang XH. The diversity of elaborate petals in Isopyreae (Ranunculaceae): a special focus on nectary structure. PROTOPLASMA 2023; 260:437-451. [PMID: 35760912 DOI: 10.1007/s00709-022-01787-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 06/18/2022] [Indexed: 05/25/2023]
Abstract
Elaborate petals are highly diverse in morphology, structure, and epidermal differentiation and play a key role in attracting pollinators. There have been few studies on the elaborate structure of petals in the tribe Isopyreae (Ranunculaceae). Seven genera in Isopyreae (Aquilegia, Semiaquilegia, Urophysa, Isopyrum, Paraquilegia, Dichocarpum, and Leptopyrum) have petals that vary in morphology, and two genera (Enemion and Thalictrum) have no petals. The petals of nine species belonged to 7 genera in the tribe were studied to reveal their nectary structure, epidermal micromorphology and ancestral traits. The petal nectaries of Isopyreae examined in this study were located at the tip of spurs (Aquilegia yabeana and A. rockii), or the bottom of shallow sacs (Semiaquilegia adoxoides, Urophysa henryi, Isopyrum manshuricum, and Paraquilegia microphylla), a cup-shaped structure (Dichocarpum fargesii) and a bilabiate structure (Leptopyrum fumarioides). The petal nectary of eight species in Isopyreae (except A. ecalcarata) was composed of secretory epidermis, nectary parenchyma, and vascular tissues, and some sieve tubes reached the secretory parenchyma cells. Among the eight species with nectaries examined in the present study, A. yabeana had the most developed nectaries, with 10-15 layers of secretory parenchyma cells. The epidermal cells of mature petals of the nine species were divided into 11 types. Among these 11 types, there were two types of secretory cells and two types of trichomes. Aquilegia yabeana and A. rockii had the highest number of cell types (eight types), and I. manshuricum and L. fumarioides had the lowest number of cell types (three types). Aquilegia ecalcarata had no secretory cells, and the papillose conical polygonal secretory cells of D. fargesii were different from those of the other seven species with nectaries. Trichomes were found only in Aquilegia, Semiaquilegia, Urophysa, and Paraquilegia. The ancestral mode of nectar presentation in Isopyreae was petals with hidden nectar (70.58%). The different modes of nectar presentation in petals may reflect adaptations to different pollinators in Isopyreae.
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Affiliation(s)
- Qing-Qing Zhu
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China
- College of Life Science, Shaanxi Normal University, Xi'an, 710062, China
| | - Cheng Xue
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China
| | - Li Sun
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China
| | - Xin Zhong
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China
| | - Xin-Xin Zhu
- College of Life Sciences, Xinyang Normal University, Xinyang, 46400, China
| | - Yi Ren
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China
| | - Xiao-Hui Zhang
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China.
- College of Life Science, Shaanxi Normal University, Xi'an, 710062, China.
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Detaling morphological traits of Trollius europeus L. flowers, nectary structure, and holocrine nectar secretion through combined light and electron microscopy. Micron 2022; 162:103345. [DOI: 10.1016/j.micron.2022.103345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 08/19/2022] [Accepted: 08/24/2022] [Indexed: 11/20/2022]
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Huang Z, Zhang X. Floral nectaries and pseudonectaries in Eranthis (Ranunculaceae): petal development, micromorphology, structure and ultrastructure. PROTOPLASMA 2022; 259:1283-1300. [PMID: 35066725 DOI: 10.1007/s00709-022-01738-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
Flowers are an innovative characteristic of angiosperms, and elaborate petals usually have highly specialized structures to adapt to different living environments and pollinators. Petals of Eranthis have complex bilabiate structures with nectaries and pseudonectaries; however, the diversity of the petal micromorphology and structure is unknown. Petal development, micromorphology, structure and ultrastructure in four Eranthis species were investigated under SEM, TEM and LM. The results show that petals undergo 5 developmental stages, and accessory structure formation (stage 4) mainly determines the diversity of final mature petal morphology and pseudonectaries; the central depression formed in stage 2 will develop into nectary tissues. Petals are bilabiate and have hidden nectaries in nectary grooves; they consist of one layer of rounded and raised secretory epidermal cells and 3-14 layers of secretory cells with abundant plasmodesmata between cells. A large number of sieve tubes are distributed between the cells and extend to the epidermis; in addition, the vessel elements are located below the secretory area. Nectar is stored in the intercellular space between secretory parenchyma cells and escapes through microchannels or cell rupture. Pseudonectaries in all species of Eranthis except for E. hyemalis consist of smooth, ornamented epidermal cells and 9-12 layers of parenchyma cells with sparse cytoplasm, which may have the function of attracting pollinators.
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Affiliation(s)
- Zixuan Huang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, People's Republic of China
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, College of Life Science, Shaanxi Normal University, Xi'an, 710062, People's Republic of China
| | - Xiaohui Zhang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710119, People's Republic of China.
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, College of Life Science, Shaanxi Normal University, Xi'an, 710062, People's Republic of China.
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10
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Edwards MB, Ballerini ES, Kramer EM. Complex developmental and transcriptional dynamics underlie pollinator-driven evolutionary transitions in nectar spur morphology in Aquilegia (columbine). AMERICAN JOURNAL OF BOTANY 2022; 109:1360-1381. [PMID: 35971626 DOI: 10.1002/ajb2.16046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/17/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
PREMISE Determining the developmental programs underlying morphological variation is key to elucidating the evolutionary processes that generated the stunning biodiversity of the angiosperms. Here, we characterized the developmental and transcriptional dynamics of the elaborate petal nectar spur of Aquilegia (columbine) in species with contrasting pollination syndromes and spur morphologies. METHODS We collected petal epidermal cell number and length data across four Aquilegia species, two with short, curved nectar spurs of the bee-pollination syndrome and two with long, straight spurs of the hummingbird-pollination syndrome. We also performed RNA-seq on A. brevistyla (bee) and A. canadensis (hummingbird) distal and proximal spur compartments at multiple developmental stages. Finally, we intersected these data sets with a previous QTL mapping study on spur length and shape to identify new candidate loci. RESULTS The differential growth between the proximal and distal surfaces of curved spurs is primarily driven by differential cell division. However, independent transitions to straight spurs in the hummingbird syndrome have evolved by increasing differential cell elongation between spur surfaces. The RNA-seq data reveal these tissues to be transcriptionally distinct and point to auxin signaling as being involved with the differential cell elongation responsible for the evolution of straight spurs. We identify several promising candidate genes for future study. CONCLUSIONS Our study, taken together with previous work in Aquilegia, reveals the complexity of the developmental mechanisms underlying trait variation in this system. The framework we established here will lead to exciting future work examining candidate genes and processes involved in the rapid radiation of the genus.
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Affiliation(s)
- Molly B Edwards
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave., Cambridge, MA, 02138, USA
| | - Evangeline S Ballerini
- Department of Biological Sciences, California State University Sacramento, 6000 J St., Sacramento, CA, 95819, USA
| | - Elena M Kramer
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave., Cambridge, MA, 02138, USA
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Li WJ, Huang ZX, Han M, Ren Y, Zhang XH. Development and structure of four different stamens in Clematis macropetala (Ranunculaceae): particular emphasis on staminodes and staminal nectary. PROTOPLASMA 2022; 259:627-640. [PMID: 34247271 DOI: 10.1007/s00709-021-01687-1] [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: 03/13/2021] [Accepted: 06/29/2021] [Indexed: 05/25/2023]
Abstract
The stamens of angiosperms are diverse in number, colour and structure. The morphological and structural changes of stamens show important evolutionary significance for improving pollination efficiency. In Clematis macropetala, the androecium consists of fertile stamens and tepaloid staminodes. However, studies on the developmental features, structures and possible functions of stamens are few. In this study, the stamen ontogeny, micromorphology and nectary structure of C. macropetala were studied by scanning electron microscopy, light microscopy and transmission electron microscopy. The results indicate that the stamens can be divided into four forms according to shape and anther size: tepaloid staminode (St1), spatulate staminode (St2), linear-spatulate fertile stamen (St3) and linear fertile stamen (St4). The characteristics of stamen development are similar in the early stage but gradually differentiate in the later stage. St1 has delayed development and no anther differentiation. St2 develops abnormally at the early stage of anther differentiation. St3 and St4 are fertile, but their anther sizes are different. Nine epidermal cell types were observed in stamens, with only 4 types in St1 and 6-7 types in St2, St3 and St4. Nectary tissue appears on the adaxial side of the filament base. The nectary is composed of only one layer of secretory epidermal cells, which have a large nucleus, dense cytoplasm and well-developed wall ingrowth. Nectar is released through micro-channels in the cuticle of the outer wall. In Ranunculaceae, the staminal nectary is often located on fertile or sterile stamens, and the position, structure and micromorphology of secretory tissues of the stamen within Ranunculales are discussed.
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Affiliation(s)
- Wen-Juan Li
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China
| | - Zi-Xuan Huang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China
| | - Meng Han
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China
| | - Yi Ren
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China
| | - Xiao-Hui Zhang
- College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China.
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062, China.
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12
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Su S, Zhao L, Ren Y, Zhang XH. Diversity of petals in Berberidaceae: development, micromorphology, and structure of floral nectaries. PROTOPLASMA 2021; 258:905-922. [PMID: 33496857 DOI: 10.1007/s00709-021-01611-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
Petals are important floral organs that exhibit considerable morphological diversity in terms of colour, shape, and size. The varied morphologies of mature petals can be linked to developmental differences. The petals of Berberidaceae (a core group of Ranunculales) range from flat sheets to complex structures with nectaries, but studies on petal development and structural diversity in this group are lacking. Here, the petal development, structure, and micromorphology of seven Berberidaceae genera are characterized by microscopy to clarify the diversity of petals within this group. The results indicate that no common petal-stamen primordium exists, that petal development proceeds through five stages, and that the differentiation responsible for the diversity of the mature petals occurs during stage 4. Processes contributing to the morphological diversity of mature petals include edge thickening, gland formation, and spur formation. Nandina and Diphylleia lack nectaries. Gymnospermium has saccate nectaries, Caulophyllum has nectaries on the petal margin, Epimedium has spur nectaries, and Berberis and Mahonia have glands at the base of petals. Petal nectaries usually consist of a secretory epidermis, two to twenty layers of secretory parenchyma cells, and vascular tissues. Eleven distinct cell types were observed in the petal epidermis, three of which are secretory; papillose cells appear to be absent in Diphylleia, which shows relatively little micromorphological variation. The ancestors of Berberidaceae may have nectaries in thickened areas of their petals. The micromorphology and nectary structures of the petals in Ranunculales are also compared.
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Affiliation(s)
- Shan Su
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China
| | - Liang Zhao
- College of Life Sciences, Northwest A&F University, Yangling, 712100, China
| | - Yi Ren
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China
| | - Xiao-Hui Zhang
- Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China.
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13
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Zhang R, Min Y, Holappa LD, Walcher-Chevillet CL, Duan X, Donaldson E, Kong H, Kramer EM. A role for the Auxin Response Factors ARF6 and ARF8 homologs in petal spur elongation and nectary maturation in Aquilegia. THE NEW PHYTOLOGIST 2020; 227:1392-1405. [PMID: 32356309 DOI: 10.1111/nph.16633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/12/2020] [Indexed: 06/11/2023]
Abstract
The petal spur of the basal eudicot Aquilegia is a key innovation associated with the adaptive radiation of the genus. Previous studies have shown that diversification of Aquilegia spur length can be predominantly attributed to variation in cell elongation. However, the genetic pathways that control the development of petal spurs are still being investigated. Here, we focus on a pair of closely related homologs of the AUXIN RESPONSE FACTOR family, AqARF6 and AqARF8, to explore their roles in Aquileiga coerulea petal spur development. Expression analyses of the two genes show that they are broadly expressed in vegetative and floral organs, but have relatively higher expression in petal spurs, particularly at later stages. Knockdown of the two AqARF6 and AqARF8 transcripts using virus-induced gene silencing resulted in largely petal-specific defects, including a significant reduction in spur length due to a decrease in cell elongation. These spurs also exhibited an absence of nectar production, which was correlated with downregulation of STYLISH homologs that have previously been shown to control nectary development. This study provides the first evidence of ARF6/8 homolog-mediated petal development outside the core eudicots. The genes appear to be specifically required for cell elongation and nectary maturation in the Aquilegia petal spur.
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Affiliation(s)
- Rui Zhang
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Ya Min
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
| | - Lynn D Holappa
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
| | - Cristina L Walcher-Chevillet
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
- 10x Genomics, 6230 Stoneridge Mall Road, Pleasanton, CA, 94588-3260, USA
| | - Xiaoshan Duan
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- Harvard University Herbaria, Harvard University, 22 Divinity Ave, Cambridge, MA, 02138, USA
| | - Emily Donaldson
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
| | - Hongzhi Kong
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Elena M Kramer
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
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14
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Ballego-Campos I, Forzza RC, Paiva EAS. More than Scales: Evidence for the Production and Exudation of Mucilage by the Peltate Trichomes of Tillandsia cyanea (Bromeliaceae: Tillandsioideae). PLANTS 2020; 9:plants9060763. [PMID: 32570791 PMCID: PMC7356606 DOI: 10.3390/plants9060763] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/10/2020] [Accepted: 06/16/2020] [Indexed: 12/02/2022]
Abstract
Bromeliad scales have been investigated extensively due to their recognition as a key ecological and evolutionary feature of Bromeliaceae. However, much remains unknown about such trichomes and only recently mucilage exudation was described for them in a species of the subfamily Bromelioideae. The present study aimed to investigate the secretion present in inflorescences of Tillandsia cyanea Linden ex K. Koch (Tillandsioideae) to determine whether the scales of this species also produce and release secretions. Samples of young and mature portions of inflorescences were collected and prepared according to standard methods for light and electron microscopy. Anatomical and ultrastructural results indicate that the secretion is produced by the wing portion of typical peltate trichomes on the adaxial surface of bracts. The secretory activity begins in the early stages of trichome expansion and characteristically occurs in cells exhibiting a porous cuticle and dense cytoplasm with numerous mitochondria and dictyosomes. Histochemical tests confirmed mucilage secretion and revealed proteins in the exudate. These data comprise the first record of mucilage exudation by trichomes within Tillandsioideae and indicate that this capacity may be more relevant to bromeliad biology than previously considered. Functional aspects and colleter-like activity are also discussed.
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Affiliation(s)
- Igor Ballego-Campos
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901, Brazil;
- Correspondence:
| | - Rafaela C. Forzza
- Jardim Botânico do Rio de Janeiro, Rio de Janeiro 22460-030, Brazil;
| | - Elder A. S. Paiva
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901, Brazil;
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15
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Mesquita-Neto JN, Paiva EAS, Galetto L, Schlindwein C. Nectar Secretion of Floral Buds of Tococa guianensis Mediates Interactions With Generalist Ants That Reduce Florivory. FRONTIERS IN PLANT SCIENCE 2020; 11:627. [PMID: 32508868 PMCID: PMC7253585 DOI: 10.3389/fpls.2020.00627] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 04/23/2020] [Indexed: 06/11/2023]
Abstract
The specialised mutualism between Tococa guianensis and ants housed in its leaf domatia is a well-known example of myrmecophily. A pollination study on this species revealed that flowers in the bud stage exude a sugary solution that is collected by ants. Given the presence of this unexpected nectar secretion, we investigated how, where, and when floral buds of T. guianensis secret nectar and what function it serves. We studied a population of T. guianensis occurring in a swampy area in the Cerrado of Brazil by analyzing the chemical composition and secretion dynamics of the floral-bud nectar and the distribution and ultrastructure of secretory tissues. We also measured flower damage using ant-exclusion experiments. Floral bud nectar was secreted at the tip of the petals, which lack a typical glandular structure but possess distinctive mesophyll due to the presence of numerous calcium oxalate crystals. The nectar, the production of which ceased after flower opening, was composed mainly of sucrose and low amounts of glucose and fructose. Nectar was consumed by generalist ants and sporadically by stingless bees. Ant exclusion experiments resulted in significantly increased flower damage. The floral nectar of T. guianensis is produced during the bud stage. This bud-nectar has the extranuptial function of attracting generalist ants that reduce florivory. Pollen is the unique floral resource attracting pollinators during anthesis. Tococa guianensis, thus, establishes relationships with two functional groups of ant species: specialist ants acting against herbivory and generalist ants acting against florivory.
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Affiliation(s)
- José Neiva Mesquita-Neto
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
- Centro de Investigación en Estudios Avanzados del Maule, Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Talca, Chile
| | - Elder Antônio Sousa Paiva
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Leonardo Galetto
- Instituto Multidisciplinario de Biología Vegetal (UNC-CONICET), Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Clemens Schlindwein
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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16
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Konarska A. Microstructure of floral nectaries in Robinia viscosa var. hartwigii (Papilionoideae, Fabaceae)-a valuable but little-known melliferous plant. PROTOPLASMA 2020; 257:421-437. [PMID: 31736015 DOI: 10.1007/s00709-019-01453-4] [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: 05/16/2019] [Accepted: 10/24/2019] [Indexed: 06/10/2023]
Abstract
Floral nectaries are important components of floral architecture and significant taxonomic traits facilitating assessment of relationships between taxa and can contribute substantially to studies on the ecology and evolution of a particular genus. Knowledge of nectary structure and functioning allows better understanding of the mutualistic interactions between the pollinator and the plant. Robinia viscosa var. hartwigii (Hartweg's locust), planted in many European countries as an ornamental plant and used for recovery of degraded areas and urban arborisation, is a valuable melliferous species often visited by honeybees and bumblebees. The aim of this study was to investigate the microstructure of the floral nectaries of R. viscosa var. hartwigii with the use of light, fluorescence, scanning, and transmission electron microscopes. The photosynthetic nectaries were located on the inner surface of the cup-like receptacle. The components of pre-nectar were synthesised in the chloroplasts of the glandular parenchyma and transported via the conducting elements of the phloem. Nectar was released through modified nectarostomata. Nectar secretion presumably proceeded in the eccrine mode, whereas nectar transport represented the symplastic and apoplastic types. The cuticle on the nectary epidermis surface contained lipids, essentials oils, and flavonoids, while proteins and flavonoids were present in the glandular parenchyma cells. Idioblasts containing phenolic compounds, tannins, and polysaccharides were observed between the glandular parenchyma cells. The location of the nectaries and the mode of nectar production in the flowers of the Hartweg's locust follow the common location and structure pattern characteristic for the nectaries in some members of the subfamily Papilionoideae and can be a significant taxonomic trait for the genus Robinia and the tribe Robinieae.
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Affiliation(s)
- Agata Konarska
- Department of Botany, University of Life Sciences in Lublin, Akademicka 15, 20-950, Lublin, Poland.
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17
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Lustofin K, Świątek P, Miranda VFO, Płachno BJ. Flower nectar trichome structure of carnivorous plants from the genus butterworts Pinguicula L. (Lentibulariaceae). PROTOPLASMA 2020; 257:245-259. [PMID: 31428856 PMCID: PMC6982637 DOI: 10.1007/s00709-019-01433-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Accepted: 08/07/2019] [Indexed: 05/22/2023]
Abstract
Pinguicula (Lentibulariaceae) is a genus comprising around 96 species of herbaceous, carnivorous plants, which are extremely diverse in flower size, colour and spur length and structure as well as pollination strategy. In Pinguicula, nectar is formed in the flower spur; however, there is a gap in the knowledge about the nectary trichome structure in this genus. Our aim was to compare the nectary trichome structure of various Pinguicula species in order to determine whether there are any differences among the species in this genus. The taxa that were sampled were Pinguicula moctezumae, P. moranensis, P. rectifolia, P. emarginata and P. esseriana. We used light microscopy, histochemistry, scanning and transmission electron microscopy to address those aims. We show a conservative nectary trichome structure and spur anatomy in various Mexican Pinguicula species. The gross structural similarities between the examined species were the spur anatomy, the occurrence of papillae, the architecture of the nectary trichomes and the ultrastructure characters of the trichome cells. However, there were some differences in the spur length, the size of spur trichomes, the occurrence of starch grains in the spur parenchyma and the occurrence of cell wall ingrowths in the terminal cells of the nectary trichomes. Similar nectary capitate trichomes, as are described here, were recorded in the spurs of species from other Lentibulariaceae genera. There are many ultrastructural similarities between the cells of nectary trichomes in Pinguicula and Utricularia.
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Affiliation(s)
- Krzysztof Lustofin
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa St, 30-387, Kraków, Poland
| | - Piotr Świątek
- Department of Animal Histology and Embryology, University of Silesia in Katowice, 9 Bankowa St, 40-007, Katowice, Poland
| | - Vitor F O Miranda
- Departamento de Biologia Aplicada à Agropecuária, Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, São Paulo, Brazil
| | - Bartosz J Płachno
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa St, 30-387, Kraków, Poland.
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18
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Konarska A, Chmielewski P. Taxonomic traits in the microstructure of flowers of parasitic Orobanche picridis with particular emphasis on secretory structures. PROTOPLASMA 2020; 257:299-317. [PMID: 31529247 PMCID: PMC6982642 DOI: 10.1007/s00709-019-01438-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 08/28/2019] [Indexed: 06/01/2023]
Abstract
Orobanche picridis is an obligate root parasite devoid of chlorophyll in aboveground organs, which infects various Picris species. Given the high level of phenotypic variability of the species, the considerable limitation of the number of taxonomically relevant traits (mainly in terms of generative elements), and the low morphological variation between species, Orobanche is regarded as one of the taxonomically most problematic genera. This study aimed to analyse the taxonomic traits of O. picridis flowers with the use of stereoscopic and bright-field microscopy as well as fluorescence, scanning, and transmission electron microscopy. The micromorphology of sepals, petals, stamens, and pistils was described. For the first time, the anatomy of parasitic Orobanche nectaries and the ultrastructure of nectaries and glandular trichomes were presented. Special attention was paid to the distribution and types of glandular and non-glandular trichomes as well as the types of metabolites contained in these structures. It was demonstrated that the nectary gland was located at the base of the gynoecium and nectar was secreted through modified nectarostomata. The secretory parenchyma cells contained nuclei, large amyloplasts with starch granules, mitochondria, and high content of endoplasmic reticulum profiles. Nectar was transported via symplastic and apoplastic routes. The results of histochemical assays and fluorescence tests revealed the presence of four groups of metabolites, i.e. polyphenols (tannins, flavonoids), lipids (acidic and neutral lipids, essential oil, sesquiterpenes, steroids), polysaccharides (acidic and neutral polysaccharides), and alkaloids, in the trichomes located on perianth elements and stamens.
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Affiliation(s)
- Agata Konarska
- Department of Botany and Plant Physiology, Faculty of Horticulture and Landscape Architecture, University of Life Sciences in Lublin, Akademicka 15, 20-950, Lublin, Poland.
| | - Piotr Chmielewski
- Zamość Wildlife Association, Partyzantów 74/59, 22-400, Zamość, Poland
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19
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Min Y, Bunn JI, Kramer EM. Homologs of the STYLISH gene family control nectary development in Aquilegia. THE NEW PHYTOLOGIST 2019; 221:1090-1100. [PMID: 30145791 DOI: 10.1111/nph.15406] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 07/17/2018] [Indexed: 05/09/2023]
Abstract
Floral nectaries are an interesting example of a convergent trait in flowering plants, and are associated with the diversification of numerous angiosperm lineages, including the adaptive radiation of the New World Aquilegia species. However, we know very little as to what genes contribute to nectary development and evolution, particularly in noncore eudicot taxa. We analyzed expression patterns and used RNAi-based methods to investigate the functions of homologs from the STYLISH (STY) family in nectar spur development in Aquilegia coerulea. We found that AqSTY1 exhibits concentrated expression in the presumptive nectary of the growing spur tip, and triple gene silencing of the three STY-like genes revealed that they function in style and nectary development. Strong expression of STY homologs was also detected in the nectary-bearing petals of Delphinium and Epimedium. Our results suggest that the novel recruitment of STY homologs to control nectary development is likely to have occurred before the diversification of the Ranunculaceae and Berberidaceae. To date, the STY homologs of the Ranunculales are the only alternative loci for the control of nectary development in flowering plants, providing a critical data point in understanding the evolutionary origin and developmental basis of nectaries.
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Affiliation(s)
- Ya Min
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
| | - J Imani Bunn
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
| | - Elena M Kramer
- Department of Organismic and Evolutionary Biology, Harvard University, 16 Divinity Ave, Cambridge, MA, 02138, USA
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20
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Palmer-Young EC, Farrell IW, Adler LS, Milano NJ, Egan PA, Junker RR, Irwin RE, Stevenson PC. Chemistry of floral rewards: intra- and interspecific variability of nectar and pollen secondary metabolites across taxa. ECOL MONOGR 2018. [DOI: 10.1002/ecm.1335] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Evan C. Palmer-Young
- Department of Biology; University of Massachusetts at Amherst; Amherst Massachusetts 01003 USA
| | - Iain W. Farrell
- Royal Botanic Gardens, Kew; Richmond Surrey TW9 3AB United Kingdom
| | - Lynn S. Adler
- Department of Biology; University of Massachusetts at Amherst; Amherst Massachusetts 01003 USA
| | - Nelson J. Milano
- Department of Biology; University of Massachusetts at Amherst; Amherst Massachusetts 01003 USA
| | - Paul A. Egan
- Department of Plant Protection Biology; Swedish University of Agricultural Sciences; SE-23053 Alnarp Sweden
| | - Robert R. Junker
- Department of Bioscience; University of Salzburg; Hellbrunnerstrasse 34 5020 Salzburg Austria
| | - Rebecca E. Irwin
- Department of Applied Ecology; North Carolina State University; Raleigh North Carolina 27695 USA
| | - Philip C. Stevenson
- Royal Botanic Gardens, Kew; Richmond Surrey TW9 3AB United Kingdom
- University of Greenwich; Medway ME4 4 TB United Kingdom
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21
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Antoń S, Komoń-Janczara E, Denisow B. Floral nectary, nectar production dynamics and chemical composition in five nocturnal Oenothera species (Onagraceae) in relation to floral visitors. PLANTA 2017; 246:1051-1067. [PMID: 28779217 PMCID: PMC5653728 DOI: 10.1007/s00425-017-2748-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 07/18/2017] [Indexed: 05/09/2023]
Abstract
Main conclusion The floral nectars were sucrose-dominant; however, nectar protein and amino acid contents differed, indicating that composition of nitrogenous compounds may vary considerably even between closely related plant species, irrespectively of nectary structure. Numerous zoophilous plants attract their pollinators by offering floral nectar; an aqueous solution produced by specialized secretory tissues, known as floral nectaries. Although many papers on nectaries and nectar already exist, there has been a little research into the structure of nectaries and/or nectar production and composition in species belonging to the same genus. To redress this imbalance, we sought, in the present paper, to describe the floral nectary, nectar production, and nectar composition in five nocturnal Oenothera species with respect to their floral visitors. The structure of nectaries was similar for all the species investigated, and comprised the epidermis (with nectarostomata), numerous layers of nectary parenchyma, and subsecretory parenchyma. Anthesis for a single flower was short (ca. 10-12 h), and flowers lasted only one night. The release of floral nectar commenced at the bud stage (approx. 4 h before anthesis) and nectar was available to pollinators until petal closure. Nectar concentration was relatively low (ca. 27%) and the nectar was sucrose-dominant, and composed mainly of sucrose, glucose and fructose. The protein content of the nectar was also relatively low (on average, 0.31 µg ml-1). Nevertheless, a great variety of amino acids, including both protein and non-protein types, was detected in the nectar profile of the investigated taxa. We noted both diurnal and nocturnal generalist, opportunistic floral insect visitors.
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Affiliation(s)
- Sebastian Antoń
- Department of Botany, University of Life Sciences in Lublin, Akademicka 15, 20-950, Lublin, Poland.
| | - Elwira Komoń-Janczara
- Department of Biotechnology, Human Nutrition and Science of Food Commodities, University of Life Sciences in Lublin, Skromna 8, 20-704, Lublin, Poland
| | - Bożena Denisow
- Department of Botany, University of Life Sciences in Lublin, Akademicka 15, 20-950, Lublin, Poland
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22
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Solís SM, Zini LM, González VV, Ferrucci MS. Floral nectaries in Sapindaceae s.s.: morphological and structural diversity, and their systematic implications. PROTOPLASMA 2017; 254:2169-2188. [PMID: 28396966 DOI: 10.1007/s00709-017-1108-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 03/27/2017] [Indexed: 06/07/2023]
Abstract
We investigated the morphology and structure of the floral nectary in 11 Neotropical genera belonging to the subfamilies Dodonaeoideae and Paullinioideae (Sapindaceae) from southern South America representing three tribes (Dodonaeaeae, Paullinieae, and Melicocceae), in relation to other floral traits in species with contrasting morphological flower characteristics. Nectary organization was analyzed under light, stereoscopic, and scanning electron microscopes; Diplokeleba floribunda N.E. Br. was also observed using transmission electron microscopy. Our comparative data may contribute to the understanding of floral nectary evolution and systematic value in this family. The nectaries were studied in both staminate and pistillate flowers. All the floral nectaries are typical of Sapindaceae: extrastaminal, receptacular, structured, and persistent. The anatomical analysis revealed a differentiated secretory parenchyma and an inner non-secretory parenchyma; the nectary is supplied by phloem traces and, less frequently, by phloem and xylem traces. Nectar is secreted through nectarostomata of anomocytic type. The anatomical analysis showed the absence of nectary in the three morphs of Dodonaea viscosa flowers. Nectary ultrastructure is described in D. floribunda. In this species, the change in nectary color is related to progressive accumulation of anthocyanins during the functional phase. We found relatively small variation in the nectary structural characteristics compared with large variation in nectary morphology. The latter aspect agreed with the main infrafamilial groupings revealed by recent phylogenetic studies, so it is of current valuable systematic importance for Sapindaceae. In representatives of Paullinieae, the reduction of the floral nectary to 4-2 posterior lobes should be interpreted as a derived character state.
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Affiliation(s)
- Stella M Solís
- Facultad de Ciencias Exactas y Naturales y Agrimensura, Universidad Nacional del Nordeste, 3400, Corrientes, Argentina
- Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste, 3400, Corrientes, Argentina
| | - Lucía M Zini
- Instituto de Botánica del Nordeste (UNNE-CONICET), Corrientes, Argentina
| | - Valeria V González
- Instituto de Botánica del Nordeste (UNNE-CONICET), Corrientes, Argentina
| | - María S Ferrucci
- Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste, 3400, Corrientes, Argentina.
- Instituto de Botánica del Nordeste (UNNE-CONICET), Corrientes, Argentina.
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23
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Stevenson PC, Nicolson SW, Wright GA. Plant secondary metabolites in nectar: impacts on pollinators and ecological functions. Funct Ecol 2016. [DOI: 10.1111/1365-2435.12761] [Citation(s) in RCA: 165] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Philip C. Stevenson
- Royal Botanic Gardens, Kew SurreyTW9 3AB UK
- Natural Resources Institute University of Greenwich KentME4 4TB UK
| | - Susan W. Nicolson
- Department of Zoology & Entomology University of Pretoria Private Bag X20 Hatfield0028 South Africa
| | - Geraldine A. Wright
- Centre for Behaviour and Evolution Institute of Neuroscience Newcastle University Newcastle upon TyneNE1 7RU UK
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