1
|
Wan X, Wu Z, Sun D, Long L, Song Q, Gao C. Cytological characteristics of blueberry fruit development. BMC PLANT BIOLOGY 2024; 24:184. [PMID: 38475704 DOI: 10.1186/s12870-024-04809-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/08/2024] [Indexed: 03/14/2024]
Abstract
Using the blueberry cultivar "Powderblue" after pollination, fruits at different developmental stages were collected for study. The transverse and longitudinal diameters, individual fruit weight, and fruit water content were measured during their development. Employing tissue sectioning and microscopy techniques, we systematically studied the morphological features and anatomical structures of the fruits and seeds at various developmental stages, aiming to elucidate the cytological patterns during blueberry fruit development. The results of our study revealed that the "Powderblue" blueberry fruit growth and development followed a double "S" curve. Mature "Powderblue" blueberries were blue-black in color, elliptical in shape, with five locules, an inferior ovary, and an average fruit weight of 1.73 ± 0.17 g, and a moisture content of 78.865 ± 0.9%. Blueberry fruit flesh cells were densely arranged with no apparent intercellular spaces, and mesocarp cells accounted for 52.06 ± 7.4% of fruit cells. In the early fruit development stages, the fruit flesh cells were rapidly dividing, significantly increasing in number but without greatly affecting the fruit's morphological characteristics. During the later stages of fruit development, the expansion of the fruit flesh cells became prominent, resulting in a noticeable increase in the fruit's dimensions. Except for the epidermal cells, cells in all fruit tissues showed varying degrees of rupture as fruit development progressed, with the extent of cell rupture increasing, becoming increasingly apparent as the fruit gradually softened. Additionally, numerous brachysclereids (stone cells) appeared in the fruit flesh cells. Stone cells are mostly present individually in the fruit flesh tissue, while in the placental tissue, they often group together. The "Powderblue" blueberry seeds were light brown, 4.13 ± 0.42 mm long, 2.2 ± 0.14 mm wide, with each fruit containing 50-60 seeds. The "Powderblue" seeds mainly consisted of the seed coat, endosperm, and embryo. The embryo was located at the chalazal end in the center of the endosperm and was spatially separated. The endosperm, occupying the vast majority of the seed volume, comprised both the chalazal and outer endosperm, and the endosperm developed and matured before the embryo. As the seed developed, the seed coat was gradually lignified and consisted of palisade-like stone cells externally and epidermal layer cells internally.
Collapse
Affiliation(s)
- Xianqin Wan
- Institute for Forest Resources and Environment of Guizhou, Key laboratory of forest cultivation in plateau mountain of Guizhou province, College of Forestry, Guizhou University, Guiyang, 550025, China
| | - Zewei Wu
- Institute for Forest Resources and Environment of Guizhou, Key laboratory of forest cultivation in plateau mountain of Guizhou province, College of Forestry, Guizhou University, Guiyang, 550025, China
| | - Dongchan Sun
- Institute for Forest Resources and Environment of Guizhou, Key laboratory of forest cultivation in plateau mountain of Guizhou province, College of Forestry, Guizhou University, Guiyang, 550025, China
| | - Li Long
- Institute for Forest Resources and Environment of Guizhou, Key laboratory of forest cultivation in plateau mountain of Guizhou province, College of Forestry, Guizhou University, Guiyang, 550025, China
| | - Qiling Song
- Institute for Forest Resources and Environment of Guizhou, Key laboratory of forest cultivation in plateau mountain of Guizhou province, College of Forestry, Guizhou University, Guiyang, 550025, China
| | - Chao Gao
- Institute for Forest Resources and Environment of Guizhou, Key laboratory of forest cultivation in plateau mountain of Guizhou province, College of Forestry, Guizhou University, Guiyang, 550025, China.
| |
Collapse
|
2
|
Zhang L, Kamitakahara H, Takano T, Morimoto T, Sakamoto S, Mitsuda N, Itai A. Stone cell formation in the pedicel of pears and apples. PLANTA 2023; 258:85. [PMID: 37747516 DOI: 10.1007/s00425-023-04240-x] [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: 04/07/2023] [Accepted: 09/13/2023] [Indexed: 09/26/2023]
Abstract
MAIN CONCLUSION For the first time, stone cells in pear and apple pedicel were studied. The lignification of the pedicel outer part was correlated with flesh, and the secondary cell wall biosynthesis genes were activated. Fruit pedicels act as bridges between the fruit and the shoot. They have secondary thickened cell walls that presumably function in mechanical support, water and nutrient transport. Stone cells are cells with a secondary cell wall thickening. In pears, yet not in apples, the stone cells affect the flesh texture. There have been few reports on stone cell formation in pear and apple pedicels; therefore, we studied these cells for the first time. The apple pedicel had few stone cells in the cortex. The formation of stone cells in pear continued until seven weeks after flowering (WAF), and the density was significantly higher than in apple. The stone cell formation degree (SFD) of pear was 3.6-7.1 times higher than that of apple. Total lignin and lignin non-condensed structure (G and S units) content in the pear pedicle outer part was 1.5-2.7 times higher than that of the apple at harvest. The SFD of the pedicel outer part had a positive correlation with the G and S units content of the flesh. The total lignin and G and S units content between flesh and the pedicel outer part were positively correlated. Correlation analysis revealed a positive relationship between fruit and pedicel formation of the stone cells. The WGCNA showed that NST3 was linked to NAC028, MYB46, CESA, POD, LAC, and VSR6. These genes were highly expressed in the outer part of the pear pedicel, while they were suppressed in that issue of the apple at 4 WAF.
Collapse
Affiliation(s)
- Lumin Zhang
- Tropical Eco-Agriculture Research Institute, Yunnan Academy of Agricultural Sciences, Nancheng Street 150, Yuanmou, 651300, Yunnan, China
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kitaina-Yazuma Oji 74, Seika-Cho, Soraku-Gun, Kyoto, 619-0244, Japan
| | - Hiroshi Kamitakahara
- Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-Cho, Sakyo-Ku, Kyoto, 606-8502, Japan
| | - Toshiyuki Takano
- Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-Cho, Sakyo-Ku, Kyoto, 606-8502, Japan
| | - Takuya Morimoto
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kitaina-Yazuma Oji 74, Seika-Cho, Soraku-Gun, Kyoto, 619-0244, Japan
| | - Shingo Sakamoto
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan
| | - Nobutaka Mitsuda
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan
| | - Akihiro Itai
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kitaina-Yazuma Oji 74, Seika-Cho, Soraku-Gun, Kyoto, 619-0244, Japan.
| |
Collapse
|
3
|
Raman Method in Identification of Species and Varieties, Assessment of Plant Maturity and Crop Quality—A Review. Molecules 2022; 27:molecules27144454. [PMID: 35889327 PMCID: PMC9322835 DOI: 10.3390/molecules27144454] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/08/2022] [Accepted: 07/11/2022] [Indexed: 02/05/2023] Open
Abstract
The present review covers reports discussing potential applications of the specificity of Raman techniques in the advancement of digital farming, in line with an assumption of yield maximisation with minimum environmental impact of agriculture. Raman is an optical spectroscopy method which can be used to perform immediate, label-free detection and quantification of key compounds without destroying the sample. The authors particularly focused on the reports discussing the use of Raman spectroscopy in monitoring the physiological status of plants, assessing crop maturity and quality, plant pathology and ripening, and identifying plant species and their varieties. In recent years, research reports have presented evidence confirming the effectiveness of Raman spectroscopy in identifying biotic and abiotic stresses in plants as well as in phenotyping and digital selection of plants in farming. Raman techniques used in precision agriculture can significantly improve capacities for farming management, crop quality assessment, as well as biological and chemical contaminant detection, thereby contributing to food safety as well as the productivity and profitability of agriculture. This review aims to increase the awareness of the growing potential of Raman spectroscopy in agriculture among plant breeders, geneticists, farmers and engineers.
Collapse
|
4
|
Saletnik A, Saletnik B, Puchalski C. Overview of Popular Techniques of Raman Spectroscopy and Their Potential in the Study of Plant Tissues. Molecules 2021; 26:1537. [PMID: 33799702 PMCID: PMC7999012 DOI: 10.3390/molecules26061537] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 01/15/2023] Open
Abstract
Raman spectroscopy is one of the main analytical techniques used in optical metrology. It is a vibration, marker-free technique that provides insight into the structure and composition of tissues and cells at the molecular level. Raman spectroscopy is an outstanding material identification technique. It provides spatial information of vibrations from complex biological samples which renders it a very accurate tool for the analysis of highly complex plant tissues. Raman spectra can be used as a fingerprint tool for a very wide range of compounds. Raman spectroscopy enables all the polymers that build the cell walls of plants to be tracked simultaneously; it facilitates the analysis of both the molecular composition and the molecular structure of cell walls. Due to its high sensitivity to even minute structural changes, this method is used for comparative tests. The introduction of new and improved Raman techniques by scientists as well as the constant technological development of the apparatus has resulted in an increased importance of Raman spectroscopy in the discovery and defining of tissues and the processes taking place in them.
Collapse
Affiliation(s)
| | - Bogdan Saletnik
- Department of Bioenergetics, Food Analysis and Microbiology, Institute of Food Technology and Nutrition, College of Natural Sciences, University of Rzeszów, Ćwiklińskiej 2D, 35-601 Rzeszów, Poland; (A.S.); (C.P.)
| | | |
Collapse
|
5
|
Lautenschläger T, Rüggeberg M, Noack N, Bunk K, Mawunu M, Speck T, Neinhuis C. Functional principles of baobab fruit pedicels - anatomy and biomechanics. ANNALS OF BOTANY 2020; 126:1215-1223. [PMID: 32808645 PMCID: PMC7684697 DOI: 10.1093/aob/mcaa149] [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: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND AIMS Fruit pedicels have to deal with increasing loads after pollination due to continuous growth of the fruits. Thus, they represent interesting tissues from a mechanical as well as a developmental point of view. However, only a few studies exist on fruit pedicels. In this study, we unravel the anatomy and structural-mechanical relationships of the pedicel of Adansonia digitata, reaching up to 90 cm in length. METHODS Morphological and anatomical analyses included examination of stained cross-sections from various positions along the stalk as well as X-ray microtomography and scanning electron microscopy. For mechanical testing, fibre bundles derived from the mature pedicels were examined via tension tests. For establishing the structural-mechanical relationships, the density of the fibre bundles as well as their cellulose microfibril distribution and chemical composition were analysed. KEY RESULTS While in the peduncle the vascular tissue and the fibres are arranged in a concentric ring-like way, this organization shifts to the polystelic structure of separate fibre bundles in the pedicel. The polystelic pedicel possesses five vascular strands that consist of strong bast fibre bundles. The fibre bundles have a Young's modulus of up to 5 GPa, a tensile strength of up to 400 MPa, a high density (>1 g cm-3) and a high microfibril angle of around 20°. CONCLUSIONS The structural arrangement as well as the combination of high density and high microfibril angle of the bast fibre bundles are probably optimized for bearing considerable strain in torsion and bending while at the same time allowing for carrying high-tension loads.
Collapse
Affiliation(s)
- Thea Lautenschläger
- Department of Biology, Institute of Botany, Faculty of Science, Technische Universität Dresden, Germany
| | | | - Niclas Noack
- Department of Biology, Institute of Botany, Faculty of Science, Technische Universität Dresden, Germany
| | - Katharina Bunk
- Plant Biomechanics Group & Botanic Garden, University of Freiburg, Germany
- Freiburger Zentrum für interaktive Werkstoffe und bioinspirierte Technologien, Germany
| | - Monizi Mawunu
- Department of Agronomy, Kimpa Vita University, Uíge, Angola
| | - Thomas Speck
- Plant Biomechanics Group & Botanic Garden, University of Freiburg, Germany
- Freiburger Zentrum für interaktive Werkstoffe und bioinspirierte Technologien, Germany
| | - Christoph Neinhuis
- Department of Biology, Institute of Botany, Faculty of Science, Technische Universität Dresden, Germany
| |
Collapse
|
6
|
Vázquez C, Carmo-Sousa M, Lopes JRS, Fereres A, Moreno A. Aphids Are Unable to Ingest Phloem Sap from the Peduncles of Lime Fruits. PLANTS 2020; 9:plants9111528. [PMID: 33182608 PMCID: PMC7696807 DOI: 10.3390/plants9111528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/04/2020] [Accepted: 11/06/2020] [Indexed: 12/04/2022]
Abstract
Citrus exports to Europe are regulated enforcing that fruits shall be free from peduncles and leaves, as they represent an important pathway for the entrance of non-European (non-EU) Citrus tristeza virus (CTV) isolates into the European Community. Aphids, are the vectors of CTV and could potentially feed on peduncles of imported fruits and thus spread non-EU isolates of CTV across Europe. We studied the probing behaviour of the main vectors of CTV (Aphis (Toxoptera) citricidus and Aphis gossypii) on lime leaves and peduncles to assess whether they could potentially transmit the virus. Aphids placed on peduncles rejected probing and feeding, tried to escape and spent most of their time on non-probing activities. Our work demonstrated that both A. citricidus and A. gossypii could not ingest sap from the phloem of lime peduncles, as phloem ingestion was never observed. This implies that aphids would not be able to acquire CTV from an infected fruit peduncle and transmit it to a susceptible plant. Our study supports that citrus exports with fruit peduncles to Europe may not be a real risk for the introduction of non-EU isolates of CTV to the European Community.
Collapse
Affiliation(s)
- Carolina Vázquez
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, ICA-CSIC, 28006 Madrid, Spain;
| | - Michele Carmo-Sousa
- Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba SP 13418-900, Brazil; (M.C.-S.);
(J.R.S.L.)
| | - Joao Roberto Spotti Lopes
- Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba SP 13418-900, Brazil; (M.C.-S.);
(J.R.S.L.)
| | - Alberto Fereres
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, ICA-CSIC, 28006 Madrid, Spain;
- Correspondence: (A.F.); (A.M.)
| | - Aranzazu Moreno
- Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, ICA-CSIC, 28006 Madrid, Spain;
- Correspondence: (A.F.); (A.M.)
| |
Collapse
|
7
|
Dinant S, Wolff N, De Marco F, Vilaine F, Gissot L, Aubry E, Sandt C, Bellini C, Le Hir R. Synchrotron FTIR and Raman spectroscopy provide unique spectral fingerprints for Arabidopsis floral stem vascular tissues. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:871-884. [PMID: 30407539 DOI: 10.1093/jxb/ery396] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 10/30/2018] [Indexed: 05/22/2023]
Abstract
Cell walls are highly complex structures that are modified during plant growth and development. For example, the development of phloem and xylem vascular cells, which participate in the transport of sugars and water as well as providing support, can be influenced by cell-specific wall composition. Here, we used synchrotron radiation-based Fourier-transform infrared (SR-FTIR) and Raman spectroscopy to analyse the cell wall composition of floral stem vascular tissues of wild-type Arabidopsis and the double-mutant sweet11-1 sweet12-1, which has impaired sugar transport. The SR-FTIR spectra showed that in addition to modified xylem cell wall composition, phloem cell walls in the double-mutant line were characterized by modified hemicellulose composition. Combining Raman spectroscopy with a classification and regression tree (CART) method identified combinations of Raman shifts that could distinguish xylem vessels and fibers. In addition, the disruption of the SWEET11 and SWEET12 genes impacted on xylem wall composition in a cell-specific manner, with changes in hemicelluloses and cellulose observed at the xylem vessel interface. These results suggest that the facilitated transport of sugars by transporters that exist between vascular parenchyma cells and conducting cells is important in ensuring correct phloem and xylem cell wall composition.
Collapse
Affiliation(s)
- S Dinant
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
| | - N Wolff
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
| | - F De Marco
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
| | - F Vilaine
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
| | - L Gissot
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
| | - E Aubry
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
| | - C Sandt
- Synchrotron SOLEIL, Ligne SMIS, L'Orme des Merisiers, Gif sur Yvette, France
| | - C Bellini
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - R Le Hir
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay,Versailles, France
| |
Collapse
|
8
|
Crespo-Martínez S, Sobczak M, Różańska E, Forneck A, Griesser M. The role of the secondary phloem during the development of the grapevine Berry Shrivel ripening disorder. Micron 2018; 116:36-45. [PMID: 30292168 DOI: 10.1016/j.micron.2018.09.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 09/23/2018] [Accepted: 09/23/2018] [Indexed: 01/26/2023]
Abstract
Berry Shrivel (BS) is a post-veraison physiological ripening disorder of grapevine berries. Its symptoms encompass low pH, reduced content of sugars and anthocyanins, and loss of turgor leading to berries shriveling. Evidence for the primary causes of BS is still speculative and anatomical studies are scarce. So far, anatomical studies have determined necrotic cells, degraded primary phloem cells and hardening of secondary phloem cells in the rachis of BS affected grapes. The picture is far from being complete. Herein we report in-depth analyses of the ultrastructure, anatomy and spatial elementary analysis of rachis and pedicel tissues of BS symptomatic grape clusters with different symptom severity. We hypothesize that structural changes in the vascular system of BS affected grape clusters could alter transport functions of the phloem tissue and contribute to the appearance of BS symptoms. By applying different microscopic techniques (LM, SEM, TEM and EDS) we found a number of anatomical differences in both, rachis and pedicels, between H and BS symptomatic grapes, which include: (i) extended areas of collapsed cells and cell wall thickenings in the secondary phloem in BS samples; (ii) reduced number of cell layers in the cambium in BS samples; (iii) higher rate of callose deposition on sieve plates that are additionally covered with a carbohydrate-like material in BS samples; and (iv) reduced (up to 60%) estimated sieve tube conductivity in BS samples.
Collapse
Affiliation(s)
- Sara Crespo-Martínez
- University of Natural Resources and Life Sciences Vienna, Department of Crop Sciences, Division of Viticulture and Pomology. UFT Tulln, Konrad Lorenzstrasse 24, A-3430, Tulln, Austria.
| | - Mirosław Sobczak
- Warsaw University of Life Sciences (SGGW), Faculty of Agriculture and Biology, Department of Botany, Nowoursynowska 159, Building 37, 02-776, Warsaw, Poland
| | - Elżbieta Różańska
- Warsaw University of Life Sciences (SGGW), Faculty of Agriculture and Biology, Department of Botany, Nowoursynowska 159, Building 37, 02-776, Warsaw, Poland
| | - Astrid Forneck
- University of Natural Resources and Life Sciences Vienna, Department of Crop Sciences, Division of Viticulture and Pomology. UFT Tulln, Konrad Lorenzstrasse 24, A-3430, Tulln, Austria
| | - Michaela Griesser
- University of Natural Resources and Life Sciences Vienna, Department of Crop Sciences, Division of Viticulture and Pomology. UFT Tulln, Konrad Lorenzstrasse 24, A-3430, Tulln, Austria
| |
Collapse
|
9
|
Horbens M, Branke D, Gärtner R, Voigt A, Stenger F, Neinhuis C. Multi-scale simulation of plant stem reinforcement by brachysclereids: A case study in apple fruit peduncles. J Struct Biol 2015; 192:116-26. [DOI: 10.1016/j.jsb.2015.08.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 07/25/2015] [Accepted: 08/06/2015] [Indexed: 10/23/2022]
|
10
|
Knipfer T, Fei J, Gambetta GA, McElrone AJ, Shackel KA, Matthews MA. Water Transport Properties of the Grape Pedicel during Fruit Development: Insights into Xylem Anatomy and Function Using Microtomography. PLANT PHYSIOLOGY 2015; 168:1590-602. [PMID: 26077763 PMCID: PMC4528730 DOI: 10.1104/pp.15.00031] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Accepted: 06/12/2015] [Indexed: 05/19/2023]
Abstract
Xylem flow of water into fruits declines during fruit development, and the literature indicates a corresponding increase in hydraulic resistance in the pedicel. However, it is unknown how pedicel hydraulics change developmentally in relation to xylem anatomy and function. In this study on grape (Vitis vinifera), we determined pedicel hydraulic conductivity (kh) from pressure-flow relationships using hydrostatic and osmotic forces and investigated xylem anatomy and function using fluorescent light microscopy and x-ray computed microtomography. Hydrostatic kh (xylem pathway) was consistently 4 orders of magnitude greater than osmotic kh (intracellular pathway), but both declined before veraison by approximately 40% and substantially over fruit development. Hydrostatic kh declined most gradually for low (less than 0.08 MPa) pressures and for water inflow and outflow conditions. Specific kh (per xylem area) decreased in a similar fashion to kh despite substantial increases in xylem area. X-ray computed microtomography images provided direct evidence that losses in pedicel kh were associated with blockages in vessel elements, whereas air embolisms were negligible. However, vessel elements were interconnected and some remained continuous postveraison, suggesting that across the grape pedicel, a xylem pathway of reduced kh remains functional late into berry ripening.
Collapse
Affiliation(s)
- Thorsten Knipfer
- Department of Viticulture and Enology (T.K., J.F., G.A.G., A.J.M., M.A.M.) and Department of Plant Sciences/Pomology (K.A.S.), University of California, Davis, California 95616; andUnited States Department of Agriculture-Agricultural Research Service, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Jiong Fei
- Department of Viticulture and Enology (T.K., J.F., G.A.G., A.J.M., M.A.M.) and Department of Plant Sciences/Pomology (K.A.S.), University of California, Davis, California 95616; andUnited States Department of Agriculture-Agricultural Research Service, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Gregory A Gambetta
- Department of Viticulture and Enology (T.K., J.F., G.A.G., A.J.M., M.A.M.) and Department of Plant Sciences/Pomology (K.A.S.), University of California, Davis, California 95616; andUnited States Department of Agriculture-Agricultural Research Service, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Andrew J McElrone
- Department of Viticulture and Enology (T.K., J.F., G.A.G., A.J.M., M.A.M.) and Department of Plant Sciences/Pomology (K.A.S.), University of California, Davis, California 95616; andUnited States Department of Agriculture-Agricultural Research Service, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Kenneth A Shackel
- Department of Viticulture and Enology (T.K., J.F., G.A.G., A.J.M., M.A.M.) and Department of Plant Sciences/Pomology (K.A.S.), University of California, Davis, California 95616; andUnited States Department of Agriculture-Agricultural Research Service, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| | - Mark A Matthews
- Department of Viticulture and Enology (T.K., J.F., G.A.G., A.J.M., M.A.M.) and Department of Plant Sciences/Pomology (K.A.S.), University of California, Davis, California 95616; andUnited States Department of Agriculture-Agricultural Research Service, Crops Pathology and Genetics Research Unit, Davis, California 95616 (A.J.M.)
| |
Collapse
|