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Sabella E, Buja I, Negro C, Vergine M, Cherubini P, Pavan S, Maruccio G, De Bellis L, Luvisi A. The Significance of Xylem Structure and Its Chemical Components in Certain Olive Tree Genotypes with Tolerance to Xylella fastidiosa Infection. PLANTS (BASEL, SWITZERLAND) 2024; 13:930. [PMID: 38611461 PMCID: PMC11013585 DOI: 10.3390/plants13070930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 04/14/2024]
Abstract
Olive quick decline syndrome (OQDS) is a devastating plant disease caused by the bacterium Xylella fastidiosa (Xf). Exploratory missions in the Salento area led to the identification of putatively Xf-resistant olive trees (putatively resistant plants, PRPs) which were pauci-symptomatic or asymptomatic infected plants belonging to different genetic clusters in orchards severely affected by OQDS. To investigate the defense strategies employed by these PRPs to contrast Xf infection, the PRPs were analyzed for the anatomy and histology of xylem vessels, patterns of Xf distribution in host tissues (by the fluorescent in situ hybridization technique-FISH) and the presence of secondary metabolites in stems. The xylem vessels of the PRPs have an average diameter significantly lower than that of susceptible plants for each annual tree ring studied. The histochemical staining of xylem vessels highlighted an increase in the lignin in the parenchyma cells of the medullary rays of the wood. The 3D images obtained from FISH-LSM (laser scanning microscope) revealed that, in the PRPs, Xf cells mostly appeared as individual cells or as small aggregates; in addition, these bacterial cells looked to be incorporated in the autofluorescence signal of gels and phenolic compounds regardless of hosts' genotypes. In fact, the metabolomic data from asymptomatic PRP stems showed a significant increase in compounds like salicylic acid, known as a signal molecule which mediates host responses upon pathogen infection, and luteolin, a naturally derived flavonoid compound with antibacterial properties and with well-known anti-biofilm effects. Findings indicate that the xylem vessel geometry together with structural and chemical defenses are among the mechanisms operating to control Xf infection and may represent a common resistance trait among different olive genotypes.
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Affiliation(s)
- Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Monteroni 165, 73100 Lecce, Italy; (E.S.); (I.B.); (C.N.); (L.D.B.); (A.L.)
- National Biodiversity Future Center, 90133 Palermo, Italy
| | - Ilaria Buja
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Monteroni 165, 73100 Lecce, Italy; (E.S.); (I.B.); (C.N.); (L.D.B.); (A.L.)
| | - Carmine Negro
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Monteroni 165, 73100 Lecce, Italy; (E.S.); (I.B.); (C.N.); (L.D.B.); (A.L.)
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Monteroni 165, 73100 Lecce, Italy; (E.S.); (I.B.); (C.N.); (L.D.B.); (A.L.)
| | - Paolo Cherubini
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Stefano Pavan
- Department of Soil, Plant and Food Science, University of Bari “Aldo Moro”, 70126 Bari, Italy;
| | - Giuseppe Maruccio
- Omnics Research Group, Department of Mathematics and Physics, University of Salento, CNR-Institute of Nanotechnology, INFN Sezione di Lecce, Via per Monteroni, 73100 Lecce, Italy;
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Monteroni 165, 73100 Lecce, Italy; (E.S.); (I.B.); (C.N.); (L.D.B.); (A.L.)
- National Biodiversity Future Center, 90133 Palermo, Italy
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Monteroni 165, 73100 Lecce, Italy; (E.S.); (I.B.); (C.N.); (L.D.B.); (A.L.)
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2
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Walker NC, White SM, Ruiz SA, McKay Fletcher D, Saponari M, Roose T. A mathematical model of biofilm growth and spread within plant xylem: Case study of Xylella fastidiosa in olive trees. J Theor Biol 2024; 581:111737. [PMID: 38280544 DOI: 10.1016/j.jtbi.2024.111737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 11/16/2023] [Accepted: 01/10/2024] [Indexed: 01/29/2024]
Abstract
Xylem-limited bacterial pathogens cause some of the most destructive plant diseases. Though imposed measures to control these pathogens are generally ineffective, even among susceptible taxa, some hosts can limit bacterial loads and symptom expression. Mechanisms by which this resistance is achieved are poorly understood. In particular, it is still unknown how differences in vascular structure may influence biofilm growth and spread within a host. To address this, we developed a novel theoretical framework to describe biofilm behaviour within xylem vessels, adopting a polymer-based modelling approach. We then parameterised the model to investigate the relevance of xylem vessel diameters on Xylella fastidiosa resistance among olive cultivars. The functionality of all vessels was severely reduced under infection, with hydraulic flow reductions of 2-3 orders of magnitude. However, results suggest wider vessels act as biofilm incubators; allowing biofilms to develop over a long time while still transporting them through the vasculature. By contrast, thinner vessels become blocked much earlier, limiting biofilm spread. Using experimental data on vessel diameter distributions, we were able to determine that a mechanism of resistance in the olive cultivar Leccino is a relatively low abundance of the widest vessels, limiting X. fastidiosa spread.
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Affiliation(s)
- N C Walker
- Bioengineering Sciences Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, SO17 1BJ, UK
| | - S M White
- UK Centre for Ecology & Hydrology, Maclean Building, Benson Lane, Crowmarsh Gifford, Wallingford, Oxfordshire OX10 8BB, UK
| | - S A Ruiz
- Bioengineering Sciences Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, SO17 1BJ, UK
| | - D McKay Fletcher
- Bioengineering Sciences Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, SO17 1BJ, UK; Rural Economy Environment and Society Research Group, SRUC, Edinburgh EH9 3JG, UK
| | - M Saponari
- Istituto per la Protezione Sostenibile delle Piante, CNR, Bari, Italy
| | - T Roose
- Bioengineering Sciences Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, SO17 1BJ, UK.
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Verdonk JC, van Ieperen W, Carvalho DRA, van Geest G, Schouten RE. Effect of preharvest conditions on cut-flower quality. FRONTIERS IN PLANT SCIENCE 2023; 14:1281456. [PMID: 38023857 PMCID: PMC10667726 DOI: 10.3389/fpls.2023.1281456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023]
Abstract
The cut flower industry has a global reach as flowers are often produced in countries around the equator and transported by plane or ship (reefer) mostly to the global north. Vase-life issues are often regarded as linked to only postharvest conditions while cultivation factors are just as important. Here, we review the main causes for quality reduction in cut flowers with the emphasis on the importance of preharvest conditions. Cut flower quality is characterised by a wide range of features, such as flower number, size, shape, colour (patterns), fragrance, uniformity of blooming, leaf and stem colour, plant shape and developmental stage, and absence of pests and diseases. Postharvest performance involves improving and preserving most of these characteristics for as long as possible. The main causes for cut flower quality loss are reduced water balance or carbohydrate availability, senescence and pest and diseases. Although there is a clear role for genotype, cultivation conditions are just as important to improve vase life. The role of growth conditions has been shown to be essential; irrigation, air humidity, and light quantity and quality can be used to increase quality. For example, xylem architecture is affected by the irrigation scheme, and the relative humidity in the greenhouse affects stomatal function. Both features determine the water balance of the flowering stem. Light quality and period drives photosynthesis, which is directly responsible for accumulation of carbohydrates. The carbohydrate status is important for respiration, and many senescence related processes. High carbohydrates can lead to sugar loss into the vase water, leading to bacterial growth and potential xylem blockage. Finally, inferior hygiene during cultivation and temperature and humidity control during postharvest can lead to pathogen contamination. At the end of the review, we will discuss the future outlook focussing on new phenotyping tools necessary to quantify the complex interactions between cultivation factors and postharvest performance of cut flowers.
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Affiliation(s)
- Julian C. Verdonk
- Department of Horticulture and Product Physiology, Wageningen University and Research, Wageningen, Netherlands
| | - Wim van Ieperen
- Department of Horticulture and Product Physiology, Wageningen University and Research, Wageningen, Netherlands
| | | | - Geert van Geest
- Interfaculty Bioinformatics, Institut für Biologie, Fakultät für Naturwissenschaften und Naturwissenschaften, Universität Bern, Bern, Switzerland
| | - Rob E. Schouten
- Wageningen Food & Biobased Research, Wageningen University and Research, Wageningen, Netherlands
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Carluccio G, Greco D, Sabella E, Vergine M, De Bellis L, Luvisi A. Xylem Embolism and Pathogens: Can the Vessel Anatomy of Woody Plants Contribute to X. fastidiosa Resistance? Pathogens 2023; 12:825. [PMID: 37375515 DOI: 10.3390/pathogens12060825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/07/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
The maintenance of an intact water column in the xylem lumen several meters above the ground is essential for woody plant viability. In fact, abiotic and biotic factors can lead to the formation of emboli in the xylem, interrupting sap flow and causing consequences on the health status of the plant. Anyway, the tendency of plants to develop emboli depends on the intrinsic features of the xylem, while the cyto-histological structure of the xylem plays a role in resistance to vascular pathogens, as in the case of the pathogenic bacterium Xylella fastidiosa. Analysis of the scientific literature suggests that on grapevine and olive, some xylem features can determine plant tolerance to vascular pathogens. However, the same trend was not reported in citrus, indicating that X. fastidiosa interactions with host plants differ by species. Unfortunately, studies in this area are still limited, with few explaining inter-cultivar insights. Thus, in a global context seriously threatened by X. fastidiosa, a deeper understanding of the relationship between the physical and mechanical characteristics of the xylem and resistance to stresses can be useful for selecting cultivars that may be more resistant to environmental changes, such as drought and vascular pathogens, as a way to preserve agricultural productions and ecosystems.
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Affiliation(s)
- Giambattista Carluccio
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Davide Greco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy
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5
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Zhang Z, Long Y, Yin X, Yang S. Sulfur-Induced Resistance against Pseudomonas syringae pv. actinidiae via Triggering Salicylic Acid Signaling Pathway in Kiwifruit. Int J Mol Sci 2021; 22:ijms222312710. [PMID: 34884527 PMCID: PMC8657834 DOI: 10.3390/ijms222312710] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/13/2021] [Accepted: 11/15/2021] [Indexed: 11/21/2022] Open
Abstract
Sulfur has been previously reported to modulate plant growth and exhibit significant anti-microbial activities. However, the mechanism underlying its diverse effects on plant pathogens has not been elucidated completely. The present study conducted the two-year field experiment of sulfur application to control kiwifruit canker from 2017 to 2018. For the first time, our study uncovered activation of plant disease resistance by salicylic acid after sulfur application in kiwifruit. The results indicated that when the sulfur concentration was 1.5–2.0 kg m−3, the induced effect of kiwifruit canker reached more than 70%. Meanwhile, a salicylic acid high lever was accompanied by the decline of jasmonic acid. Further analysis revealed the high expression of the defense gene, especially AcPR-1, which is a marker of the salicylic acid signaling pathway. Additionally, AcICS1, another critical gene of salicylic acid synthesis, was also highly expressed. All contributed to the synthesis of increasing salicylic acid content in kiwifruit leaves. Moreover, the first key lignin biosynthetic AcPAL gene was marked up-regulated. Thereafter, accumulation of lignin content in the kiwifruit stem and the higher deposition of lignin were visible in histochemical analysis. Moreover, the activity of the endochitinase activity of kiwifruit leaves increased significantly. We suggest that the sulfur-induced resistance against Pseudomonas syringae pv. actinidiae via salicylic activates systemic acquired resistance to enhance plant immune response in kiwifruit.
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Affiliation(s)
- Zhuzhu Zhang
- College of Agriculture, Guizhou University, Guiyang 550025, China;
| | - Youhua Long
- College of Agriculture, Guizhou University, Guiyang 550025, China;
- Correspondence: (Y.L.); (X.Y.)
| | - Xianhui Yin
- College of Agriculture, Guizhou University, Guiyang 550025, China;
- Correspondence: (Y.L.); (X.Y.)
| | - Sen Yang
- Kiwifruit Engineering & Technology Research Center, Guizhou University, Guiyang 550025, China;
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Ramsing CK, Gramaje D, Mocholí S, Agustí J, Cabello Sáenz de Santa María F, Armengol J, Berbegal M. Relationship Between the Xylem Anatomy of Grapevine Rootstocks and Their Susceptibility to Phaeoacremonium minimum and Phaeomoniella chlamydospora. FRONTIERS IN PLANT SCIENCE 2021; 12:726461. [PMID: 34712253 PMCID: PMC8546399 DOI: 10.3389/fpls.2021.726461] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
Fungal grapevine trunk diseases (GTDs) are some of the most pressing threats to grape production worldwide. While these diseases are associated with several fungal pathogens, Phaeomoniella chlamydospora and Phaeoacremonium minimum are important contributors to esca and Petri diseases. Recent research has linked grapevine xylem diameter with tolerance to Pa. chlamydospora in commercial rootstocks. In this study, we screen over 25 rootstocks for xylem characteristics and tolerance to both Pa. chlamydospora and Pm. minimum. Tolerance was measured by fungal incidence and DNA concentration (quantified via qPCR), while histological analyses were used to measure xylem characteristics, including xylem vessels diameter, density, and the proportion of the stem surface area covered by xylem vessels. Rootstocks were grouped into different classes based on xylem characteristics to assess the potential association between vasculature traits and pathogen tolerance. Our results revealed significant differences in all the analyzed xylem traits, and also in DNA concentration for both pathogens among the tested rootstocks. They corroborate the link between xylem vessels diameter and tolerance to Pa. chlamydospora. In Pm. minimum, the rootstocks with the widest xylem diameter proved the most susceptible. This relationship between vasculature development and pathogen tolerance has the potential to inform both cultivar choice and future rootstock breeding to reduce the detrimental impact of GTDs worldwide.
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Affiliation(s)
- Charis K. Ramsing
- Instituto Agroforestal Mediterráneo, Universitat Politècnica de València, Valencia, Spain
| | - David Gramaje
- Instituto de Ciencias de la Vid y del Vino (ICVV), Consejo Superior de Investigaciones Científicas, Universidad de la Rioja–Gobierno de La Rioja, Logroño, Spain
| | - Sara Mocholí
- Instituto Agroforestal Mediterráneo, Universitat Politècnica de València, Valencia, Spain
| | - Javier Agustí
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas (CSIC) Universitat Politècnica de València, Valencia, Spain
| | | | - Josep Armengol
- Instituto Agroforestal Mediterráneo, Universitat Politècnica de València, Valencia, Spain
| | - Mónica Berbegal
- Instituto Agroforestal Mediterráneo, Universitat Politècnica de València, Valencia, Spain
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7
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Ren H, Wu Y, Ahmed T, Qi X, Li B. Response of Resistant and Susceptible Bayberry Cultivars to Infection of Twig Blight Pathogen by Histological Observation and Gibberellin Related Genes Expression. Pathogens 2021; 10:402. [PMID: 33805451 PMCID: PMC8066835 DOI: 10.3390/pathogens10040402] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/22/2021] [Accepted: 03/22/2021] [Indexed: 11/16/2022] Open
Abstract
Bayberry is an important fruit tree native to the subtropical regions of China. However, a systematic twig blight disease caused by Pestalotiopsis versicolor and P. microspora, resulted in the death of the whole tree of bayberry. The main variety Dongkui is highly sensitive to the twig blight disease, but the variety Zaojia is very highly resistant to the disease. Therefore, it is very necessary to clear the difference between resistant and susceptible varieties in response to the fungal infection. In this paper, we investigated the response of resistant and susceptible bayberry cultivars to infection of twig blight pathogen by histological observation and gibberellin signaling pathway-related genes expression. Microscopic observation revealed the difference in the infection process between resistant and susceptible varieties. The results of frozen scanning electron microscopy showed that the Pestalotiopsis conidia were shrunk, the mycelium was shriveled and did not extend into the cells of resistant cultivars, while the conidia were full and the top was extended, the mycelia was normal and continued to extend to the cells of a susceptible cultivar. Indeed, the medulla cells were almost intact in resistant cultivar, but obviously damaged in susceptible cultivar after inoculation of the main fungal pathogen P. versicolor conidia, which is earlier germinated on sterile glass slide than that of a hard plastic slide. The quantitative real-time PCR results showed a significant difference between resistant and susceptible cultivars in the expression of gibberellin signaling pathway-related genes in leaves and stems of bayberry, which is closely related to infection time, the type of genes and varieties. Overall, this study provides a clue for our understanding of the resistance mechanism of bayberry against the twig blight disease.
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Affiliation(s)
- Haiying Ren
- The Institute of Horticulture Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (H.R.); (X.Q.)
| | - Yangchun Wu
- College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, China;
| | - Temoor Ahmed
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China;
| | - Xingjiang Qi
- The Institute of Horticulture Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (H.R.); (X.Q.)
| | - Bin Li
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China;
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Pouzoulet J, Rolshausen PE, Charbois R, Chen J, Guillaumie S, Ollat N, Gambetta GA, Delmas CEL. Behind the curtain of the compartmentalization process: Exploring how xylem vessel diameter impacts vascular pathogen resistance. PLANT, CELL & ENVIRONMENT 2020; 43:2782-2796. [PMID: 32681569 DOI: 10.1111/pce.13848] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/07/2020] [Accepted: 07/10/2020] [Indexed: 05/07/2023]
Abstract
A key determinant of plant resistance to vascular infections lies in the ability of the host to successfully compartmentalize invaders at the xylem level. Growing evidence supports that the structural properties of the vascular system impact host vulnerability towards vascular pathogens. The aim of this study was to provide further insight into the impact of xylem vessel diameter on compartmentalization efficiency and thus vascular pathogen movement, using the interaction between Vitis and Phaeomoniella chlamydospora as a model system. We showed experimentally that an increased number of xylem vessels above 100 μm of diameter resulted in a higher mean infection level of host tissue. This benchmark was validated within and across Vitis genotypes. Although the ability of genotypes to restore vascular cambium integrity upon infection was highly variable, this trait did not correlate with their ability to impede pathogen movement at the xylem level. The distribution of infection severity of cuttings across the range of genotype's susceptibility suggests that a risk-based mechanism is involved. We used this experimental data to calibrate a mechanistic stochastic model of the pathogen spread and we provide evidence that the efficiency of the compartmentalization process within a given xylem vessel is a function of its diameter.
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Affiliation(s)
- Jérôme Pouzoulet
- EGFV, INRAE, Bordeaux-Sciences Agro, Université Bordeaux, ISVV, Villenave d'Ornon, France
| | - Philippe E Rolshausen
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA
| | - Rémi Charbois
- EGFV, INRAE, Bordeaux-Sciences Agro, Université Bordeaux, ISVV, Villenave d'Ornon, France
| | - Jinliang Chen
- EGFV, INRAE, Bordeaux-Sciences Agro, Université Bordeaux, ISVV, Villenave d'Ornon, France
| | - Sabine Guillaumie
- EGFV, INRAE, Bordeaux-Sciences Agro, Université Bordeaux, ISVV, Villenave d'Ornon, France
| | - Nathalie Ollat
- EGFV, INRAE, Bordeaux-Sciences Agro, Université Bordeaux, ISVV, Villenave d'Ornon, France
| | - Gregory A Gambetta
- EGFV, INRAE, Bordeaux-Sciences Agro, Université Bordeaux, ISVV, Villenave d'Ornon, France
| | - Chloé E L Delmas
- SAVE, INRAE, Bordeaux-Sciences Agro, ISVV, Villenave d'Ornon, France
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Sabella E, Moretti S, Gärtner H, Luvisi A, De Bellis L, Vergine M, Saurer M, Cherubini P. Increase in ring width, vessel number and δ18O in olive trees infected with Xylella fastidiosa. TREE PHYSIOLOGY 2020; 40:1583-1594. [PMID: 32705131 DOI: 10.1093/treephys/tpaa095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
Xylella fastidiosa (Xf) Wells, Raju et al., 1986 is a bacterium that causes plant diseases in the Americas. In Europe, it was first detected on the Salento Peninsula (Italy), where it was found to be associated with the olive quick decline syndrome. Here, we present the results of the first tree-ring study of infected and uninfected olive trees (Olea europaea L.) of two different cultivars, one resistant and one susceptible, to establish the effects induced by the spread of the pathogen inside the tree. Changes in wood anatomical characteristics, such as an increase in the number of vessels and in ring width, were observed in the infected plants of both the cultivars Cellina di Nardò (susceptible to Xf infection) and Leccino (resistant to Xf infection). Thus, whether infection affects the mortality of the tree or not, the tree shows a reaction to it. The presence of occlusions was detected in the wood of both 4-year-old branches and the tree stem core. As expected, the percentage of occluded vessels in the Xf-susceptible cultivar Cellina di Nardò was significantly higher than in the Xf-resistant cultivar Leccino. The δ 18O of the 4-year-old branches was significantly higher in infected trees of both cultivars than in noninfected trees, while no variations in δ 13C were observed. This suggests a reduction in leaf transpiration rates during infection and seems to be related to the occlusions observed in rings of the 4-year-old branches. Such occlusions can determine effects at leaf level that could influence stomatal activity. On the other hand, the significant increase in the number of vessels in infected trees could be related to the tree's attempt to enhance water conductivity in response to the pathogen-induced vessel occlusions.
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Affiliation(s)
- Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Samuele Moretti
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Laboratoire Vigne, Biotechnologies et Environnement (LVBE, EA 3991), Université de Haute-Alsace, 33 rue de Herrlisheim, 68008 Colmar Cedex, France
| | - Holger Gärtner
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, Lecce, 73100, Italy
| | - Matthias Saurer
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
| | - Paolo Cherubini
- WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
- Department of Forest and Conservation Sciences, University of British Columbia, 3041 - 2424 Main Mall, Vancouver, BC, Canada
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10
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Sabella E, Aprile A, Genga A, Siciliano T, Nutricati E, Nicolì F, Vergine M, Negro C, De Bellis L, Luvisi A. Xylem cavitation susceptibility and refilling mechanisms in olive trees infected by Xylella fastidiosa. Sci Rep 2019; 9:9602. [PMID: 31270378 PMCID: PMC6610111 DOI: 10.1038/s41598-019-46092-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 06/19/2019] [Indexed: 01/09/2023] Open
Abstract
In olive trees, Xylella fastidiosa colonizes xylem vessels and compromises water transport causing the olive quick decline syndrome (OQDS). The loss of hydraulic conductivity could be attributed to vessel occlusions induced both by the bacteria biofilm and by plant responses (tyloses, gums, etc.) that could trigger embolism. The ability of the infected plants to detect embolism and to respond, by activating mechanisms to restore the hydraulic conductivity, can influence the severity of the disease symptomatology. In order to investigate these mechanisms in the X. fastidiosa-resistant olive cultivar Leccino and in the susceptible Cellina di Nardò, sections of healthy olive stems were analysed by laser scanning microscope to calculate the cavitation vulnerability index. Findings indicated that the cultivar Leccino seems to be constitutively less susceptible to cavitation than the susceptible one. Among the vascular refilling mechanisms, starch hydrolysis is a well-known strategy to refill xylem vessels that suffered cavitation and it is characterized by a dense accumulation of starch grains in the xylem parenchima; SEM-EDX analysis of stem cross-sections of infected plants revealed an aggregation of starch grains in the Leccino xylem vessels. These observations could indicate that this cultivar, as well as being anatomically less susceptible to cavitation, it also could be able to activate more efficient refilling mechanisms, restoring vessel's hydraulic conductivity. In order to verify this hypothesis, we analysed the expression levels of some genes belonging to families involved in embolism sensing and refilling mechanisms: aquaporins, sucrose transporters, carbohydrate metabolism and enzymes related to starch breakdown, alpha and beta-amylase. The obtained genes expression patterns suggested that the infected plants of the cultivar Leccino strongly modulates the genes involved in embolism sensing and refilling.
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Affiliation(s)
- Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Alessio Aprile
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy.
| | - Alessandra Genga
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Tiziana Siciliano
- Department of Physic and Math, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Eliana Nutricati
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Francesca Nicolì
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Carmine Negro
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100, Lecce, Italy
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11
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Munitz S, Netzer Y, Shtein I, Schwartz A. Water availability dynamics have long-term effects on mature stem structure in Vitis vinifera. AMERICAN JOURNAL OF BOTANY 2018; 105:1443-1452. [PMID: 30168862 DOI: 10.1002/ajb2.1148] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 05/25/2018] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY The stem of Vitis vinifera, a climbing vine of global economic importance, is characterized by both wide and narrow vessels and high specific hydraulic conductivity. While the effect of drought stress has been studied in 1- and 2-yr-old stems, there are few data documenting effects of drought stress on the anatomical structure of the mature, woody stem near the base of the vine. Here we describe mature wood anatomical responses to two irrigation regimes on wood anatomy and specific hydraulic conductivity in Vitis vinifera Merlot vines. METHODS For 4 years, irrigation was applied constantly at low, medium, or high levels, or at alternating levels at two different periods during the growing season, either early spring or late summer, resulting in late season or early spring deficits, respectively. The following variables were measured: trunk diameter, annual ring width and area, vessel diameter, specific hydraulic conductivity and stem water potential. KEY RESULTS High water availability early in the season (late deficit) resulted in vigorous vegetative growth (greater trunk diameter, ring width and area), wider vessels and increased specific hydraulic conductivity. High water availability early in the season caused a shift of the vessel population towards the wider frequency classes. These late deficit vines showed more negative water potential values late in the season than vines that received low but relatively constant irrigation. CONCLUSIONS We concluded that high water availability during vegetative growth period of Vitis increases vessels diameter and hydraulic conductivity and causes the vines to be more vulnerable to drought stress late in the season.
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Affiliation(s)
- Sarel Munitz
- R.H. Smith Institute of Plant Science and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
- The Eastern Regional Research and Development Center, Ariel, 40700, Israel
| | - Yishai Netzer
- R.H. Smith Institute of Plant Science and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
- The Eastern Regional Research and Development Center, Ariel, 40700, Israel
- Biotech engineering department, Ariel University, Ariel, 40700, Israel
| | - Ilana Shtein
- R.H. Smith Institute of Plant Science and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
- The Eastern Regional Research and Development Center, Ariel, 40700, Israel
| | - Amnon Schwartz
- R.H. Smith Institute of Plant Science and Genetics in Agriculture, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
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12
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Sabella E, Luvisi A, Aprile A, Negro C, Vergine M, Nicolì F, Miceli A, De Bellis L. Xylella fastidiosa induces differential expression of lignification related-genes and lignin accumulation in tolerant olive trees cv. Leccino. JOURNAL OF PLANT PHYSIOLOGY 2018; 220:60-68. [PMID: 29149645 DOI: 10.1016/j.jplph.2017.10.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 10/25/2017] [Accepted: 10/27/2017] [Indexed: 05/04/2023]
Abstract
Recently, Xylella fastidiosa was reported in Italy, associated with the "Olive Quick Decline Syndrome". The cv. Leccino exhibits an evident tolerance with a slow disease progression compared with the other cultivars. Between the mechanisms proposed to explain the putative tolerance of some hosts to X. fastidiosa diseases, lignin deposition plays an important role. Analysis of phenolic compounds in healthy and infected Leccino and Cellina di Nardò leaves showed, in the two cultivars, a reduction of hydroxytyrosol glucoside (usually associated with drought and cold stress) and, only in Leccino, an increase of quinic acid, precursor of lignin. To determine if lignin biosynthesis is involved in defence response, we investigated the expression of genes coding for entry-point enzymes in different branches of the phenylpropanoid pathway. In stems of Cellina di Nardò infected plants, Cinnamate-4-Hydroxylase (C4H) and 4-Coumarate:CoA Ligase (4CL) resulted strongly down-regulated, indicating a plant disease response since the inhibition of C4H is reported to promote the accumulation of benzoic acid and salicylic acid as defence signals. Instead, in the cv. Leccino, Cinnamoyl-CoA Reductase (CCR, reported to be strongly induced during the formation of lignin defence response associated) was up-regulated in the stem of infected plants; moreover, Polyphenol oxidase (PPO), coding for an enzyme involved in the hydroxytyrosol biosynthesis, was down-regulated. The quantification of lignin in healthy and infected branches of both cultivars, showed a significant increase of total lignin in infected Leccino compared with the sensitive cultivar; moreover, histochemical observations of stem sections exhibited a different lignin distribution in the sclerenchyma and in the xylem tissue of infected Leccino plants compared to sections of healthy ones. Results suggest a critical role for lignin in X. fastidiosa tolerance of cv. Leccino.
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Affiliation(s)
- Erika Sabella
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy.
| | - Alessio Aprile
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy
| | - Carmine Negro
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy
| | - Marzia Vergine
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy
| | - Francesca Nicolì
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy
| | - Antonio Miceli
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies, University of Salento, via Prov.le Monteroni 165, 73100 Lecce, Italy
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13
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Hao L, Johnson K, Cursino L, Mowery P, Burr TJ. Characterization of the Xylella fastidiosa PD1311 gene mutant and its suppression of Pierce's disease on grapevines. MOLECULAR PLANT PATHOLOGY 2017; 18:684-694. [PMID: 27388152 PMCID: PMC6638296 DOI: 10.1111/mpp.12428] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 04/17/2016] [Accepted: 05/13/2016] [Indexed: 05/25/2023]
Abstract
Xylella fastidiosa causes Pierce's disease (PD) on grapevines, leading to significant economic losses in grape and wine production. To further our understanding of X. fastidiosa virulence on grapevines, we examined the PD1311 gene, which encodes a putative acyl-coenzyme A (acyl-CoA) synthetase, and is highly conserved across Xylella species. It was determined that PD1311 is required for virulence, as the deletion mutant, ΔPD1311, was unable to cause disease on grapevines. The ΔPD1311 strain was impaired in behaviours known to be associated with PD development, including motility, aggregation and biofilm formation. ΔPD1311 also expressed enhanced sensitivity to H2 O2 and polymyxin B, and showed reduced survival in grapevine sap, when compared with wild-type X. fastidiosa Temecula 1 (TM1). Following inoculation, ΔPD1311 could not be detected in grape shoots, which may be related to its altered growth and sensitivity phenotypes. Inoculation with ΔPD1311 2 weeks prior to TM1 prevented the development of PD in a significant fraction of vines and eliminated detectable levels of TM1. In contrast, vines inoculated simultaneously with TM1 and ΔPD1311 developed disease at the same level as TM1 alone. In these vines, TM1 populations were distributed similarly to populations in TM1-only inoculated plants. These findings suggest that, through an indirect mechanism, pretreatment of vines with ΔPD1311 suppresses pathogen population and disease.
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Affiliation(s)
- Lingyun Hao
- Department of Plant Pathology and Plant–Microbe BiologyCornell University‐New York State Agricultural Experiment StationGenevaNY14456USA
| | - Kameka Johnson
- Department of Plant Pathology and Plant–Microbe BiologyCornell University‐New York State Agricultural Experiment StationGenevaNY14456USA
| | - Luciana Cursino
- Department of BiologyHobart and William Smith CollegesGenevaNY14456USA
- Present address:
Division of Natural SciencesKeuka CollegeKeuka ParkNY14478USA
| | - Patricia Mowery
- Department of BiologyHobart and William Smith CollegesGenevaNY14456USA
| | - Thomas J. Burr
- Department of Plant Pathology and Plant–Microbe BiologyCornell University‐New York State Agricultural Experiment StationGenevaNY14456USA
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14
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Nardini A, Savi T, Losso A, Petit G, Pacilè S, Tromba G, Mayr S, Trifilò P, Lo Gullo MA, Salleo S. X-ray microtomography observations of xylem embolism in stems of Laurus nobilis are consistent with hydraulic measurements of percentage loss of conductance. THE NEW PHYTOLOGIST 2017; 213:1068-1075. [PMID: 27735069 DOI: 10.1111/nph.14245] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 09/02/2016] [Indexed: 06/06/2023]
Abstract
Drought-induced xylem embolism is a serious threat to plant survival under future climate scenarios. Hence, accurate quantification of species-specific vulnerability to xylem embolism is a key to predict the impact of climate change on vegetation. Low-cost hydraulic measurements of embolism rate have been suggested to be prone to artefacts, thus requiring validation by direct visualization of the functional status of xylem conduits using nondestructive imaging techniques, such as X-ray microtomography (microCT). We measured the percentage loss of conductance (PLC) of excised stems of Laurus nobilis (laurel) dehydrated to different xylem pressures, and compared results with direct observation of gas-filled vs water-filled conduits at a synchrotron-based microCT facility using a phase contrast imaging modality. Theoretical PLC calculated on the basis of microCT observations in stems of laurel dehydrated to different xylem pressures overall were in agreement with hydraulic measurements, revealing that this species suffers a 50% loss of xylem hydraulic conductance at xylem pressures averaging -3.5 MPa. Our data support the validity of estimates of xylem vulnerability to embolism based on classical hydraulic techniques. We discuss possible causes of discrepancies between data gathered in this study and those of recent independent reports on laurel hydraulics.
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Affiliation(s)
- Andrea Nardini
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| | - Tadeja Savi
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| | - Adriano Losso
- Institut für Botanik, Universität Innsbruck, Sternwarterstrasse 15, A-6020, Innsbruck, Austria
| | - Giai Petit
- Dipartimento Territorio e Sistemi Agro-forestali, Università degli Studi di Padova, Viale dell'Università 16, 35020, Legnaro (PD), Italy
| | - Serena Pacilè
- Dipartimento di Ingegneria e Architettura, Università di Trieste, Piazzale Europa 1, 34127, Trieste, Italy
- Elettra-Sincrotrone Trieste, Area Science Park, 34149, Basovizza, Trieste, Italy
| | - Giuliana Tromba
- Elettra-Sincrotrone Trieste, Area Science Park, 34149, Basovizza, Trieste, Italy
| | - Stefan Mayr
- Institut für Botanik, Universität Innsbruck, Sternwarterstrasse 15, A-6020, Innsbruck, Austria
| | - Patrizia Trifilò
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, Università di Messina, Salita F. Stagno D'Alcontres 31, 98166, Messina, Italy
| | - Maria A Lo Gullo
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche e Ambientali, Università di Messina, Salita F. Stagno D'Alcontres 31, 98166, Messina, Italy
| | - Sebastiano Salleo
- Dipartimento di Scienze della Vita, Università di Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
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15
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Ghasemkhani M, Garkava-Gustavsson L, Liljeroth E, Nybom H. Assessment of diversity and genetic relationships of Neonectria ditissima: the causal agent of fruit tree canker. Hereditas 2016; 153:7. [PMID: 28096769 PMCID: PMC5226109 DOI: 10.1186/s41065-016-0011-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 06/15/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Neonectria ditissima is one of the most important fungal pathogens of apple trees, where it causes fruit tree canker. Information about the amount and partitioning of genetic variation of this fungus could be helpful for improving orchard management strategies and for breeding apple cultivars with high levels of genetically determined resistance. In this study single-spore Neonectria isolates originating from both the same and from different perithecia, apple cultivars and apple orchards in Sweden and Belgium, were evaluated for AFLP- and SSR-based genetic similarity and for mating system. RESULTS Seven SSR loci produced a total of 31 alleles with an average of 4 alleles per locus, while 11 AFLP primer combinations produced an average of 35 fragments per primer combination and 71 % polymorphic fragments. An AFLP-based analysis of molecular variance (AMOVA) revealed that 89 % of the variation was found within orchards and 11 % between orchards. Genetic similarity among the studied isolates was illustrated with a principal coordinate analyseis (PCoA) and a dendrogram. AFLP-based Jaccard's similarity coefficients were the highest when single-ascospore isolates obtained from the same perithecium were compared, medium-high for isolates from different perithecia on the same tree, and lowest when isolates from different trees were compared. CONCLUSIONS Based on the results of PCoA and AMOVA analysis, isolates from the same or geographically close orchards did not group together. Since AFLP profiles differed also when single-ascospore isolates from the same perithecium were compared, the mating system of N. ditissima is most likely heterothallic.
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Affiliation(s)
- Marjan Ghasemkhani
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Box 101, 230 53 Alnarp, Sweden
| | - Larisa Garkava-Gustavsson
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Box 101, 230 53 Alnarp, Sweden
| | - Erland Liljeroth
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, 230 53 Alnarp, Sweden
| | - Hilde Nybom
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Balsgård, Fjälkestadsvägen 459, 29194 Kristianstad, Sweden
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16
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Hochberg U, Herrera JC, Cochard H, Badel E. Short-time xylem relaxation results in reliable quantification of embolism in grapevine petioles and sheds new light on their hydraulic strategy. TREE PHYSIOLOGY 2016; 36:748-55. [PMID: 26843208 DOI: 10.1093/treephys/tpv145] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 12/21/2015] [Indexed: 05/21/2023]
Abstract
In recent years, the validity of embolism quantification methods has been questioned, especially for long-vesseled plants. Some studies have suggested that cutting xylem while under tension, even under water, might generate artificial cavitation. Accordingly, a rehydration procedure prior to hydraulic measurements has been recommended to avoid this artefact. On the other hand, concerns have been raised that xylem refilling might occur when samples are rehydrated. Here, we explore the potential biases affecting embolism quantification for grapevine (Vitis vinifera L.) petioles harvested under tension or after xylem relaxation. We employ direct visualization of embolism through X-ray micro-computed tomography (microCT) to test for the occurrence of fast refilling (artifactually low per cent loss of conductivity (PLC) due to rehydration prior to sample harvest) as well as excision-induced embolism (artifactually high embolism due to air introduction during harvest). Additionally, we compared the response functions of both stomatal regulation and xylem embolism to xylem pressure (Ψx). Short-time (20 min) xylem tension relaxation prior to the hydraulic measurement resulted in a lower degree of embolism than found in samples harvested under native tensions, and yielded xylem vulnerability curves similar to the ones obtained using direct microCT visualization. Much longer periods of hydration (overnight) were required before xylem refilling was observed to occur. In field-grown vines, over 85% of stomatal closure occurred at less negative Ψx than that required to induce 12% PLC. Our results demonstrate that relaxation of xylem tension prior to hydraulic measurement allows for the reliable quantification of native embolism in grapevine petioles. Furthermore, we find that stomatal regulation is sufficiently conservative to avoid transpiration-induced cavitation. These results suggest that grapevines have evolved a strategy of cavitation resistance, rather than one of cavitation tolerance (diurnal cycles of embolism and repair).
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Affiliation(s)
- Uri Hochberg
- Department of Agricultural and Environmental Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy INRA, UMR 547 PIAF, 63100 Clermont-Ferrand, France Clermont Université, Université Blaise-Pascal, UMR 547 PIAF, 63000 Clermont-Ferrand, France
| | - Jose Carlos Herrera
- Department of Agricultural and Environmental Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy
| | - Hervé Cochard
- INRA, UMR 547 PIAF, 63100 Clermont-Ferrand, France Clermont Université, Université Blaise-Pascal, UMR 547 PIAF, 63000 Clermont-Ferrand, France
| | - Eric Badel
- INRA, UMR 547 PIAF, 63100 Clermont-Ferrand, France Clermont Université, Université Blaise-Pascal, UMR 547 PIAF, 63000 Clermont-Ferrand, France
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17
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Nascimento R, Gouran H, Chakraborty S, Gillespie HW, Almeida-Souza HO, Tu A, Rao BJ, Feldstein PA, Bruening G, Goulart LR, Dandekar AM. The Type II Secreted Lipase/Esterase LesA is a Key Virulence Factor Required for Xylella fastidiosa Pathogenesis in Grapevines. Sci Rep 2016; 6:18598. [PMID: 26753904 PMCID: PMC4709584 DOI: 10.1038/srep18598] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 11/03/2015] [Indexed: 11/09/2022] Open
Abstract
Pierce's disease (PD) of grapevines is caused by Xylella fastidiosa (Xf), a xylem-limited gamma-proteobacterium that is responsible for several economically important crop diseases. The occlusion of xylem elements and interference with water transport by Xf and its associated biofilm have been posited as the main cause of PD symptom development; however, Xf virulence mechanisms have not been described. Analysis of the Xf secretome revealed a putative lipase/esterase (LesA) that was abundantly secreted in bacterial culture supernatant and was characterized as a protein ortholog of the cell wall-degrading enzyme LipA of Xanthomonas strains. LesA was secreted by Xf and associated with a biofilm filamentous network. Additional proteomic analysis revealed its abundant presence in outer membrane vesicles (OMVs). Accumulation of LesA in leaf regions associated positively with PD symptoms and inversely with bacterial titer. The lipase/esterase also elicited a hypersensitive response in grapevine. Xf lesA mutants were significantly deficient for virulence when mechanically inoculated into grapevines. We propose that Xf pathogenesis is caused by LesA secretion mediated by OMV cargos and that its release and accumulation in leaf margins leads to early stages of observed PD symptoms.
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Affiliation(s)
- Rafael Nascimento
- Plant Sciences Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
- Institute of Genetics and Biochemistry, Federal University of Uberlândia, Av. Amazonas, Bloco 2E, Campus Umuarama, 38400-902, Uberlândia MG, Brazil
| | - Hossein Gouran
- Plant Sciences Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
| | - Sandeep Chakraborty
- Plant Sciences Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
| | - Hyrum W. Gillespie
- Plant Sciences Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
| | - Hebréia O. Almeida-Souza
- Institute of Genetics and Biochemistry, Federal University of Uberlândia, Av. Amazonas, Bloco 2E, Campus Umuarama, 38400-902, Uberlândia MG, Brazil
| | - Aye Tu
- Plant Sciences Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
| | - Basuthkar J. Rao
- Department of Biological Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India
| | - Paul A. Feldstein
- Plant Pathology Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
| | - George Bruening
- Plant Pathology Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
| | - Luiz R. Goulart
- Medical Microbiology and Immunology Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA
- Institute of Genetics and Biochemistry, Federal University of Uberlândia, Av. Amazonas, Bloco 2E, Campus Umuarama, 38400-902, Uberlândia MG, Brazil
| | - Abhaya M. Dandekar
- Plant Sciences Department, University of California, Davis, 1 Shields Ave, Davis CA, 95616, USA.
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18
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Buckley TN, John GP, Scoffoni C, Sack L. How Does Leaf Anatomy Influence Water Transport outside the Xylem? PLANT PHYSIOLOGY 2015; 168:1616-35. [PMID: 26084922 PMCID: PMC4528767 DOI: 10.1104/pp.15.00731] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 06/15/2015] [Indexed: 05/18/2023]
Abstract
Leaves are arguably the most complex and important physicobiological systems in the ecosphere. Yet, water transport outside the leaf xylem remains poorly understood, despite its impacts on stomatal function and photosynthesis. We applied anatomical measurements from 14 diverse species to a novel model of water flow in an areole (the smallest region bounded by minor veins) to predict the impact of anatomical variation across species on outside-xylem hydraulic conductance (Kox). Several predictions verified previous correlational studies: (1) vein length per unit area is the strongest anatomical determinant of Kox, due to effects on hydraulic pathlength and bundle sheath (BS) surface area; (2) palisade mesophyll remains well hydrated in hypostomatous species, which may benefit photosynthesis, (3) BS extensions enhance Kox; and (4) the upper and lower epidermis are hydraulically sequestered from one another despite their proximity. Our findings also provided novel insights: (5) the BS contributes a minority of outside-xylem resistance; (6) vapor transport contributes up to two-thirds of Kox; (7) Kox is strongly enhanced by the proximity of veins to lower epidermis; and (8) Kox is strongly influenced by spongy mesophyll anatomy, decreasing with protoplast size and increasing with airspace fraction and cell wall thickness. Correlations between anatomy and Kox across species sometimes diverged from predicted causal effects, demonstrating the need for integrative models to resolve causation. For example, (9) Kox was enhanced far more in heterobaric species than predicted by their having BS extensions. Our approach provides detailed insights into the role of anatomical variation in leaf function.
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Affiliation(s)
- Thomas N Buckley
- I.A. Watson Grains Research Centre, Faculty of Agriculture and Environment, University of Sydney, Narrabri, New South Wales 2390, Australia (T.N.B.); andDepartment of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095 (G.P.J., C.S., L.S.)
| | - Grace P John
- I.A. Watson Grains Research Centre, Faculty of Agriculture and Environment, University of Sydney, Narrabri, New South Wales 2390, Australia (T.N.B.); andDepartment of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095 (G.P.J., C.S., L.S.)
| | - Christine Scoffoni
- I.A. Watson Grains Research Centre, Faculty of Agriculture and Environment, University of Sydney, Narrabri, New South Wales 2390, Australia (T.N.B.); andDepartment of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095 (G.P.J., C.S., L.S.)
| | - Lawren Sack
- I.A. Watson Grains Research Centre, Faculty of Agriculture and Environment, University of Sydney, Narrabri, New South Wales 2390, Australia (T.N.B.); andDepartment of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095 (G.P.J., C.S., L.S.)
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Lin H, Islam MS, Cabrera-La Rosa JC, Civerolo EL, Groves RL. Population Structure of Xylella fastidiosa Associated with Almond Leaf Scorch Disease in the San Joaquin Valley of California. PHYTOPATHOLOGY 2015; 105:825-32. [PMID: 25807309 DOI: 10.1094/phyto-09-14-0254-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Xylella fastidiosa causes disease in many commercial crops, including almond leaf scorch (ALS) disease in susceptible almond (Prunus dulcis). In this study, genetic diversity and population structure of X. fastidiosa associated with ALS disease were evaluated. Isolates obtained from two almond orchards in Fresno and Kern County in the San Joaquin Valley of California were analyzed for two successive years. Multilocus simple-sequence repeat (SSR) analysis revealed two major genetic clusters that were associated with two host cultivars, 'Sonora' and 'Nonpareil', respectively, regardless of the year of study or location of the orchard. These relationships suggest that host cultivar selection and adaptation are major driving forces shaping ALS X. fastidiosa population structure in the San Joaquin Valley. This finding will provide insight into understanding pathogen adaptation and host selection in the context of ALS disease dynamics.
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Affiliation(s)
- Hong Lin
- First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706
| | - Md Sajedul Islam
- First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706
| | - Juan C Cabrera-La Rosa
- First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706
| | - Edwin L Civerolo
- First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706
| | - Russell L Groves
- First, second, and fourth authors: United States Department of Agriculture-Agricultural Research Service (USDA-ARS) San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757; second author: Department of Viticulture and Enology, University of California, Davis 95616; third author: Universidad Privada Antenor Orrego, Trujillo, Perú; and fifth author: Department of Entomology, University of Wisconsin, Madison 53706
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20
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Scientific Opinion on the risks to plant health posed byXylella fastidiosain the EU territory, with the identification and evaluation of risk reduction options. EFSA J 2015. [DOI: 10.2903/j.efsa.2015.3989] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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21
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Tombesi S, Nardini A, Farinelli D, Palliotti A. Relationships between stomatal behavior, xylem vulnerability to cavitation and leaf water relations in two cultivars of Vitis vinifera. PHYSIOLOGIA PLANTARUM 2014; 152:453-64. [PMID: 24597791 DOI: 10.1111/ppl.12180] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 02/03/2014] [Accepted: 02/03/2014] [Indexed: 05/21/2023]
Abstract
Current understanding of physiological mechanisms governing stomatal behavior under water stress conditions is still incomplete and controversial. It has been proposed that coordination of stomatal kinetics with xylem vulnerability to cavitation [vulnerability curve (VC)] leads to different levels of isohydry/anisohydry in different plant species/cultivars. In this study, this hypothesis is tested in Vitis vinifera cultivars displaying contrasting stomatal behavior under drought stress. The cv Montepulciano (MP, near-isohydric) and Sangiovese (SG, anisohydric) were compared in terms of stomatal response to leaf and stem water potential, as possibly correlated to different petiole hydraulic conductivity (k(petiole)) and VC, as well as to leaf water relations parameters. MP leaves showed almost complete stomatal closure at higher leaf and stem water potentials than SG leaves. Moreover, MP petioles had higher maximum k(petiole) and were more vulnerable to cavitation than SG. Water potential at the turgor loss point was higher in MP than in SG. In SG, the percentage reduction of stomatal conductance (PLg(s)) under water stress was almost linearly correlated with corresponding percentage loss of k(petiole) (PLC), while in MP PLg(s) was less influenced by PLC. Our results suggest that V. vinifera near-isohydric and anisohydric genotypes differ in terms of xylem vulnerability to cavitation as well as in terms of k(petiole) and that the coordination of these traits leads to their different stomatal responses under water stress conditions.
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Affiliation(s)
- Sergio Tombesi
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, Perugia, 06121, Italy
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22
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Analysis of HRCT-derived xylem network reveals reverse flow in some vessels. J Theor Biol 2013; 333:146-55. [PMID: 23743143 DOI: 10.1016/j.jtbi.2013.05.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Revised: 04/05/2013] [Accepted: 05/23/2013] [Indexed: 11/20/2022]
Abstract
Long distance water and nutrient transport in plants is dependent on the proper functioning of xylem networks, a series of interconnected pipe-like cells that are vulnerable to hydraulic dysfunction as a result of drought-induced embolism and/or xylem-dwelling pathogens. Here, flow in xylem vessels was modeled to determine the role of vessel connectivity by using three dimensional xylem networks derived from High Resolution Computed Tomography (HRCT) images of grapevine (Vitis vinifera cv. 'Chardonnay') stems. Flow in 4-27% of the vessel segments (i.e. any section of vessel elements between connection points associated with intervessel pits) was found to be oriented in the direction opposite to the bulk flow under normal transpiration conditions. In order for the flow in a segment to be in the reverse direction, specific requirements were determined for the location of connections, distribution of vessel endings, diameters of the connected vessels, and the conductivity of the connections. Increasing connectivity and decreasing vessel length yielded increasing numbers of reverse flow segments until a maximum value was reached, after which more interconnected networks and smaller average vessel lengths yielded a decrease in the number of reverse flow segments. Xylem vessel relays also encouraged the formation of reverse flow segments. Based on the calculated flow rates in the xylem network, the downward spread of Xylella fastidiosa bacteria in grape stems was modeled, and reverse flow was shown to be an additional mechanism for the movement of bacteria to the trunk of grapevine.
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23
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Sun Q, Sun Y, Walker MA, Labavitch JM. Vascular occlusions in grapevines with Pierce's disease make disease symptom development worse. PLANT PHYSIOLOGY 2013; 161:1529-41. [PMID: 23292789 PMCID: PMC3585614 DOI: 10.1104/pp.112.208157] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 01/02/2013] [Indexed: 05/18/2023]
Abstract
Vascular occlusions are common structural modifications made by many plant species in response to pathogen infection. However, the functional role(s) of occlusions in host plant disease resistance/susceptibility remains controversial. This study focuses on vascular occlusions that form in stem secondary xylem of grapevines (Vitis vinifera) infected with Pierce's disease (PD) and the impact of occlusions on the hosts' water transport and the systemic spread of the causal bacterium Xylella fastidiosa in infected vines. Tyloses are the predominant type of occlusion that forms in grapevine genotypes with differing PD resistances. Tyloses form throughout PD-susceptible grapevines with over 60% of the vessels in transverse sections of all examined internodes becoming fully blocked. By contrast, tylose development was mainly limited to a few internodes close to the point of inoculation in PD-resistant grapevines, impacting only 20% or less of the vessels. The extensive vessel blockage in PD-susceptible grapevines was correlated to a greater than 90% decrease in stem hydraulic conductivity, compared with an approximately 30% reduction in the stems of PD-resistant vines. Despite the systemic spread of X. fastidiosa in PD-susceptible grapevines, the pathogen colonized only 15% or less of the vessels in any internode and occurred in relatively small numbers, amounts much too small to directly block the vessels. Therefore, we concluded that the extensive formation of vascular occlusions in PD-susceptible grapevines does not prevent the pathogen's systemic spread in them, but may significantly suppress the vines' water conduction, contributing to PD symptom development and the vines' eventual death.
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Affiliation(s)
- Qiang Sun
- Department of Biology, University of Wisconsin, Stevens Point, WiI 54481, USA.
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24
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Brodersen CR, Choat B, Chatelet DS, Shackel KA, Matthews MA, McElrone AJ. Xylem vessel relays contribute to radial connectivity in grapevine stems (Vitis vinifera and V. arizonica; Vitaceae). AMERICAN JOURNAL OF BOTANY 2013; 100:314-321. [PMID: 23345417 DOI: 10.3732/ajb.1100606] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
PREMISE OF THE STUDY Xylem network connections play an important role in water and nutrient transport in plants, but also facilitate the spread of air embolisms and xylem-dwelling pathogens. This study describes the structure and function of vessel relays found in grapevine xylem that form radial and tangential connections between spatially discrete vessels. METHODS We used high-resolution computed tomography, light microscopy, scanning electron microscopy, and single-vessel dye injections to characterize vessel relays in stems and compare their distributions and structure in two Vitis species. KEY RESULTS Vessel relays were composed of 1-8 narrow diameter (~25 µm) vessel elements and were oriented radially, connecting vessels via scalariform pitting within a xylem sector delineated by rays. The functional connectedness of vessels linked by vessel relays was confirmed with single-vessel dye injections. In 4.5-cm sections of stem tissue, there were 26% more vessel relays in V. vinifera compared with V. arizonica. • CONCLUSIONS Because of their spatial distribution within Vitis xylem, vessel relays increase the connectivity between vessels that would otherwise remain isolated. Differences in vessel relays between Vitis species suggest these anatomical features could contribute to disease and embolism resistance in some species.
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Affiliation(s)
- Craig R Brodersen
- Department of Horticultural Science, Citrus Research & Education Center, University of Florida, Lake Alfred, FL 33850, USA
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25
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Wallis CM, Chen J. Grapevine phenolic compounds in xylem sap and tissues are significantly altered during infection by Xylella fastidiosa. PHYTOPATHOLOGY 2012; 102:816-26. [PMID: 22671027 DOI: 10.1094/phyto-04-12-0074-r] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Pierce's disease of grapevine (PD), caused by the bacterial pathogen Xylella fastidiosa, remains a serious problem for grape production in California and elsewhere. This research examined induction of phenolic compounds in grapevines ('Thompson Seedless') infected with X. fastidiosa over a 6-month period. Two months postinoculation with X. fastidiosa, catechin, digalloylquinic acid, and astringin were found at greater levels in xylem sap; multiple catechins, procyanidins, and stilbenoids were found at greater levels in xylem tissues; and precursors to lignin and condensed tannins were found at greater levels in xylem cell walls. However, such large-scale inductions of phenolic compounds were not observed 4 months after inoculation. Six months after inoculation, infected plants had significantly reduced phenolic levels in xylem sap and tissues when compared with control plants, including lowered levels of lignin and condensed tannins. At 6 months, PD symptoms were severe in infected plants and most photosynthetic tissue was abscised. These results suggest that, even though grapevine hosts may initially respond to X. fastidiosa infections with increased production of phenolic compounds, ultimately, PD causes grapevines to enter a state of decline whereby diseased hosts no longer have the resources to support secondary metabolite production, including defense-associated phenolic compounds.
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Affiliation(s)
- Christopher M Wallis
- United States Department of Agriculture - Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, Palier, CA 93648, USA.
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26
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Garcia AL, Torres SCZ, Heredia M, Lopes SA. Citrus Responses to Xylella fastidiosa Infection. PLANT DISEASE 2012; 96:1245-1249. [PMID: 30727147 DOI: 10.1094/pdis-10-11-0868-re] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The xylem-limited bacterium Xylella fastidosa causes the widely disseminated citrus variegated chlorosis disease (CVC). In Brazil, CVC has been known for more than 20 years and affects only sweet orange. Lime and mandarin have remained free of symptoms despite the high inoculum pressure. Knowing the mechanisms underlying this apparent resistance is important to devise new disease control strategies. The reaction of commercial sweet orange ('Caipira', 'Natal', 'Pêra', and 'Valencia'), lime (Mexican and Persian), mandarin ('Cleopatra', 'Cravo', 'Ponkan', and 'Sunki'), and the acid citrus species Rangpur to X. fastidiosa was compared in artificially inoculated seedlings, which were assessed for symptom expression, pathogen isolation, and the amount of apparently occluded xylem vessels in cross-sectioned leaf petioles. Only the sweet orange expressed typical CVC symptoms, varying from 53.8% in Valencia to 63.0% in Caipira. Average percentages of positive isolations (pi) and occluded vessels (ov) were higher in sweet orange (pi= 59.2 to 75.0; ov = 10.7 to 25.8) than mandarin (pi = 2.3 to 16.3; ov = 1.4 to 4.0), lime (pi = 0 to 5.4; ov = 0 to 2.1), or Rangpur (pi = 1,9; ov = 1.1). There were no obvious differences in xylem anatomy among all citrus varieties, suggesting that the mechanisms of resistance to CVC are not related to any physical variation in xylem structure.
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Affiliation(s)
- A L Garcia
- Universidade de Ribeirão Preto, Av. Costábile Romano, 2.201, Ribeirão Preto, SP, 14096-900, Brazil
| | - S C Z Torres
- Universidade de Ribeirão Preto, Av. Costábile Romano, 2.201, Ribeirão Preto, SP, 14096-900, Brazil
| | - M Heredia
- Universidade de Ribeirão Preto, Av. Costábile Romano, 2.201, Ribeirão Preto, SP, 14096-900, Brazil
| | - S A Lopes
- Fundo de Defesa da Citricultura, Av. Dr. Adhemar Pereira de Barros, 201, Araraquara, SP, 14.807-040, Brazil
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27
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Colas S, Afoufa-Bastien D, Jacquens L, Clément C, Baillieul F, Mazeyrat-Gourbeyre F, Monti-Dedieu L. Expression and in situ localization of two major PR proteins of grapevine berries during development and after UV-C exposition. PLoS One 2012; 7:e43681. [PMID: 22937077 PMCID: PMC3427166 DOI: 10.1371/journal.pone.0043681] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 07/24/2012] [Indexed: 11/18/2022] Open
Abstract
In grapevine Vitis vinifera L. cv Pinot noir, the Pathogenesis-Related (PR) proteins CHI4D and TL3 are among the most abundant extractable PR proteins of ripe berries and accumulate during berry ripening from véraison until full maturation. Evidence was supplied in favor of the involvement of these two protein families in plant defense mechanisms and plant development. In order to better understand CHI4D and TL3 function in grapevine, we analyzed their temporal and spatial pattern of expression during maturation and after an abiotic stress (UV-C) by in situ hybridization (ISH) and immunohistolocalization. In ripening berries, CHI4D and TL3 genes were mainly expressed in the exocarp and around vascular bundles of the mesocarp. In UV-C exposed berries, CHI4D and TL3 gene expression was strongly induced before véraison. Corresponding proteins localized in the exocarp and, to a lesser extent, around vascular bundles of the mesocarp. The spatial and temporal accumulation of the two PR proteins during berry maturation and after an abiotic stress is discussed in relation to their putative roles in plant defense.
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Affiliation(s)
- Steven Colas
- Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne - EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne-Ardenne, BP 1039, Reims, France
| | - Damien Afoufa-Bastien
- Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne - EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne-Ardenne, BP 1039, Reims, France
| | - Lucile Jacquens
- Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne - EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne-Ardenne, BP 1039, Reims, France
| | - Christophe Clément
- Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne - EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne-Ardenne, BP 1039, Reims, France
| | - Fabienne Baillieul
- Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne - EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne-Ardenne, BP 1039, Reims, France
| | - Florence Mazeyrat-Gourbeyre
- Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne - EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne-Ardenne, BP 1039, Reims, France
| | - Laurence Monti-Dedieu
- Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne - EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne-Ardenne, BP 1039, Reims, France
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