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Heredia A, Benítez JJ, González Moreno A, Domínguez E. Revisiting plant cuticle biophysics. THE NEW PHYTOLOGIST 2024. [PMID: 39061101 DOI: 10.1111/nph.20009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 07/08/2024] [Indexed: 07/28/2024]
Abstract
The plant cuticle is located at the interface of the plant with the environment, thus acting as a protective barrier against biotic and abiotic external stress factors, and regulating water loss. Additionally, it modulates mechanical stresses derived from internal tissues and also from the environment. Recent advances in the understanding of the hydric, mechanical, thermal, and, to a lower extent, optical and electric properties of the cuticle, as well as their phenomenological connections and relationships are reviewed. An equilibrium based on the interaction among the different biophysical properties is essential to ensure plant growth and development. The notable variability reported in cuticle geometry, surface topography, and microchemistry affects the analysis of some biophysical properties of the cuticle. This review aimed to provide an updated view of the plant cuticle, understood as a modification of the cell wall, in order to establish the state-of-the-art biophysics of the plant cuticle, and to serve as an inspiration for future research in the field.
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Affiliation(s)
- Antonio Heredia
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Universidad de Málaga, E-29010, Málaga, Spain
| | - José J Benítez
- Instituto de Ciencia de Materiales de Sevilla, Centro Mixto Consejo Superior de Investigaciones Científicas-Universidad de Sevilla, E-41092, Seville, Spain
| | - Ana González Moreno
- Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Universidad de Málaga, E-29010, Málaga, Spain
| | - Eva Domínguez
- Departamento de Mejora Genética y Biotecnología, Estación Experimental La Mayora, Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", Universidad de Málaga-Consejo Superior de Investigaciones Científicas, E-29750, Málaga, Spain
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2
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Elliott J, Cortvriend J, Depietra G, Brennan C, Compton RG. Kinetics of Lipophilic Pesticide Uptake by Living Maize. ACS AGRICULTURAL SCIENCE & TECHNOLOGY 2023; 3:445-454. [PMID: 37206884 PMCID: PMC10189725 DOI: 10.1021/acsagscitech.3c00042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 05/21/2023]
Abstract
We report the uptake of a lipophilic fungicide into the cuticle of living leaves of young maize from droplets of a suspension concentrate. The action of a "coffee-ring" effect is demonstrated during fungicide formulation drying, and the fungicide particle distribution is quantified. We develop a simple, two-dimensional model of uptake leading to a "reservoir" of cuticular fungicide. This model allows inferences of physicochemical properties for fungicides inside the cuticular medium. The diffusion coefficient closely agrees with literature penetration experiments (Dcut ≈ 10-18 m2 s-1). The logarithm of the inferred cuticle-water partition coefficient log10 Kcw = 6.03 ± 0.04 is consistent with ethyl acetate as a model solvent for the maize cuticle. Two limiting kinetic uptake regimes are inferred from the model for short and long times, with the transition resulting from longitudinal saturation of the cuticle beneath the droplet. We discuss the strengths, limitations, and generalizability of our model within the "cuticle reservoir" approximation.
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Affiliation(s)
- Joseph
R. Elliott
- Department
of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, Great
Britain
| | - Joseph Cortvriend
- Jealott’s
Hill International Research Centre, Syngenta
Ltd., Bracknell, Berkshire RG42 6EY, Great Britain
| | - Giovambattista Depietra
- Jealott’s
Hill International Research Centre, Syngenta
Ltd., Bracknell, Berkshire RG42 6EY, Great Britain
| | - Colin Brennan
- Jealott’s
Hill International Research Centre, Syngenta
Ltd., Bracknell, Berkshire RG42 6EY, Great Britain
| | - Richard G. Compton
- Department
of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, Great
Britain
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3
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Prigioniero A, Zuzolo D, Niinemets Ü, Postiglione A, Mercurio M, Izzo F, Trifuoggi M, Toscanesi M, Scarano P, Tartaglia M, Sciarrillo R, Guarino C. Particulate matter and polycyclic aromatic hydrocarbon uptake in relation to leaf surface functional traits in Mediterranean evergreens: Potentials for air phytoremediation. JOURNAL OF HAZARDOUS MATERIALS 2022; 435:129029. [PMID: 35525010 DOI: 10.1016/j.jhazmat.2022.129029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 06/14/2023]
Abstract
We explored relationships between particulate matter (PM) and polycyclic aromatic hydrocarbon (PAHs) leaf concentrations, uptake rates and leaf surface functional traits in four Mediterranean evergreen trees (Chamaerops humilis, Citrus × aurantium, Magnolia grandiflora, and Quercus ilex) during a dry month. Pollutant leaf concentration at different dates and uptake rate were correlated. We quantified PM by gravimetric analysis, PAHs were extracted from intact and dewaxed leaves and analyzed by GC-MS, and cuticle thickness, number and surface of stomata (Ns and SS) and trichomes (Nt and St) were determined by optical microscopy. Infrared spectroscopy was used to investigate the leaves surfaces composition and assess esterification index (E). Studied species were characterized by unique combinations of functional traits and pollutant uptake capacities. PM10 uptake scaled positively with SS, St and upper cuticle thickness (Tc,u) across species. PM2.5 uptake scaled positively with Tc,u, and thicker cuticles were also associated with greater shares of uptake of hydrophobic PM fractions. Uptakes of different fractions of PAH were generally weakly related to different leaf functional traits, except for some correlations with E and SS. We conclude that both plant surface morphological and chemical leaf traits influence PM and PAH retention, unveiling their potential role in air phytoremediation.
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Affiliation(s)
- Antonello Prigioniero
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy
| | - Daniela Zuzolo
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy.
| | - Ülo Niinemets
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Fr. R. Kreutzwaldi 1, Tartu 51006, Estonia
| | - Alessia Postiglione
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy
| | - Mariano Mercurio
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy
| | - Francesco Izzo
- Department of Earth Sciences, Environment and Resources, University of Naples Federico II, via Cintia, Naples 80126, Italy
| | - Marco Trifuoggi
- Department of Chemical Sciences, University of Naples Federico II, via Cintia, Naples 80126, Italy
| | - Maria Toscanesi
- Department of Chemical Sciences, University of Naples Federico II, via Cintia, Naples 80126, Italy
| | - Pierpaolo Scarano
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy
| | - Maria Tartaglia
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy
| | - Rosaria Sciarrillo
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy
| | - Carmine Guarino
- Department of Science and Technology, University of Sannio, via de Sanctis snc, Benevento 82100, Italy
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4
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Tredenick EC, Stuart-Williams H, Enge TG. Materials on Plant Leaf Surfaces Are Deliquescent in a Variety of Environments. FRONTIERS IN PLANT SCIENCE 2022; 13:722710. [PMID: 35903227 PMCID: PMC9315345 DOI: 10.3389/fpls.2022.722710] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
Materials on plant leaf surfaces that attract water impact penetration of foliar-applied agrochemicals, foliar water uptake, gas exchange, and stomatal density. Few studies are available on the nature of these substances, and we quantify the hygroscopicity of these materials. Water vapor sorption experiments on twelve leaf washes of sample leaves were conducted and analyzed with inductively coupled plasma-optical emission spectroscopy (ICP-OES) and X-ray diffraction. All leaf surface materials studied were hygroscopic. Oils were found on the surface of the Eucalyptus studied. For mangroves that excrete salt to the leaf surfaces, significant sorption occurred at high humidity of a total of 316 mg (~0.3 ml) over 6-10 leaves and fitted a Guggenheim, Anderson, and de Böer sorption isotherm. Materials on the plant leaf surface can deliquesce and form an aqueous solution in a variety of environments where plants grow, including glasshouses and by the ocean, which is an important factor when considering plant-atmosphere relations.
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Affiliation(s)
- E. C. Tredenick
- Division of Plant Sciences, ARC Centre of Excellence in Translational Photosynthesis, Research School of Biology, Australian National University, Canberra, ACT, Australia
- Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - H. Stuart-Williams
- Division of Plant Sciences, ARC Centre of Excellence in Translational Photosynthesis, Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - T. G. Enge
- Research School of Earth Sciences, Australian National University, Canberra, ACT, Australia
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5
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Elliott JR, Compton RG. Modeling Transcuticular Uptake from Particle-Based Formulations of Lipophilic Products. ACS AGRICULTURAL SCIENCE & TECHNOLOGY 2022; 2:603-614. [PMID: 35756577 PMCID: PMC9214695 DOI: 10.1021/acsagscitech.2c00029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/14/2022] [Accepted: 04/20/2022] [Indexed: 12/04/2022]
Abstract
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We
report a mathematical model for the uptake of lipophilic agrochemicals
from dispersed spherical particles within a formulation droplet across
the leaf cuticle. Two potential uptake pathways are identified: direct
uptake via physical contact between the cuticle and particle and indirect
uptake via initial release of material into the formulation droplet
followed by partition across the cuticle-formulation interface. Numerical
simulation is performed to investigate the relevance of the particle-cuticle
contact angle, the release kinetics of the particle, and the particle
size relative to the cuticle thickness. Limiting cases for each pathway
are identified and investigated. The input of typical physicochemical
parameters suggests that the indirect pathway is generally dominant
unless pesticide release is under strict kinetic control. Evidence
is presented for a hitherto unrecognized “leaching effect”
and the mutual exclusivity of the two pathways.
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Affiliation(s)
- Joseph R. Elliott
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, Great Britain
| | - Richard G. Compton
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, Great Britain
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Tredenick EC, Farquhar GD. Dynamics of moisture diffusion and adsorption in plant cuticles including the role of cellulose. Nat Commun 2021; 12:5042. [PMID: 34413297 PMCID: PMC8377085 DOI: 10.1038/s41467-021-25225-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 07/22/2021] [Indexed: 02/07/2023] Open
Abstract
Food production must increase significantly to sustain a growing global population. Reducing plant water loss may help achieve this goal and is especially relevant in a time of climate change. The plant cuticle defends leaves against drought, and so understanding water movement through the cuticle could help future proof our crops and better understand native ecology. Here, via mathematical modelling, we identify mechanistic properties of water movement in cuticles. We model water sorption in astomatous isolated cuticles, utilising three separate pathways of cellulose, aqueous pores and lipophilic. The model compares well to data both over time and humidity gradients. Sensitivity analysis shows that the grouping of parameters influencing plant species variations has the largest effect on sorption, those influencing cellulose are very influential, and aqueous pores less so but still relevant. Cellulose plays a significant role in diffusion and adsorption in the cuticle and the cuticle surfaces.
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Affiliation(s)
- E C Tredenick
- ARC Centre of Excellence in Translational Photosynthesis, Division of Plant Science, Research School of Biology, The Australian National University, Canberra, ACT, Australia.
| | - G D Farquhar
- ARC Centre of Excellence in Translational Photosynthesis, Division of Plant Science, Research School of Biology, The Australian National University, Canberra, ACT, Australia
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7
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Márquez DA, Stuart-Williams H, Farquhar GD. An improved theory for calculating leaf gas exchange more precisely accounting for small fluxes. NATURE PLANTS 2021; 7:317-326. [PMID: 33649595 DOI: 10.1038/s41477-021-00861-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
The widely used theory for gas exchange proposed by von Caemmerer and Farquhar (vCF) integrates molar fluxes, mole fraction gradients and ternary effects but does not account for cuticular fluxes, for separation of the leaf surface conditions or for ternary effects within the boundary layer. The magnitude of cuticular conductance to water (gcw) is a key factor for determining plant survival in drought but is difficult to measure and often neglected in routine gas exchange studies. The vCF ternary effect is applied to the total flux without the recognition of different pathways that are affected by it. These simplifications lead to errors in estimations of stomatal conductance, intercellular carbon dioxide concentration (Ci) and other gas exchange parameters. The theory presented here is a more precise physical approach to the electrical resistance analogy for gas exchange, resulting in a more accurate calculation of gas exchange parameters. Additionally, we extend our theory, using physiological concepts, to create a model that allows us to calculate cuticular conductance to water.
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Affiliation(s)
- Diego A Márquez
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Hilary Stuart-Williams
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Graham D Farquhar
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia.
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8
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Fernández V, Gil-Pelegrín E, Eichert T. Foliar water and solute absorption: an update. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:870-883. [PMID: 33219553 DOI: 10.1111/tpj.15090] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 11/17/2020] [Indexed: 06/11/2023]
Abstract
The absorption of water and solutes by plant leaves has been recognised since more than two centuries. Given the polar nature of water and solutes, the mechanisms of foliar uptake have been proposed to be similar for water and electrolytes, including nutrient solutions. Research efforts since the 19th century focussed on characterising the properties of cuticles and applying foliar sprays to crop plants as a tool for improving crop nutrition. This was accompanied by the development of hundreds of studies aimed at characterising the chemical and structural nature of plant cuticles from different species and the mechanisms of cuticular and, to a lower extent, stomatal penetration of water and solutes. The processes involved are complex and will be affected by multiple environmental, physico-chemical and physiological factors which are only partially clear to date. During the last decades, the body of evidence that water transport across leaf surfaces of native species may contribute to water balances (absorption and loss) at an ecosystem level has grown. Given the potential importance of foliar water absorption for many plant species and ecosystems as shown in recent studies, the aim of this review is to first integrate current knowledge on plant surface composition, structure, wettability and physico-chemical interactions with surface-deposited matter. The different mechanisms of foliar absorption of water and electrolytes and experimental procedures for tracing the uptake process are discussed before posing several outstanding questions which should be tackled in future studies.
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Affiliation(s)
- Victoria Fernández
- Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Universidad Politécnica de Madrid, Madrid, 28040, Spain
| | - Eustaquio Gil-Pelegrín
- Unidad de Recursos Forestales, Centro de Investigación y Tecnología Agroalimentaria, Gobierno de Aragón, Zaragoza, 50059, Spain
| | - Thomas Eichert
- University of Applied Sciences Erfurt, Erfurt, 99051, Germany
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9
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Cu-chitosan nano-net improves keeping quality of tomato by modulating physio-biochemical responses. Sci Rep 2020; 10:21914. [PMID: 33318539 PMCID: PMC8097068 DOI: 10.1038/s41598-020-78924-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 10/02/2020] [Indexed: 12/20/2022] Open
Abstract
Minimizing the post-harvest losses in fruits and vegetables is one of the challenging tasks in agriculture. To address this issue, we report nano-net of Cu-chitosan nanoparticles (Cu-chitosan NPs) which has the ability to extend the shelf-life of stored tomato. The application of Cu-chitosan NPs (0.01–0.04%) significantly curtailed microbial decay (< 5 versus > 50% in control), physiological loss in weight (14.36 versus 28.13% in control), respiration rate (0.01173 versus 0.01879 g CO2 kg−1 h−1) and maintained fruit firmness (34.0 versus 17.33 N in control) during storage. Further, these NPs significantly retarded loss of titratable acidity, retained total soluble solids, total and reducing sugars, lycopene, ascorbic acid and inhibited polyphenol oxidase. Likewise, NPs effectively preserved L* (lightness), a* (red/green) and b* (blue/yellow) values and maintained organoleptic score. Scanning electron microscopy study confirmed that Cu-chitosan NPs orchestrate into an invisible-intangible nano-net over tomato surface which may plausibly act as a potential barrier at all possible openings (stem scar, cuticle wax, lenticels, and aquaporins) to control microbial infection, moisture loss, gas exchanges and respiration rate. Overall, nano-net extended keeping quality of tomatoes up to 21 days at room temperature (27 ± 2 °C, 55 ± 2% relative humidity).
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10
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Tredenick EC, Farrell TW, Forster WA. Mathematical Modelling of Hydrophilic Ionic Fertiliser Diffusion in Plant Cuticles: Lipophilic Surfactant Effects. PLANTS (BASEL, SWITZERLAND) 2019; 8:E202. [PMID: 31269757 PMCID: PMC6681217 DOI: 10.3390/plants8070202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 06/24/2019] [Accepted: 06/28/2019] [Indexed: 01/05/2023]
Abstract
The global agricultural industry requires improved efficacy of sprays being applied to weeds and crops to increase financial returns and reduce environmental impact. Enhancing foliar penetration is one way to improve efficacy. Within the plant leaf, the cuticle is the most significant barrier to agrochemical diffusion. It has been noted that a comprehensive set of mechanisms for ionic active ingredient (AI) penetration through plant leaves with surfactants is not well defined, and oils that enhance penetration have been given little attention. The importance of a mechanistic mathematical model has been noted previously in the literature. Two mechanistic mathematical models have been previously developed by the authors, focusing on plant cuticle penetration of calcium chloride through tomato fruit cuticles. The models included ion binding and evaporation with hygroscopic water absorption, along with the ability to vary the AI concentration and type, relative humidity, and plant species. Here, we further develop these models to include lipophilic adjuvant effects, as well as the adsorption and desorption, of compounds on the cuticle surface with a novel Adaptive Competitive Langmuir model. These modifications to a penetration model provide a novel addition to the literature. We validate our theoretical model results against appropriate experimental data, discuss key sensitivities, and relate theoretical predictions to physical mechanisms. The results indicate the addition of the desorption mechanism may be one way to predict increased penetration at late times, and the sensitivity of model parameters compares well to those present in the literature.
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Affiliation(s)
- Eloise C Tredenick
- School of Mathematical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001, Australia.
| | - Troy W Farrell
- School of Mathematical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001, Australia.
- ARC Centre of Excellence for Mathematical and Statistical Frontiers (ACEMS), Queensland University of Technology, Brisbane, QLD 4001, Australia.
| | - W Alison Forster
- Plant Protection Chemistry NZ Ltd., PO Box 6282, Rotorua, Bay of Plenty 3043, New Zealand
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11
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Tredenick EC, Farrell TW, Forster WA. Mathematical Modeling of Diffusion of a Hydrophilic Ionic Fertilizer in Plant Cuticles: Surfactant and Hygroscopic Effects. FRONTIERS IN PLANT SCIENCE 2018; 9:1888. [PMID: 30619434 PMCID: PMC6306450 DOI: 10.3389/fpls.2018.01888] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 12/06/2018] [Indexed: 05/30/2023]
Abstract
The agricultural industry requires improved efficacy of sprays being applied to crops and weeds to reduce their environmental impact and increase financial returns. One way to improve efficacy is by enhancing foliar penetration. The plant leaf cuticle is the most significant barrier to agrochemical diffusion within the leaf. The importance of a mechanistic mathematical model has been noted previously in the literature, as each penetration experiment is dictated by its specific parameters, namely plant species, environmental conditions such as relative humidity and spray formulation including adjuvant addition. A mechanistic mathematical model has been previously developed by the authors, focusing on plant cuticle diffusion of calcium chloride through tomato fruit cuticles including pore swelling, ion binding and evaporation, along with the ability to vary the active ingredient concentration and type, relative humidity and plant species. Here we further develop this model to include adjuvant effects as well as the hygroscopic nature of deliquescent ionic solutions with evaporation on the cuticle surface. These modifications to a penetration and evaporation model provide a novel addition to the literature and allow the model to be applied to many types of evaporating ionic hygroscopic solutions on many types of substrates, not just plant cuticles. We validate our theoretical model results against appropriate experimental data, discuss key sensitivities and relate theoretical predictions to physical mechanisms. The important governing mechanisms influencing surfactant enhanced penetration of ionic active through plant cuticles were found to be aqueous pore radius, pore density, cuticle thickness and initial contact angle of the applied droplet; ion binding, relative humidity and evaporation including hygroscopic water absorption parameters for point of deliquescence. The sensitivity analysis indicated surfactants increase penetration by changing the point of deliquescence of a solution, which alters the water absorption and the initial contact angle, which alters the number of pores under the droplet. The results of the validation and sensitivity analysis imply that this model accounts for many of the mechanisms governing penetration in plant cuticles.
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Affiliation(s)
- E. C. Tredenick
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - T. W. Farrell
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
- ARC Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, Brisbane, QLD, Australia
| | - W. A. Forster
- Plant Protection Chemistry NZ Ltd., Rotorua, New Zealand
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12
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Bahamonde HA, Gil L, Fernández V. Surface Properties and Permeability to Calcium Chloride of Fagus sylvatica and Quercus petraea Leaves of Different Canopy Heights. FRONTIERS IN PLANT SCIENCE 2018; 9:494. [PMID: 29720987 PMCID: PMC5915543 DOI: 10.3389/fpls.2018.00494] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 04/03/2018] [Indexed: 05/08/2023]
Abstract
Plant surfaces have a considerable degree of chemical and physical variability also in relation to different environmental conditions, organs and state of development. The potential changes on plant surface properties in association with environmental variations have been little explored so far. Using two model tree species (i.e., Quercus petraea, sessile oak and Fagus sylvatica, beech) growing in 'Montejo de la Sierra Forest,' we examined various traits of the abaxial and adaxial surface of leaves of both species collected at a height of approximately 15 m (top canopy), versus 3.5-5.5 m for beech and sessile oak, lower canopy leaves. Leaf surface ultra-structure was analyzed by scanning and transmission electron microscopy, and the surface free energy and related parameter were estimated after measuring drops of 3 liquids with different degrees of polarity and apolarity. The permeability of the adaxial and abaxial surface of top and bottom canopy leaves to CaCl2 was estimated by depositing 2 drops of 3-4 μl per cm2 and comparing the concentration of Ca in leaf tissues 24 h after treatment, and also Ca and Cl concentrations in the washing liquid. Higher Ca concentrations were recorded after the application of CaCl2 drops onto the veins and adaxial blade of top canopy beech leaves, while no significant evidence for foliar Ca absorption was gained with sessile oak leaves. Surprisingly, high amounts of Cl were recovered after washing untreated, top canopy beach and sessile oak leaves with deionised water, a phenomenon which was not traced to occur on lower canopy leaves of both species. It is concluded that the surface of the two species analyzed is heterogeneous in nature and may have areas favoring the absorption of water and solutes as observed for the veins of beech leaves.
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Affiliation(s)
- Héctor A. Bahamonde
- Instituto Nacional de Tecnología Agropecuaria, Buenos Aires, Argentina
- Department of Natural Resources, Universidad Nacional de la Patagonia Austral, Río Gallegos, Argentina
| | - Luis Gil
- Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Technical University of Madrid, Madrid, Spain
| | - Victoria Fernández
- Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Technical University of Madrid, Madrid, Spain
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