Selected Publications

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Roberts lab publications

Prestt, A.J. and Roberts, M.R. (2023) Specific suppression of vascular wilt disease of onion is linked with fungal soil community structure. Rhizosphere 25: 100671.

Abstract The soil microbiome plays an important role in plant health and is therefore being investigated as a target to develop new approaches for sustainable crop protection. Here, we aimed to investigate the roles of bacterial and fungal communities in suppression of vascular wilt disease caused by Fusarium oxysporum in soils used for the cropping of onion (Allium cepae).   Read more...

Catoni, M., Alvarez-Venegas, R., Worrall, D., Holroyd, G., Barraza, A., Luna, E., Ton, J. and Roberts, M.R. (2022) Long-lasting defence priming by β-aminobutyric acid in tomato is marked by genome-wide changes in DNA methylation. Frontiers in Plant Science 13: 836326.

Abstract Exposure of plants to stress conditions or to certain chemical elicitors can establish a primed state, whereby responses to future stress encounters are enhanced. Here, we characterise epigenetic changes in tomato plants primed for pathogen resistance by treatment with β-aminobutyric acid (BABA). We used whole genome bisulphite sequencing to construct tomato methylomes from control plants and plants treated with BABA at the seedling stage, and a parallel transcriptome analysis to identify genes primed for the response to inoculation by Botrytis cinerea. Read more...

Bazzarelli, F., Mazzei, R., Papaioannou, E., Giannakopoulos, V., Roberts, M.R., Giorno, L. (2022) Biorefinery of tomato leaves by integrated extraction and membrane processes to obtain fractions that enhance induced resistance against Pseudomonas syringae infection. Membranes 12: 585

Abstract Tomato leaves have been shown to contain significant amounts of important metabolites involved in protection against abiotic and biotic stress and/or possessing important therapeutic properties. In this work, a systematic study was carried out to evaluate the potential of a sustainable process for the fractionation of major biomolecules from tomato leaves, by combining aqueous extraction and membrane processes.   Read more...

López Sánchez, A., Pascual-Pardo, D., Furci, L., Roberts, M.R. and Ton, J. (2021) Costs and Benefits of Transgenerational Induced Resistance in Arabidopsis. Front. Plant Sci. 12: 644999

Abstract ... the evolutionary and ecological significance of transgenerational induced resistance (t-IR) is poorly understood because a clear understanding of how parents interpret environmental cues in relation to the effectiveness, stability, and anticipated ecological costs of t-IR is lacking. Here, we have used a full factorial design to study the specificity, costs, and transgenerational stability of t-IR. Read more...

Butler, H.J., Martin, F.L., Roberts, M.R., Adams, S., McAinsh M.R. (2019) Observation of nutrient uptake at the adaxial surface of leaves of tomato (Solanum lycopersicum) using Raman spectroscopy. Analytical Letters 53: 536-562

Abstract Foliar application of nutrient fertilizers is standard practice in agricultural environments, and has been shown to increase crop yield and quality more efficiently and economically than soil-based fertilizers. ... Herein we describe a method to observe nitrate (NO3−) uptake at the adaxial leaf surface to determine the efficacy of foliar fertilizers. We use Raman microspectroscopy as a sensitive approach to monitor NO3−...   Read more...

Srivastava A.K., Orosa B., Singh P., Cummins I., Walsh C., Zhang C., Grant M., Roberts M.R., Anand G.S., Fitches E., Sadanandom A. (2018) SUMO suppresses the activity of the jasmonic acid receptor CORONATINE INSENSITIVE 1. Plant Cell 30: 2099–2115 

Abstract Plants respond rapidly to sudden environmental cues, often responding prior to changes in the hormone levels that coordinate these responses. How this is achieved is not fully understood. The integrative role of the phytohormone jasmonic acid (JA) relies upon the plant's ability to control the levels of JASMONATE ZIM (JAZ) domain-containing repressor proteins. Here, we demonstrate that regardless of intrinsic JA levels, Small Ubiquitin-like Modifier (SUMO)-conjugated JAZ proteins inhibit the JA receptor CORONATINE INSENSITIVE1 (COI1) from mediating non-SUMOylated JAZ degradation. Read more...

Singh P., Dave A., Vaistij F.E., Worrall D., Holroyd G.H., Wells J.G., Kaminski F., Graham I.A., Roberts M.R. (2017) Jasmonic acid-dependent regulation of seed dormancy following maternal herbivory in Arabidopsis. New Phytologist 214: 1702–1711 

Abstract Maternal biotic stress alters offspring defence phenotypes, but whether it also affects seed dormancy remains unexplored. We exposed Arabidopsis thaliana plants to herbivory and investigated plasticity in germination and defence phenotypes in their offspring, along with the roles of phytohormone signalling in regulating maternal effects. Herbivory generates a jasmonic acid-dependent reduction in seed dormancy, mediated by alteration of gibberellin and abscisic acid signalling. Read more...

Nesbit C.M., Menendez R., Roberts, M.R., Wilby, A. (2016) Associational resistance or susceptibility: the indirect interaction between chemically-defended and non-defended herbivore prey via a shared predator. Oikos 125: 1802-1811 

Abstract Many organisms possess chemical defences against their natural enemies, which render them unpalatable or toxic when attacked or consumed. These chemically-defended organisms commonly occur in communities with non- or less-defended prey, leading to indirect interactions between prey species, mediated by natural enemies. Although the importance of enemy-mediated indirect interactions have been well documented, how the presence of prey chemical defences may affect predation of non-defended prey in terrestrial communities remains unclear. Read more...

Nesbit C.M., Wilby A., Roberts M.R., Menéndez, R. (2015) Selection of aphid prey by a generalist predator: Do prey chemical defences matter? Ecological Entomology 40: 767-775.

Abstract For predators, prey selection should maximise nutrition and minimise fitness costs. In the present study, it was investigated whether a generalist predator [Chrysoperla carnea (Stephens) lacewing larvae] rejected harmful, chemically-defended prey [Brevicoryne brassicae (Linnaeus) aphids] when non-defended prey [Myzus persicae (Sulzer) aphids] were available. Read more...

Shen L., Sun P., Bonnell V.C., Edwards K.J., Hetherington A.M., McAinsh M.R., Roberts M.R. (2015) Measuring stress signalling responses of stomata in isolated epidermis of graminaceous species. Frontiers in Plant Science 6: 533.

Abstract The ability to study stomatal responses in isolated epidermis has been an important factor in elucidating the mechanisms by which stomata respond to environmental stresses. However, such approaches have rarely been applied to study guard cell signalling in the stomata of graminaceous species, in which the guard cells have a markedly different morphology to those in other plants. Here, we demonstrate stoamtal closure assays in isolated abaxial epidermal peels from barley, wheat and Brachypodium distachyon. Read more...

Worrall, D., Holroyd, G.H., Moore, J.P., Glowacz, M., Croft, P., Taylor, J.E., Paul, N.D., Roberts, M.R. (2012) Treating seeds with activators of plant defence generates long lasting priming of resistance to pests and pathogens. New Phytologist 193: 770-778.

Abstract Priming of defence is a strategy employed by plants exposed to stress to enhance resistance against future stress episodes with minimal associated costs on growth. Here, we test the hypothesis that application of priming agents to seeds can result in plants with primed defences. Read more...

Luna E., Bruce T.J.A., Roberts M.R., Flors V., Ton J. (2012) Next generation systemic acquired resistance. Plant Physiology 158: 844-853.

Abstract Systemic acquired resistance (SAR) is a plant immune response to pathogen attack. Recent evidence suggests that plant immunity involves regulation by chromatin remodeling and DNA methylation. We investigated whether SAR can be inherited epigenetically following disease pressure by Pseudomonas syringae pv tomato DC3000 (PstDC3000). Read more...

Short E.F., North K.A., Roberts, M.R., Hetherington, A.M. Shirras, A.D., McAinsh, M.R. (2012) A stress-specific calcium signature regulating an ozone-responsive gene expression network in Arabidopsis. Plant Journal 71: 948-961.

Abstract Changes in gene expression form a key component of the molecular mechanisms by which plants adapt and respond to environmental stresses. There is compelling evidence for the role of stimulus-specific Ca²⁺ signatures in plant stress responses. However, our understanding of how they orchestrate the differential expression of stress-induced genes remains fragmentary. Read more...

Morker K.H., Roberts, M.R. (2011) Light exerts multiple levels of influence on the Arabidopsis wound response. Plant Cell and Environment 34: 717-728.

Abstract Light plays important roles in modulating plant responses to attack by pests and pathogens. Here, we test the hypothesis that darkness modifies the response to wounding, and examine possible mechanisms for such an effect. We investigated changes in the Arabidopsis transcriptome following a light-dark transition and the response to wounding either in the light or in the dark. Read more... 

Naureen, Z., Price, A.H., Hafeez, F.Y, Roberts, M.R. (2009) Identification of rice blast disease-suppressing bacterial strains from the rhizosphere of rice grown in Pakistan. Crop Protection 28: 1052-1060.

Abstract Sixteen bacterial strains isolated from the roots and rhizosphere of rice plants growing in saline and non-saline soils from the Shorkot area of Pakistan were tested for their ability to promote plant growth and reduce the incidence of rice blast disease. When applied to the soil, many of the isolated rhizobacterial strains increased seedling growth and/or suppressed rice blast disease... Read more...

Roberts, M.R. and Paul, N.D. (2006) Seduced by the dark side: integrating molecular and ecological perspectives on the influence of light on plant defence against pests and pathogens. New Phytologist 170: 677-699.

Abstract Plants frequently suffer attack from herbivores and microbial pathogens, and have evolved a complex array of defence mechanisms to resist defoliation and disease. It is well known that plant defences against pests and pathogens are commonly affected by environmental conditions, but the mechanisms by which responses to the biotic and abiotic environments interact are only poorly understood. Read more...

Lancien, M., Roberts, M.R. (2006) Regulation of Arabidopsis 14-3-3 gene expression by GABA. Plant Cell and Environment 29: 1430-1436.

Abstract The function in plants of the non-protein amino acid, gamma-aminobutyric acid (GABA) is poorly understood. In this study, we show that GABA down-regulates the expression of a large subset of 14-3-3 gene family members in Arabidopsis thaliana seedlings in a calcium, ethylene and abscisic acid (ABA)-dependent manner. Read more...

Flor-Henry M., McCabe, T.C., de Bruxelles, G.L., Roberts, M.R. (2004) Use of a highly sensitive two-dimensional luminescence imaging system to monitor endogenous bioluminescence in plant leaves. BMC Plant Biol. 4:19.

Abstract All living organisms emit spontaneous low-level bioluminescence, which can be increased in response to stress. Methods for imaging this ultra-weak luminescence have previously been limited by the sensitivity of the detection systems used. We developed a novel configuration of a cooled charge-coupled device (CCD) for 2-dimensional imaging of light emission from biological material. Read more...

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