About

Tracy Lawson is a Professor of Plant Biology with adjunct and affiliate appointments in Crop Sciences and the Carl R. Woese Institute for Genomic Biology at the University of Illinois. She earned her PhD in Plant Physiology, focusing on heterogeneity in stomatal characteristics, and holds a Bachelor of Science with honors in Applied Biology. Her research centers on the physiology and function of stomata, photosynthesis, and water use efficiency in plants. Lawson's work involves detailed phenotyping and understanding the mechanisms of gas exchange and guard cell function, contributing to agricultural and biological sciences. She has a significant research output including peer-reviewed articles and reviews, with a focus on topics such as stomatal conductance, photosystem efficiency, and plant responses to environmental stresses. Her studies have explored the dynamic relationships between stomatal size and speed, the impact of cell wall water on stomatal function, and the genetic variation influencing photosystem II efficiency in crops like maize. Lawson's research addresses critical challenges in agriculture, including mitigating the impacts of climate change on crop resilience and productivity.

Research topics

• Botany
• Biology
• Physics
• Environmental science
• Biochemistry
• Atmospheric sciences
• Optics
• Ecology
• Agronomy
• Biophysics

Selected publications

• A conversational multi-agent AI system for automated plant phenotyping

  Nature Communications · 2026-04-03

  articleOpen access

  Plant phenotyping increasingly relies on (semi-)automated image-based analysis workflows to improve its accuracy and scalability. However, many existing solutions remain overly complex, difficult to reimplement and maintain, and pose high barriers for users without substantial computational expertise. To address these challenges, we introduce PhenoAssistant: a pioneering AI-driven system that streamlines plant phenotyping via intuitive natural language interaction. PhenoAssistant leverages a large language model to orchestrate a curated toolkit supporting tasks including automated phenotype extraction, data visualisation and automated model training. We validate PhenoAssistant through several representative case studies and a set of evaluation tasks. By lowering technical hurdles, PhenoAssistant underscores the promise of AI-driven methodologies to democratising AI adoption in plant biology.

  PublisherOA PDFDOI

• Hands-free Photosynthesis: Autonomous Leaf-Level Multi-Chamber Gas Exchange System

  University of Essex · 2026-04-27

  datasetOpen accessSenior author

  This is the data associated with with the above paper "Hands-free Photosynthesis: Autonomous Leaf-Level Multi-Chamber Gas Exchange System" comprising of data for figures and supplementary figures. Excel files contain leaf level gas exchange measurements collected from from LI-COR instrument and a novel automated photosynthesis system and whole plant transpiration data from a PlantArray system on sugarcane and cowpea, collected at The University of Illinois. Data collected in 2025.

  PublisherDOI

• What Is the Limit of Vertical Farming Productivity?

  Food and Energy Security · 2025-03-01 · 11 citations

  articleOpen access

  ABSTRACT With the possibility of co‐optimizing all growth factors in vertical farming, such systems could contribute to future food supply, but the potential productivity is unknown. Analyzing 171 publications with 1403 data points across 10 crop categories from controlled‐environment experiments revealed major productivity variation among and within crop species. Potato produced the most edible dry mass of 33 g m −2 day −1 , 28 times more per layer than open‐field cultivation. High planting density crops generally showed a high productivity, while crops with longer life cycles were less productive considering time and space. The limits of productivity, defined as the points at which optimizing growth factors return no further benefit, remain uncertain. Uncovering this limit requires systematic, standardized, and scalable controlled‐environment experiments across crop types.

  PublisherOA PDFDOI

• <scp>DNA</scp> methylation contributes to plant acclimation to naturally fluctuating light

  New Phytologist · 2025-09-20 · 2 citations

  articleOpen accessSenior authorCorresponding

  Plants in the natural environment experience continuous dynamic changes in light intensity. Here, we exposed Arabidopsis thaliana plants to naturally fluctuating light (FL) regimes alongside traditional square light (SQ) regimes such as those often found in control environment growth chambers. The physiological response was highly consistent across experiments in sibling plants, indicating the possibility of an epigenetic mechanism, leading us to investigate differences in DNA methylation. Our results identified a large number of changes in DNA methylation patterns between FL-acclimated plants and SQ-acclimated plants, demonstrating that natural fluctuations in light impact plant epigenetic mechanisms. Most importantly, there are more differences in DNA methylation patterns between different light pattern regimes than between different light intensities. These differences in DNA methylation were accompanied by significant changes in gene expression, some of which correlated with altered DNA methylation. One of these genes, MCCA, was found to significantly impact photosynthetic efficiency when knocked out. Thousands of transposable element (TE) copies were differentially methylated between light regimes. Interestingly, up to 30% of these TEs are linked to nearby differentially expressed genes. Our data suggest DNA methylation plays a role in acclimation to natural light, which may directly regulate gene expression and impact TE activation.

  PublisherDOI

• Soil Moisture and Growth Rates During Peak Yield Accumulation of Cassava Genotypes for Drought and Full Irrigation Conditions

  Environments · 2025-11-06 · 1 citations

  articleOpen access

  Climate change causes unpredictable weather patterns, leading to more frequent and severe droughts. Investigating the effects of drought and irrigation on soil water status and the performance of various cassava genotypes can provide valuable insights for mitigating drought through designing appropriate genotypes and water management strategies. The objective of this research was to evaluate soil moisture, growth rates, and final yields (total dry weight, storage root dry weight, harvest index and starch yield) of six cassava genotypes cultivated under drought conditions during the late growth phase, as well as under full irrigation. The study utilized a split-plot randomized complete block design with four replications, conducted over two growing seasons (2022/2023 and 2023/2024). The main plots were assigned as two water regimes to prevent water movement between plots: full irrigation and drought treatments. The subplot consisted of six cassava genotypes. Measurements included soil properties before planting, weather data, soil moisture content, relative water content (RWC) in cassava leaves, and several growth rates: leaf growth rate (LGR), stem growth rate (SGR), storage root growth rate (SRGR), crop growth rate (CGR), relative growth rate (RGR), as well as final yields. The results revealed that low soil moisture contents for drought treatment led to variation in RWC, growth, and yield among cassava genotypes. Variations in soil and weather conditions between the 2022/2023 and 2023/2024 growing seasons resulted in differences in the performance of the genotypes. Kasetsart 50 (2022/2023) and CMR38–125–77 (2023/2024) were top performers under late drought stress regarding storage root dry weight and starch yield, showing vigorous recovery upon re-watering, evidenced by their significant increase in LGR (between 240 and 270 DAP) and their high RGR (240–360 DAP). Rayong 9 (2023/2024) demonstrated strong performance in both during the drought period (180–240 DAP), efficiently allocating resources under water scarcity, with SRGR and starch yield reduced by 26.4% and 9.5%, respectively, compared to full irrigation. These cassava genotypes are valuable genetic resources for cassava cultivation and can be used as parental material in breeding programs aimed at improving drought tolerance.

  PublisherOA PDFDOI

• Guard cell‐specific glycine decarboxylase manipulation affects Arabidopsis photosynthesis, growth and stomatal behavior

  New Phytologist · 2025-04-11 · 9 citations

  articleOpen access

  Summary Photorespiration is a mandatory metabolic repair shunt of carbon fixation by the Calvin–Benson cycle in oxygenic phototrophs. Its extent depends mainly on the CO 2 : O 2 ratio in chloroplasts, which is regulated via stomatal movements. Despite a comprehensive understanding of the role of photorespiration in mesophyll cells, its role in guard cells (GC) is unknown. Therefore, a key enzyme of photorespiration, glycine decarboxylase (GDC), was specifically manipulated by varying glycine decarboxylase H‐protein (GDC‐H) expression in Arabidopsis GC. Multiple approaches were used to analyze the transgenic lines growth, their gas exchange and Chl fluorescence, alongside metabolomics and microscopic approaches. We observed a positive correlation of GC GDC‐H expression with growth, photosynthesis and carbohydrate biosynthesis, suggesting photorespiration is involved in stomatal regulation. Gas exchange measurements support this view, as optimized GC photorespiration improved plant acclimation toward conditions requiring a high photorespiratory capacity. Microscopic analysis revealed that altered photorespiratory flux also affected GC starch accumulation patterns, eventually serving as an underlying mechanism for altered stomatal behavior. Collectively, our data suggest photorespiration is involved in the regulatory circuit that coordinates stomatal movements with CO 2 availability. Thus, the manipulation of photorespiration in GC has the potential to engineer crops maintaining growth and photosynthesis under future climates.

  PublisherOA PDFDOI

• Extensive photophysiological variation in wild barley is linked to environmental origin

  New Phytologist · 2025-11-11

  articleOpen access

  Summary Intraspecific variation between crop wild relatives (CWRs) represents a source of untapped genetic diversity for crop improvement. At the same time, improving photosynthesis in crops has the potential to enhance yield. Thus, exploring variation for photophysiology within CWRs is an important, yet underexplored, research area. We describe a common garden experiment where 320 wild barley accessions were grown across two seasons. A photophysiology phenotyping pipeline was employed to quantify &gt; 30 traits within this diversity panel. Population genetics, genome‐wide association analyses (GWAS) and deep phenotyping were performed to address local adaptation hypotheses. Heritable variation was detected across this photophysiological spectrum, with genotype‐by‐environment (G × E) interactions being prevalent. Evidence for local adaptation was observed in the form of subpopulation differences, signals of selection and allele frequency variation associated with markers identified via GWAS. Phenotyping of representative accessions across distinct water availabilities highlighted a role for stomatal conductance ( g s ) in adaptation to dry environments. We identified substantial variation in key photosynthesis‐associated traits in a CWR closely related to barley, an economically important crop species. Our results demonstrate that this variation is partially due to local adaptation, where plasticity in g s appears important for maintaining photosynthesis and biomass accumulation in water‐restricted conditions.

  PublisherOA PDFDOI

• The recovery of photosynthetic rate is prolonged in red raspberry following a rootzone water deficit stress

  Acta Horticulturae · 2025-09-01

  article
  PublisherDOI

• Unravelling the physiological and anatomical basis of divergent adaptations in cultivated and wild tomatoes

  Journal of Experimental Botany · 2025-08-30 · 1 citations

  articleOpen accessSenior author

  Distinct physiological and anatomical traits can lead to substantial variation in photosynthetic efficiency among plant varieties, which may, in turn, impact agronomically important traits. We conducted a comprehensive comparative analysis of leaf physiology, anatomy, and biochemistry in Solanum lycopersicum (LEA), a modern inbred variety suited for the processing industry, and Solanum pennellii (Lost, accession LA5240), a drought-tolerant, green-fruited wild species, to investigate differences in photosynthetic performance and stomatal physiology. Lost exhibited higher photosynthetic capacity due to both biochemical and anatomical features. Chlorophyll fluorescence revealed that photosynthesis operates at a higher rate in Lost, due to greater electron sink capacity and efficient electron flow through the photosystems. Lost also showed higher Rubisco content as well as greater chlorophyll a/b ratio and total soluble protein levels than LEA, demonstrating investments in carbon capture relative to light harvesting to support superior photosynthetic performance at higher light intensities. Equal stomatal numbers on the abaxial and adaxial surface for Lost supported its greater leaf thickness and higher photosynthetic capacity, whilst LEA's greater stomatal density on the abaxial surface is typical of commercial broadleaf crops. Grafting experiments demonstrated that LEA scions grafted onto Lost rootstocks displayed improved photosynthesis compared with non-grafted LEA and LEA self-grafted plants, demonstrating successfully transferred enhanced photosynthetic traits from rootstock of Lost to LEA scions. Our study highlights the photosynthetic advantages of Lost and suggests avenues for enhancing tomato productivity through trait transfer.

  PublisherOA PDFDOI

• Crops under stress: can we mitigate the impacts of climate change on agriculture and launch the ‘Resilience Revolution’?

  Philosophical Transactions of the Royal Society B Biological Sciences · 2025-05-29 · 16 citations

  articleOpen accessSenior author

  Climate change is altering our environment, subjecting multiple agroecosystems worldwide to an increased frequency and intensity of abiotic stress conditions such as heat, drought, flooding, salinity, cold and/or their potential combinations. These stresses impact plant growth, yield and survival, causing losses of billions of dollars to agricultural productivity, and in extreme cases they lead to famine, migration and even wars. As the rate of change in our environment has dramatically accelerated in recent years, more research is urgently needed to discover and develop new ways and tools to increase the resilience of crops to different stress conditions. In this theme issue, new studies addressing the molecular, metabolic, and physiological responses of crops and other plants to abiotic stress challenges are discussed, as well as the potential to exploit these mechanisms in biotechnological applications aimed at preserving and/or increasing crop yield under our changing climate conditions.This article is part of the theme issue 'Crops under stress: can we mitigate the impacts of climate change on agriculture and launch the 'Resilience Revolution'?'

  PublisherDOI

Frequent coauthors

• Christine A. Raines

  University of Essex

  48 shared

• Andrew J. Simkin

  University of Essex

  38 shared

• Steven M. Driever

  Wageningen University & Research

  30 shared

• Silvère Vialet‐Chabrand

  Graduate School Experimental Plant Sciences

  30 shared

• M. A. J. Parry

  Lancaster University

  27 shared

• James Morison

  Forest Research

  25 shared

• Stuart J. Fisk

  University of Essex

  24 shared

• Huw Jones

  Aberystwyth University

  22 shared

Education

• PhD

  University of Dundee Biological Sciences

  1997