Plant Health Research Articles

Cytochrome GmGLY1 is Involved in the Biosynthesis of Glycitein in Soybean.

Isoflavones, the major secondary metabolites of interest due to their benefits to both human and plant health, are exclusively produced by legumes. In this study, we profiled the isoflavone content in dry seeds from 211 soybean [Glycine max (L.) Merr.] accessions grown across five environments. Broad and discernible phenotypic variations were observed among accessions, regions, and years of growth. Twenty-six single-nucleotide polymorphisms (SNPs) associated with the sum of glycitein (GLE), glycitin (GL), 6″-O-acetylglycitin (AGL), and 6″-O-malonylglycitin (MGL) contents were detected in multiple environments via a genome-wide association study (GWAS). These SNPs were located on chromosome 11 (8,148,438 bp to 8,296,956 bp, renamed qGly11-01). Glyma.11g108300 (GmGLY1), a gene that encodes a P450 family protein, was identified via sequence variation analysis, functional annotation, weighted gene coexpression network analysis (WGCNA), and expression profile analysis of candidate gene, and hairy roots transformation in soybean. Overexpression of GmGLY1 increased the glycitein content (GLC) in soybean hairy roots and transgenic seeds, while CRISPR/Cas9-generated mutants exhibited decreased GLC and increased daidzein content (DAC). Haplotype analysis revealed that GmGLY1 allelic variations significantly affect the GLC accumulation. These findings enhance our understanding of genes influencing GLC in soybean and may guide breeding for lines with high and stable GLC.

Boron Impact on Maize Growth and Yield: A Review

Maize (Zea mays L.) is a vital crop, contributing significantly—at least 30%—to global dietary energy intake and biofuels and ethanol production. This review article delves into the dynamic interplay between boron (B) and maize growth, yield, and agricultural sustainability. Boron, a crucial micronutrient, is pivotal in essential physiological processes such as root development, leaf expansion, and cob formation. These processes are fundamental for ensuring the vigour and productivity of maize crops. Conversely, boron deficiency manifests as thinner leaves with reduced chlorophyll content, compromising plant health, and hindering yield potential. Maintaining adequate boron levels, particularly during reproductive stages, is critical for mitigating the risk of abnormal ears and maximizing the quantity and quality of maize production. Emerging research underscores the significance of foliar boron application at various growth stages of maize, which stimulates growth, facilitates cell wall development, and increases leaf area. This translates to improved light interception and photosynthetic efficiency, ultimately contributing to increased plant vigour and biomass accumulation. Furthermore, exploring innovative approaches for sustainable boron management is crucial. This includes precision fertilization techniques and biofortification strategies to ensure optimal maize production while minimizing environmental impacts. By gaining a deeper understanding of the complex relationship between boron and maize, farmers can develop customized fertilization plans that utilize strategic foliar boron application. This approach unlocks maize's full yield potential and contributes to sustainable agricultural practices, supporting global food security.

A carbon dot toolbox for managing biotic and abiotic stresses in crop production systems

AbstractThe productivity of global crop production is under threat caused by various biotic and abiotic adverse conditions, such as plant diseases and pests, which are responsible for 20%–40% of global crop losses estimated at a value of USD 220 billion, and can be further exacerbated by climate change. Agricultural industries are calling for game‐changer technologies to enable productive and sustainable farming. Carbon dots (C‐dots) are carbon‐based nanoparticles, smaller than 50 nm, exhibiting unique opto‐electro‐properties. They have been shown to have positive impact on managing diverse biotic and abiotic stresses faced by the crops. Owing to their versatile carbon chemistry, the surface functionalities of C‐dots can be readily tuned to regulate plant physiological processes. This review is focussed on establishing the correlations between the physiochemical properties of C‐dots and their impacts on plants growth and health. The summary of the literature demonstrates that C‐dots hold great promise in improving plant tolerance to heat, drought, toxic chemicals, and invading pathogens.image

Impact of Soil-Applied Thyme Oil on Strawberry Yield and Disease Abundance

ABSTRACT Strawberry growers across the United States are looking for sustainable alternatives to conventional pesticides for management of soil-borne or crown-rot causing pathogens, such as plant-extracts like thyme oil. The objectives of this study were to determine the impact of soil-applied thyme oil fungicides on strawberry plant health, yield, sweetness, and foliar disease, and on the assemblage of soil microbial communities in strawberry plasticulture systems. In 2021 and 2022 the interaction of three soil-applied fungicides and three foliar fungicide programs were explored. Thyme oil was not found to improve strawberry plant growth or yield when compared to strawberries in the control. However, plants treated with mefenoxam exhibited an average winter crown weight of 2.11 g, significantly lower than control and thyme oil treatments at 3.14 g and 3.16 g, respectively. This translated into a significant yield loss where mefenoxam treated plants exhibited lowered yields at 416.04 g of fruit per plant compared to 523.57 g and 521.53 g per plant in the control and thyme oil treatments, respectively. A high incidence of foliar and fruit diseases was present; however, no interaction of soil and foliar fungicide treatments were observed for yield or fruit sweetness. Minimal root protection from pathogens was observed for all treatments and Fusarium, Pythium and Phytophthora fungi were regularly observed. Mefenoxam was observed to increase the recovery of oomycetes, which may cause Pythium and Phytophthora. No benefit from thyme oil was observed at our site and its addition as a soil fungicide would likely not benefit most growers.

Impact of Heavy Metal Contamination on Soil and Crop Ecosystem with Advanced Techniques to Mitigate Them

Heavy metal pollution in soils has become widespread globally due to both natural processes and human activities. Geologic and anthropogenic activities, such as mining, industrial processes, and agricultural practices, significantly contribute to heavy metal accumulation in soil, posing threats to both plant and animal health. These metals endure in the environment and build up in organisms because they resist breakdown or metabolism. They enter the food chain via primary producers and move up as higher trophic levels consume them. This contamination adversely affects the overall human health, plant growth, performance, and yield and also impacts the soil properties. To minimize this effect of heavy metal toxicity, bioremediation emerges as a highly effective method for treating such polluted soils, often conducted in situ, making it suitable for crop establishment or reestablishment. Bioremediation encompasses various techniques like bioventing, biostimulation, air sparging, natural attenuation, phytoremediation, vermistabilization, rhizofiltration, biosorption etc. Both microorganisms and plants play crucial roles in bioremediation, with the combined approach ensuring more efficient cleanup. However, the success of this method depends significantly on the specific species involved. Traditional physical and chemical remediation methods are often costly and fail to restore soil suitability for plant growth. In contrast, bioremediation offers a more environmentally friendly and economically viable solution, leveraging natural processes to encourage plant growth on contaminated soils.

Mitigating Emerging and Reemerging Diseases of Fruit and Vegetable Crops in a Changing Climate.

Fruit and vegetable crops are important sources of nutrition and income globally. Producing these high-value crops requires significant investment of often scarce resources, and, therefore, the risks associated with climate change and accompanying disease pressures are especially important. Climate change influences the occurrence and pressure of plant diseases, enabling new pathogens to emerge and old enemies to reemerge. Specific environmental changes attributed to climate change, particularly temperature fluctuations and intense rainfall events, greatly alter fruit and vegetable disease incidence and severity. In turn, fruit and vegetable microbiomes, and subsequently overall plant health, are also affected by climate change. Changing disease pressures cause growers and researchers to reassess disease management and climate change adaptation strategies. Approaches such as climate smart integrated pest management, smart sprayer technology, protected culture cultivation, advanced diagnostics, and new soilborne disease management strategies are providing new tools for specialty crops growers. Researchers and educators need to work closely with growers to establish fruit and vegetable production systems that are resilient and responsive to changing climates. This review explores the effects of climate change on specialty food crops, pathogens, insect vectors, and pathosystems, as well as adaptations needed to ensure optimal plant health and environmental and economic sustainability.

Exogenous of different elicitors: proline and ornithine on Sansevieria trifasciata under particulate matter (PM) and volatile organic compounds (VOC).

Phytoremediation has become famous for removing particulate matter (PM) and volatile organic compounds (VOC) in situ. Plants for removing PM and VOC were associated with botanical biofilters to attract pollution to the plant. On the other hand, persistent pollution exposure can lower plant health and phytoremediation effectiveness; therefore, improving plant tolerance against stress is necessary. Various elicitors can enhance plant tolerance to certain stressors. This study aims to investigate different elicitors to maintain plant health and improve the use of plants in phytoremediation for PM and VOC pollution. This experiment used Sansevieria trifasciata hort. ex Prain under PM and VOC stress. Exogenous elicitors, such as proline, ornithine, and a commercial product, were applied to the leaf parts before exposure to PM and VOC stress. The initial concentrations of PM1, PM2.5, and PM10 were 300-350, 350-450, and 400-500µgm-3, respectively, while the VOC concentration was 2.5-3.0mgm-3. The plant was stressed for 7days. The result indicated that ornithine 10mM is vital in improving plant tolerance and inducing antioxidant enzymes against PM and VOC, while proline 50mM and a commercial product could not reduce plant stress. This study suggests that ornithine might be an important metabolite to improve plant tolerance to PM and VOC.

N-acetylcysteine absorption and its potential dual effect improve fitness and fruit yield in Xylella fastidiosa infected plants.

Xylella fastidiosa is a multi-host bacterium that can be detected in hundreds of plant species including several crops. Diseases caused by X. fastidiosa are considered a threat to global food production. The primary method for managing diseases caused by X. fastidiosa involves using insecticides to control the vector. Hence, it is necessary to adopt new and sustainable disease management technologies to control not only the insect but also the bacteria and plant health. We demonstrated that N-acetylcysteine (NAC), a low-cost cysteine analogue, is a sustainable molecule that can be used in agriculture to decrease the damage caused by X. fastidiosa and improve plant health. Using 15N-NAC we proved that this analogue was absorbed by the roots and transported to different parts of the plant. Inside the plant, NAC reduced the bacterial population by 60-fold and the number of xylem vessels blocked by bacterial biofilms. This reflected in a recovery of 0.28-fold of the daily sap flow compared to health plants. In addition, NAC-treated citrus variegated chlorosis (CVC) plants decreased the oxidative stress by improving the activity of detoxifying enzymes. Moreover, the use of NAC in field conditions positively contributed to the increase in fruit yield of CVC-diseased plants. Our research not only advances the understanding of NAC absorption in plants, but also indicates its dual effect as an antimicrobial and antioxidant molecule. This, in turn, negatively affects bacterial survival while improving plant health by decreasing oxidative stress. Overall, the positive field-based evidence supports the viability of NAC as a sustainable agricultural application. © 2024 Society of Chemical Industry.

Detection and Classification of Wilting in Soybean Crop using Cutting-edge Deep Learning Techniques

Background: This paper employs deep learning in the classification of soybean wilting, a plant health indicator affected by external pressures, using a Convolutional Neural Network (CNN) with a pre-trained model. It highlights the promise of deep learning in agriculture by examining the relevance of wilting, evolution in the agricultural sector and applications in crop wellness monitoring. Methods: A CNN is used in the study to classify soybean withering, with special attention to the VGG16 pre-trained model. Deep learning’s ability to interpret complex data patterns is harnessed for intelligent and accurate wilting detection. A smart detection system tailored for soybean wilting is developed, incorporating recent advancements and addressing associated challenges. Result: The CNN model, notably VGG16, achieves 76% overall accuracy in distinguishing healthy and wilted soybean leaves, signifying a transformative shift in soybean crop health management. The approach offers a precise, efficient and sustainable solution supported by state-of-the-art CNN technology, advancing soybean cultivation practices.

Commodity risk assessment of Tilia cordata and Tilia platyphyllos plants from the UK.

The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by plants of Tilia cordata and T. platyphyllos imported from the United Kingdom (UK) as: (a) bundles of budwood/graftwood; (b) 1- to 2-year-old whips, seedlings or transplants; (c) bundles of 1- to 2-year-old cell grown plants; (d) 1- to 7-year-old bare root single plants; and (e) up to 25-year-old single plants in pots, taking into account the available scientific information provided by the UK. A list of pests potentially associated with the commodities was compiled. The relevance of any pest was assessed based on evidence following defined criteria. None of the pests on the list fulfilled all relevant criteria and therefore none were selected for further evaluation. As a result, risk mitigation measures proposed in the technical dossier from the UK were listed, but not further evaluated.

Depletion of protective microbiota promotes the incidence of fruit disease.

Plant-associated microbiomes play important roles in plant health and productivity. However, despite fruits being directly linked to plant productivity, little is known about the microbiomes of fruits and their potential association with fruit health. Here, by integrating 16S rRNA gene, ITS high-throughput sequencing data and microbiological culturable approaches, we reported that roots and fruits (pods) of peanut, a typical plant that bears fruits underground, recruit different bacterial and fungal communities independently of cropping conditions, and that the incidence of pod disease under monocropping conditions is attributed to the depletion of Bacillus genus and enrichment of Aspergillus genus in geocarposphere. On this basis, we constructed a synthetic community (SynCom) consisting of three Bacillus strains from geocarposphere soil under rotation conditions with high culturable abundance. Comparative transcriptome, microbiome profiling and plant phytohormone signaling analysis reveal that the SynCom exhibited more effective Aspergillus growth inhibition and pod disease control than individual strain, which was underpinned by a combination of molecular mechanisms related to fungal cell proliferation interference, mycotoxins biosynthesis impairment and jasmonic acid-mediated plant immunity activation. Overall, our results reveal the filter effect of plant organs on the microbiome, and that depletion of key protective microbial community promotes the fruit disease incidence.

A Comparative Analysis of Microbial Communities in the Rhizosphere Soil and Plant Roots of Healthy and Diseased Yuanyang Nanqi (Panax vietnamensis) with Root Rot

Microbial communities are not only an important indicator of soil status but also a determinant of plant nutrition and health levels. Loss of microbial community ecosystem control can directly lead to microbial disease occurrence. During the process of Yuanyang Nanqi wild imitation planting, root rot diseases frequently occur, seriously affecting their yield and quality. Via amplicon sequencing, this study mainly compared the microbial community composition between the rhizosphere soil and roots of healthy and diseased Yuanyang Nanqi with root rot. The α-diversity showed that the microbial community diversity and abundance in the roots of diseased Yuanyang Nanqi were much lower than those of those in healthy specimens, while no significant difference was found in the rhizosphere soil. The β－diversity showed that the bacterial community in the Gejiu region and the fungal community in the Honghe region were significantly different from those in other regions. The species relative abundance map showed that there was no obvious difference in microbial community composition between the rhizosphere soil and roots of healthy and diseased Nanqi, but in diseased specimens with root rot, the proportions of Pseudomonas and Fusarium increased. Based on a functional prediction analysis of FUNGuild, the results showed that the Nanqi roots were mainly pathological saprophytic type and that their rhizosphere soil was mainly saprophytic type. The microorganisms in the roots of Yuanyang Nanqi tubers with root rot were also isolated and identified through the use of the culture method. The possible pathogenic strains were tested via anti－inoculation, and Fusarium oxysporum was identified as one of the main pathogenic fungi of Nanqi root rot, which was consistent with the amplicon sequencing results. These results will help us understand the change trend of microbial communities in healthy and diseased plants and analyze the pathogens involved, the pathogenesis, and the beneficial microorganisms, which would provide a theoretical basis for effective biological control.

Utility of decision tools for assessing plant health risks from management strategies in natural environments.

Increased imports of plants and timber through global trade networks provide frequent opportunities for the introduction of novel plant pathogens that can cross-over from commercial to natural environments, threatening native species and ecosystem functioning. Prevention or management of such outbreaks relies on a diversity of cross-sectoral stakeholders acting along the invasion pathway. Yet, guidelines are often only produced for a small number of stakeholders, missing opportunities to consider ways to control outbreaks in other parts of the pathway. We used the infection of common juniper with the invasive pathogen Phytophthora austrocedri as a case study to explore the utility of decision tools for managing outbreaks of plant pathogens in the wider environment. We invited stakeholders who manage or monitor juniper populations or supply plants or management advice to participate in a survey exploring their awareness of, and ability to use, an existing decision tree produced by a coalition of statutory agencies augmented with new distribution maps designed by the authors. Awareness of the decision tree was low across all stakeholder groups including those planting juniper for restoration purposes. Stakeholders requested that decision tools contain greater detail about environmental conditions that increase host vulnerability to the pathogen, and clearer examples of when management practices implicated in pathogen introduction or spread should not be adopted. The results demonstrate the need to set clear objectives for the purpose of decision tools and to frame and co-produce them with many different stakeholders, including overlooked groups, such as growers and advisory agents, to improve management of pathogens in the wider environment.

Endophytic Fungi Residing within Cornus florida L. in Mid-Tennessee: Phylogenetic Diversity, Enzymatic Properties, and Potential Role in Plant Health

Endophytic fungi that reside internally in healthy, asymptomatic plants often benefit their hosts by promoting plant growth and/or providing plant protection against abiotic and biotic stresses. However, only a small fraction of the estimated 1.5 million fungal endophytes have been identified. In this study, a total of 369 isolates of fungal endophytes in 59 distinct taxa were isolated from stem samples of Cornus florida (flowering dogwood). All isolates belonged to species of phyla Ascomycota and Basidiomycota distributed across five orders and 11 genera. Isolates belonging to the same family clustered together in a phylogenetic tree generated from a cluster analysis using MEGA 7 software. Diversity indices of the fungi revealed a rich and diverse community that included several species associated with leaf spots, blight, cankers, and/or dieback diseases. Pathogenicity tests confirmed 16 fungal endophytes as C. florida pathogens, including some well-known destructive pathogens Botryosphaera dothidea, Colletotrichum acutatum, and C. gleosporoides. Isolates of the fungal endophytes possess the capacity to produce extracellular hydrolytic enzymes (cellulase, amylase, pectinase, laccase, chitinase, and protease) that are known to function in tissue penetration, plant colonization, nutrient acquisition, and disease suppression in both plant pathogens and endophytes These results support the interchangeable pathogenic–endophytic roles for some taxa.

IOT Based Smart Plant Monitoring System

Abstract: The IoT-based Smart Plant Monitoring System represents a transformative approach to modern agriculture by leveraging the power of the Internet of Things (IoT) to enhance the monitoring and management of plants in agricultural settings. This system integrates advanced sensor technologies, wireless communication, and data analytics to provide real-time insights into the health and environmental conditions of plants, thereby optimizing resource utilization and improving overall crop yield. The key components of the proposed system include a network of sensors strategically placed within the agricultural field to capture vital data related to soil moisture, temperature, humidity, light intensity, and nutrient levels. These sensors are connected through IoT-enabled devices, forming a cohesive network that continuously collects and transmits data to a centralized cloud-based platform. The cloud platform acts as a repository for the acquired data, where advanced analytics algorithms process the information in real-time

Disease-induced changes in bacterial and fungal communities from plant below- and aboveground compartments

The plant microbes are an integral part of the host and play fundamental roles in plant growth and health. There is evidence indicating that plants have the ability to attract beneficial microorganisms through their roots in order to defend against pathogens. However, the mechanisms of plant microbial community assembly from below- to aboveground compartments under pathogen infection remain unclear. In this study, we investigated the bacterial and fungal communities in bulk soil, rhizosphere soil, root, stem, and leaf of both healthy and infected (Potato virus Y disease, PVY) plants. The results indicated that bacterial and fungal communities showed different recruitment strategies in plant organs. The number and abundance of shared bacterial ASVs between bulk and rhizosphere soils decreased with ascending migration from below- to aboveground compartments, while the number and abundance of fungal ASVs showed no obvious changes. Field type, plant compartments, and PVY infection all affected the diversity and structures of microbial community, with stronger effects observed in the bacterial community than the fungal community. Furthermore, PVY infection, rhizosphere soil pH, and water content (WC) contributed more to the assembly of the bacterial community than the fungal community. The analysis of microbial networks revealed that the bacterial communities were more sensitive to PVY infection than the fungal communities, as evidenced by the lower network stability of the bacterial community, which was characterized by a higher proportion of positive edges. PVY infection further increased the bacterial network stability and decreased the fungal network stability. These findings advance our understanding of how microbes respond to pathogen infections and provide a rationale and theoretical basis for biocontrol technology in promoting sustainable agriculture.Key points• Different recruitment strategies between plant bacterial and fungal communities.• Bacterial community was more sensitive to PVY infection than fungal community.• pH and WC drove the microbial community assembly under PVY infection.

AI-Powered Disease Detection and Growth Monitoring System Using IoT for Improved Tomato Yield

Abstract: This project introduces an advanced AI- powered disease detection and growth monitoring system designed specifically for enhancing tomato yield. With Internet of Things (IoT) technology, the system integrates Raspberry Pi as the central processing unit with temperature and humidity sensors for environmental monitoring. AI algorithms are used to predict tomato ripening stages and detect diseases, to ensure proactive management of plant health. If a disease is identified, the system provides the solutions to control its impact, thereby enhancing yield and quality. The captured data is analysed and results are displayed on a user-friendly webpage accessible to farmers, enabling informed decision-making and improved agricultural practices. This innovative approach combines technology with agricultural expertise, offering a solution to the challenges faced by tomato farmers and contributing to sustainable tomato production. Keywords: Image Recognition, Disease Detection

Monitoring and Controlling of Greenhouse

Abstract: The potential for revolutionizing crop production practices has drawn significant attention to the monitoring and management of greenhouse settings. With the help of greenhouses, plants may grow in a controlled environment with the right amount of light, heat, humidity, and soil moisture. However, manual monitoring and intervention—which may be timeconsuming, laLbor-intensive, and prone to human error are frequently used in traditional greenhouse management techniques. The design, implementation, and assessment of a greenhouse monitoring and controlling system built around the ESP32 controller are proposed in this research paper. In order to gather environmental data—such as temperature, humidity, soil moisture, and light intensity—that is essential for determining plant health and maximizing growth conditions, the system incorporates sensors. Farmers may remotely get real-time insights into their greenhouse operations by transmitting the acquired data to a cloud platform or central monitoring station using the ESP32's networking features. the incorporation of ESP32 controllers into greenhouse management is a noteworthy technical development that has the potential to completely transform current agricultural methods. ESP32-based systems give farmers a strong tool for maximizing agricultural productivity while reducing resource inputs and environmental effects by providing real-time monitoring and precise control of environmental conditions

Re-Envisioning the Plant Disease Triangle by Integration of Host Microbiota and a Pivot in Focus to Health Outcomes.

The disease triangle is a structurally simple but conceptually rich model that is used in plant pathology and other fields of study to explain infectious disease as an outcome of the three-way relationship between a host, a pathogen, and their environment. It also serves as a guide for finding solutions to treat, predict, and prevent such diseases. With the omics-driven, evidence-based realization that the abundance and activity of a pathogen are impacted by proximity to and interaction with a diverse multitude of other microorganisms colonizing the same host, the disease triangle evolved into a tetrahedron shape, which features an added fourth dimension representing the host-associated microbiota. Another variant of the disease triangle emerged from the recently formulated pathobiome paradigm, which deviates from the classical "one pathogen" etiology of infectious disease in favor of a scenario in which disease represents a conditional outcome of complex interactions between and among a host, its microbiota (including microbes with pathogenic potential), and the environment. The result is a version of the original disease triangle where "pathogen" is substituted with "microbiota." Here, as part of a careful and concise review of the origin, history, and usage of the disease triangle, I propose a next step in its evolution, which is to replace the word "disease" in the center of the host-microbiota-environment triad with the word "health." This triangle highlights health as a desirable outcome (rather than disease as an unwanted state) and as an emergent property of host-microbiota-environment interactions. Applied to the discipline of plant pathology, the health triangle offers an expanded range of targets and approaches for the diagnosis, prediction, restoration, and maintenance of plant health outcomes. Its applications are not restricted to infectious diseases only, and its underlying framework is more inclusive of all microbial contributions to plant well-being, including those by mycorrhizal fungi and nitrogen-fixing bacteria, for which there never was a proper place in the plant disease triangle. The plant health triangle also may have an edge as an education and communication tool to convey and stress the importance of healthy plants and their associated microbiota to a broader public and stakeholdership.

Horizontal gene transfer in plant microbiomes: integrons as hotspots for cross-species gene exchange

Plant microbiomes play important roles in plant health and fitness. Bacterial horizontal gene transfer (HGT) can influence plant health outcomes, driving the spread of both plant growth-promoting and phytopathogenic traits. However, community dynamics, including the range of genetic elements and bacteria involved in this process are still poorly understood. Integrons are genetic elements recently shown to be abundant in plant microbiomes, and are associated with HGT across broad phylogenetic boundaries. They facilitate the spread of gene cassettes, small mobile elements that collectively confer a diverse suite of adaptive functions. Here, we analysed 5,565 plant-associated bacterial genomes to investigate the prevalence and functional diversity of integrons in this niche. We found that integrons are particularly abundant in the genomes of Pseudomonadales, Burkholderiales, and Xanthomonadales. In total, we detected nearly 9,000 gene cassettes, and found that many could be involved in plant growth promotion or phytopathogenicity, suggesting that integrons might play a role in bacterial mutualistic or pathogenic lifestyles. The rhizosphere was enriched in cassettes involved in the transport and metabolism of diverse substrates, suggesting that they may aid in adaptation to this environment, which is rich in root exudates. We also found that integrons facilitate cross-species HGT, which is particularly enhanced in the phyllosphere. This finding may provide an ideal opportunity to promote plant growth by fostering the spread of genes cassettes relevant to leaf health. Together, our findings suggest that integrons are important elements in plant microbiomes that drive HGT, and have the potential to facilitate plant host adaptation.