Exogenous methyl jasmonate enhanced kenaf (Hibiscus cannabinus) tolerance against lead (Pb) toxicity by improving antioxidant capacity and osmoregulators

In this study, the effects of exogenous methyl jasmonate (MeJA) on metal uptake and its ability to attenuate metal toxicity in kenaf plants under Pb stress were investigated. The experiment was conducted with five different MeJA concentrations (0, 40, 80, 160, and 320 μM) as a foilar application to kenaf plants exposed to 200 μM Pb stress. The results revealed that pretreatmen of MeJA significantly increased plant dry weight, plant height, and root architecture at all concentrations tested, with the most significant increase at 320 μM. Foliar application of MeJA at 160 μM and 320 μM increased the Pb concentrations in leaves and stems as well as the translocation factor (TF) from root to leaf. However, the bioaccumulation factor in the shoot initially decreased and then increased with increasing MeJA concentration. By increasing enzymatic (SOD, POD, and CAT) and non-enzymatic (AsA and non-protein thiols) antioxidants, MeJA pretreatment decreased lipid peroxidation, O2- and H2O2 accumulation and recovered photosynthetic pigment content under Pb stress. Increased osmolytes (proline, sugar, and starch) and protein content after MeJA pretreatment under Pb stress restore cellular homeostasis and improved kenaf tolerance. Our results suggest that MeJA pretreatment modifies the antioxidant machinery of kenaf and inhibits stress-related processes that cause lipid peroxidation, hence enhancing plant tolerance to Pb stress.

A facultative ectomycorrhizal association is triggered by organic nitrogen

Increasing nitrogen (N) deposition often tends to negatively impact the functions of belowground ectomycorrhizal networks, although the exact molecular mechanisms underlying this trait are still unclear. Here, we assess how the root-associated fungus Clitopilus hobsonii establishes an ectomycorrhiza-like association with its host tree Populus tomentosa and how this interaction is favored by organic N over mineral N. The establishment of a functional symbiosis in the presence of organic N promotes plant growth and the transfer of ¹⁵N from the fungus to above ground plant tissues. Genomic traits and in planta transcriptional signatures suggest that C. hobsonii may have a dual lifestyle with saprotrophic and mutualistic traits. For example, several genes involved in the digestion of cellulose and hemicellulose are highly expressed during the interaction, whereas the expression of multiple copies of pectin-digesting genes is tightly controlled. Conversely, the nutritional mutualism is dampened in the presence of ammonium (NH₄⁺) or nitrate (NO₃^-). Increasing levels of NH₄⁺ led to a higher expression of pectin-digesting genes and a continuous increase in hydrogen peroxide production in roots, whereas the presence of NO₃^- resulted in toxin production. In summary, our results suggest that C. hobsonii is a facultative ectomycorrhizal fungus. Access to various forms of N acts as an on/off switch for mutualism caused by large-scale fungal physiological remodeling. Furthermore, the abundance of pectin-degrading enzymes with distinct expression patterns during functional divergence after exposure to NH₄⁺ or organic N is likely to be central to the transition from parasitism to mutualism.

Long Non-Coding RNAs: New Players in Plants

During the process of growth and development, plants are prone to various biotic and abiotic stresses. They have evolved a variety of strategies to resist the adverse effects of these stresses. lncRNAs (long non-coding RNAs) are a type of less conserved RNA molecules of more than 200 nt (nucleotides) in length. lncRNAs do not code for any protein, but interact with DNA, RNA, and protein to affect transcriptional, posttranscriptional, and epigenetic modulation events. As a new regulatory element, lncRNAs play a critical role in coping with environmental pressure during plant growth and development. This article presents a comprehensive review on the types of plant lncRNAs, the role and mechanism of lncRNAs at different molecular levels, the coordination between lncRNA and miRNA (microRNA) in plant immune responses, the latest research progress of lncRNAs in plant growth and development, and their response to biotic and abiotic stresses. We conclude with a discussion on future direction for the elaboration of the function and mechanism of lncRNAs.

Role of Auxin and Nitrate Signaling in the Development of Root System Architecture

The plant root is an important storage organ that stores indole-3-acetic acid (IAA) from the apical meristem, as well as nitrogen, which is obtained from the external environment. IAA and nitrogen act as signaling molecules that promote root growth to obtain further resources. Fluctuations in the distribution of nitrogen in the soil environment induce plants to develop a set of strategies that effectively improve nitrogen use efficiency. Auxin integrates the information regarding the nitrate status inside and outside the plant body to reasonably distribute resources and sustainably construct the plant root system. In this review, we focus on the main factors involved in the process of nitrate- and auxin-mediated regulation of root structure to better understand how the root system integrates the internal and external information and how this information is utilized to modify the root system architecture.

Gravity Reduced Nitrogen Uptake via the Regulation of Brace Unilateral Root Growth in Maize Intercropping

Water, nutrient, light, and interspecific facilitation regulation of soil physicochemical properties and root morphology modulate nitrogen (N) uptake in cereal and legume intercropping systems. However, maize root morphological plasticity and N uptake capability response to gravity in the intercropping system remains to be determined. In this study, maize was grown under 20 cm (I₂₀), 40 cm (I₄₀), and 60 cm (I₆₀) of narrow row spacing in an intercropping system (maize-soybean strip relay intercropping) and equal row spacing of monoculture (M) in a 2-year field experiment. As a supplementary for the field experiment, maize root barrier and plant inclination experiments were conducted. Plant inclination, brace root morphology, N uptake, indole-3-acetic acid (IAA) level, IAA synthesis genes, and grain yield were assessed. The result showed that the plant inclination increased with decreasing narrow row spacing in intercropping system. Also, the brace unilateral root growth ratio (BURR) increased with increasing plant inclination in intercropping treatments. The plant inclination experiment showed the BURR achieved 94% after inclination at 45°. BURR tended to be positively correlated (p = 0.00) with plant inclination. Thus, gravity (plant inclination) causes brace unilateral root growth. The IAA concentration of stem nodes in the wide row increased with increasing plant inclination, while the IAA accumulation decreased in the narrow row. The Zmvt2 and ZM2G141383 genes (associated with IAA biosynthesis) were highly expressed in a wide row. There was a strong correlation (p = 0.03) between the IAA concentration of wide row and the BURR. Therefore, gravity regulates the IAA level, which affects BURR. In addition, the brace root number, volume, and surface area were decreased when BURR was increased. Subsequently, the leaf N, cob N, and kernel N accumulation were reduced. These organs N and grain yield in I₆₀ were not significantly different as compared to the control treatment. The excessive brace unilateral root growth was not conducive to N uptake and increased yield. Our results suggest that gravity is essential in regulating root morphology plasticity by regulating IAA levels and decreasing N uptake capacity. Furthermore, these results indicate that plant inclination can regulate root phenotype and N uptake of maize and by adjusting the spacing of narrow maize row, we can improve the N uptake and yield of the maize-soybean strip relay-intercropping system.

The role of CLV1, CLV2 and HPAT homologues in the nitrogen-regulation of root development

Plants use a variety of signals to control root development, including in modifying root development in response to nutrient stress. For example, in response to nitrogen (N) stress, plants dramatically modulate root development, including the formation of N-fixing nodules in legumes. Recently, specific CLE peptides and/or receptors important for their perception, including CLV1 and CLV2, have been found to play roles in root development, including in response to N supply. In the legume Medicago truncatula, this response also appears to be influenced by RDN1, a member of the hydroxyproline-O-arabinosyltransferase (HPAT) family which can modify specific CLE peptides. However, it is not known if this signalling pathway plays a central role in root development across species, and in particular root responses to N. In this study, we systematically examined the role of the CLV signalling pathway genes in root development of the legume pea (Pisum sativum) and non-legume tomato (Solanum lycopersicum) using a mutant-based approach. This included a detailed examination of root development in response to N in tomato mutants disrupted in CLV1- or CLV2-like genes or HPAT family member FIN. We found no evidence for a role of these genes in pea seedling root development. Furthermore, the CLV1-like FAB gene did not influence tomato root development, including the root response to N supply. In contrast, both CLV2 and the HPAT gene FIN appear to positively influence root size in tomato but do not mediate root responses to N. These results suggest the function of these genes may vary somewhat in different species, including the N regulation of root architecture.

Combined Transcriptome and Proteome Analysis of Masson Pine (Pinus massoniana Lamb.) Seedling Root in Response to Nitrate and Ammonium Supplementations

Nitrogen (N) is an essential nutrient for plant growth and development. Plant species respond to N fluctuations and N sources, i.e., ammonium or nitrate, differently. Masson pine (Pinus massoniana Lamb.) is one of the pioneer plants in the southern forests of China. It shows better growth when grown in medium containing ammonium as compared to nitrate. In this study, we had grown masson pine seedlings in medium containing ammonium, nitrate, and a mixture of both, and performed comparative transcriptome and proteome analyses to observe the differential signatures. Our transcriptome and proteome resulted in the identification of 1593 and 71 differentially expressed genes and proteins, respectively. Overall, the masson pine roots had better performance when fed with a mixture of ammonium and nitrate. The transcriptomic and proteomics results combined with the root morphological responses suggest that when ammonium is supplied as a sole N-source to masson pine seedlings, the expression of ammonium transporters and other non-specific NH₄⁺-channels increased, resulting in higher NH₄⁺ concentrations. This stimulates lateral roots branching as evidenced from increased number of root tips. We discussed the root performance in association with ethylene responsive transcription factors, WRKYs, and MADS-box transcription factors. The differential analysis data suggest that the adaptability of roots to ammonium is possibly through the promotion of TCA cycle, owing to the higher expression of malate synthase and malate dehydrogenase. Masson pine seedlings managed the increased NH₄⁺ influx by rerouting N resources to asparagine production. Additionally, flavonoid biosynthesis and flavone and flavonol biosynthesis pathways were differentially regulated in response to increased ammonium influx. Finally, changes in the glutathione s-transferase genes suggested the role of glutathione cycle in scavenging the possible stress induced by excess NH₄⁺. These results demonstrate that masson pine shows increased growth when grown under ammonium by increased N assimilation. Furthermore, it can tolerate high NH₄⁺ content by involving asparagine biosynthesis and glutathione cycle.

Two receptor-like protein kinases, MUSTACHES and MUSTACHES-LIKE, regulate lateral root development in Arabidopsis thaliana

Receptor-like protein kinases (RLKs) play key roles in regulating plant growth, development and stress adaptations. There are at least 610 RLKs (including receptor-like cytoplasmic kinases) in Arabidopsis. The functions of the majority of RLKs have not yet been determined. We previously generated promoter::GUS transgenic plants for all leucine-rich repeat (LRR)-RLKs in Arabidopsis and analyzed their expression patterns during various developmental stages. We found the expression of two LRR-RLKs, MUSTACHES (MUS) and MUSTACHES-LIKE (MUL), are overlapped in lateral root primordia. Independent mutants, mus-3 mul-1 and mus-4 mul-2, show a significantly decreased emerged lateral root phenotype. Our analyses indicate that the defects of the double mutant occur mainly at stage I of lateral root development. Exogenous application of auxin can dramatically enhance the transcription of MUS, which is largely dependent on AUXIN RESPONSE FACTOR 7 (ARF7) and ARF19. MUS and MUL are inactive kinases in vitro but are phosphorylated in planta, possibly by an unknown kinase. The kinase activity of MUS is dispensable for its function in lateral root development. Many cell wall related genes are down regulated in mus-3 mul-1. In conclusion, we identified MUS and MUL, two kinase-inactive RLKs, in controlling the early development of lateral root primordia likely via regulating cell wall synthesis and remodeling.

Nitrate and Ammonium Affect the Overall Maize Response to Nitrogen Availability by Triggering Specific and Common Transcriptional Signatures in Roots

Nitrogen (N) is an essential macronutrient for crops. Plants have developed several responses to N fluctuations, thus optimizing the root architecture in response to N availability. Nitrate and ammonium are the main inorganic N forms taken up by plants, and act as both nutrients and signals, affecting gene expression and plant development. In this study, RNA-sequencing was applied to gain comprehensive information on the pathways underlying the response of maize root, pre-treated in an N-deprived solution, to the provision of nitrate or ammonium. The analysis of the transcriptome shows that nitrate and ammonium regulate overlapping and distinct pathways, thus leading to different responses. Ammonium activates the response to stress, while nitrate acts as a negative regulator of transmembrane transport. Both the N-source repress genes related to the cytoskeleton and reactive oxygen species detoxification. Moreover, the presence of ammonium induces the accumulation of anthocyanins, while also reducing biomass and chlorophyll and flavonoids accumulation. Furthermore, the later physiological effects of these nutrients were evaluated through the assessment of shoot and root growth, leaf pigment content and the amino acid concentrations in root and shoot, confirming the existence of common and distinct features in response to the two nitrogen forms.

The long noncoding RNA T5120 regulates nitrate response and assimilation in Arabidopsis

Long noncoding RNAs (lncRNAs) are crucial regulators in many plant biological processes. However, it remains unknown whether lncRNAs can respond to nitrate or function in nitrate regulation. We detected 695 lncRNAs, 480 known and 215 novel, in Arabidopsis seedling roots; six showed altered expression in response to nitrate treatment, among which T5120 showed the highest induction. Overexpression of T5120 in Arabidopsis promoted the response to nitrate, enhanced nitrate assimilation and improved biomass and root development. Biochemical and molecular analyses revealed that NLP7, a master nitrate regulatory transcription factor, directly bound to the nitrate-responsive cis-element (NRE)-like motif of the T5120 promoter and activated T5120 transcription. In addition, T5120 partially restored the nitrate signalling and assimilation phenotypes of nlp7 mutant, suggesting that T5120 is involved in NLP7-mediated nitrate regulation. Interestingly, the expression of T5120 was regulated by the nitrate sensor NRT1.1. Therefore, T5120 is modulated by NLP7 and NRT1.1 to regulate nitrate signalling. Our work reveals a new regulatory mechanism in which lncRNA T5120 functions in nitrate regulation, providing new insights into the nitrate signalling network. Importantly, lncRNA T5120 can promote nitrate assimilation and plant growth to improve nitrogen use efficiency.

A novel function of N-signaling in plants with special reference to Trichoderma interaction influencing plant growth, nitrogen use efficiency, and cross talk with plant hormones

Trichoderma spp. is considered as a plant growth promoter and biocontrol fungal agents. They colonize on the surface of root in most of the agriculture crops. They secrete different secondary metabolites and enzymes which promote different physiological processes as well as protect plants from various environmental stresses. This is part of their vital functions. They are widely exploited as a biocontrol agent and plant growth promoter in agricultural fields. Colonization of Trichoderma with roots can enhance nutrient acquisition from surrounding soil to root and can substantially increase nitrogen use efficiency (NUE) in crops and linked with activation of plant signaling cascade. Among Trichoderma species, only some Trichoderma species were well characterized which help in the uptake of nitrogen-containing compound (especially nitrate form) and induced nitric oxide (NO) in plants. Both nitrate and NO are known as a signaling agent, involved in plant growth and development and disease resistance. Activation of these signaling molecules may crosstalk with other signaling molecule (Ca²⁺) and phytohormone (auxin, gibberellins, cytokinin and ethylene). This ability of Trichoderma is important to agriculture not only for increased plant growth but also to control plant diseases. Recently, Trichoderma strains have been shown to encompass the ability to regulate transcripts level of high-affinity nitrate transporters and probably it was positively regulated by NO. This review aims to focus the usage of Trichoderma strains on crops by their abilities to regulate transcript levels, probably through activation of plant N signaling transduction that improve plant health.

Comparative Proteomic Analysis Provides New Insights Into Low Nitrogen-Promoted Primary Root Growth in Hexaploid Wheat

Nitrogen deficient environments can promote wheat primary root growth (PRG) that allows for nitrogen uptake in deep soil. However, the mechanisms of low nitrogen-promoted root growth remain largely unknown. Here, an integrated comparative proteome study using iTRAQ analysis on the roots of two wheat varieties and their descendants with contrasting response to low nitrogen (LN) stress was performed under control (CK) and LN conditions. In total, 84 differentially abundant proteins (DAPs) specifically involved in the process of LN-promoted PRG were identified and 11 pathways were significantly enriched. The Glutathione metabolism, endocytosis, lipid metabolism, and phenylpropanoid biosynthesis pathways may play crucial roles in the regulation of LN-promoted PRG. We also identified 59 DAPs involved in the common response to LN stress in different genetic backgrounds. The common responsive DAPs to LN stress were mainly involved in nitrogen uptake, transportation and remobilization, and LN stress tolerance. Taken together, our results provide new insights into the metabolic and molecular changes taking place in contrasting varieties under LN conditions, which provide useful information for the genetic improvement of root traits and nitrogen use efficiency in wheat.

Ecological interactions shape the adaptive value of plant defence: Herbivore attack versus competition for light

Plants defend themselves against diverse communities of herbivorous insects. This requires an investment of limited resources, for which plants also compete with neighbours. The consequences of an investment in defence are determined by the metabolic costs of defence as well as indirect or ecological costs through interactions with other organisms. These ecological costs have a potentially strong impact on the evolution of defensive traits, but have proven to be difficult to quantify.We aimed to quantify the relative impact of the direct and indirect or ecological costs and benefits of an investment in plant defence in relation to herbivory and intergenotypic competition for light. Additionally, we evaluated how the benefits of plant defence balance its costs in the context of herbivory and intergenotypic competition.To this end, we utilised a functional-structural plant (FSP) model of Brassica nigra that simulates plant growth and development, morphogenesis, herbivory and plant defence. In the model, a simulated investment in defences affected plant growth by competing with other plant organs for resources and affected the level and distribution of herbivore damage.Our results show that the ecological costs of intergenotypic competition for light are highly detrimental to the fitness of defended plants, as it amplifies the size difference between defended and undefended plants. This leads to herbivore damage counteracting the effects of intergenotypic competition under the assumption that herbivore damage scales with plant size. Additionally, we show that plant defence relies on reducing herbivore damage rather than the dispersion of herbivore damage, which is only beneficial under high levels of herbivore damage.We conclude that the adaptive value of plant defence is highly dependent on ecological interactions and is predominantly determined by the outcome of competition for light. plain language summary is available for this article.

Know your enemy, embrace your friend: using omics to understand how plants respond differently to pathogenic and mutualistic microorganisms

Microorganisms, or 'microbes', have formed intimate associations with plants throughout the length of their evolutionary history. In extant plant systems microbes still remain an integral part of the ecological landscape, impacting plant health, productivity and long-term fitness. Therefore, to properly understand the genetic wiring of plants, we must first determine what perception systems plants have evolved to parse beneficial from commensal from pathogenic microbes. In this review, we consider some of the most recent advances in how plants respond at the molecular level to different microbial lifestyles. Further, we cover some of the means by which microbes are able to manipulate plant signaling pathways through altered destructiveness and nutrient sinks, as well as the use of effector proteins and micro-RNAs (miRNAs). We conclude by highlighting some of the major questions still to be answered in the field of plant-microbe research, and suggest some of the key areas that are in greatest need of further research investment. The results of these proposed studies will have impacts in a wide range of plant research disciplines and will, ultimately, translate into stronger agronomic crops and forestry stock, with immune perception and response systems bred to foster beneficial microbial symbioses while repudiating pathogenic symbioses.

Interactions between nitrate and ammonium in their uptake, allocation, assimilation, and signaling in plants

Nitrogen (N) availability is a major factor determining plant growth and productivity. Plants acquire inorganic N from the soil, mainly in the form of nitrate and ammonium. To date, researchers have focused on these N sources, and demonstrated that plants exhibit elaborate responses at both physiological and morphological levels. Mixtures of nitrate and ammonium are beneficial in terms of plant growth, as compared to nitrate or ammonium alone, and therefore synergistic responses to both N sources are predicted at different steps ranging from acquisition to assimilation. In this review, we summarize interactions between nitrate and ammonium with respect to uptake, allocation, assimilation, and signaling. Given that cultivated land often contains both nitrate and ammonium, a better understanding of the synergism between these N sources should help to identify targets with the potential to improve crop productivity.

Nitrate Transport, Sensing, and Responses in Plants

Nitrogen (N) is an essential macronutrient that affects plant growth and development. N is an important component of chlorophyll, amino acids, nucleic acids, and secondary metabolites. Nitrate is one of the most abundant N sources in the soil. Because nitrate and other N nutrients are often limiting, plants have developed sophisticated mechanisms to ensure adequate supply of nutrients in a variable environment. Nitrate is absorbed in the root and mobilized to other organs by nitrate transporters. Nitrate sensing activates signaling pathways that impinge upon molecular, metabolic, physiological, and developmental responses locally and at the whole plant level. With the advent of genomics technologies and genetic tools, important advances in our understanding of nitrate and other N nutrient responses have been achieved in the past decade. Furthermore, techniques that take advantage of natural polymorphisms present in divergent individuals from a single species have been essential in uncovering new components. However, there are still gaps in our understanding of how nitrate signaling affects biological processes in plants. Moreover, we still lack an integrated view of how all the regulatory factors identified interact or crosstalk to orchestrate the myriad N responses plants typically exhibit. In this review, we provide an updated overview of mechanisms by which nitrate is sensed and transported throughout the plant. We discuss signaling components and how nitrate sensing crosstalks with hormonal pathways for developmental responses locally and globally in the plant. Understanding how nitrate impacts on plant metabolism, physiology, and growth and development in plants is key to improving crops for sustainable agriculture.

Environmental Control of Root System Biology

The plant root system traverses one of the most complex environments on earth. Understanding how roots support plant life on land requires knowing how soil properties affect the availability of nutrients and water and how roots manipulate the soil environment to optimize acquisition of these resources. Imaging of roots in soil allows the integrated analysis and modeling of environmental interactions occurring at micro- to macroscales. Advances in phenotyping of root systems is driving innovation in cross-platform-compatible methods for data analysis. Root systems acclimate to the environment through architectural changes that act at the root-type level as well as through tissue-specific changes that affect the metabolic needs of the root and the efficiency of nutrient uptake. A molecular understanding of the signaling mechanisms that guide local and systemic signaling is providing insight into the regulatory logic of environmental responses and has identified points where crosstalk between pathways occurs.

Root-Root Interactions: Towards A Rhizosphere Framework

Plant scientists have made great progress in understanding molecular mechanisms controlling root responses to nutrients of arabidopsis (Arabidopsis thaliana) plants under controlled conditions. Simultaneously, ecologists and agronomists have demonstrated that root-root interactions involve more than competition for nutrients. Here, we highlight the importance of both root exudates and soil microbes for root-root interactions, ubiquitous in natural and agricultural ecosystems. We argue that it is time to bring together the recent insights from both scientific disciplines to fully understand root functioning in the real world.

The Scion/Rootstock Genotypes and Habitats Affect Arbuscular Mycorrhizal Fungal Community in Citrus

Citrus roots have rare root hairs and thus heavily depend on arbuscular mycorrhizal fungi (AMF) for mineral nutrient uptake. However, the AMF community structure of citrus is largely unknown. By using 454-pyrosequencing of 18S rRNA gene fragment, we investigated the genetic diversity of AMF colonizing citrus roots, and evaluated the impact of habitats and rootstock and scion genotypes on the AMF community structure. Over 7,40,000 effective sequences were obtained from 77 citrus root samples. These sequences were assigned to 75 AMF virtual taxa, of which 66 belong to Glomus, highlighting an absolute dominance of this AMF genus in symbiosis with citrus roots. The citrus AMF community structure is significantly affected by habitats and host genotypes. Interestingly, our data suggests that the genotype of the scion exerts a greater impact on the AMF community structure than that of the rootstock where the physical root-AMF association occurs. This study not only provides a comprehensive assessment for the community composition of the AMF in citrus roots under different conditions, but also sheds novel insights into how the AMF community might be indirectly influenced by the spatially separated yet metabolically connected partner—the scion—of the grafted citrus tree.

Complementarity in nutrient foraging strategies of absorptive fine roots and arbuscular mycorrhizal fungi across 14 coexisting subtropical tree species

In most cases, both roots and mycorrhizal fungi are needed for plant nutrient foraging. Frequently, the colonization of roots by arbuscular mycorrhizal (AM) fungi seems to be greater in species with thick and sparsely branched roots than in species with thin and densely branched roots. Yet, whether a complementarity exists between roots and mycorrhizal fungi across these two types of root system remains unclear. We measured traits related to nutrient foraging (root morphology, architecture and proliferation, AM colonization and extramatrical hyphal length) across 14 coexisting AM subtropical tree species following root pruning and nutrient addition treatments. After root pruning, species with thinner roots showed more root growth, but lower mycorrhizal colonization, than species with thicker roots. Under multi-nutrient (NPK) addition, root growth increased, but mycorrhizal colonization decreased significantly, whereas no significant changes were found under nitrogen or phosphate additions. Moreover, root length proliferation was mainly achieved by altering root architecture, but not root morphology. Thin-root species seem to forage nutrients mainly via roots, whereas thick-root species rely more on mycorrhizal fungi. In addition, the reliance on mycorrhizal fungi was reduced by nutrient additions across all species. These findings highlight complementary strategies for nutrient foraging across coexisting species with contrasting root traits.