A central goal of evolutionary biology is to understand the mechanisms conferring adaptation. Gene expression is sensitive to environmental variability; thus, investigating gene expression differentiation among populations may reveal signatures of selection from predictable environmental conditions. Environmental pressures which covary with elevation gain (e.g. temperature) result in stark environmental differences along short distances. The phenological and life history traits of plants inhabiting elevational gradients might track these variables, providing an opportunity for testing hypotheses. Boechera stricta occupies a steep elevation gradient in the Rocky Mountains. Here, we grew F3 seeds from at least two genotypes each from five populations of B. stricta in a greenhouse. Analysis of leaf RNAseq data permitted tests of these hypotheses: 1) populations exhibit significant among population genetic variation in gene expression; 2) differentiation in gene expression (QST) exceeds neutral expectations (FST); and 3) the putative functions of differentially expressed genes are predictable based on a priori knowledge of environmental pressures which vary with elevation. Differentiation in gene expression (average QST = 0.53) significantly exceeded neutral differentiation (average FST = 0.17), implicating selection as a potential cause of genetically divergent patterns of gene expression. The putative functions of differentially expressed genes covarying with elevation were enriched for biological processes related to conditions which vary with elevation (circadian rhythm, response to light, chloroplast organization, and vegetative to reproductive meristem transitions). This study reveals considerable differentiation in gene expression, which may provide a mechanism for rapid adaptation to local environmental conditions in this and other species.

Abstract In sandy desert environments, plants experience substantial variation in growing conditions throughout the dune fixation process. Despite its ecological importance, the link between xerophytic plant trait adaptation and dune stabilization remains poorly understood. To address this gap, we evaluated 13 leaf functional traits related to physiological, structural, and biochemical properties in selected xerophytic species across four dune stabilization stages in northwest China, namely semi-fixed dunes (D1; vegetation cover, 23%), fixed dunes (D2; 32%), biocrusted-fixed dunes (D3; 46%), and herbaceous-plant-fixed dunes (D4; 60%). We applied leaf trait network (LTN) analysis to explore complex trait interrelationships and assess changes in network parameters during stabilization. Results revealed that both leaf traits and LTNs varied with stabilization stage. At the fixed dune stage (D2), xerophytes shifted from a resource-acquisitive strategy emphasizing rapid carbon and nutrient uptake to a more conservative strategy characterized by slower returns on investment. Leaf trait network connectivity increased with stabilization, as indicated by decreasing average path length and increasing edge density. Connectivity was positively correlated with soil bulk density (BD) and negatively correlated with soil volumetric water content, suggesting that increasing BD and water stress drove plants to adopt broader trait combinations, enhancing stress tolerance and physiological plasticity during dune stabilization.

Effects of solar panels and management on soil mesofauna, respiration and plant traits in solar parks of two southern French regions.

Rational fertilization is a key measure for improving grassland productivity; however, the optimal effects of nitrogen (N), phosphorus (P) and potassium (K) rationing vary across grasslands with different salinity–alkalinity conditions. To determine the optimum fertilization ratio for typical saline–alkaline degraded grasslands in the agro-pastoral transition zone of northern China, we carried out an experiment with different ratios of N, P and K to investigate the effects of fertilization on biomass, plant diversity, plant nutrient uptake and soil nutrient contents. The results showed that fertilization increased biomass, plant diversity, nutrient uptake and soil nutrient contents in all levels of saline–alkaline grasslands. Compared with the control, N2P2K2 treatment resulted in the significantly highest biomass, with an increase of 4.52 and 2.39 t ha−1 in slightly and moderately saline–alkaline grasslands; N2P2K1 resulted in the significantly highest biomass, with an increase of 1.14 t ha−1 in severely saline–alkaline grasslands. We integrated plant and soil properties to construct a second-order response surface model (RSM), and our recommended optimum N–P–K fertilization ratios for slightly, moderately and severely saline–alkali grasslands are 103.7–88.1–78.0, 125.5–91.5–74.1 and 85.2–68.1–58.2 kg ha−1, respectively. Reasonable fertilization can improve soil fertility, biomass yield and plant diversity, while excessive fertilization has negative effects on soil and plant traits. Our results provide theoretical support and practical guidance for the scientific fertilization of grasslands with varying salinity and alkalinity.

The causal role of pollinators in driving the divergence of plant traits is a fundamental tenet of angiosperm evolution, providing hallmark examples of natural selection. However, it remains unclear how geographic variation in pollinator assemblages relates to the divergence of pollination traits in pollination-generalized plants. We characterized pollinator assemblages that interacted with Viscaria vulgaris in southern Sweden, and evaluated, through statistical dimension reduction, whether pollination traits were associated with an inferred main axis of geographic variation in pollinator assemblages. We documented a functionally broad range of pollinators that visited V. vulgaris. Although the most frequent pollinator functional groups were present in most populations, their relative contribution to flower visitation varied across the study area, establishing a geographic mosaic of local pollinator assemblages. We demonstrate that the geographic variation of local pollinator assemblages can predict the divergence of pollination traits in V. vulgaris. The findings of this geographic comparative study are consistent with the hypothesis that geographic variation in pollinator assemblages drives the divergence of pollination traits in pollination-generalized plants. Thus, generalized plant-pollinator interactions do not preclude the divergence of pollination traits, which may maximize the collective contribution of local pollinator assemblages rather than that of a principal pollinator.

Soil salinization is a global ecological issue that severely constrains forest tree growth and ecological restoration. The salt-alkali stress response mechanisms of Quercus mongolica, a key temperate forest species in China, remain unclear. A two-factor pot experiment was conducted using NaCl (0, 50, 100, 200 mmol·L−1) and NaHCO3:Na2CO3 (1:1; 0, 50, 100, 150 mmol·L−1). Plant traits, soil properties, and enzyme activities were measured. Furthermore, high-throughput sequencing revealed that microbial responses enhanced network cooperation under 100 mmol·L−1 salt stress and improved network stability under 50 mmol·L−1 alkali stress. These responses also upregulated resistance genes and increased soil enzyme activities. This activation of seedling antioxidant and osmotic adjustment systems was directly associated with an increase in growth parameters. Under combined stress, however, soil environment deterioration and microbial network disruption, along with reduced key soil enzyme activities, resulted in an insufficient defense system to counteract reactive oxygen species (ROS) accumulation, thereby reducing growth parameters. The study found that low-concentration individual salt or alkali stress promoted Quercus mongolica seedling growth, while combined stress was associated with significant inhibition. This study refines the theoretical framework for non-salt-tolerant trees and establishes a basis for determining their survival thresholds in saline-alkali soils.

The island rule predicts gigantism or dwarfism in body size of island species relative to their mainland counterparts. However, whether other functional traits shift and whether trait-trait associations on islands differ between species and community levels remains unclear. We measured 13 carbon- and water-related functional traits in 37 shared tree species across 35 eastern Chinese islands and 66 nearby mainland plots. We examined species-level trait value shifts and associations under the island rule and compared trait associations between species and communities. Most size-related, wood-anatomical, and hydraulic traits shifted on islands, with large values decreasing and small values increasing; yet, their associations remained stable, aligning with the global trait spectrum and trait-trait coevolution. This stability, despite trait valueshifts, suggests evolutionary integration of functional strategies. By contrast, island community-scale trait associations diverged from shared species-level patterns and sometimes reversed, such as positive relationships between wood density and resource-acquisitive traits. Community-level trait associations were stronger on islands, likely reflecting constrained environmental filtering and migration limitation. These contrasting patterns suggest that dominant species can restructure trait associations at the community level, with implications for ecosystem functioning and carbon storage, thereby advancing understanding of plant trait strategies in island systems.

Anthropogenic nitrogen enrichment is widely expected to suppress symbiotic nitrogen fixation in terrestrial ecosystems. Nevertheless, observed symbiotic nitrogen fixation responses remain incompletely explained by exogenous nitrogen inputs, climate, and edaphic factors. In this meta-analysis, we integrate 908 globally distributed field measurements to identify the key predictors that improve simulation of symbiotic nitrogen fixation responses to nitrogen enrichment. On average, symbiotic nitrogen fixation declines by 33.0% upon nitrogen enrichment, with the reduction being more pronounced in non-croplands than croplands. Models considering only environmental factors overestimate symbiotic nitrogen fixation decline relative to observations. The better performance of plant traits like plant growth and biomass allocation (shoot:root ratio) partially buffer symbiotic nitrogen fixation suppression under nitrogen enrichment. Integrating both environmental factors and plant performance traits improves predictive accuracy of symbiotic nitrogen fixation responses by 42.7% and brings the simulated symbiotic nitrogen fixation reductions into close agreement with observations. The alterations in plant performance traits are thus critical for explaining variability in terrestrial symbiotic nitrogen fixation responses, and incorporating plant trait dynamics in Earth System Models can quantitatively partition the compensatory symbiotic nitrogen fixation supported by nitrogen-fixing plant growth from the direct negative impact of nitrogen inputs.

Flower color, as an important trait of ornamental plants, has been a research hotspot in recent years. In this study, we selected Prunus campanulata (Maxim.) (ZH, red), P. dielsiana (Schneid.) (WH, white), and two cherry blossom varieties 'Yanzhi Fei' (FH, deep pink) and 'Yanzhi Xue' (XH, pinkish white) obtained by open-pollination hybridization as material. By means of bioinformatics methods such as metabolomics and transcriptomics, it is expected to deeply study the molecular mechanism of the gradient changes in flower color between the parents and offspring of cherry blossoms. Metabolomics analysis indicated that a total of 84 flavonoid related metabolites were identified, among which 31 were associated with the anthocyanin metabolic pathway, including three major types of anthocyanin substances: cyanidin, delphinidin, and malvidin. Transcriptome analysis showed that a total of 7712 differential genes were detected between P. campanulata and P. dielsiana; there were 3948 differential genes between P. campanulata and 'Yanzhi Xue', 2802 between P. campanulata and 'Yanzhi Fei', and 2511 between 'Yanzhi Xue' and 'Yanzhi Fei'. After screening based on anthocyanin accumulation, nine key enzyme genes were obtained. Joint analysis showed that the relative expression trends of structural genes such as PAL, 4CL, CHI, DFR, and CYP75B in the samples were consistent with those of anthocyanins, and they had a high correlation with downstream metabolites. The results of this study lay a certain scientific foundation for the future directional improvement and breeding of cherry blossom colors.

Abstract Background and aims Drylands face increasing microplastic pollution. We tested how plastic particulates and leachable chemicals affect key dryland plants (grasses and forbs). Methods We performed two controlled experiments using dryland grasses and forbs, and evaluated the effect of plastic particulates and leachables on germination, plant morphological and physiological traits. Results Plastic particulates reduced grasses germination velocity by ~ 17% compared to soils without particulates, likely by trapping seeds and impairing water uptake. Most forbs were marginally affected, although germination was inhibited in mucilage-producing species. Notably, leachates stimulated forbs germination through hormesis, contrasting with particulates physical inhibition. For instance, E. vulgare velocity increased by ~ 20% with leachates than without them. However, this stimulation was transient and faded in later development. Grasses shoot mass decreased by ~ 21% with particulates, likely from soil water loss via plastic-induced cracks, an effect exacerbated by their shallow root systems. Forbs avoided this stress through deeper rooting and benefited from improved soil aeration, which enhanced shoot growth by ~ 61% compared to control. Grasses allocated carbon to stress tolerance, increasing photosynthetic rates (+ 15%) and water-use efficiency (+ 7.2%). Forbs favored shoot growth despite lower photosynthetis (-8.1%) and water-use efficiency (-25%), using thinner leaves and higher transpiration rates. Root morphology also critically influence tolerance to microplastics. The divergent particulate effects on grasses and forbs, reveal a mechanistic trade-off between stress tolerance and growth investment. Conclusion Microplastic particulates, more than leachates, drive plant responses, suggesting that plastic pollution may act as environmental filter by favoring stress-adapted forbs over grasses.

ABSTRACT Seed dispersal services are key to maintaining healthy forest ecosystems, yet our understanding of the factors that influence visitation and frugivory between conspecific plants remains incomplete. Although fruiting neighborhood, plant traits, and fruit traits have been shown to individually influence frugivory, few studies have concurrently evaluated the relative importance of these factors. We address this knowledge gap by simultaneously assessing multiple factors thought to influence frugivory. Specifically, we evaluated how the fruiting neighborhood, defined as the number of fruiting palms in a 35 m radius, and relevant traits at the level of individual plants (e.g., height, crop size) and fruits (e.g., fruit and seed size, water and sucrose content) influenced frugivore visitation and the number of fruits removed per visit in a common understory palm in Northwestern Ecuador, Synechanthus warscewiczianus . A higher number of conspecific fruiting neighbors exhibited a decrease in visitation, suggesting competition among palms that share frugivore mutualists for dispersal services. However, the number of fruits removed per frugivore visit appeared to be affected by crop size and fruit traits of individual palms. Larger crop and fruit sizes were positively associated with the number of fruits removed per visit and indicates frugivore satiation is not a main determinant of fruit consumption during visits. Taken together, our results suggest larger‐scale factors like fruiting neighborhood may affect a frugivore's decision to visit a palm, yet finer‐scale fruit traits may drive fruit removal once a palm is selected, thereby influencing variation in seed dispersal services at the individual plant level.

Abstract By dispersing seeds, animals provide ecological functions critical for the ecology, evolution, and conservation of plants. We review quantitative and empirical approaches and emerging technologies to quantify processes and patterns of animal‐mediated seed dispersal (zoochory) across its phases: from predispersal to postdispersal. In addition, we consider approaches to studying seed disperser behaviors and plant traits, both of which influence all dispersal phases of animal‐mediated dispersal. Finally, we discuss how we can use quantitative and empirical approaches to integrate across seed dispersal phases and address data gaps to improve our mechanistic understanding of zoochory and its consequences for ecology and conservation. To move towards generalization and predictability in seed dispersal ecology, we recommend the development of standardized protocols that can be widely implemented across systems with simultaneous and iterative development of theory and quantitative models. As approaches in studying animal‐mediated seed dispersal continue to advance, exciting opportunities present themselves to increase our understanding of seed dispersal ecology.

ABSTRACT The present study aims to analyze the relationship between aboveground biomass (AGB) and soil organic carbon (SOC) with plant traits and tree diversity of the 17 forest types of the temperate Himalayas. Leaf and stem traits, along with carbon, were measured across all the forests using 10 random 0.01 ha plots in each forest. The structural equation models for community weighted mean (CWM) and functional divergence (FDvar) were developed separately and jointly for AGB and SOC, each. All three models (CWM, FDvar, and jointly) for both AGB and SOC were significantly impacted by functional diversity metrics of traits and tree diversity, that is, Simpson index. The joint model for biomass had a significant relationship with CWM of diameter at breast height (DBH), tree height, leaf dry matter content, specific leaf area, photosynthetic rate, functional diversity of leaf nitrogen content (LNC), and Simpson index. However, SOC was positively impacted by the CWM of DBH and leaf phosphorus and FDvar of leaf carbon, and negatively by the CWM of LNC. The joint model indicated that dominant trait effects (mass‐ratio) primarily regulate SOC through stem and leaf trait means, whereas specific aspects of functional divergence contributed additional, weaker complementary effects. These patterns suggest that sustaining Himalayan temperate forests under changing environmental conditions requires conserving key species for maintaining functional trait diversity. The model results further imply that enhancing carbon storage can be achieved by promoting functional diversity, managing tree density and spatial structure, and aligning species selection with local environmental conditions.

Increased climate variability is expected to intensify short-term drought events. Plants have evolved stress tolerance strategies involving trade-offs in resource conservation, mycorrhizal collaboration and plant size, yet how these strategies promote drought resistance across different herbaceous plant groups remains unknown. Leveraging 63 globally distributed grassland and shrubland sites from the International Drought Experiment, we identified plant traits linked to drought resistance in 661 populations of 421 species after 1 year of extreme drought. We assessed how traits, site precipitation and drought severity affected cover change across growth forms and lifespans, and how trait-environment interactions influenced drought resistance. Across all species, leaf N (an acquisitive trait) was associated with drought resistance, whereas in forbs, drought resistance was also associated with a conservative root trait and plant size. In addition, interactions among traits mediated drought resistance; root traits predicted performance only in concert with other traits. Environmental variables influenced trait effects on drought resistance, notably for annuals in wetter sites, suggesting that drought-escape strategies in annuals may be advantageous only under mild stress. Our study highlights variability in traits that predict drought resistance across herbaceous plant groups, emphasizing the importance of species context, environmental stress and the selection of traits in research and management.

Polyploidization is a major macromutation, bearing notable genomic and ecological consequences. While the impact of polyploidy on plant abiotic niches is well studied, our understanding of its consequences on biotic interactions, and particularly pollination, is lacking and hardly includes its role in shaping plant-pollinator community structure. Here, we integrate hundreds of plant-pollinator networks, ploidy inferences, reproductive traits, and climatic attributes to ascertain whether a general pattern characterizes the link between polyploid frequency and network structure. We further examine whether environmental factors and plant traits known to be associated with polyploidy mediate this relationship. Our analysis reveals that an increased frequency of polyploid species within networks is positively associated with network nestedness while being negatively associated with modularity. Path analysis reveals that these associations are partially mediated via the frequency of self-compatible plants and by differences in flower shape. Despite these alterations in community structure, the heightened abundance of polyploids appears to have minimal impact on network connectance and resilience to extinction. Our findings indicate that unlike abiotic interactions, the relationships between polyploidy and biotic interactions are less predictable and reflect the combined contributions of phenotypic and environmental factors. However, we acknowledge that incomplete data sets limit a clear understanding of the causal relationship that may exist.

Root-knot nematodes (RKNs), Meloidogyne spp., exhibit a broad host range, threatening more than 3000 species of plants, including agriculturally important crops such as cotton (Gossypium hirsutum), tomato (Lycopersicon esculentum) and rice (Oryza sativa). Among the over 90 RKN species, the four most prevalent are M. incognita, M. arenaria, M. javanica, and M. hapla, with M. incognita being the most damaging. This paper reviewed the current RKN management strategies, including chemical nematicides, biological control, crop rotation, and resistant varieties, with a focus on the application of the revolutionary CRISPR/Cas genome editing tool in developing RKN resistance in plants. CRISPR/Cas has been widely utilized for improving crop traits due to its specificity, streamline, and inheritability. Recent progress has demonstrated the simplicity and robustness of CRISPR/Cas technology in improving plant traits. Among these, the development of nematode resistance by CRISPR/Cas knocking out of plant compatibility factors in model and commercial plants, has achieved significant progress. This review summarizes the RKN parasitism mechanisms and plant compatibility factors that would be promising CRISPR/Cas targets. The fundamentals and key aspects of CRISPR/Cas genome editing technology are addressed and discussed, and an example experimental pipeline for developing nematode resistance in cotton is described.

Understanding the role of site climate in driving geographic trait variation and revealing the relative contributions of adaptation and plasticity are key goals in plant sciences. We tested mechanistic hypotheses for trait-climate relationships for mature eucalypt trees grown in common garden and in situ field conditions, quantifying joint and individual effects of mean annual precipitation (MAP) and temperature (MAT) on eight functionally important traits. Trait-MAP relationships were particularly strong, with all but one trait consistently related to precipitation in both growth conditions. Trait-MAT relationships were notably weaker, but where relationships existed, most traits responded to low temperature in the same direction as to low rainfall, as predicted. Comparing cross-species trait-climate relationships in situ with trait-climate-of-origin relationships in the common garden indicated substantial contributions from both adaptation and plasticity, with plasticity contributing more to variation in photosynthetic traits than in leaf structural or wood traits. Two key advances were: teasing apart the roles of site temperature and rainfall on trait variation, which are often confounded; and inferring the contributions of adaptation and plasticity to observed trait patterns. The relative importance of these processes may determine the timescales over which plant traits shift with climate change.

Accurately representing African ecosystems in land surface models (LSMs) remains challenging due to the limited availability and accessibility of ecological data like plant traits. We systematically classified African plant species represented in the TRY plant trait database into Plant Functional Types (PFTs) consistent with those in the JULES LSM, to enable improvements of PFT parameterization in these models. From the TRY database plant trait observations were obtained representing 2,082 plant species. We assigned classification parameters including growth form, leaf type, leaf phenology, photosynthetic pathway and climate zone using multiple sources. This delivered a sixfold increase in number of plant species that could be mapped to PFT classes from 265 to 1603 representing 137 families. It delivered a fivefold increase in the number of useable observations among the 27 traits evaluated. Our lookup table can be used to integrate existing plant trait data into PFT parameterisations in land surface models and similar large scale modelling exercises, to enhance the representation of African ecosystems and improve their capacity to simulate African ecosystems.

Abstract Biochar is suggested to enhance the phytoremediation of cadmium (Cd) via regulating the rhizosphere environment and plant traits in contaminated soil. However, the effect of phosphorus (P)-modified biochar, the rhizosphere effect, and their interaction in improving phytoremediation efficiency of Salix for Cd remains unclear. Here, the effects of bamboo biochar, phytic acid-modified biochar, and sodium phytate-modified biochar on soil properties, the microbial community, plant traits, and Cd accumulation of Salix J1010 in Cd contaminated soil were comparatively and systematically studied. P-modified biochar significantly increased plant growth, Cd accumulation, and its translocation from roots to the aboveground parts of Salix . Cd concentration, root biomass, net photosynthetic rate, and rhizosphere microbial community variations were identified as critical predictors for phytoremediation efficiency using random forest models. Rhizosphere bacteria were more influenced by biochar amendment, while the fungi were more influenced by the rhizosphere effects. A key bacterial cluster, with a preference for high soil carbon and P, was further found to stimulate root growth and improve the bioavailability of soil Cd. Collectively, the study revealed differentiated responses of bacteria and fungi to biochar and rhizosphere effects of Salix , highlighting the importance of biochar modifications to optimize microbial interactions and enhance the phytoremediation efficiency of Salix in Cd-contaminated soils. Graphical Abstract

The first summer after fire poses a high risk of drought mortality for species that rely on postfire recruitment for their persistence in fire-prone ecosystems (postfire seeders). However, little is known about how future conditions of elevated atmospheric CO2 (eCO2) and its interaction with severe drought will affect this key life history strategy in Mediterranean shrublands. We investigated the extent that eCO2 modifies plant traits and resource allocation, as well as how eCO2 and drought intensity interact to modify plant water status, water fluxes, and hydraulic behavior in eight-month-old seedlings of five seeder shrub species. Among the studied species, three regenerate postfire exclusively by seed (non-resprouting seeders), while two can also resprout after fire (resprouting seeders). We found that eCO₂ significantly reduced specific leaf area for all species and increased above- and belowground biomass for three species but had no species-specific effects on stomatal density or root-to-shoot ratios. When species were grouped by resprouting ability, eCO2 reduced root-to-shoot ratios in resprouting species but not in non-resprouting species. Importantly, eCO2 did not affect plant water relations under drought either at the species level or when grouped by resprouting ability. However, resprouting and non-resprouting seeders exhibited distinct water-use strategies under drought, independent of CO₂ treatment. Overall, eCO₂ is unlikely to mitigate drought stress for postfire seeders in future climates. Considering functional differences across life history strategies, as well as the variability of traits within them, is key to predicting future patterns of biodiversity in a drier and more fire-prone world.