Genome-wide polymorphism data are increasingly used in conservation biology, and new developments in theoretical population genomics generate refined statistical inference methods. Most theories and methods remain based on human life-history traits and genome characteristics, namely, that the ratio of the population rates of recombination over mutation is approximately one. However, most fungal, invertebrate or plant species exhibit violations of the classic population genetics models due to their peculiar life cycles, such as long-life span and generation overlap, dormancy, clonality, selfing and large variance in offspring production (sweepstakes reproduction). We first present applicable inference methods accounting for these life-history traits. Second, we highlight new inference methods to estimate the timing and magnitude of changes in these traits over evolutionary times. We suggest that methodological and theoretical novelties pave the way to dissect the causes and consequences of changes in ecological and evolutionary (life-history) traits in plant species and in multi-species assemblages (communities) in response to changing environments.

Floral traits determine the reproductive success and the fitness of a plant. We investigated the effect of ambient temperature on three floral and four fitness traits and their plasticities in 34 Arabidopsis thaliana accessions grown at 17 °C, 20 °C, 24 °C and 27 °C. Based on reaction norms of the mean trait values across temperatures, we found that these traits exhibited different degrees of temperature-mediated plasticity. Flower number, measured as number of siliques and number of seeds per silique, showed significant positive correlations with total seed number at each tested temperature, indicating that seed number in siliques is an indicator for reproductive output. The correlation of flower size with the latitudinal origin of the accessions indicates that in the north, larger flowers may confer an adaptive advantage. Altogether, this study provides information on the impact of increased temperature on fitness in selfing A. thaliana.

Pavement cells in the Arabidopsis thaliana epidermis span a wide range of sizes and ploidy levels, but rules that generate this heterogeneity across an organ remain unclear. Clark et al. identify a shared genetic pathway that promotes large, polyploid pavement cells in both sepals and leaves, then ask whether the familiar “scattered” distribution of giant cells is truly random. By combining whole-tissue imaging with two independent computational randomization approaches that regenerate tissues from segmented images while preserving cell size distributions and key boundary constraints, together with a stochastic cell-autonomous model, the authors show how an initially random pattern can later appear clustered relative to a changing random baseline as tissues grow and subdivide. The study provides a quantitative framework for testing spatial organization in cellular mosaics where point-based methods fail, and it shows how proliferation history can convert early stochastic fate decisions into a statistically non-random mature pattern.

Plant development relies not only on intracellular biochemical signals but also on physical information that is transmitted across cells and tissues. In growing plant organs, surface geometry and mechanics can act together to channel stress and strain signals beyond the single cell, effectively creating trans-cellular communication pathways that are robust, accurate and instantaneous. It follows that meristematic surfaces act as stress-mechanical waveguides to constrain and redirect internal stress fields. The orientation and patterning of these stress fields correlates with the placement of new cell walls during cell division, thereby linking surface geometry to tissue histogenesis. Here, I consider how meristem surfaces may contribute to developmental signaling via mechanical force transmission. I argue that surface curvature and tissue biomechanics can form a self-sustaining feedback loop: together, they shape force transmission trajectories, which in turn guide the fundamental decision-making processes that determine cell plate orientation during cytokinesis, thus altering organ shape.

Nitrogen (N) is a major plant nutrient, and its supply is very often limiting growth. The main forms of inorganic N in soil supplying plants are ammonium and nitrate ions. Although the soil availability of N can vary greatly, the cytoplasmic nutrient ion activities in a typical plant cell are maintained at set points that are independent of changes in supply. By contrast, the storage of N as protein and vacuolar nitrate depends on the external supply. Measurements of cellular homeostasis of ammonium and nitrate are limited by methodology. The upper limits for cytoplasmic set points are likely to depend on toxicity, and for ammonium this is well known but less clear for nitrate. An intracellular set point for N must be maintained by membrane transport systems and assimilation processes. Crop N use efficiency has uptake and assimilation components, and understanding homeostasis is fundamentally important for improving this important trait.

Advances in LED lighting technologies enable increasingly complex light regimes, providing greater insight into plants’ responses to dynamic light – such as seasonality and fluctuating conditions – rather than the traditional discrete (i.e., on/off) lighting. However, current methods of programming such regimes are time-consuming and/or limited to 1–2 wavebands. Robust methods are therefore needed to accurately programme multichannel/waveband LED lighting systems. We present a multistep, multidimensional algorithm to accurately programme multi-waveband LED lights. This algorithm accounts for non-linearity between intensity settings and measured light quantity output, as well as optical crosstalk between channels of different wavebands. It outperforms methods that treat waveband channels as independent variables, allowing users to more accurately programme multichannel light regimes. This will allow the community to probe plant responses to dynamically changing light spectra. We have made this algorithm available as an R package, LightFitR (installable from CRAN with ‘install.packages(“LightFitR”)’.

Wood density (WD) is a crucial anatomical trait influencing forest carbon storage. However, dynamic global vegetation models (DGVMs) typically assume a fixed species-level WD, neglecting environment-driven variability. In this proof-of-concept study, we explore the potential impact of dynamic WD on tree- and forest-level carbon storage by integrating a simple temperature-response function of WD into the DGVM LPJ-GUESS from Smith et al., 2014.

Simulations along a temperature gradient show that incorporating environmentally responsive WD can substantially alter simulated stand structure and carbon stocks. Overall, our model experiments illustrated that sites with higher WD had more, but smaller trees, which stored less carbon compared to the standard model. The strongest effects were predicted to appear before canopy closure, where per-tree carbon deviated by up to 32%. This exploratory study suggests the need to represent a mechanism for dynamic WD to better assess ecological feedbacks to forest carbon storage predictions, particularly in young and regenerating forests.

Understanding wood formation is critical for interpreting tree growth and carbon allocation under changing environmental conditions. While major progress has been made for gymnosperms, harmonized approaches for studying xylogenesis in angiosperms remain limited. Here, we present practical recommendations for observing and analysing xylogenesis in angiosperm trees, illustrated from examples from temperate and sub-Mediterranean forests. The perspective includes guidance on identifying xylem cell types in histological sections, defining developmental phenophases and establishing a workflow for data collection (and analysis). Annotated images are provided to support reproducibility and inter-observer consistency. We also discuss key challenges unique to angiosperms, including cell-type-specificities and wood type differences. Future research priorities include conserving histological images, extending xylogenesis to branches and coarse roots, enabling cross-biome comparisons and advancing kinetic analysis. This framework supports the coordinated expansion of angiosperm xylogenesis studies, enabling deeper insights into tree functioning in a changing world.

Disentangling how forests respond to aridification in terms of carbon storage and use, including bimodal growth, is critical to forecast their mitigation potential. Bimodality, characteristic of Mediterranean trees, refers to the potential to produce a second growth peak after the dry summer, often accompanied by intra-annual wood density fluctuations (IADF). To induce IADF formation, we performed a girdling experiment on Spanish juniper (Juniperus thurifera) branches in a semi-arid site, and monitored changes in branch diameter, and measured non-structural carbohydrate (NSC) concentrations in sapwood and leaves. IADFs were formed in response to wet conditions in late summer in girdled and non-girdled branches. After girdling, the extraordinarily dry 2022 growing season hampered branch radial increment and IADF production. Girdled branches swelled more than control branches after rain pulses. This suggests girdled branches were osmotically more active. Girdled branches presented higher starch leaf concentrations, suggesting that osmolytes could proceed from starch hydrolysis upstream. Girdling did neither trigger bimodal growth nor IADF formation during a very dry year.

Magnesium (Mg2+) is essential for plant growth and metabolism, acting as a cofactor in numerous enzymatic and structural processes. This review outlines the main physiological and biochemical functions of Mg2+ and summarizes current knowledge on its transport and homeostatic regulation. We examine how Mg2+ homeostasis intersects with broader signalling networks and metabolic pathways, including its crosstalk with other mineral nutrients, where antagonistic and synergistic interactions influence nutrient acquisition, allocation and stress responses. Emerging evidence further suggests that, beyond its classical roles, Mg2+ may function as a regulatory ion with signalling properties reminiscent of secondary messengers in animal systems. Finally, we highlight recent findings linking Mg2+ dynamics to circadian regulation, suggesting reciprocal interactions between temporal control mechanisms and nutrient fluxes. These insights underscore the central importance of Mg2+ in plant biology and identify key gaps in understanding its regulatory and integrative roles.

Agronomic research has long prioritized efficiency – optimizing resource use to maximize yield under stable conditions. However, as climate variability intensifies, efficiency alone might be insufficient to sustain agricultural production in the future. Instead, robustness – the ability to maintain function across diverse and unpredictable environments – emerges as a critical trait. Robustness is not a simple metric but an emergent property, arising from the interplay of redundancy, heterogeneity and plasticity across biological scales. We examine how the components of robustness (redundance, heterogeneity and plasticity) express themselves at the anatomical, architectural and genomic scale. A major challenge is the lack of a unified framework to measure robustness. We propose integrating empirical metrics – such as vessel grouping indices, root trait heterogeneity and gene expression plasticity – with computational models to quantify redundancy, heterogeneity and plasticity. By synthesizing insights from physiology, genomics and modelling, we outline a path towards designing crops that thrive in ideal settings and under environmental uncertainty.

Copper is an essential micronutrient that plays critical roles in plant metabolism, development and stress responses through its unique redox properties. While tightly regulated to prevent toxicity, labile copper also functions as a dynamic signalling molecule mediating developmental and environmental cues. Copper bioavailability in soils is influenced by complex physicochemical factors, posing challenges for plant acquisition and homeostasis. Plants have evolved sophisticated mechanisms to regulate copper uptake, long-distance transport, intracellular trafficking and storage, balancing its essentiality with potential toxicity. This review summarizes current knowledge on copper homeostasis in plants, discusses uptake strategies in dicots and non-grass monocots, the coordination of internal copper transport and tissue distribution, and the emerging evidence for systemic copper signalling. Understanding these processes is important for improving crop nutrient use efficiency and resilience in mineral-deficient soils.

The impact factor has become a defining feature of scientific journals. However, such reductionism can be toxic to science. As Cambridge University Press Quantitative Plant Biology celebrates its 5-year anniversary, and its first impact factor, this is an opportunity to set things straight. A call to value what a scientific journal is about: a community of scientists, a guarantee of rigour and quality, an invitation to explore the complexity of our world, a fair and ethical environment and an engaging, diverse and creative arena.

Numerous studies have investigated the impact of climate change on tree growth and carbon sequestration, exploring the effect of climatic factors on the onset and cessation of wood formation. Some studies used microcores for histological observations of xylem, while many others used dendrometer recordings to infer stem growth. However, the reliability of dendrometers in providing accurate estimates of growth phenology has yet to be fully assessed. We compared the phenology estimated using dendrometer- and microcore-based approaches for six tree species growing in contrasted site conditions and exhibiting contrasted tree-ring structures (non-porous, diffuse-porous and ring-porous) and bark types (smooth, scaled, fissured). Our results show that dendrometer estimate accuracy is poor and varied according to several factors, including species life traits, climate and site conditions. These results highlight the limitations of dendrometers in evaluating wood phenology in trees, and advocate for the concurrent monitoring of xylogenesis.

Water deficit at the plant cell level can be assimilated to a reduction in turgor pressure and an increase in osmotic pressure. In a previous work, we showed that the mRNA abundance of some genes displays a quantitative relationship to these physicochemical parameters. Biomolecular condensates have been shown to depend on the physicochemical environment and are known to regulate mRNA fate. In this review, we present recent work about the implication of biomolecular condensates in mRNA regulation of plants under water deficit and question the biophysical origin of their dynamics. Data in the literature suggest that while the perception of mild water deficit may have been overlooked, biomolecular condensates are clear candidates to sense and transduce severe water deficit in plant cells.

The shape of plants can be sensitive to dehydration. Here, we focus on herbaceous plants whose petiole cross-section is U-shaped and contains a lot of water. Among a large range of plants showing the same behaviour, we examine Spathiphyllum that exhibits a pronounced, sudden but reversible drooping under dehydration. We show that it is the consequence of a high-amplitude hinge mechanism located at the base of its long petioles, similar to a carpenter’s tape folding under sufficient load. Mechanical testing demonstrated that small-amplitude bending rigidity decreases by only a factor of three during dehydration, due to tissue shrinkage rather than material softening. The petiole is composed of water-rich parenchyma tissue: drooping occurs abruptly at 35%–40% of mass loss, remaining reversible unless dehydration is prolonged. Inspired by these observations, we introduce a biomimetic hinge which offers a programmable bending stiffness and nonlinear behaviour under load, with applications in computing mechanical metamaterials.

Linker histone H1 is crucial for chromatin organization and gene expression in Arabidopsis thaliana, influencing development and stress responses. To explore its role in diurnal gene regulation, we examined H1-deficient plants and found that H1 is essential for maintaining rhythmic gene expression. Genes losing synchronization often contained NAC transcription factor binding sites, indicating H1 may affect their accessibility. Nuclear imaging revealed that H1 subtly modulates nuclear size and chromatin distribution across the photoperiod. Epigenetic analysis showed typical diurnal changes – declines in H3K4me3 and active RNA Pol II in the evening and increases in H3K27me3. In H1 mutants, these patterns persisted but with elevated H3K4me3 and RNA Pol II (Ser2P) levels at night and in the morning. These results suggest that H1 fine-tunes chromatin and transcriptional rhythms, contributing to the temporal coordination of gene activity in response to environmental and developmental signals.