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Abstract Desiccation tolerance (DT), the ability to survive near‐complete cellular dehydration, is widespread in diaspores but rare in the vegetative tissues of land plants. The patchy and punctuated phylogenetic distribution of vegetative desiccation tolerance (VDT) suggests that the trait is both ancient and recurrent, yet the evolutionary trajectories remain unresolved. Here, we synthesize evidence across land plants to propose a framework for the evolution of VDT in embryophytes. We build on the current understanding of VDT as an ancestral trait, present in the gametophyte of early land plants. The transition to sporophyte dominance and resulting homiohydry in vascular plants coincides with the widespread loss of VDT, likely driven by relaxed selection for VDT, coupled with new structural constraints and anatomical innovations that facilitated water acquisition, transport, and retention. The core molecular modules of DT were retained in the diaspores of most land plants, where they served as evolutionary refugia for the essential building blocks of the trait. Some species later reestablished VDT by co‐opting deeply conserved diaspore modules and evolving key anatomical innovations to support them. We argue that such reestablishments of VDT are dependent on both anatomical predispositions as well as exposure to key selective pressures and ecological filters. We conclude that VDT is not a simple presence–absence trait, but rather a modular system, subject to anatomical constraints and contingent on the ecological context. Ultimately, we suggest that VDT serves as an elegant example of how complex traits emerge, persist, and shift across time. 

Abstract Reforestation of degraded riparian areas provides climate mitigation benefits through increased carbon (C) storage. However, the magnitude of this potential natural climate solution (NCS) remains uncertain across ecoregions. Few studies have evaluated riparian planting C sequestration and storage, particularly in highly productive wet riparian ecosystems. In recent decades, riparian reforestation has accelerated in the Pacific Northwest (PNW) of the United States, primarily aiming to restore ecosystem functions and associated benefits. Using these plantings as a ‘natural experiment’, we assessed C storage in woody vegetation (trees and shrubs) and soils across a chronosequence of PNW riparian reforestation sites. Our study evaluated changes in C storage with planting age and identified key covariates affecting C storage in plants and soils and their relationship with planting age across a ∼430 km latitudinal gradient in western Oregon, USA. We found that woody and soil C stocks increase with planting age, averaging 24% and 1% per year, respectively. Increases in tree C were strongly driven by increasing planting age and tree stem density. Understory C was weakly related to stand characteristics and geomorphic properties, and strongly related to planting age. Soil C gains were positively driven by precipitation. We find that riparian reforestation can result in increased C storage, with woody vegetation comprising most of the increase. Our results highlight the importance of including both trees and shrubs in plantings to realize C accumulation gains in the earlier years. Because C accumulation is gradual, yet compounding (i.e. 10+ and 15+ years for total C stocks to increase by 1.95, and 19.2 Mg C ha⁻¹, respectively), riparian reforestation projects implemented today could take over a decade to deliver high NCS benefits, emphasizing the urgency to implement these projects to limit the worst of climate change impacts. 

Abstract Physiologically relevant drought stress is difficult to apply consistently, and the heterogeneity in experimental design, growth conditions, and sampling schemes makes it challenging to compare water deficit studies in plants. Here, we reanalyzed hundreds of drought gene expression experiments across diverse model and crop species and quantified the variability across studies. We found that drought studies are surprisingly incomparable, even when accounting for differences in genotype, environment, drought severity, and method of drying. Many studies, including most Arabidopsis (Arabidopsis thaliana) work, lack high-quality phenotypic and physiological datasets to accompany gene expression, making it challenging to assess the severity or consistency of water deficit stress events. To help address this, we developed supervised learning classifiers that can distinguish RNAseq samples that likely experienced drought stress. While not a substitute for direct measurements, these classifiers may aid in interpreting existing datasets and assessing drought severity in studies lacking physiological metadata. Together, our analyses highlight the importance of paired physiological data to quantify stress severity for reproducibility and future data analyses. 

Abstract In recent years, a deluge of big and diverse datasets from hundreds of plant species coupled with spectacular innovations in artificial intelligence (AI) and generative AI (GenAI), has altered the landscape of plant science. These developments are increasingly democratizing the field, reducing the entry barriers to complex data analysis and enabling a new wave of innovative research while introducing new challenges. Therefore, in this era, it is critical that we train the next generation of plant scientists to be AI-literate, i.e., not only proficient in using AI but also vigilant about its pitfalls and biases. In this Perspective, we call for six strategic shifts necessary for training the next generation of plant scientists. We argue that while maintaining a core focus on subject expertise, educators should simultaneously emphasize development of new AI-forward pedagogical and evaluation frameworks that reward interdisciplinary and critical thinking, human-driven knowledge synthesis, self-directed learning, and conceptual understanding of workflows. For effective critique and sound interpretations based on biological reality, plant scientists must be explicitly trained in recognizing biases underlying GenAI models. Finally, we highlight the structural barriers hindering the equitable and ethical use of GenAI, where awareness and resolution is critical for sustainable growth of the field. Through the above conceptual framework and numerous plant-science focused illustrative activities, examples, and resources meant for students and educators alike, this Perspective defines high-level emphasis areas for GenAI-enabled scientific training, aimed at creating a more effective, engaged, and adaptive community of plant scientists. 

Abstract The Virgo Filament Survey (VFS) is a comprehensive study of galaxies that reside in the extended filamentary structures surrounding the Virgo Cluster, out to 12 virial radii. The primary goal is to characterize all of the dominant baryonic components within galaxies and to understand whether and how they are affected by the filament environment. A key constituent of VFS is a narrowband Hαimaging survey of over 600 galaxies, VFS-Hα. The Hαimages reveal detailed, resolved maps of the ionized gas and massive star formation. This imaging is particularly powerful as a probe of environmentally induced quenching because different physical processes affect the spatial distribution of star formation in different ways. In this paper, we present the first results from the VFS-Hαfor the NGC 5364 group, a low-mass ( ${\log }_{10}(M_{\mathrm{dyn}}/M_{\odot })<13$ ) system located at the western edge of the Virgo III filament. We combine Hαimaging with resolved Hiobservations from MeerKAT for eight group members. These galaxies exhibit peculiar morphologies, including strong distortions in the stars and the gas, truncated Hiand Hαdisks, H itails, extraplanar Hαemission, and off-center Hαemission. These signatures are suggestive of environmental processing such as tidal interactions, ram pressure stripping, and starvation. We quantify the role of ram pressure stripping expected in this group, and find that it can explain the cases of Hitails and truncated Hαfor all but one of the disk-dominated galaxies. Our observations indicate that multiple physical mechanisms are disrupting the baryon cycle in these group galaxies. 

Abstract Desiccation tolerance evolved recurrently across diverse plant lineages to enable survival in water-limited conditions. Many resurrection plants are polyploid, and several groups have hypothesized that polyploidy contributed to the evolution of desiccation tolerance. However, due to the vast phylogenetic distance between resurrection plant lineages, the rarity of desiccation tolerance, and the prevalence of polyploidy in plants, this hypothesis has been difficult to test. Here, we surveyed natural variation in morphological, reproductive, and desiccation tolerance traits across several cytotypes of a single species to test for links between polyploidy and increased resilience. We sampled multiple natural populations of the resurrection grass Microchloa caffra across an environmental gradient ranging from mesic to xeric in South Africa. We describe two distinct ecotypes of M. caffra that occupy different extremes of the environmental gradient and exhibit consistent differences in ploidy, morphological, reproductive, and desiccation tolerance traits in both field and common growth conditions. Interestingly, plants with more polyploid genomes exhibited consistently higher recovery from desiccation, were less reproductive, and were larger than plants with smaller genomes and lower ploidy. These data indicate that selective pressures in increasingly xeric sites may play a role in maintaining and increasing desiccation tolerance and are mediated by changes in ploidy. 

Abstract Recent theoretical work and targeted observational studies suggest that filaments are sites of galaxy preprocessing. The aim of the WISESize project is to directly probe galaxies over the full range of environments to quantify and characterize extrinsic galaxy quenching in the local universe. In this paper, we useGALFITto measure the IR 12μm (R₁₂) and 3.4μm (R_3.4) effective radii of 603 late-type galaxies in and surrounding the Virgo cluster. We find that Virgo cluster galaxies show smaller star-forming disks relative to their field counterparts at the 2.5σlevel, while filament galaxies show smaller star-forming disks to almost 1.5σ. Our data, therefore, show that cluster galaxies experience significant effects on their star-forming disks prior to their final quenching period. There is also tentative support for the hypothesis that galaxies are preprocessed in filamentary regions surrounding clusters. On the other hand, galaxies belonging to rich groups and poor groups do not differ significantly from those in the field. We additionally find hints of a positive correlation between stellar mass and size ratio for both rich group and filament galaxies, though the uncertainties on these data are consistent with no correlation. We compare our size measurements with the predictions from two variants of a state-of-the-art semi-analytic model (SAM), one which includes starvation and the other incorporating both starvation and ram pressure stripping (RPS). Our data appear to disfavor the SAM, which includes RPS for the rich group, filament, and cluster samples, which contributes to improved constraints for general models of galaxy quenching.