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This document is a corrigendum to an article published in the New Phytologist journal. The authors of the original article have identified errors in their work. Specifically, the equation used for carotenoid quantification in the Materials and Methods section was incorrect, resulting in incorrect graphs. The corrected equation and graphs are provided in the corrigendum. The errors do not change the conclusions of the paper. The authors apologize for the mistakes. [Extracted from the article]

Summary: Greenbeards are selfish genetic elements that make their bearers behave either altruistically towards individuals bearing similar greenbeard copies or harmfully towards individuals bearing different copies. They were first proposed by W. D. Hamilton over 50 yr ago, to illustrate that kin selection may operate at the level of single genes. Examples of greenbeards have now been reported in a wide range of taxa, but they remain undocumented in plants. In this paper, we discuss the theoretical likelihood of greenbeard existence in plants. We then question why the greenbeard concept has never been applied to plants and speculate on how hypothetical greenbeards could affect plant–plant interactions. Finally, we point to different research directions to improve our knowledge of greenbeards in plants. [ABSTRACT FROM AUTHOR]

Gary Loake, a professor of plant molecular sciences at the University of Edinburgh, shares his journey and passion for plant science. Growing up in a rural area, Loake developed a love for nature and biology, which led him to pursue a career in research. He transitioned from studying microbes to plants and has since focused on understanding and enhancing plant immunity. Loake is motivated by making new discoveries, solving problems, and mentoring students. He has also been involved in industry collaborations and founded a plant biotechnology company. Loake highlights the importance of role models in his career and mentions his favorite papers from the New Phytologist journal. He also shares his favorite plant, the horse chestnut tree, and discusses his work with the model plant Marchantia polymorpha. Unfortunately, the article notes that Loake passed away in March 2024. [Extracted from the article]

Summary: Drought is intensifying globally with climate change, creating an urgency to understand ecosystem response to drought both during and after these events end to limit loss of ecosystem functioning. The literature is replete with studies of how ecosystems respond during drought, yet there are far fewer studies focused on ecosystem dynamics after drought ends. Furthermore, while the terms used to describe drought can be variable and inconsistent, so can those that describe ecosystem responses following drought. With this review, we sought to evaluate and create clear definitions of the terms that ecologists use to describe post‐drought responses. We found that legacy effects, resilience and recovery were used most commonly with respect to post‐drought ecosystem responses, but the definitions used to describe these terms were variable. Based on our review of the literature, we propose a framework for generalizing ecosystem responses after drought ends, which we refer to as 'the post‐drought period'. We suggest that future papers need to clearly describe characteristics of the imposed drought, and we encourage authors to use the term post‐drought period as a general term that encompasses responses after drought ends and use other terms as more specific descriptors of responses during the post‐drought period. [ABSTRACT FROM AUTHOR]

This article is a Commentary on the Virtual Issue 'Methane emissions from tree stems – current knowledge and challenges' that includes the following papers: Barba et al. (2019), Bréchet et al. (2021), Covey & Megonigal (2019), Feng et al. (2022), Flanagan et al. (2021), Jeffrey et al. (2019, 2021, 2023), Kohl et al. (2019), Machacova et al. (2021a,b, 2023), Megonigal et al. (2020), Pangala et al. (2013, 2014), Pitz & Megonigal (2017), Plain et al. (2019), Putkinen et al. (2021), Sjögersten et al. (2020), Takahashi et al. (2022), Tenhovirta et al. (2022), Wang et al. (2016), and Yip et al. (2018). Access the Virtual Issue at www.newphytologist.com/virtualissues. [ABSTRACT FROM AUTHOR]

Summary: Light intensity and quality influence photosynthesis directly but also have an indirect effect by increasing stomatal apertures and enhancing gas exchange. Consequently, in areas such as the upper canopy, a high water demand for transpiration and temperature regulation is created. This paper explores how light intensity and the natural high Blue‐Light (BL) : Red‐Light (RL) ratio in these areas, is important for controlling leaf hydraulic conductance (Kleaf) by BL signal transduction, increasing water permeability in cells surrounding the vascular tissue, in supporting the enormous water demands. Conversely, shaded inner‐canopy areas receive less radiation, have lower water and cooling demands, and exhibit reduced Kleaf due to diminished intensity and BL induction. Intriguingly, shaded leaves display higher water‐use efficiency (compared with upper‐canopy) due to decreased transpiration and cooling requirements while the presence of RL supports photosynthesis. [ABSTRACT FROM AUTHOR]

Antony N. Dodd is a plant scientist who is interested in chronobiology and circadian rhythms. He was inspired to study plant biology after attending lectures by Howard Griffiths, which showed how biochemical processes in plants could be studied over 24-hour cycles. Dodd pursued a career in research because he was fascinated by the control of daily cycles of Crassulacean acid metabolism in plants. He is motivated by the social element of science and the interactions with his research group and colleagues. Dodd provides advice for scientists, such as investing time to get things right, not only chasing big papers, and being collegial. He also discusses his favorite New Phytologist papers, which explore the use of chemical biology to study circadian rhythms in plants. Dodd mentions two favorite plant species, Agave americana and Aegagropila linnaei, and their significance in his research. [Extracted from the article]

Yoselin Benitez Alfonso, a professor in interdisciplinary plant sciences at the University of Leeds, shares her journey and passion for plant science. Growing up in Cuba, she developed a love for nature and later pursued a degree in chemistry in Spain. Despite not having a biology background, she taught herself plant biology and became interested in plasmodesmata research. She is motivated by her love for research, the success of her students, and the impact of her contributions to teaching and diversity. She considers her father and various mentors as role models and enjoys reading papers on plasmodesmata research and plant symbiosis. Her favorite plant is the olive tree due to its symbolism, climate resilience, and economic significance. Yoselin is also involved in the Black in Plant Science Network and has received recognition for her leadership and academic achievements. [Extracted from the article]

Silke Robatzek, a Heisenberg Professor at Ludwig-Maximilian-University in Munich, Germany, discusses her interest in plant science and her decision to pursue a career in research. She is motivated by her curiosity and a desire to contribute to society through discovering new knowledge. Robatzek also highlights the importance of mentors and role models in her career, and she mentions her favorite papers from the New Phytologist journal. She expresses her fascination with olive trees and their genetic diversity in terms of plant immunity. [Extracted from the article]

Summary: Cellulose is an essential component of plant cell walls and an economically important source of food, paper, textiles, and biofuel. Despite its economic and biological significance, the regulation of cellulose biosynthesis is poorly understood. Phosphorylation and dephosphorylation of cellulose synthases (CESAs) were shown to impact the direction and velocity of cellulose synthase complexes (CSCs). However, the protein kinases that phosphorylate CESAs are largely unknown. We conducted research in Arabidopsis thaliana to reveal protein kinases that phosphorylate CESAs.In this study, we used yeast two‐hybrid, protein biochemistry, genetics, and live‐cell imaging to reveal the role of calcium‐dependent protein kinase32 (CPK32) in the regulation of cellulose biosynthesis in A. thaliana.We identified CPK32 using CESA3 as a bait in a yeast two‐hybrid assay. We showed that CPK32 phosphorylates CESA3 while it interacts with both CESA1 and CESA3. Overexpressing functionally defective CPK32 variant and phospho‐dead mutation of CESA3 led to decreased motility of CSCs and reduced crystalline cellulose content in etiolated seedlings. Deregulation of CPKs impacted the stability of CSCs.We uncovered a new function of CPKs that regulates cellulose biosynthesis and a novel mechanism by which phosphorylation regulates the stability of CSCs. [ABSTRACT FROM AUTHOR]

Summary: A surge of papers have reported low leaf vulnerability to xylem embolism during drought. Here, we focus on the less studied, and more sensitive, outside‐xylem leaf hydraulic responses to multiple internal and external conditions. Studies of 34 species have resolved substantial vulnerability to dehydration of the outside‐xylem pathways, and studies of leaf hydraulic responses to light also implicate dynamic outside‐xylem responses. Detailed experiments suggest these dynamic responses arise at least in part from strong control of radial water movement across the vein bundle sheath. While leaf xylem vulnerability may influence leaf and plant survival during extreme drought, outside‐xylem dynamic responses are important for the control and resilience of water transport and leaf water status for gas exchange and growth. [ABSTRACT FROM AUTHOR]

Summary: Seminal scientific papers positing that mycorrhizal fungal networks can distribute carbon (C) among plants have stimulated a popular narrative that overstory trees, or 'mother trees', support the growth of seedlings in this way. This narrative has far‐reaching implications for our understanding of forest ecology and has been controversial in the scientific community. We review the current understanding of ectomycorrhizal C metabolism and observations on forest regeneration that make the mother tree narrative debatable. We then re‐examine data and conclusions from publications that underlie the mother tree hypothesis. Isotopic labeling methods are uniquely suited for studying element fluxes through ecosystems, but the complexity of mycorrhizal symbiosis, low detection limits, and small carbon discrimination in biological processes can cause researchers to make important inferences based on miniscule shifts in isotopic abundance, which can be misleading. We conclude that evidence of a significant net C transfer via common mycorrhizal networks that benefits the recipients is still lacking. Furthermore, a role for fungi as a C pipeline between trees is difficult to reconcile with any adaptive advantages for the fungi. Finally, the hypothesis is neither supported by boreal forest regeneration patterns nor consistent with the understanding of physiological mechanisms controlling mycorrhizal symbiosis. [ABSTRACT FROM AUTHOR]

In addition to studies on central carbon and whole plant metabolism, with isotopes, investigations into lipid metabolism are also an important focus and greatly intrigue me. Carbon assimilation, carbon partitioning, central carbon metabolism, isotope labeling, lipid metabolism, metabolic flux analysis, spatiotemporal metabolism, emergent properties Therefore, it should not be too surprising that the papers I mention here emphasize dynamic central carbon or lipid metabolism or whole plant metabolism unveiled using isotopes, by some excellent scientists in the field. Keywords: carbon assimilation; carbon partitioning; central carbon metabolism; emergent properties; isotope labeling; lipid metabolism; metabolic flux analysis; spatiotemporal metabolism EN carbon assimilation carbon partitioning central carbon metabolism emergent properties isotope labeling lipid metabolism metabolic flux analysis spatiotemporal metabolism 710 713 4 01/09/23 20230201 NES 230201 What inspired your interest in plant science?. [Extracted from the article]

This article is an Editorial to the Virtual issue on 'Remote sensing' that includes the following papers Chavana‐Bryant et al. (2017), Coupel‐Ledru et al. (2022), Cushman & Machado (2020), Disney (2019), D'Odorico et al. (2020), Dong et al. (2022), Fischer et al. (2019), Gamon et al. (2023), Gu et al. (2019), Guillemot et al. (2020), Jucker (2021), Koh et al. (2022), Konings et al. (2019), Kothari et al. (2023), Martini et al. (2022), Richardson (2019), Santini et al. (2021), Schimel et al. (2019), Serbin et al. (2019), Smith et al. (2019, 2020), Still et al. (2021), Stovall et al. (2021), Wang et al. (2020), Wong et al. (2020), Wu et al. (2021), Wu et al. (2017), Wu et al. (2018), Wu et al. (2019), Xu et al. (2021), Yan et al. (2021). Access the Virtual Issue at www.newphytologist.com/virtualissues. [ABSTRACT FROM AUTHOR]

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This document is an interview with Debora Gasperini, a researcher in plant science. Gasperini explains that her interest in research began at a young age, inspired by her love for the natural world and engaging science classes. She chose to study molecular biology and became fascinated with plants due to their unique communication and resilience. Gasperini is motivated by the thrill of discovery and problem-solving, and she considers scientists like Rita Levi-Montalcini and Katherine Esau as role models for their passion and perseverance. She also discusses her favorite papers from the journal New Phytologist, which covers a wide range of plant science topics. Gasperini appreciates the adaptability and enduring nature of plants, which continue to inspire her research. [Extracted from the article]

This document is an interview with Ari Sadanandom, a Professor of Plant Molecular Sciences at the University of Durham. Sadanandom discusses his interest in plant science, his decision to pursue a career in research, and his motivations as a scientist. He also mentions his role models and inspirations throughout his career. Additionally, Sadanandom highlights some of his favorite papers from the journal New Phytologist, focusing on topics such as plant immunity, root development, and protein modifications. Finally, he shares his favorite plant, the Mimosa plant, and provides information about his research on protein modifications and its implications for agriculture. [Extracted from the article]

Alison Smith, a Professor of Plant Biochemistry at the University of Cambridge, discusses her interest in plant science and her career in research. She explains that her fascination with the productivity of gardening as a child led her to study Biochemistry in university and eventually specialize in photosynthetic organisms. Smith finds motivation in working with students and postdocs, as well as in the endless fascination of scientific discoveries. She also mentions several mentors and colleagues who have influenced her, including notable women plant scientists. Smith appreciates the variety of topics covered in the journal New Phytologist and highlights some of her favorite papers. Finally, she shares her favorite plant, the rose, for its showiness, and her favorite photosynthetic organisms, microalgae, for their diversity and potential in biotechnology. [Extracted from the article]

Summary: If trees minimize self‐shading, new foliage in shaded parts of the crown should remain minimal. However, many species have abundant foliage on short shoots inside their crown. In this paper, we test the hypothesis that short shoots allow trees to densify their foliage in self‐shaded parts of the crown thanks to reduced costs.Using 30 woody species in Mediterranean and tropical biomes, we estimated the contribution of short shoots to total plant foliage, calculated their costs relative to long shoots including wood cost and used 3D plant simulations calibrated with field measurements to quantify their light interception, self‐shading and yield.In species with short shoots, leaves on short shoots account for the majority of leaf area. The reduced cost of short stems enables the production of leaf area with 36% less biomass. Simulations show that although short shoots are more self‐shaded, they benefit the plant because they cost less. Lastly, the morphological properties of short shoots have major implications for whole plant architecture.Taken together, our results question the validity of only assessing leaf costs to understand leaf economics and call for more integrated observations at the crown scale to understand light capture strategies in woody plants. [ABSTRACT FROM AUTHOR]

Summary: Leaf phosphorus (P) comprises four major fractions: inorganic phosphate (Pi), nucleic acids, phospholipids, P‐containing metabolites and a residual fraction. In this review paper, we investigated whether allocation of P fractions varies among groups of terrestrial vascular plants, and is indicative of a species' strategy to use P efficiently. We found that as leaf total P concentration increases, the Pi fraction increases the most, without a plateau, while other fractions plateau. Variability of the concentrations of leaf P fractions is greatest among families > species(family) > regions > plant life forms. The percentage of total P allocated to nucleic acid‐P (20–35%) and lipid‐P (14–34%) varies less among families/species. High photosynthetic P‐use efficiency is associated with low concentrations of all P fractions, and preferential allocation of P to metabolite‐P and mesophyll cells. Sequential resorption of P from senescing leaves starts with Pi, followed by metabolite‐P, and then other organic P fractions. Allocation of P to leaf P fractions varies with season. Leaf phytate concentrations vary considerably among species, associated with variation in photosynthesis and defence. Plasticity of P allocation to its fractions is important for acclimation to low soil P availability, and species‐specific P allocation is needed for co‐occurrence with other species. [ABSTRACT FROM AUTHOR]

Summary: Leaf structure plays an important role in photosynthesis. However, the causal relationship and the quantitative importance of any single structural parameter to the overall photosynthetic performance of a leaf remains open to debate. In this paper, we report on a mechanistic model, eLeaf, which successfully captures rice leaf photosynthetic performance under varying environmental conditions of light and CO2.We developed a 3D reaction‐diffusion model for leaf photosynthesis parameterised using a range of imaging data and biochemical measurements from plants grown under ambient and elevated CO2 and then interrogated the model to quantify the importance of these elements.The model successfully captured leaf‐level photosynthetic performance in rice. Photosynthetic metabolism underpinned the majority of the increased carbon assimilation rate observed under elevated CO2 levels, with a range of structural elements making positive and negative contributions. Mesophyll porosity could be varied without any major outcome on photosynthetic performance, providing a theoretical underpinning for experimental data.eLeaf allows quantitative analysis of the influence of morphological and biochemical properties on leaf photosynthesis. The analysis highlights a degree of leaf structural plasticity with respect to photosynthesis of significance in the context of attempts to improve crop photosynthesis. [ABSTRACT FROM AUTHOR]

The article discusses a comment made by Bourke et al. regarding the method described in Chen et al.'s paper on mapping quantitative trait loci (QTL) in autotetraploids. Chen et al. argue that their comment is correct based on facts and statistical principles. They explain that the method used in Bourke et al.'s paper lacks an essential component, which is genetic linkage analysis between QTLs and surrounding markers for QTL mapping in an outbred autotetraploid segregating population. Chen et al. also address the terminology and methodology used by Bourke et al., pointing out inconsistencies and inaccuracies. They conclude that their own method enables QTL mapping in autotetraploid species under a novel tetrasomic inheritance model and is based on rigorous scientific and statistical principles. [Extracted from the article]

This document is an interview with Gwyneth Ingram, a plant scientist, published in the New Phytologist journal. Ingram discusses her interest in plant science, her decision to pursue a career in research, her motivation on a day-to-day basis, and her role models. She also mentions her favorite papers from the journal, which focus on topics such as cuticle architecture, metabolic imaging, and guard cells in fern stomata. Additionally, Ingram shares her favorite plant, the medlar, and provides a brief overview of her educational and professional background. [Extracted from the article]

Dr. Steven H. Strauss, a University Distinguished Professor of Forest Biotechnology at Oregon State University, discusses his interest in plant science and his motivation to pursue a career in research. He credits his mentors during his PhD at the University of California at Berkeley for being his role models. Dr. Strauss highlights some of his favorite papers from the New Phytologist journal, including one on the genetic variation in amenability to genetic transformation and regeneration, another on the determination of crown phenology in quaking aspen, and a third on lignin modification in poplar. He also expresses his fondness for poplars, especially aspens and cottonwoods, due to their beauty and amenability to biotech methods. [Extracted from the article]

I saw the huge amount of work that went into the Arabidopsis genome whilst I was a postdoc, and now my students are assembling genomes as part of their PhDs. Keywords: bioinformatics; plant genomes; plant speciation; Profile; speciation genetics EN bioinformatics plant genomes plant speciation Profile speciation genetics 1505 1507 3 02/06/23 20230301 NES 230301 What inspired your interest in plant science? Plant genomes, bioinformatics, plant speciation, Profile, speciation genetics. [Extracted from the article]

Tessa joined New Phytologist as an Advisor in 2022.For more information on Tessa, visit https://www.danforthcenter.org/our-work/principal-investigators/tessa-burch-smith/ ORCID: Tessa Burch-Smith https://orcid.org/0000-0002-5994-4343 Why did you decide to pursue a career in research? One recent I New Phytologist i paper that I enjoyed was 'Structural and functional relationships between plasmodesmata and plant endoplasmic reticulum-plasma membrane contact sites consisting of three synaptotagmins' (Ishikawa I et al i ., 2020) from the Shimada group. Keywords: intercellular trafficking; microscopy; Nicotiana benthamiana; plant viruses; plasmodesmata EN intercellular trafficking microscopy Nicotiana benthamiana plant viruses plasmodesmata 2155 2157 3 08/22/22 20220915 NES 220915 What inspired your interest in plant science?. [Extracted from the article]

His research chiefly focuses on identifying and characterising new factors involved in the regulation of anthocyanin biosynthesis during high light acclimation. Keywords: acclimation; anthocyanin; early career researcher; flavonoid biosynthesis; high light; Profile; retrograde signalling; stress response EN acclimation anthocyanin early career researcher flavonoid biosynthesis high light Profile retrograde signalling stress response 2016 2018 3 11/21/22 20221215 NES 221215 Galileo Estopare Araguirang's poster 'When plants paint their leaves purple: analyses of new factors involved in the regulation of anthocyanin biosynthesis in Arabidopsis during high light' won first prize at the Next Generations Scientists meeting 2022 in Tartu, Estonia. Under the supervision of Professor Dr Alfred Batschauer, he carried out his MSc thesis on the photobiochemistry of a cryptochrome 2 mutant at Philipps-Universität Marburg, Germany (2017). Anthocyanin, early career researcher, acclimation, Profile, stress response, flavonoid biosynthesis, high light, retrograde signalling. [Extracted from the article]

Biodiversity, community ecology, global change, plant traits, plant-microbe interactions (b) Campanula scheuchzeri in the forefield of the Ödenwinkel glacier in Austria; this is one of the few plant species that occurs along the whole successional gradient, and thus became a model species in our laboratory to test successional processes. gl References 1 E-Vojtkó A, Junker RR, de Bello F, Götzenberger L. 2022. Keywords: biodiversity; community ecology; global change; plant traits; plant-microbe interactions EN biodiversity community ecology global change plant traits plant-microbe interactions 1634 1636 3 11/07/22 20221201 NES 221201 What inspired your interest in plant science?. [Extracted from the article]

People often forget that Dan's PhD work on plant-ants and ant-plants was really very botanical, especially in the modern sense of working on plant-animal interactions. Keywords: adaptive accuracy; comparative biology; Dalechampia; euglossine bees; floral evolution; natural selection; pollination EN adaptive accuracy comparative biology Dalechampia euglossine bees floral evolution natural selection pollination 21 23 3 09/12/22 20221001 NES 221001 What inspired your interest in plant science? I took a few plant courses at UC Santa Barbara towards the end of my undergraduate career just to "learn insect food plants" and quickly came to appreciate plants in their own right. [Extracted from the article]

Summary: Improving photosynthetic efficiency has recently emerged as a promising way to increase crop production in a sustainable manner. While chloroplast size may affect photosynthetic efficiency in several ways, we aimed to explore whether chloroplast size manipulation can be a viable approach to improving photosynthetic performance.Several tobacco (Nicotiana tabacum) lines with contrasting chloroplast sizes were generated via manipulation of chloroplast division genes to assess photosynthetic performance under steady‐state and fluctuating light. A selection of lines was included in a field trial to explore productivity.Lines with enlarged chloroplasts underperformed in most of the measured traits. Lines with smaller and more numerous chloroplasts showed a similar efficiency compared with wild‐type (WT) tobacco. Chloroplast size only weakly affected light absorptance and light profiles within the leaf. Increasing chloroplast size decreased mesophyll conductance (gm) but decreased chloroplast size did not increase gm. Increasing chloroplast size reduced chloroplast movements and enhanced non‐photochemical quenching. The chloroplast smaller than WT appeared to be no better than WT for photosynthetic efficiency and productivity under field conditions.The results indicate that chloroplast size manipulations are therefore unlikely to lead to higher photosynthetic efficiency or growth. [ABSTRACT FROM AUTHOR]

Summary: Karyological characteristics are among the traits underpinning the invasion success of vascular plants.Using 11 049 species, we tested the effects of genome size and ploidy levels on plant naturalization (species forming self‐sustaining populations where they are not native) and invasion (naturalized species spreading rapidly and having environmental impact).The probability that a species naturalized anywhere in the world decreased with increasing monoploid genome size (DNA content of a single chromosome set). Naturalized or invasive species with intermediate monoploid genomes were reported from many regions, but those with either small or large genomes occurred in fewer regions. By contrast, large holoploid genome sizes (DNA content of the unreplicated gametic nucleus) constrained naturalization but favoured invasion.We suggest that a small genome is an advantage during naturalization, being linked to traits favouring adaptation to local conditions, but for invasive spread, traits associated with a large holoploid genome, where the impact of polyploidy may act, facilitate long‐distance dispersal and competition with other species. [ABSTRACT FROM AUTHOR]

Summary: Frequent observations of higher mortality in larger trees than in smaller ones during droughts have sparked an increasing interest in size‐dependent drought‐induced mortality. However, the underlying physiological mechanisms are not well understood, with height‐associated hydraulic constraints often being implied as the potential mechanism driving increased drought vulnerability. We performed a quantitative synthesis on how key traits that drive plant water and carbon economy change with tree height within species and assessed the implications that the different constraints and compensations may have on the interacting mechanisms (hydraulic failure, carbon starvation and/or biotic‐agent attacks) affecting tree vulnerability to drought. While xylem tension increases with tree height, taller trees present a range of structural and functional adjustments, including more efficient water use and transport and greater water uptake and storage capacity, that mitigate the path‐length‐associated drop in water potential. These adaptations allow taller trees to withstand episodic water stress. Conclusive evidence for height‐dependent increased vulnerability to hydraulic failure and carbon starvation, and their coupling to defence mechanisms and pest and pathogen dynamics, is still lacking. Further research is needed, particularly at the intraspecific level, to ascertain the specific conditions and thresholds above which height hinders tree survival under drought. [ABSTRACT FROM AUTHOR]

Summary: Terrestrial CAM plants typically occur in hot semiarid regions, yet can show high crop productivity under favorable conditions.To achieve a more mechanistic understanding of CAM plant productivity, a biochemical model of diel metabolism was developed and integrated with 3‐D shoot morphology to predict the energetics of light interception and photosynthetic carbon assimilation.Using Agave tequilana as an example, this biochemical model faithfully simulated the four diel phases of CO2 and metabolite dynamics during the CAM rhythm. After capturing the 3‐D form over an 8‐yr production cycle, a ray‐tracing method allowed the prediction of the light microclimate across all photosynthetic surfaces. Integration with the biochemical model thereby enabled the simulation of plant and stand carbon uptake over daily and annual courses.The theoretical maximum energy conversion efficiency of Agave spp. is calculated at 0.045–0.049, up to 7% higher than for C3 photosynthesis. Actual light interception, and biochemical and anatomical limitations, reduced this to 0.0069, or 15.6 Mg ha−1 yr−1 dry mass annualized over an 8‐yr cropping cycle, consistent with observation. This is comparable to the productivity of many C3 crops, demonstrating the potential of CAM plants in climates where little else may be grown while indicating strategies that could raise their productivity. [ABSTRACT FROM AUTHOR]

Summary: The mechanisms underlying trait conservation over long evolutionary time scales are poorly known. These mechanisms fall into the two broad and nonmutually exclusive categories of constraint and selection. A variety of factors have been hypothesized to constrain trait evolution. Alternatively, selection can maintain similar trait values across many species if the causes of selection are also relatively conserved, while many sources of constraint may be overcome over longer periods of evolutionary divergence. An example of deep trait conservation is tetradynamy in the large family Brassicaceae, where the four medial stamens are longer than the two lateral stamens. Previous work has found selection to maintain this difference in lengths, which we call anther separation, in wild radish, Raphanus raphanistrum.Here, we test the constraint hypothesis using five generations of artificial selection to reduce anther separation in wild radish.We found a rapid linear response to this selection, with no evidence for depletion of genetic variation and correlated responses to this selection in only four of 15 other traits, suggesting a lack of strong constraint.Taken together, available evidence suggests that tetradynamy is likely to be conserved due to selection, but the function of this trait remains unclear. [ABSTRACT FROM AUTHOR]

Summary: Jasmonate (JA) re‐programs metabolism to confer resistance to diverse environmental threats. Jasmonate stimulates the degradation of JASMONATE ZIM‐DOMAIN (JAZ) proteins that repress the activity of MYC transcription factors. In Arabidopsis thaliana, MYC and JAZ are encoded by 4 and 13 genes, respectively. The extent to which expansion of the MYC and JAZ families has contributed to functional diversification of JA responses is not well understood.Here, we investigated the role of MYC and JAZ paralogs in controlling the production of defense compounds derived from aromatic amino acids (AAAs).Analysis of loss‐of‐function and dominant myc mutations identified MYC3 and MYC4 as the major regulators of JA‐induced tryptophan metabolism. We developed a JAZ family‐based, forward genetics approach to screen randomized jaz polymutants for allelic combinations that enhance tryptophan biosynthetic capacity. We found that mutants defective in all members (JAZ1/2/5/6) of JAZ group I over‐accumulate AAA‐derived defense compounds, constitutively express marker genes for the JA–ethylene branch of immunity and are more resistant to necrotrophic pathogens but not insect herbivores.In defining JAZ and MYC paralogs that regulate the production of amino‐acid‐derived defense compounds, our results provide insight into the specificity of JA signaling in immunity. [ABSTRACT FROM AUTHOR]

Summary: Telomerase, telomeric DNA and associated proteins together represent a complex, finely tuned and functionally conserved mechanism that ensures genome integrity by protecting and maintaining chromosome ends. Changes in its components can threaten an organism's viability. Nevertheless, molecular innovation in telomere maintenance has occurred multiple times during eukaryote evolution, giving rise to species/taxa with unusual telomeric DNA sequences, telomerase components or telomerase‐independent telomere maintenance. The central component of telomere maintenance machinery is telomerase RNA (TR) as it templates telomere DNA synthesis, its mutation can change telomere DNA and disrupt its recognition by telomere proteins, thereby leading to collapse of their end‐protective and telomerase recruitment functions.Using a combination of bioinformatic and experimental approaches, we examine a plausible scenario of evolutionary changes in TR underlying telomere transitions.We identified plants harbouring multiple TR paralogs whose template regions could support the synthesis of diverse telomeres. In our hypothesis, formation of unusual telomeres is associated with the occurrence of TR paralogs that can accumulate mutations, and through their functional redundancy, allow for the adaptive evolution of the other telomere components.Experimental analyses of telomeres in the examined plants demonstrate evolutionary telomere transitions corresponding to TR paralogs with diverse template regions. [ABSTRACT FROM AUTHOR]

Summary: Carotenoids are photoprotectant pigments and precursors of hormones such as strigolactones (SL). Carotenoids are produced in plastids from geranylgeranyl diphosphate (GGPP), which is diverted to the carotenoid pathway by phytoene synthase (PSY). In tomato (Solanum lycopersicum), three genes encode plastid‐targeted GGPP synthases (SlG1 to SlG3) and three genes encode PSY isoforms (PSY1 to PSY3).Here, we investigated the function of SlG1 by generating loss‐of‐function lines and combining their metabolic and physiological phenotyping with gene co‐expression and co‐immunoprecipitation analyses.Leaves and fruits of slg1 lines showed a wild‐type phenotype in terms of carotenoid accumulation, photosynthesis, and development under normal growth conditions. In response to bacterial infection, however, slg1 leaves produced lower levels of defensive GGPP‐derived diterpenoids. In roots, SlG1 was co‐expressed with PSY3 and other genes involved in SL production, and slg1 lines grown under phosphate starvation exuded less SLs. However, slg1 plants did not display the branched shoot phenotype observed in other SL‐defective mutants. At the protein level, SlG1 physically interacted with the root‐specific PSY3 isoform but not with PSY1 and PSY2.Our results confirm specific roles for SlG1 in producing GGPP for defensive diterpenoids in leaves and carotenoid‐derived SLs (in combination with PSY3) in roots. [ABSTRACT FROM AUTHOR]

C-terminal conformational changes in SCF-D3/MAX2 ubiquitin ligase are required for KAI2-mediated signaling Our I in silico i analyses of KAI2 recruitment by MAX2-CTH show high sequence conservation between 200 KAI2 and D14 sequences both in the engaged and the CTH-dislodged states of MAX2. (e, g) Residues involved in forming the D14/KAI2-MAX2-CTH interface are colored on KAI2 surface by amino acid conservation across 200 KAI2/ D14 sequences (left). Keywords: KAI2; karrikin; MAX2; plant hormones; signaling; strigolactone; ubiquitin ligase EN KAI2 karrikin MAX2 plant hormones signaling strigolactone ubiquitin ligase 2067 2075 9 08/23/23 20230915 NES 230915 Data availability The data that support the findings of this study are available in the Supporting Information of this article. [Extracted from the article]

Summary: Heterogeneity in gene trees, morphological characters, and composition has been associated with several major plant clades. Here, we examine heterogeneity in composition across a large transcriptomic dataset of plants to better understand whether locations of shifts in composition are shared across gene regions and whether directions of shifts within clades are shared across gene regions.We estimate mixed models of composition for both nucleotide and amino acids across a recent large‐scale transcriptomic dataset for plants.We find shifts in composition across both nucleotide and amino acid datasets, with more shifts detected in nucleotides. We find that Chlorophytes and lineages within experience the most shifts. However, many shifts occur at the origins of land, vascular, and seed plants. While genes in these clades do not typically share the same composition, they tend to shift in the same direction. We discuss potential causes of these patterns.Compositional heterogeneity has been highlighted as a potential problem for phylogenetic analysis, but the variation presented here highlights the need to further investigate these patterns for the signal of biological processes. [ABSTRACT FROM AUTHOR]

Summary: Rhizomicrobiome plays important roles in plant growth and health, contributing to the sustainable development of agriculture. Plants recruit and assemble the rhizomicrobiome to satisfy their functional requirements, which is widely recognized as the 'cry for help' theory, but the intrinsic mechanisms are still limited.In this study, we revealed a novel mechanism by which plants reprogram the functional expression of inhabited rhizobacteria, in addition to the de novo recruitment of soil microbes, to satisfy different functional requirements as plants grow. This might be an efficient and low‐cost strategy and a substantial extension to the rhizomicrobiome recruitment theory.We found that the plant regulated the sequential expression of genes related to biocontrol and plant growth promotion in two well‐studied rhizobacteria Bacillus velezensis SQR9 and Pseudomonas protegens CHA0 through root exudate succession across the plant developmental stages. Sixteen key chemicals in root exudates were identified to significantly regulate the rhizobacterial functional gene expression by high‐throughput qPCR.This study not only deepens our understanding of the interaction between the plant–rhizosphere microbiome, but also provides a novel strategy to regulate and balance the different functional expression of the rhizomicrobiome to improve plant health and growth. [ABSTRACT FROM AUTHOR]

Summary: BAK1‐INTERACTING RECEPTOR LIKE KINASE1 (BIR1) is a negative regulator of various aspects of disease resistance and immune responses.Here, we investigated the functional role of soybean (Glycine max) BIR1 (GmBIR1) during soybean interaction with soybean cyst nematode (SCN, Heterodera glycines) and the molecular mechanism through which GmBIR1 regulates plant immunity.Overexpression of wild‐type variant of GmBIR1 (WT‐GmBIR1) using transgenic soybean hairy roots significantly increased soybean susceptibility to SCN, whereas overexpression of kinase‐dead variant (KD‐GmBIR1) significantly increased plant resistance. Transcriptome analysis revealed that genes oppositely regulated in WT‐GmBIR1 and KD‐GmBIR1 upon SCN infection were enriched primarily in defense and immunity‐related functions. Quantitative phosphoproteomic analysis identified 208 proteins as putative substrates of the GmBIR1 signaling pathway, 114 of which were differentially phosphorylated upon SCN infection. In addition, the phosphoproteomic data pointed to a role of the GmBIR1 signaling pathway in regulating alternative pre‐mRNA splicing. Genome‐wide analysis of splicing events provided compelling evidence supporting a role of the GmBIR1 signaling pathway in establishing alternative splicing during SCN infection.Our results provide novel mechanistic insights into the function of the GmBIR1 signaling pathway in regulating soybean transcriptome and spliceome via differential phosphorylation of splicing factors and regulation of splicing events of pre‐mRNA decay‐ and spliceosome‐related genes. [ABSTRACT FROM AUTHOR]

Summary: Biotic and abiotic interactions shape natural microbial communities. The mechanisms behind microbe–microbe interactions, particularly those protein based, are not well understood. We hypothesize that released proteins with antimicrobial activity are a powerful and highly specific toolset to shape and defend plant niches.We have studied Albugo candida, an obligate plant parasite from the protist Oomycota phylum, for its potential to modulate the growth of bacteria through release of antimicrobial proteins into the apoplast.Amplicon sequencing and network analysis of Albugo‐infected and uninfected wild Arabidopsis thaliana samples revealed an abundance of negative correlations between Albugo and other phyllosphere microbes. Analysis of the apoplastic proteome of Albugo‐colonized leaves combined with machine learning predictors enabled the selection of antimicrobial candidates for heterologous expression and study of their inhibitory function. We found for three candidate proteins selective antimicrobial activity against Gram‐positive bacteria isolated from A. thaliana and demonstrate that these inhibited bacteria are precisely important for the stability of the community structure. We could ascribe the antibacterial activity of the candidates to intrinsically disordered regions and positively correlate it with their net charge.This is the first report of protist proteins with antimicrobial activity under apoplastic conditions that therefore are potential biocontrol tools for targeted manipulation of the microbiome. See also the Commentary on this article by Rovenich & Thomma, 239: 2064–2066. [ABSTRACT FROM AUTHOR]

Summary: Nitrogen (N) fertilization increases biomass and soil organic carbon (SOC) accumulation in boreal pine forests, but the underlying mechanisms remain uncertain. At two Scots pine sites, one undergoing annual N fertilization and the other a reference, we sought to explain these responses.We measured component fluxes, including biomass production, SOC accumulation, and respiration, and summed them into carbon budgets. We compared the resulting summations to ecosystem fluxes measured by eddy covariance.N fertilization increased most component fluxes (P < 0.05), especially SOC accumulation (20×). Only fine‐root, mycorrhiza, and exudate production decreased, by 237 (SD = 28) g C m−2 yr−1. Stemwood production increases were ascribed to this partitioning shift, gross primary production (GPP), and carbon‐use efficiency, in that order. The methods agreed in their estimates of GPP in both stands (P > 0.05), but the components detected an increase in net ecosystem production (NEP) (190 (54) g C m−2 yr−1; P < 0.01) that eddy covariance did not (19 (62) g C m−2 yr−1; ns).The pairing of plots, the simplicity of the sites, and the strength of response provide a compelling description of N effects on the C budget. However, the disagreement between methods calls for further paired tests of N fertilization effects in simple forest ecosystems. See also the Commentary on this article by Ryan, 239: 2060–2063. [ABSTRACT FROM AUTHOR]

Summary: Urbanization can affect the timing of plant reproduction (i.e. flowering and fruiting) and associated ecosystem processes. However, our knowledge of how plant phenology responds to urbanization and its associated environmental changes is limited.Herbaria represent an important, but underutilized source of data for investigating this question. We harnessed phenological data from herbarium specimens representing 200 plant species collected across 120 yr from the eastern US to investigate the spatiotemporal effects of urbanization on flowering and fruiting phenology and frost risk (i.e. time between the last frost date and flowering).Effects of urbanization on plant reproductive phenology varied significantly in direction and magnitude across species ranges. Increased urbanization led to earlier flowering in colder and wetter regions and delayed fruiting in regions with wetter spring conditions. Frost risk was elevated with increased urbanization in regions with colder and wetter spring conditions.Our study demonstrates that predictions of phenological change and its associated impacts must account for both climatic and human effects, which are context dependent and do not necessarily coincide. We must move beyond phenological models that only incorporate temperature variables and consider multiple environmental factors and their interactions when estimating plant phenology, especially at larger spatial and taxonomic scales. See also the Commentary on this article by Zhu & Song, 239: 2057–2059. [ABSTRACT FROM AUTHOR]

Summary: The continuous imbalance between nitrogen (N) and phosphorus (P) deposition is expected to shift many ecosystems from N‐ to P limitation. Extraradical hyphae of ectomycorrhizal (ECM) fungi play important roles in plant nutrient acquisition under nutrient deficiency. However, whether and how ECM hyphae enhance soil P availability to alleviate N‐induced P deficiency remains unclear.We investigated the impacts of ECM hyphae on transformations among different soil P fractions and underlying mechanisms under N deposition in two ECM‐dominated forests.Ectomycorrhizal hyphae enhanced soil P availability under N addition by stimulating mineralization of organic P (Po) and desorption and solubilization of secondary mineral P, as indicated by N‐induced increase in positive hyphal effect on plant‐available P pool and negative hyphal effects on Po and secondary mineral P pools. Moreover, ECM hyphae increased soil phosphatase activity and abundance of microbial genes associated with Po mineralization and inorganic P solubilization, while decreasing concentrations of Fe/Al oxides.Our results suggest that ECM hyphae can alleviate N‐induced P deficiency in ECM‐dominated forests by regulating interactions between microbial and abiotic factors involved in soil P transformations. This advances our understanding of plant acclimation strategies via mediating plant–mycorrhiza interactions to sustain forest production and functional stability under changing environments. [ABSTRACT FROM AUTHOR]

Summary: The application of the CRISPR/Cas system as a biotechnological tool for genome editing has revolutionized plant biology. Recently, the repertoire was expanded by CRISPR‐Kill, enabling CRISPR/Cas‐mediated tissue engineering through genome elimination by tissue‐specific expression.Using the Cas9 nuclease from Staphylococcus aureus (SaCas9), CRISPR‐Kill relies on the induction of multiple double‐strand breaks (DSBs) in conserved repetitive genome regions, such as the rDNA, causing cell death of the targeted cells. Here, we show that in addition to spatial control by tissue‐specific expression, temporal control of CRISPR‐mediated cell death is feasible in Arabidopsis thaliana.We established a chemically inducible tissue‐specific CRISPR‐Kill system that allows the simultaneous detection of targeted cells by fluorescence markers. As proof of concept, we were able to eliminate lateral roots and ablate root stem cells. Moreover, using a multi-tissue promoter, we induced targeted cell death at defined time points in different organs at select developmental stages.Thus, using this system makes it possible to gain new insights into the developmental plasticity of certain cell types. In addition to enabling tissue engineering in plants, our system provides an invaluable tool to study the response of developing plant tissue to cell elimination through positional signaling and cell‐to‐cell communication. [ABSTRACT FROM AUTHOR]

Summary: Members of the R2R3‐MYB transcription factor subgroup 19 (SG19) have been extensively studied in multiple plant species using different silenced or mutated lines. Some studies have proposed a function in flower opening, others in floral organ development/maturation, or specialized metabolism production. While SG19 members are clearly key players during flower development and maturation, the resulting picture is complex, confusing our understanding in how SG19 genes function.To clarify the function of the SG19 transcription factors, we used a single system, Petunia axillaris, and targeted its two SG19 members (EOB1 and EOB2) by CRISPR‐Cas9.Although EOB1 and EOB2 are highly similar, they display radically different mutant phenotypes. EOB1 has a specific role in scent emission while EOB2 has pleiotropic functions during flower development. The eob2 knockout mutants reveal that EOB2 is a repressor of flower bud senescence by inhibiting ethylene production. Moreover, partial loss‐of‐function mutants (transcriptional activation domain missing) show that EOB2 is also involved in both petal and pistil maturation through regulation of primary and secondary metabolism.Here, we provide new insights into the genetic regulation of flower maturation and senescence. It also emphasizes the function of EOB2 in the adaptation of plants to specific guilds of pollinators. [ABSTRACT FROM AUTHOR]

Summary: In the nodules of IRLC legumes, including Medicago truncatula, nitrogen‐fixing rhizobia undergo terminal differentiation resulting in elongated and endoreduplicated bacteroids specialized for nitrogen fixation. This irreversible transition of rhizobia is mediated by host produced nodule‐specific cysteine‐rich (NCR) peptides, of which c. 700 are encoded in the M. truncatula genome but only few of them have been proved to be essential for nitrogen fixation.We carried out the characterization of the nodulation phenotype of three ineffective nitrogen‐fixing M. truncatula mutants using confocal and electron microscopy, monitored the expression of defence and senescence‐related marker genes, and analysed the bacteroid differentiation with flow cytometry. Genetic mapping combined with microarray‐ or transcriptome‐based cloning was used to identify the impaired genes.Mtsym19 and Mtsym20 mutants are defective in the same peptide NCR‐new35 and the lack of NCR343 is responsible for the ineffective symbiosis of NF‐FN9363. We found that the expression of NCR‐new35 is significantly lower and limited to the transition zone of the nodule compared with other crucial NCRs. The fluorescent protein‐tagged version of NCR343 and NCR‐new35 localized to the symbiotic compartment.Our discovery added two additional members to the group of NCR genes essential for nitrogen‐fixing symbiosis in M. truncatula. [ABSTRACT FROM AUTHOR]

Summary: Meiotic crossovers ensure accurate chromosome segregation and increase genetic diversity. RAD51C and RAD51D play an early role in facilitating RAD51 during homologous recombination. However, their later function in meiosis is largely unknown in plants.Here, through targeted disruption of RAD51C and RAD51D, we generated three new mutants and revealed their later meiotic role in crossover maturation.The rad51c‐3 and rad51d‐4 mutants showed a mixture of bivalents and univalents and no chromosomal entanglements, whereas rad51d‐5 exhibited an intermediate phenotype with reduced chromosomal entanglements and increased bivalent formation compared with knockout alleles. Comparisons of RAD51 loadings and chromosomal entanglements in these single mutants, rad51c‐3 rad51d‐4, rad51c‐3 dmc1a dmc1b, and rad51d‐4 dmc1a dmc1b suggest that the retained level of RAD51 in mutants is required for uncovering their function in crossover formation. Reductions in chiasma frequency and later HEI10 foci in these mutants support that crossover maturation requires RAD51C and RAD51D. Moreover, interaction between RAD51D and MSH5 indicates that RAD51 paralogs may cooperate with MSH5 to ensure accurate Holliday junction processing into crossover products.This finding of the role of RAD51 paralogs in crossover control may be conserved from mammals to plants and advances our current understanding of these proteins. [ABSTRACT FROM AUTHOR]

Summary: Establishment of symbiosis between plants and arbuscular mycorrhizal (AM) fungi depends on fungal chitooligosaccharides (COs) and lipo‐chitooligosaccharides (LCOs). The latter are also produced by nitrogen‐fixing rhizobia to induce nodules on leguminous roots. However, host enzymes regulating structure and levels of these signals remain largely unknown.Here, we analyzed the expression of a β‐N‐acetylhexosaminidase gene of Medicago truncatula (MtHEXO2) and biochemically characterized the enzyme. Mutant analysis was performed to study the role of MtHEXO2 during symbiosis.We found that expression of MtHEXO2 is associated with AM symbiosis and nodulation. MtHEXO2 expression in the rhizodermis was upregulated in response to applied chitotetraose, chitoheptaose, and LCOs. M. truncatula mutants deficient in symbiotic signaling did not show induction of MtHEXO2. Subcellular localization analysis indicated that MtHEXO2 is an extracellular protein. Biochemical analysis showed that recombinant MtHEXO2 does not cleave LCOs but can degrade COs into N‐acetylglucosamine (GlcNAc). Hexo2 mutants exhibited reduced colonization by AM fungi; however, nodulation was not affected in hexo2 mutants.In conclusion, we identified an enzyme, which inactivates COs and promotes the AM symbiosis. We hypothesize that GlcNAc produced by MtHEXO2 may function as a secondary symbiotic signal. [ABSTRACT FROM AUTHOR]