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Water limitations for agriculture will likely become crucial in the next decades in some regions such as the Mediterranean basin with the current climate change projections. In this context, recent evidence suggests that the application of conservation agriculture, which reduces the frequency and intensity of soil tillage, could confer a higher stability of agricultural systems against climate variability. However, not many experiments have addressed the interaction between tillage type and the resistance to drought in rainfed crops. In this work, we evaluated the resistance to drought of triticale (Triticale hexaploide L.) crops managed with different tillage systems: traditional tillage (TT), reduced tillage (RT) and no tillage (NT). A rainfall exclusion experiment was carried out in a typical wheat/legume Mediterranean rotation in SW Spain, in a long‐term experiment established in 2008 comparing the three tillage systems. Grain yield and different variables related to plant ecophysiology, root development, biomass allocation and colonisation by arbuscular mycorrhizal fungi (AMF) were evaluated over one crop cycle. Tillage type had a significant influence on soil water storage (SWS), such that soils under NT had, on average, a 16% greater SWS than soils under RT or TT. Grain yield was significantly reduced by rainfall exclusion, in particular in the TT, where drought reduced grain yield by 31%. Gas exchange data also showed that plants in the TT system were more sensitive to drought, such that maximum photosynthesis rates were reduced by 25% because of rainfall exclusion in this tillage system. Drought had a negative impact on root biomass across the three tillage systems, especially in the RT, where a reduction in the root:shoot ratio was observed. The effect of tillage on mycorrhizal colonisation was more evident than the effect of drought; in general, conservation tillage systems (RT and NT) tended to have higher values for all AMF traits compared to the TT. In summary, the NT system tended to exhibit more favourable performance in terms of soil water retention, grain yield stability under drought conditions and mycorrhizal symbiosis, which suggests enhanced resource use efficiency in this system. [ABSTRACT FROM AUTHOR]

Changes in rainfall patterns are important environmental factors affecting plant growth, especially when larger precipitation events and prolonged drought periods occur in subtropical regions. There are many studies on how drought reduces plant biomass through drought-sensitive functional traits, but how excess water affects plant growth and ecophysiology is still poorly understood. Therefore, a greenhouse experiment was conducted on Schima superba (Theaceae), a dominant tree species in subtropical forests and commonly used in forestry, in a closed chamber under control (25% soil water content (SWC) as in local forests), drought stress (D, 15% SWC) and moisture stress (W, 35% SWC). Plant growth and ecophysiological traits related to morphology, leaf gas exchange, water potential and structural traits were measured. Compared to control, S. suberba under dry conditions significantly decreased its aboveground biomass, photosynthetic rate (A), leaf water potential and nitrogen use efficiency, but increased intrinsic water use efficiency, root to shoot ratio and specific root length. S. superba under wet conditions also significantly decreased its total biomass, aboveground biomass and specific root length, while W had no effect on A and leaf water potential. Our results indicate that S. superba shows a decrease in carbon gain under drought stress, but less response under wet conditions. This emphasizes the need to consider the strength and frequency of rainfall pattern changes in future studies because rainfall may either alleviate or intensify the effects of drought stress depending on the moisture level, thus suitable water conditions is important for better management of this tree species in subtropical China. [ABSTRACT FROM AUTHOR]

Summary Understanding isotope fractionation mechanisms is fundamental for analyses of plant ecophysiology and paleoclimate based on tree‐ring isotope data. To gain new insights into isotope fractionation, we analysed intramolecular 13C discrimination in tree‐ring glucose (Δi′, i = C‐1 to C‐6) and metabolic deuterium fractionation at H1 and H2 (εmet) combinedly. This dual‐isotope approach was used for isotope‐signal deconvolution. We found evidence for metabolic processes affecting Δ1′ and Δ3′, which respond to air vapour pressure deficit (VPD), and processes affecting Δ1′, Δ2′, and εmet, which respond to precipitation but not VPD. These relationships exhibit change points dividing a period of homeostasis (1961–1980) from a period of metabolic adjustment (1983–1995). Homeostasis may result from sufficient groundwater availability. Additionally, we found Δ5′ and Δ6′ relationships with radiation and temperature, which are temporally stable and consistent with previously proposed isotope fractionation mechanisms. Based on the multitude of climate covariables, intramolecular carbon isotope analysis has a remarkable potential for climate reconstruction. While isotope fractionation beyond leaves is currently considered to be constant, we propose significant parts of the carbon and hydrogen isotope variation in tree‐ring glucose originate in stems (precipitation‐dependent signals). As basis for follow‐up studies, we propose mechanisms introducing Δ1′, Δ2′, Δ3′, and εmet variability. [ABSTRACT FROM AUTHOR]

Afforestation with native trees can enhance the conversion of degraded saline lands into productive landscapes with considerable economic and environmental benefits. To identify the native salt‐resistant species for restoration, we investigated how salinity affects the growth and water status of sapling from two Neltuma species from the Monte region. We produced Neltuma flexuosa and Neltuma chilensis saplings using seeds harvested from native forests with multiple provenances (Fiambalá, Chilecito, Mogna, Pipanaco, Talampaya, and Andalgalá). We conducted a greenhouse trial in which 810 saplings of different species/provenance combination received one of three saline irrigations, that is, sodium chloride solutions of 0.01 (no stress), 0.10 (moderate stress), and 0.25 M (severe stress). We found that Neltuma saplings exhibited varying degrees of reduction in their growth (plant height and aboveground biomass) and water status (e.g., stomatal conductance and leaf water potential) traits with increasing salt stress. N. flexuosa‐Fiambalá and N. flexuosa‐Chilecito were the most tolerant and sensitive, respectively, while all provenances of N. chilensis showed intermediate tolerance to salinity. These results suggest that N. flexuosa displays highly variable plasticity to salt stress compared to N. chilensis, emphasizing the need to select appropriate provenances for afforestation in saline‐degraded areas. [ABSTRACT FROM AUTHOR]

Terrestrial water fluxes are substantially mediated by vegetation, while the distribution, growth, health, and mortality of plants are strongly influenced by the availability of water. These interactions, playing out across multiple spatial and temporal scales, link the disciplines of plant ecophysiology and ecohydrology. Despite this connection, the disciplines have provided complementary, but largely independent, perspectives on the soil‐plant‐atmosphere continuum since their crystallization as modern scientific disciplines in the late 20th century. This review traces the development of the two disciplines, from their respective origins in engineering and ecology, their largely independent growth and maturation, and the eventual development of common conceptual and quantitative frameworks. This common ground has allowed explicit coupling of the disciplines to better understand plant function. Case studies both illuminate the limitations of the disciplines working in isolation, and reveal the exciting possibilities created by consilience between the disciplines. The histories of the two disciplines suggest opportunities for new advances will arise from sharing methodologies, working across multiple levels of complexity, and leveraging new observational technologies. Practically, these exchanges can be supported by creating shared scientific spaces. This review argues that consilience and collaboration are essential for robust and evidence‐based predictions and policy responses under global change. Summary statement: Ecophysiology and ecohydrology share an interest in plant–water interactions but have largely developed and operated along distinct paths. We review the development of these fields and difficulties that emerged and argue how greater consilience can address pressing challenges under global change. [ABSTRACT FROM AUTHOR]

Plant physiological status is the interaction between the plant genome and the prevailing growth conditions. Accurate characterization of plant physiology is, therefore, fundamental to effective plant phenotyping studies; particularly those focused on identifying traits associated with improved yield, lower input requirements, and climate resilience. Here, we outline the approaches used to assess plant physiology and how these techniques of direct empirical observations of processes such as photosynthetic CO2 assimilation, stomatal conductance, photosystem II electron transport, or the effectiveness of protective energy dissipation mechanisms are unsuited to high-throughput phenotyping applications. Novel optical sensors, remote/proximal sensing (multi- and hyperspectral reflectance, infrared thermography, sun-induced fluorescence), LiDAR, and automated analyses of below-ground development offer the possibility to infer plant physiological status and growth. However, there are limitations to such indirect approaches to gauging plant physiology. These methodologies that are appropriate for the rapid high temporal screening of a number of crop varieties over a wide spatial scale do still require calibration or validation with direct empirical measurement of plant physiological status. The use of deep-learning and artificial intelligence approaches may enable the effective synthesis of large multivariate datasets to more accurately quantify physiological characters rapidly in high numbers of replicate plants. Advances in automated data collection and subsequent data processing represent an opportunity for plant phenotyping efforts to fully integrate fundamental physiological data into vital efforts to ensure food and agro-economic sustainability.

Chlorophyll fluorescence measured at the leaf scale through pulse amplitude modulation (PAM) has provided valuable insight into photosynthesis. At the canopy- and satellite-scale, solar-induced fluorescence (SIF) provides a method to estimate the photosynthetic activity of plants across spatiotemporal scales. However, retrieving SIF signal remotely requires instruments with high spectral resolution, making it difficult and often expensive to measure canopy-level steady-state chlorophyll fluorescence under natural sunlight. Considering this, we built a novel low-cost photodiode system that retrieves far-red chlorophyll fluorescence emission induced by a blue light emitting diode (LED) light source, for 2 h at night, above the canopy. Our objective was to determine if an active remote sensing-based night-time photodiode method could track changes in canopy-scale LED-induced chlorophyll fluorescence (LEDIF) during an imposed drought on a broadleaf evergreen shrub, Polygala myrtifolia. Far-red LEDIF (720-740 nm) was retrieved using low-cost photodiodes (LEDIFphotodiode) and validated against measurements from a hyperspectral spectroradiometer (LEDIFhyperspectral). To link the LEDIF signal with physiological drought response, we tracked stomatal conductance (gsw) using a porometer, two leaf-level vegetation indices-photochemical reflectance index and normalized difference vegetation index-to represent xanthophyll and chlorophyll pigment dynamics, respectively, and a PAM fluorimeter to measure photochemical and non-photochemical dynamics. Our results demonstrate a similar performance between the photodiode and hyperspectral retrievals of LEDIF (R2 = 0.77). Furthermore, LEDIFphotodiode closely tracked drought responses associated with a decrease in photochemical quenching (R2 = 0.69), Fv/Fm (R2 = 0.59) and leaf-level photochemical reflectance index (R2 = 0.59). Therefore, the low-cost LEDIFphotodiode approach has the potential to be a meaningful indicator of photosynthetic activity at spatial scales greater than an individual leaf and over time.

Bamboos stand out among other tall plants in being able to generate positive pressure in the xylem at night, pushing water up to the leaves and causing drops to fall from leaf tips as guttation that can amount to a steady nocturnal 'bamboo rain'. The location and mechanism of nocturnal pressure generation in bamboos are unknown, as are the benefits for the plants. We conducted a study on the tall tropical bamboo species Bambusa oldhamii (giant timber bamboo) growing outdoors in southern California under full irrigation to determine where in the plant the nocturnal pressure is generated, when it rises in the evening, and when it dissipates in the morning. We hypothesized that the build-up of positive pressure would be triggered by the cessation of transpiration-driven sap flow and that resumption of sap flow in the morning would cause the pressure to dissipate. Nocturnal pressure was observed in mature stems and rhizomes, but never in roots. The pressure was episodic and associated with stem swelling and was usually, but not always, higher in rhizomes and basal stems than in stems at greater height. Time series analyses revealed that dry atmospheric conditions were followed by lower nocturnal pressure and rainfall events by higher stem pressure. Nocturnal pressure was unrelated to sap flow and even was generated for a short time in isolated stem pieces placed in water. We conclude that nocturnal pressure in bamboo is not 'root pressure' but is generated in the pseudo-woody rhizomes and stems. It is unrelated to the presence or absence of sap flow and therefore must be created outside of vessels, such as in phloem, parenchyma, or fibres. It is unlikely to be a drought adaptation and may benefit the plants by maximizing stem water storage for daytime transpiration or by transporting nutrients to the leaves. [ABSTRACT FROM AUTHOR]

The increasing global phenomenon of soil salinization has prompted heightened interest in the physiological ecology of plant salt and alkali tolerance. Halostachys caspica belonging to Amaranthaceae, an exceptionally salt-tolerant halophyte, is widely distributed in the arid and saline-alkali regions of Xinjiang, in Northwest China. Soil salinization and alkalinization frequently co-occur in nature, but very few studies focus on the interactive effects of various salt and alkali stress on plants. In this study, the impacts on the H. caspica seed germination, germination recovery and seedling growth were investigated under the salt and alkali stress. The results showed that the seed germination percentage was not significantly reduced at low salinity at pH 5.30–9.60, but decreased with elevated salt concentration and pH. Immediately after, salt was removed, ungerminated seeds under high salt concentration treatment exhibited a higher recovery germination percentage, indicating seed germination of H. caspica was inhibited under the condition of high salt-alkali stress. Stepwise regression analysis indicated that, at the same salt concentrations, alkaline salts exerted a more severe inhibition on seed germination, compared to neutral salts. The detrimental effects of salinity or high pH alone were less serious than their combination. Salt concentration, pH value, and their interactions had inhibitory effects on seed germination, with salinity being the decisive factor, while pH played a secondary role in salt-alkali mixed stress. [ABSTRACT FROM AUTHOR]

Cystopteris fragilis is widely distributed globally, particularly in the northern hemisphere and in temperate montane regions of the southern hemisphere. Nonetheless, there is limited published evidence of its physiological ecology. This is a report of the physiological ecology of C. fragilis growing in the crevices of a stone wall in Palisades, N. Y. during the summer of 2022 when the northeastern U. S. A. experienced an extended period of excessive heat and drought. Highest laboratory measurements of maximum rehydrated photosynthesis rate (Ac) occurred in June (1.83 µmol CO2 m–2 s–1) prior to the onset of the more severe heat and drought in July and August when the photosynthesis rates declined (1.47 and 1.58, respectively). The lowest rate was found in September (1.41) prior to onset of leaf senescence and dehiscence. Dark respiration (Rd) followed a comparable trend with the highest rate in June (0.82 µmol CO2 m–2 s–1), with lower rates in July, August, and September (0.40, 0.43, and 0.55, respectively). Additional evidence is presented on leaf fluorescence including chlorophyll concentration index (C.C.I.) as well as PS II data on quantum yield efficiency (Fv/Fm) and electron transfer per reaction center (ET0/RC) during each of the five months. This study provides the first evidence that C. fragilis can be a desiccation-tolerant, 'resurrection fern' capable of dormancy enduring extreme dehydration and resumption of normal physiological activity within 24 to 48 hours after heavy precipitation events. [ABSTRACT FROM AUTHOR]

Summary: Quantifying the abundances of fungi is key to understanding natural variation in mycorrhizal communities in relation to plant ecophysiology and environmental heterogeneity. High‐throughput metabarcoding approaches have transformed our ability to characterize and compare complex mycorrhizal communities. However, it remains unclear how well metabarcoding read counts correlate with actual read abundances in the sample, potentially limiting their use as a proxy for species abundances.Here, we use droplet digital PCR (ddPCR) to evaluate the reliability of ITS2 metabarcoding data for quantitative assessments of mycorrhizal communities in the orchid species Neottia ovata sampled at multiple sites. We performed specific ddPCR assays for eight families of orchid mycorrhizal fungi and compared the results with read counts obtained from metabarcoding.Our results demonstrate a significant correlation between DNA copy numbers measured by ddPCR assays and metabarcoding read counts of major mycorrhizal partners of N. ovata, highlighting the usefulness of metabarcoding for quantifying the abundance of orchid mycorrhizal fungi. Yet, the levels of correlation between the two methods and the numbers of false zero values varied across fungal families, which warrants cautious evaluation of the reliability of low‐abundance families.This study underscores the potential of metabarcoding data for more quantitative analyses of mycorrhizal communities and presents practical workflows for metabarcoding and ddPCR to achieve a more comprehensive understanding of orchid mycorrhizal communities. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue on forage plant ecophysiology under different stress conditions. The aim of the special issue is to enhance understanding of novel mechanisms of tolerance to stresses in forage species. The issue includes six scientific articles authored by individuals from various countries, covering different stresses specific to pastoral systems worldwide. The articles highlight the significance of studying genetic variability and plant traits in developing stress-tolerant varieties for forage production. The document also emphasizes the need to evaluate post-stress recovery and the importance of increasing stress tolerance in forage species to sustain livestock systems in changing climates. [Extracted from the article]

Trichomes are common in plants from dry environments, and despite their recognized role in protection and defense, little is known about their role as absorptive structures and in other aspects of leaf ecophysiology. We combine anatomical and ecophysiological data to evaluate how trichomes affect leaf gas exchange and water balance during drought. We studied two congeneric species with pubescent leaves which co‐occur in Brazilian Caatinga: Croton blanchetianus (dense trichomes) and Croton adenocalyx (sparse trichomes). We found a novel foliar water uptake (FWU) pathway in C. blanchetianus composed of stellate trichomes and underlying epidermal cells and sclereids that interconnect the trichomes from both leaf surfaces. The water absorbed by these trichomes is redistributed laterally by pectin protuberances on mesophyll cell walls. This mechanism enables C. blanchetianus leaves to absorb water more efficiently than C. adenocalyx. Consequently, the exposure of C. blanchetianus to dew during drought improved its leaf gas exchange and water status more than C. adenocalyx. C. blanchetianus trichomes also increase their leaf capacity to reflect light and maintain lower temperatures during drought. Our results emphasize the multiple roles that trichomes might have on plant functioning and the importance of FWU for the ecophysiology of Caatinga plants during drought. Summary statement: We describe a novel pathway of foliar water absorption that involves stellate trichomes, sclereids and pectin protuberances that redistribute water inside the leaf. The absorption of dew water through this pathway benefits the ecophysiological performance of Caatinga plants during drought. [ABSTRACT FROM AUTHOR]

Tracing and quantifying water fluxes in the hydrological cycle is crucial for understanding the current state of ecohydrological systems and their vulnerability to environmental change. Especially the interface between ecosystems and the atmosphere that is strongly mediated by plants is important to meaningfully describe ecohydrological system functioning. Many of the dynamic interactions generated by water fluxes between soil, plant and the atmosphere are not well understood, which is partly due to a lack of interdisciplinary research. This opinion paper reflects the outcome of a discussion among hydrologists, plant ecophysiologists and soil scientists on open questions and new opportunities for collaborative research on the topic "water fluxes in the soil-plant-atmosphere continuum" especially focusing on environmental and artificial tracers. We emphasize the need for a multi-scale experimental approach, where a hypothesis is tested at multiple spatial scales and under diverse environmental conditions to better describe the small-scale processes (i.e., causes) that lead to large-scale patterns of ecosystem functioning (i.e., consequences). Novel in-situ, high-frequency measurement techniques offer the opportunity to sample data at a high spatial and temporal resolution needed to understand the underlying processes. We advocate for a combination of long-term natural abundance measurements and event-based approaches. Multiple environmental and artificial tracers, such as stable isotopes, and a suite of experimental and analytical approaches should be combined to complement information gained by different methods. Virtual experiments using process-based models should be used to inform sampling campaigns and field experiments, e.g., to improve experimental designs and to simulate experimental outcomes. On the other hand, experimental data are a pre-requisite to improve our currently incomplete models. Interdisciplinary collaboration will help to overcome research gaps that overlap across different earth system science fields and help to generate a more holistic view of water fluxes between soil, plant and atmosphere in diverse ecosystems.

This document is an editorial summarizing the highlights from the 12th plant growth-promoting rhizobacteria workshop. The workshop focused on the research and applications of plant growth-promoting rhizobacteria (PGPR), which are naturally occurring bacteria that benefit plants by promoting growth and controlling pests. The editorial discusses various topics covered in the workshop, including the use of PGPR to combat abiotic stresses, protect plants against pathogens, improve plant metabolite and mineral contents, and unveil the genetic architecture of PGPR-triggered growth promotion. The authors emphasize the potential of PGPR in sustainable crop production and call for collaboration between industry and academia to further advance this field. [Extracted from the article]

This article discusses the importance of stomata, which are pores on the surfaces of plants that allow for the exchange of CO2 and water vapor. Stomata play a crucial role in photosynthesis and are connected to global carbon and water cycles. The article explores various aspects of stomatal function, including their development, evolution, and the molecular mechanics behind their opening and closing. It also examines the implications of stomatal research for climate change, water availability, and crop production. The article concludes by highlighting the interdisciplinary nature of stomatal research and its significance in understanding plant physiology in the global environment. [Extracted from the article]

A recent study published in the New Phytologist journal explores the coordination between hydraulic and photosynthetic traits in co-occurring woody species. The study combines a theoretical framework with a field study to demonstrate the relationship between water transport to leaves and whole-plant processes. The researchers found that hydraulic traits, such as branch water storage and hydraulic architecture, influence the cost of gaining and using water in photosynthesis. However, further research is needed to understand the role of environmental conditions and biological factors in these patterns. The study highlights the importance of integrating trait measurements with dynamic field-based measures to improve our understanding of whole-plant processes and enhance modeling in a changing climate. [Extracted from the article]

This article provides a comprehensive overview of the life and accomplishments of Dr. Kattungal Subramaniam Manilal, a highly respected botanist, taxonomist, and professor in India. It highlights his research on the plant wealth of the Malabar Coast, his teaching and administrative experience at the University of Calicut, and his numerous awards and fellowships. The article also discusses his significant contributions to the field of botany, including his research on Ayurvedic plants, biodiversity studies in Kerala, and his work on orchids and floral morphology. Dr. Manilal's leadership and establishment of the Indian Association for Angiosperm Taxonomy are also emphasized. The text concludes with a list of his publications and further reading suggestions for interested researchers. [Extracted from the article]

Among options for atmospheric CO2 removal, sequestering soil organic carbon (SOC) via improved grazing management is a rare opportunity because it is scalable across millions of globally grazed acres, low cost, and has high technical potential. Decades of scientific research on grazing and SOC has failed to form a cohesive understanding of how grazing management affects SOC stocks and their distribution between particulate (POM) and mineral‐associated organic matter (MAOM)—characterized by different formation and stabilization pathways—across different climatic contexts. As we increasingly look to grazing management for SOC sequestration on grazinglands to bolster our climate change mitigation efforts, we need a clear and collective understanding of grazing management's impact on pathways of SOC change to inform on‐the‐ground management decisions. We set out to review the effects of grazing management on SOC through a unified plant ecophysiology and soil biogeochemistry conceptual framework, where elements such as productivity, input quality, soil mineral capacity, and climate variables such as aridity co‐govern SOC accumulation and distribution into POM and MAOM. To maximize applicability to grazingland managers, we discuss how common management levers that drive overall grazing pattern, including timing, intensity, duration, and frequency can be used to optimize mechanistic pathways of SOC sequestration. We discuss important research needs and measurement challenges, and highlight how our conceptual framework can inform more robust research with greater applicability for maximizing the use of grazing management to sequester SOC. [ABSTRACT FROM AUTHOR]

This article examines the changes in leaf respiration during the night, specifically focusing on the decrease in leaf respiratory O2-uptake and CO2-efflux. The authors analyze data from various studies and find that these decreases indicate a decrease in leaf mitochondrial electron transport and ATP demand. The article emphasizes the need for further research to understand the underlying mechanisms and species-specific differences in nocturnal changes in leaf respiration. The authors also discuss the implications of changes in the respiratory quotient (RQ), suggesting that the relative composition of respiratory substrates may shift during the early hours of the dark period. They highlight the importance of studying factors that affect RQ, such as substrate composition and demand for respiratory intermediates. Overall, this information is valuable for understanding the relationship between environmental and metabolic regulation of respiration and its impact on carbon uptake. [Extracted from the article]

Many recent studies have highlighted the importance of plant growthpromoting (rhizo)bacteria (PGPR) in supporting plant's development, particularly under biotic and abiotic stress. Most focus on the plant growthpromoting traits of selected strains and the latter's effect on plant biomass, root architecture, leaf area, and specificmetabolite accumulation. Regarding energy balance, plant growth is the outcome of an input (photosynthesis) and several outputs (i.e., respiration, exudation, shedding, and herbivory), frequently neglected in classical studies on PGPR-plant interaction. Here, we discuss the primary evidence underlying the modifications triggered by PGPR and their metabolites on the plant ecophysiology. We propose to detect PGPR-induced variations in the photosynthetic activity using leaf gas exchange and recommend setting up the correct timing for monitoring plant responses according to the specific objectives of the experiment. This research identifies the challenges and tries to provide future directions to scientists working on PGPR-plant interactions to exploit the potential of microorganisms' application in improving plant value. [ABSTRACT FROM AUTHOR]

This document, published in the International Journal of Molecular Sciences, discusses the impact of biotic and abiotic stress factors on plant specialized metabolites. It highlights the importance of plants' chemical adaptations and defense mechanisms against harmful environmental conditions and predators. The document emphasizes the mutualistic bio-chemical interactions of plants with various organisms and agents in the environment. It also mentions the relevance of studying plant interactions with stress factors in various scientific fields. The document concludes by mentioning the publication of six original articles in this Special Issue, which contribute to the understanding of the effects of stress on specialized plant metabolism. [Extracted from the article]

The water‐dependent nature of arid ecosystems is closely related to the coupling between energy input through photosynthesis and the loss of water through transpiration (Tr), which can be expressed as water use efficiency (WUE). The relationship, however, between environmental factors and plant physiology in controlling evapotranspiration is not well understood in high‐altitude arid environments. Here, we review the use of carbon isotope fractionation (δ13C) to indirectly track fluctuations in WUE and the use of the portable chamber method to partition landscape actual evapotranspiration (ETa) into Tr and bare soil evaporation (Ebs) in the alluvial deposits of the Silala River, a high elevation watershed located in northern Chile. Landscape ETa was also measured with Eddy covariance (EC) systems in the basin's riparian wetland and alluvial hillslope deposits. Carbon isotope results were consistent with what is known from the literature regarding these high‐elevation ecosystems. WUE, as estimated by carbon isotope discrimination values, decreased in summer (the wet season), and increased in winter at all sites. These results were consistent with the EC measurements. Changes in WUE were much greater in the valley wetlands than along the hillslopes, most likely due to a large drop in available soil moisture along the valley bottom during the dry season. Portable chamber results obtained during summer and winter field campaigns showed that at the landscape scale, hillslope ETa was mainly dominated by bare soil evaporation; and ETa partitioning into Tr and Ebs had a seasonal change. This article is categorized under:Engineering Water > MethodsScience of Water > Hydrological Processes [ABSTRACT FROM AUTHOR]

Christa Critchley is a distinguished researcher in basic and applied photosynthesis research. Her research has centered on the structure and function of chloroplasts and the application of chlorophyll a fluorescence to understanding the way PSII works. In her research, she used two biophysical tools, Nuclear Magnetic Resonance (NMR) and Chlorophyll (Chl) a fluorescence, as well as several other biochemical and plant physiological methods. Later in her career, she pioneered research in artificial photosynthesis (AP) focusing on the process of light-mediated water splitting and oxygen evolution. Here, only a glimpse of her life and some selected research is included. [ABSTRACT FROM AUTHOR]

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Over fifty years have passed since the publication of Harold Mooney's formative paper, "The Carbon Balance of Plants" on pages 315–346 of Volume 3 (1972) of Annual Review of Ecology and Systematics. Arguably, the conceptual framework presented in that paper, and the work by Mooney and his students leading up to the paper, provided the foundational principles from which core disciplines emerged in plant economic theory, functional trait theory and, more generally, plant physiological ecology. Here, we revisit the primary impacts of those early discoveries to understand how researchers constructed major concepts in our understanding of plant adaptations, and where those concepts are likely to take us in the near future. The discipline of functional trait ecology, which is rooted in the principles of evolutionary and economic optimization, has captured the imagination of the plant physiological ecology research community, though its emphasis has shifted toward predicting species distributions and ecological roles across resource gradients. In the face of 'big-data' research pursuits that are revealing trait expression patterns at the cellular level and mass and energy exchange patterns at the planetary scale, an opportunity exists to reconnect the principles of plant carbon balance and evolutionary optimization with trait origins at the genetic and cellular scales and trait impacts at the global scale. [ABSTRACT FROM AUTHOR]

Summary: Shrub encroachment is a common ecological state transition in global drylands and has myriad adverse effects on grasslands and the services they provide. This physiognomic shift is often ascribed to changes in climate (e.g. precipitation) and disturbance regimes (e.g. grazing and fire), but this remains debated. Aeolian processes are known to impact resource distribution in drylands, but their potential role in grassland‐to‐shrubland state changes has received little attention.We quantified the effects of 'sandblasting' (abrasive damage by wind‐blown soil) on the ecophysiology of dryland grass vs shrub functional types using a portable wind tunnel to test the hypothesis that grasses would be more susceptible to sandblasting than shrubs and, thus, reinforce transitions to shrub dominance in wind‐erodible grasslands when climate‐ or disturbance‐induced reductions in ground cover occur.Grasses and shrubs responded differently to sandblasting, wherein water‐use efficiency declined substantially in grasses, but only slightly in shrubs, owing to grasses having greater increases in day/nighttime leaf conductance and transpiration.The differential ecophysiological response to sandblasting exhibited by grass and shrub functional types could consequently alter the vegetation dynamics in dryland grasslands in favour of the xerophytic shrubs. Sandblasting could thus be an overlooked driver of shrub encroachment in wind‐erodible grasslands. [ABSTRACT FROM AUTHOR]

The environment in which plants are inserted offers numerous stimuli that can influence plant ecophysiology and metabolism. Garcinia brasiliensis is a plant species of high interest for secondary metabolites extraction, however the comprehension about its behavior in response to environmental stimuli is still scarce. Thus, this study aimed to identify the influence of seasonality on the ecophysiology, biochemistry and anatomy of G. brasiliensis, aiming to contribute for the preservation and conservation of native populations and the propagation of this species. Evaluations were carried out under field conditions on six-year-old adult plants, in four replications over four months of the year (May, September, November and February). The evaluations were carried out in the middle third of the canopy, in fully expanded leaves. Gas exchange, chlorophyll "a" fluorescence, relative chlorophyll content, leaf water potential, carbohydrate, protein and amino acid content, and leaf anatomy were assessed. Gas exchange and production of carbohydrates and proteins were higher in November, when there was the highest rainfall rate. The maximum efficiency of the photochemical process in PSII was higher in February. Seasonality influences gas exchange, chlorophyll "a" fluorescence, production of primary metabolites and the nutritional status of G. brasiliensis plants. Anatomical changes are the least pronounced due to seasonal variations. Plants were more active metabolically in November, a month typical of spring in Brazilian tropical climate, which also corresponds to the growth season. [ABSTRACT FROM AUTHOR]

Sharon E. Kingsland's book, "A Lab For All Seasons," explores the history of ecology and the development of physiological plant ecology. The book is divided into three parts, investigating the origin and development of the Phytotron, the spread of the phytotron idea worldwide, and the emergence and synthesis of ecology resulting in physiological ecology. The book covers a diverse range of topics and individuals, providing valuable insights into the development of ecology in the early postwar years. It is a must-read for those interested in the history of ecological research. [Extracted from the article]

Sharon Kingsland's book, "A Lab for All Seasons: The Laboratory Revolution in Modern Botany and the Rise of Physiological Plant Ecology," explores the development and impact of the phytotron on plant physiology, agriculture, and the emergence of physiological ecology as a scientific specialty. The phytotron, a laboratory complex consisting of greenhouses and controlled environmental chambers, was created by Dutch botanist Frits Went and designed to facilitate precise and controlled experiments on whole plants. Despite its successes, the Caltech phytotron faced challenges such as chronic underfunding and conflicting institutional priorities, leading to its closure in 1969. However, similar facilities were constructed worldwide, and Kingsland examines the diverse national contexts and research interests that shaped these phytotrons. She argues that the laboratory movement revolutionized botany and contributed to the synthesis of physiology and ecology, ultimately playing a crucial role in the field of physiological ecology and addressing the challenges of global climate change. [Extracted from the article]

Many recent studies have highlighted the importance of plant growth-promoting (rhizo)bacteria (PGPR) in supporting plant’s development, particularly under biotic and abiotic stress. Most focus on the plant growth-promoting traits of selected strains and the latter’s effect on plant biomass, root architecture, leaf area, and specific metabolite accumulation. Regarding energy balance, plant growth is the outcome of an input (photosynthesis) and several outputs (i.e., respiration, exudation, shedding, and herbivory), frequently neglected in classical studies on PGPR-plant interaction. Here, we discuss the primary evidence underlying the modifications triggered by PGPR and their metabolites on the plant ecophysiology. We propose to detect PGPR-induced variations in the photosynthetic activity using leaf gas exchange and recommend setting up the correct timing for monitoring plant responses according to the specific objectives of the experiment. This research identifies the challenges and tries to provide future directions to scientists working on PGPR-plant interactions to exploit the potential of microorganisms’ application in improving plant value.

Keywords: drought tolerance; flower; hydraulics; minimum conductance; physiological costs; water relations EN drought tolerance flower hydraulics minimum conductance physiological costs water relations 2076 2082 7 08/23/23 20230915 NES 230915 Data availability All data are available and provided in the Supplementary Information. In most cases, one flower and leaf per plant was sampled, and previous measurements suggest that intraspecific variation in flower I g i SB min sb is relatively small (Roddy I et al i ., [47]). Of the 101 species for which we measured I g i SB min sb data for both leaves and flowers, only 27 species had flowers with lower I g i SB min sb than leaves. That I g i SB min sb has been shown to scale with whole-flower hydraulic conductance reiterates the role of I g i SB min sb in regulating flower water balance (Roddy I et al i ., [47]). [Extracted from the article]

Plant Physiology and Ecophysiology (PPE) is a subject taught in the biology degree. One of the skills that students must acquire is "the ability to solve PPE problems." Acquiring this competence requires a precise working methodology, a high degree of presence, and teamwork between teachers and students. Because of the C0V1D-19 pandemic and health restrictions, we had to teach the class online. This article shows the learning methodology we employed using information and communication technologies (ICTs) for the achievement of this competence. We also analyzed the results obtained in the academic performance of the students in comparison with previous years in which the classes were face-to-face. The results confirmed that the students obtained this subject-specific competence through the ICT teaching process compared to face-to-face teaching. The study also revealed that online assessment services are not secure as they do not appear to prevent cheating behavior. Therefore, we propose this learning methodology forfuture online teaching activities although improvements in the evaluation process must be addressed. [ABSTRACT FROM AUTHOR]

The traditional index evaluation method ignores the analysis of species characteristics in the beach area of coastal tourism characteristic towns, which leads to long time-consuming evaluation and low accuracy of evaluation results. Therefore, this paper proposes a quantitative evaluation method of species diversity index in the beach area of coastal tourism characteristic towns. The species in the beach area of coastal tourism characteristic town were selected as the research object. According to the principles of community ecology and plant physiological ecology, the distribution of regional vegetation was investigated in detail. The species succession process and community structure characteristics of coastal tourism characteristic towns were analyzed. The effects of environmental factors on the succession of vegetation communities and the response of dominant herbaceous plants to the stress of main environmental factors were also analyzed, meanwhile, the physiological and ecological characteristics of dominant species and their relationship with environmental factors were monitored and analyzed. In this regard, the quantitative evaluation system of species diversity index in the beach area of coastal tourism characteristic town was established via the analytic hierarchy process. Different index weights were calculated, respectively, thus completing the quantitative evaluation of species diversity index. The results show that the method has low time-consuming and high accuracy. [ABSTRACT FROM AUTHOR]

Root‐associated fungi play a critical role in plant ecophysiology, growth and subsequent responses to disturbances, so they are thought to be particularly instrumental in shaping vegetation dynamics after fire in the boreal forest. Despite increasing data on the distribution of fungal taxonomic diversity through space and time in boreal ecosystems, there are knowledge gaps with respect to linking these patterns to ecosystem function and process.Here we explore what is currently known about postfire root‐associated fungi in the boreal forest. We focus on wildfire impacts on mycorrhizal fungi and the relationships between plant–fungal interactions and forest recovery in an effort to explore whether postfire mycorrhizal dynamics underlie plant–soil feedbacks that may influence fire‐facilitated vegetation shifts.We characterize the mechanisms by which wildfire influences root‐associated fungal community assembly. We identify scenarios of postfire plant–fungal interactions that represent putative positive and negative plant–soil feedbacks that may impact successional trajectories. We highlight the need for empirical field observations and experiments to inform our ability to translate patterns of postfire root‐associated fungal diversity to ecological function and application in models.We suggest that understanding postfire interactions between root‐associated fungi and plants is critical to predict fire effects on vegetation patterns, ecosystem function, future landscape flammability and feedbacks to climate. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Premise: Annual plants often exhibit drought‐escape and avoidance strategies to cope with limited water availability. Determining the extent of variation and factors underlying the evolution of divergent strategies is necessary for determining population responses to more frequent and severe droughts. Methods: We leveraged five Mimulus guttatus populations collected across an aridity gradient within manipulative drought and quantitative genetics experiments to examine constitutive and terminal‐drought induced responses in drought resistance traits. Results: Populations varied considerably in drought‐escape‐ and drought‐avoidance‐associated traits. The most mesic population demonstrated a unique resource conservative strategy. Xeric populations exhibited extreme plasticity when exposed to terminal drought that included flowering earlier at shorter heights, increasing water‐use efficiency, and shifting C:N ratios. However, plasticity responses also differed between populations, with two populations slowing growth rates and flowering at earlier nodes and another population increasing growth rate. While nearly all traits were heritable, phenotypic correlations differed substantially between treatments and often, populations. Conclusions: Our results suggest drought resistance strategies of populations may be finely adapted to local patterns of water availability. Substantial plastic responses suggest that xeric populations can already acclimate to drought through plasticity, but populations not frequently exposed to drought may be more vulnerable. [ABSTRACT FROM AUTHOR]

Summary: Foliar anthocyanins, as well as other secondary metabolites, accumulate transiently under nutritional stress. A misconception that only nitrogen or phosphorus deficiency induces leaf purpling/reddening has led to overuse of fertilizers that burden the environment. Here, we emphasize that several other nutritional imbalances induce anthocyanin accumulation, and nutrient‐specific differences in this response have been reported for some deficiencies. A range of ecophysiological functions have been attributed to anthocyanins. We discuss the proposed functions and signalling pathways that elicit anthocyanin synthesis in nutrient‐stressed leaves. Knowledge from the fields of genetics, molecular biology, ecophysiology and plant nutrition is combined to deduce how and why anthocyanins accumulate under nutritional stress. Future research to fully understand the mechanisms and nuances of foliar anthocyanin accumulation in nutrient‐stressed crops could be utilized to allow these leaf pigments to act as bioindicators for demand‐oriented application of fertilizers. This would benefit the environment, being timely due to the increasing impact of the climate crisis on crop performance. [ABSTRACT FROM AUTHOR]

Swertia mussotii is the most authentic raw material used in Tibetan medicine in China for its various bioactivities. This natural medicine resource is at risk of being exhausted due to the double interference of climate change and anthropogenic over-collection. Little is known about habitat characteristics and the crucial environmental factors that influence the levels of active ingredients. The goal of this study is to understand the variability in the bioactive compound content of a wide range of wild S. mussotii as it adapts to changing environmental conditions. The target compound content of the whole plant material was analyzed with the environmental explanatory variables of the field sample sites using a constrained ordination method for their correlation analysis. The results show that 16.3 percent of the sampled wild S. mussotii populations with the highest bioactive content can be grouped into the elite type. The most prominent environmental variables affecting the content of major bioactive products include altitude, aspect, soil TK content, Fe content, and C/N and N/P ratios. Altitude and aspect put indirect effects that are mediated by plant height and density, N/P ratio puts a direct effect, while soil TK content, Fe content and C/N ratio have both direct and indirect effects on the bioactivity of S. mussotii. In addition to the total negative effects of altitude and C/N ratio, the remaining factors play a driving role. These findings demonstrate variation by geographical conditions across S. mussotii accessions for physiologic responses and secondary compounds in wild populations. The knowledge gained from this study can be used for environmental and plant physiology research, efficient collection of naturally active compounds, and conservation strategies for rare natural plant resources. [ABSTRACT FROM AUTHOR]

Long‐distance movements are hypothesized to positively influence population size and stability of mobile species. We tested this hypothesis with a novel modeling approach in which moving herbivores interact with the environment created by a dynamic global vegetation model using highly mobile Mongolian gazelles in the eastern Mongolian grasslands as a case study. Gazelle population dynamics were modeled from 1901 to 2018 under two scenarios, one allowing free movement and one restricting movement. Gazelles were 2.2 times more abundant when they could move freely and were extirpated in 71% of the study area when mobility was restricted. Mobility resulted in greater population increases during times of abundant forage and smaller population decreases during drought. Reduced thermoregulatory costs associated with climate change, combined with an increase in vegetation biomass, increased gazelle abundance. Since high abundances often resulted in overgrazing and, thus, extirpation when movement was restricted, mobility had an important role in maintaining higher densities. The novel modeling approach shows how accounting for not just herbivore but also plant ecophysiology can improve our understanding of the population dynamics of highly mobile herbivores, in particular when examining the effects of habitat and climate change. Since the model simulates herbivores based on general physiological mechanisms that apply across large herbivores and the vegetation model can be applied globally, it is possible to adapt the model to other large‐herbivore systems. [ABSTRACT FROM AUTHOR]

Increasing frequencies of heatwaves combined with simultaneous drought stress in Europe threaten the ecosystem water and carbon budgets of alpine grasslands. Dew as an additional water source can promote ecosystem carbon assimilation. It is known that grassland ecosystems keep high evapotranspiration as long as soil water is available. However, it is rarely being investigated whether dew can mitigate the impact of such extreme climatic events on grassland ecosystem carbon and water exchange. Here we use stable isotopes in meteoric waters and leaf sugars, eddy covariance fluxes for H2O vapor and CO2, in combination with meteorological and plant physiological measurements, to investigate the combined effect of dew and heat-drought stress on plant water status and net ecosystem production (NEP) in an alpine grassland (2000 m elevation) during the June 2019 European heatwave. Before the heatwave, enhanced NEP in the early morning hours can be attributed to leaf wetting by dew. However, dew benefits on NEP were cancelled out by the heatwave, due to the minor contribution of dew in leaf water. Heat-induced reduction in NEP was intensified by the combined effect of drought stress. The recovery of NEP after the peak of the heatwave could be linked to the refilling of plant tissues during nighttime. Among-genera differences of plant water status affected by dew and heat-drought stress can be attributed to differences in their foliar dew water uptake, and their reliance on soil moisture or the impact of the atmospheric evaporative demand. Our results indicate that dew influence on alpine grassland ecosystems varies according to the environmental stress and plant physiology. [ABSTRACT FROM AUTHOR]

Ground-level ozone (O3) is a major air pollutant that adversely affects human health and ecosystem productivity. Removal of tropospheric O3 by plant stomatal uptake can in turn cause damage to plant tissues with ramifications for ecosystem and crop health. In many atmospheric and land surface models, the functionality of stomata opening is represented by a bulk stomatal conductance, which is often semi-empirically parameterized and highly fitted to historical observations. A lack of mechanistic linkage to ecophysiological processes such as photosynthesis may render models inadequate to represent plant-mediated responses of atmospheric chemistry to long-term changes in CO2 , climate, and short-lived air pollutant concentrations. A new ecophysiology module was thus developed to mechanistically simulate land - atmosphere exchange of important gas species in GEOS-Chem, a chemical transport model widely used in atmospheric chemistry studies. The implementation not only allows for dry deposition to be coupled with plant ecophysiology but also enables plant and crop productivity and functions to respond dynamically to atmospheric chemical changes. We conduct simulations to evaluate the effects of the ecophysiology module on simulated dry deposition velocity and concentration of surface O3 against an observation-derived dataset known as SynFlux. Our estimated stomatal conductance and dry deposition velocity of O3 are close to SynFlux with root-mean-squared errors (RMSEs) below 0.3 cms-1 across different plant functional types (PFTs), despite an overall positive bias in surface O3 concentration (by up to 16 ppbv). Representing ecophysiology was found to reduce the simulated biases in deposition fluxes from the prior model but worsen the positive biases in simulated O3 concentrations. The increase in positive concentration biases is mostly attributable to the ecophysiology-based stomatal conductance being generally smaller (and closer to SynFlux values) than that estimated by the prior semi-empirical formulation, calling for further improvements in non-stomatal depositional and non-depositional processes relevant for O3 simulations. The estimated global O3 deposition flux is 864 TgO3yr-1 with GEOS-Chem, and the new module decreases this estimate by 92 TgO3yr-1. Estimated global gross primary production (GPP) without O3 damage is 119 PgCyr-1. O3 -induced reduction in GPP is 4.2 PgCyr-1 (3.5 %). An elevated CO2 scenario (580 ppm) yields higher global GPP (+ 16.8 %) and lower global O3 depositional sink (- 3.3 %). Global isoprene emission simulated with a photosynthesis-based scheme is 317.9 TgCyr-1 , which is 31.2 TgCyr-1 (- 8.9 %) less than that calculated using the MEGAN (Model of Emissions of Gases and Aerosols from Nature) emission algorithm. This new model development dynamically represents the two-way interactions between vegetation and air pollutants and thus provides a unique capability in evaluating vegetation-mediated processes and feedbacks that can shape atmospheric chemistry and air quality, as well as pollutant impacts on vegetation health, especially for any timescales shorter than the multidecadal timescale. [ABSTRACT FROM AUTHOR]

Oxygen (δ18O) and hydrogen (δ2H) isotope ratios, and their relationship to one another (d‐excess) are altered as water travels from the atmosphere to the land surface, into soils and plants and back to the atmosphere. Plants return water to the atmosphere through transpiration (evaporation through the stomata), which causes isotopic fractionation concentrating the heavier isotopes (18O and 2H) in the water that remains behind in the leaves. The degree of isotopic fractionation during transpiration is controlled largely by climate, and as a result can be predicted using process‐based models and climate data. The modelled transpirational isotopic fractionation can be applied to plant source water isotopic values to predict leaf water isotope ratios and generate maps of isotopic composition, or isoscapes. This approach of mechanistic modelling has been well demonstrated in the first generation of global leaf water isoscapes (PLoS One, 3(6), e2447, 2008). However, use of leaf water isoscapes in fields such as hydrology, ecology, and forensics requires a new generation of updated region‐specific isoscapes. Here, we generate leaf water isoscapes of δ18O, δ2H and d‐excess for Australia, the driest vegetated continent on Earth, where leaf water represents a critical water resource for ecosystems. These isoscapes represent an improvement over previous global isoscapes due to their higher resolution, region‐specific, empirically derived plant parameters, and non‐equilibrium corrections for water vapour isotopic composition. The new isoscapes for leaf water are evaluated relative to observed isotope ratios of leaf cellulose and cherry juice. The model predictions for annual average leaf water isotope ratios showed strong correlations with these plant tissues that integrate over time. Moreover, inclusion of region‐specific leaf temperature estimates and non‐equilibirum vapour corrections improved prediction accuracy. Regionally based isoscapes provide improved characterisations of average leaf water isotope ratios needed to support research in hydrology, plant ecophysiology, atmospheric science, ecology, and geographic provenancing of biological materials. [ABSTRACT FROM AUTHOR]

Drought is expected to increase in frequency and severity in many regions in the future, so it is important to improve our understanding of how drought affects plant functional traits and ecological interactions. Imposing experimental water deficits is key to gaining this understanding, but has been hindered by logistic difficulties in maintaining consistently low water availability for plants. Here, we describe a simple method for applying soil water deficits to potted plants in glasshouse experiments. We modified an existing method (the "Snow and Tingey system") in order to apply a gradual, moderate water deficit to 50 plant species of different life forms (grasses, vines, shrubs, trees). The method requires less maintenance and manual handling compared to other water deficit methods, so it can be used for extended periods of time and is relatively inexpensive to implement. With only a few modifications, it is possible to easily establish and maintain soil water deficits of differing intensity and duration, as well as to incorporate interacting stress factors. We tested this method by measuring physiological responses to an applied water deficit in a subset of 11 tree/shrub species with a wide range of drought tolerances and water-use strategies. For this subgroup of species, stomatal conductance was 2-17 times lower in droughted plants than controls, although only half of the species (5 out of 11) experienced midday leaf water potentials that exceeded their turgor loss (i.e., wilting) point. Leaf temperatures were up to 8°C higher in droughted plants than controls, indicating that droughted plants are at greater risk of thermal damage, relative to unstressed plants. The largest leaf temperature differences (between droughted and well-watered plants) were in species with high rates of water loss. Rapid osmotic adjustment was observed in leaves of five species when drought stress was combined with an experimental heatwave. These results highlight the potential value of further ecological and physiological experiments utilizing this simple water deficit method to study plant responses to drought stress.

The data set contains images of leaf venation networks obtained from tree species in Malaysian Borneo. The data set contains 726 leaves from 295 species comprising 50 families, sampled from eight forest plots in Sabah. Image extents are approximately 1 × 1 cm, or 50 megapixels. All images contain a region of interest in which all veins have been hand traced. The complete data set includes over 30 billion pixels, of which more than 600 million have been validated by hand tracing. These images are suitable for morphological characterization of these species, as well as for training of machine-learning algorithms that segment biological networks from images. Data are made available under the Open Data Commons Attribution License. You are free to copy, distribute, and use the database; to produce works from the database; and to modify, transform, and build upon the database. You must attribute any public use of the database, or works produced from the database, in the manner specified in the license. For any use or redistribution of the database, or works produced from it, you must make clear to others the license of the database and keep intact any notices on the original database.

Increasing population pressure generates a greater demand for food and consumer products, which forces the agricultural sector to optimize the production systems, as well as to use edible and energetic specie cultivars associated with abiotic stress-reducing substances. This investigation aimed to evaluate whether silicon (Si) promotes physiological adjustments, an increase in production, higher yield, and improved quality of naturally colored cotton fibers. Five doses of silicon (0, 50, 100, 150, and 200 mg L−1) were tested in a completely randomized design. The variables assessed were physiological, production, fibers yield and quality produced by BRS Safira cultivar. Data were submitted to principal component analysis, multivariate and univariate variance, and multiple linear regression. Silicon promotes physiological adjustments, increased production, and cotton fiber quality. Optimum Si dose varies depending on the variable response. Fiber quality from cotton plants treated with Si is within the expected pattern for this cultivar and the international standard D-4605 of the American Society for Testing and Materials for fiber quality measurement. Therefore, planting BRS Safira cultivar under Si foliar applications may be recommended to improve the naturally colored fiber cotton production chain in the Brazilian semiarid region.

Sugars and other non-structural carbohydrates are known to serve as currency in plants, to either fuel metabolic activities or as storage for later use. When plants are exposed long-term to cold temperatures (b) both total (NSC) and % sugar are expected to increase as soluble sugars serve as important cryoprotectants. Together this pool of labile carbon is referred to as non-structural carbohydrates (NSCs) and is composed of soluble sugars (e.g., glucose and sucrose) and more complex carbohydrates. [Extracted from the article]

Leaf area index (LAI) is an important parameter in plant ecophysiology; it can be used to quantify foliage directly and as a measure of the photosynthetic active area and, thus, the area subject to transpiration in vegetation. The aim of this paper was to review work on remote sensing methods of estimating LAI across different forest ecosystems, crops and grasslands in terms of remote sensing platforms, sensors and models. To achieve this aim, scholarly articles with the title or keywords "Leaf Area Index estimation" or "LAI estimation" were searched on Google Scholar and Web of Science with a date range between 2010 and 2020. The study's results revealed that during the last decade, the use of remote sensing to estimate and map LAI increased for crops and natural forests. However, there is still a need for more research concerning commercial forests and grasslands, as the number of studies remains low. Of the 84 studies related to forests, 60 were related to natural forests and 24 were related to commercial forests. In terms of model types, empirical models were most often used for estimating the LAI of forests, followed by physical models. [ABSTRACT FROM AUTHOR]

In global greening, biogenic volatile organic compound (BVOC) emissions and their influencing factors have been considered due to their significant roles in the biosphere and atmosphere. Many studies have reported relationships of BVOC emissions with environmental factors and plant ecophysiology. However, the direct and indirect effects of environmental factors on BVOC emissions remain unclear, and the causal relationships between plant ecophysiology and BVOC emissions are ambiguous. We measured the isoprene and monoterpene emissions from dominant greening plants using a dynamic enclosure system and quantified the interactions of environment–-plant and ecophysiology–BVOC emissions using a path analysis model. We found that isoprene emission was directly affected by photosynthetic rate, and indirectly affected by photosynthetically active radiation and air temperature (Tair). Monoterpene emissions were directly affected by atmospheric pressure, relative air humidity and specific leaf weight, and indirectly affected by Tair. [ABSTRACT FROM AUTHOR]