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Solar-induced fluorescence (SIF) is a proxy of ecosystem photosynthesis that often scales linearly with gross primary productivity (GPP) at the canopy scale. However, the mechanistic relationship between GPP and SIF is still uncertain, especially at smaller temporal and spatial scales. We deployed a ultra-hyperspectral imager over two grassland sites in California throughout a soil moisture dry down. The imager has high spatial resolution that limits mixed pixels, enabling differentiation between plants and leaves within one scene. We find that imager SIF correlates well with diurnal changes in leaf-level physiology and gross primary productivity under well-watered conditions. These relationships deteriorate throughout the dry down event. Our results demonstrate an advancement in SIF imaging with new possibilities in remotely sensing plant canopies from the leaf to the ecosystem. These data can be used to resolve outstanding questions regarding SIF's meaning and usefulness in terrestrial ecosystem monitoring.

Societal Impact Statement: Arbuscular mycorrhizal fungi (AMF) impact the relationships between plants, aphids (insects that feed on plant phloem), and their natural enemies (insects that prey on or parasitize aphids). The presence of AMF influences the growth and population of different aphid species and affects the development of aphid‐killing wasps and their attraction to plants. This research has been conducted also considering the insects' feeding strategy and their feeding specialization. This study provides novel perspectives on how these fungi shape interactions in the natural world, offering potential insights for the development of sustainable pest management strategies in agriculture. Summary: Arbuscular mycorrhizal fungi (AMF) are major root symbionts regulating plant physiology. Their presence affects the performance of aboveground insect herbivores in relation to their feeding strategy and their feeding specialization. For example, the effect of the arbuscular mycorrhizal (AM) symbiosis on chewing insects, positive for specialists and negative for generalists, has been previously demonstrated. Conversely, the impact of AMF on phloem‐suckers with relatively different levels of specialization remains unexplored.We tested the influence of the AM Funneliformis mosseae on the fitness of the specialist aphid Acyrthosiphon pisum and the generalist aphid Myzus persicae on Vicia faba plants. Further, we investigated the effects of AMF on the higher trophic level, the aphid parasitoids Aphidius ervi (specialist) and Aphidius colemani (generalist), by evaluating plant attractiveness and parasitoid fitness. To support the results of behavioral and biological bioassays we characterized the photosynthetic parameters, the volatilome and the transcriptome of tested plants.Mycorrhizal plants proved unsuitable for the generalist M. persicae but enhanced the fitness of the specialist A. pisum. The AM symbiosis had no effects on the behavioral response of A. colemani and enhanced the attraction and fitness of A. ervi.Volatilome and transcriptome profiling corroborated the results of bioassay highlighting a bottom‐up effect of the AMF across a plant–aphid–parasitoid system. [ABSTRACT FROM AUTHOR]

Summary The primary vascular system of plants (the stele) has attracted interest from paleobotanists, developmental biologists, systematists, and physiologists for nearly two centuries. Ferns, with their diverse stelar morphology, deep evolutionary history, and prominent fossil record, have been a major focus in studies of the stele. To explain the diversity of stelar morphology, past adaptive hypotheses have invoked biomechanics, hydraulics, and drought tolerance as key selection pressures in the evolution of stelar complexity; but, these hypotheses often isolate the stele from a whole‐plant developmental context, ignoring potential covariation between vascular patterning and shoot morphology. Furthermore, incongruence between expected patterns and observed data challenge adaptive hypotheses, precluding a comprehensive explanation of stelar evolution. While ontogeny has been previously recognized as a factor in stelar diversification, it has not been fully integrated into a comprehensive framework. Here we synthesize 150‐years of research on stelar morphology, incorporating developmental, physiological, and phylogenetic data to present the ontogenetic hypothesis of stelar evolution. This hypothesis posits that stelar morphology is an integrated feature of whole‐plant ontogeny, not a trait shaped by direct selection for adaptive patterns. This shift in perspective provides an updated framework for understanding the determinants of stelar morphology and focusses future efforts to ask more incisive questions about the evolution and function of primary vascular architecture. [ABSTRACT FROM AUTHOR]

Introduction: Breeding programs have developed high-yielding Coffea arabica F1-hybrids as an adaptation against adverse conditions associated with climate change. However, theresponse to drought of coffee F1 hybrids has seldom been assessed. Methods: A trial was established with five C. arabica genotypes (2 pure lines: Catimor and Marsellesa and 3 F1 hybrids: Starmaya, Centroamericano and Mundo Maya) planted under the leguminous tree species Leuceana leucocephala. Coffee growth, yield and physiological responses were assessed under a rain-fed (control: CON) and a rainfall reduction treatment (RR) for 2 years. Results: The RR treatment created a long-term rainfall deficit in a region with suboptimal temperature similar to those predicted by climate change scenarios. Moreover, the RR treatment reduced soil water content by 14% over 2 successive years of production and increased hydric stress of the three F1-hybrids (leaf water potentials averaged -0.8 MPa under RR compared with -0.4 MPa under CON). Under RR, coffee yields were reduced from 16 to 75% compared to CON. Mundo Maya F1 hybrid was the sole high-yielding genotype apable of sustaining its yield under RR conditions. Our results suggested that its significant increase in fine root density (CON = 300 and RR = 910 root.m-2) and its maintenance of photosynthetic rate (2.5 - 3.5 mmol CO2 m-2 s-1) at high evaporative demand might explain why this genotype maintained high yield under RR condition. Discussion: This work highlights a possible drought tolerance mechanism in fruit bearing adult coffee trees where the plant fine root number increases to intake more water in order to preserve turgor and sustainphotosynthesis at high ETo and therefore conserves high yield in dry conditions. [ABSTRACT FROM AUTHOR]

Background: As identified by the research, it is imperative to develop effective ways to address the pressing problem of disease and pest susceptibility in chili agriculture and secure sustainable crop yield. The research examines the impact of various growing microclimates, watering regimens, and chili cultivars on disease incidence, pest attacks, and yield loss. Results: The study, which took place over a season, used a randomized complete block design to evaluate how well Tanjung, Unpad, and Osaka cultivars performed in four different watering regimens (100, 75, 50, and 25% ETc) and different microclimates (greenhouse, rain shelter, screen house, and open field). The findings exhibited that watering regimens and microclimates greatly influenced disease and pest occurrence, but cultivars had a minimal effect on these variables. Disease and pest attack rates were highest in the open field and lowest in the screen house. A correlation was found between lower disease and pest incidence and optimal irrigation levels (75% and 100% ETc). At lower watering regimens of 25% ETc and in the open field, yield loss was the greatest. Conclusion: The results emphasize how crucial controlled environments and appropriate irrigation techniques are to reducing crop loss and increasing production. Enhancing watering regimens and implementing screen house cultivation are two strategies for improving the productivity and sustainability of chili output. [ABSTRACT FROM AUTHOR]

The article explores the relationship between flower longevity, size, and ecophysiological traits in a tropical montane ecosystem. It discusses how larger, more conspicuous flowers attract pollinators better, increasing outcrossing probability. The study found that flower longevity is positively correlated with petal mass per area and petal thickness, indicating that longer-lived flowers are more expensive to build. Additionally, the research suggests that flower biomass and water conservation traits are linked to flower longevity and size, impacting pollination success and potentially being influenced by abiotic factors. [Extracted from the article]

The stress that the space environment can induce on plant physiology is of both abiotic and biotic nature. The abiotic space environment is characterized by ionizing radiation and altered gravity, geomagnetic field (GMF), pressure, and light conditions. Biotic interactions include both pathogenic and beneficial interactions. Here, we provide an overall picture of the effects of abiotic and biotic space-related factors on plant physiology. The knowledge required for the success of future space missions will lead to a better understanding of fundamental aspects of plant physiological responses, thus providing useful tools for plant breeding and agricultural practices on Earth. A review summarizes the effects of abiotic (ionizing radiation, altered gravity, geomagnetic field, pressure, and light conditions) and both beneficial and pathogenic biotic space-related factors on plant physiology. [ABSTRACT FROM AUTHOR]

This study explored the drought resistance mechanisms of different populations of Sporobolus ioclados (Poaceae), locally known as "Sawri," "Drabhri" and "Dhrbholi" native to Africa and the Indian Subcontinent. These populations were grown in conventional nursery practices at Khawaja Fareed Government College in Rahim Yar Khan, Pakistan, and subsequently subjected to four distinct levels of drought within carefully monitored experimental settings. The experiment was conducted in a two-factorial design involving populations and drought treatments and was repeated three times. The physiological and morphological responses of S. ioclados, including plant height, number of roots, root length, flag leaf area, stomatal features, proline concentration and nitrogen content, displayed significant variability in response to the imposed drought stress. Drought resulted in increases in proline concentration and nitrogen content. The number of roots decreased, while the length and width of the stomata increased in various populations. A combination of advanced statistical techniques, such as ANOVA, PCA, HCA, and DFA, provided a comprehensive understanding of the mechanism of plant adaptation and the extent of population diversity within the species. The Yazman and Nwab Wala populations exhibited the highest rates of photosynthesis and stomatal conductance, while S. ioclados demonstrated notable drought tolerance at the T4 level of drought stress. A negative correlation was found between proline levels, nitrogen contents, and photosynthesis, suggesting that proline has a protective role in drought. The diverse adaptation strategies indicated by S. ioclados populations have revealed the potential of this species for afforestation and climate change mitigation in dry environments. [ABSTRACT FROM AUTHOR]

High night-time temperatures (HNT) pose a threat to the sustainability of crop production, including rice. HNT can affect crop productivity and quality by influencing plant physiology, morphology, and phenology. The ethylene perception inhibitor, 1-methylcyclopropene (1-MCP), can minimize HNT-induced damage to plant membranes, thereby preventing decrease in rice yield. In this study, we employed a transcriptome approach to investigate the effects of HNT, 1-MCP, and their interaction on two Texas rice varieties, Antonio and Colorado. The plants were exposed to temperatures of 25°C (ambient night-time temperature, ANT) and 30°C (HNT) using an infrared heating system from the booting stage until harvest, while 1-MCP was applied at the booting stage of rice development. Several physiological and agronomical traits were evaluated under each condition to assess plant responses. Leaf tissues were collected from the plants grown in the ANT and HNT conditions after the heat stress and 1-MCP treatments. Based on agronomic performance, Colorado was less negatively affected than Antonio under HNT, showing a slight reduction in spikelet fertility and leaf photosynthetic rate but no significant reduction in yield. The application of 1-MCP significantly mitigated the adverse effects of HNT in Antonio. However, no significant differences were observed in yield and leaf photosynthetic rate in Colorado. Furthermore, transcriptomic data revealed distinct responsive mechanisms in Antonio and Colorado in response to both HNT and 1-MCP. Several ethylene and senescence-related transcription factors (TFs) were identified only in Antonio, suggesting that 1-MCP affected the ethylene signaling pathway in Antonio but not in Colorado. These findings contribute to our understanding of the physiological differences between varieties exhibiting susceptible and tolerant responses to high night-time temperatures, as well as their response to 1-MCP and ethylene regulation under 1-MCP. [ABSTRACT FROM AUTHOR]

Summary Plant physiological responses to increasing atmospheric CO2 concentration (iCO2), including enhanced photosynthesis and reduced stomatal conductance, impact regional and global climate. Here, I describe recent advances in understanding these effects through Earth system models (ESMs). Idealized simulations of a 1% annual iCO2 show that despite fertilization, CO2 physiological forcing contributes to 10% of warming and at least 30% of future precipitation decline in Amazonia. This reduces aboveground vegetation carbon storage and triggers positive carbon–climate feedback. ESM simulations indicate that reduced transpiration and increased heat stress from iCO2 could amplify meteorological drought and wildfire risks. Understanding these climate feedbacks is essential for improving carbon accounting in natural climate solutions, such as avoiding deforestation and reforestation, as iCO2 complicates assessing their climate benefits. [ABSTRACT FROM AUTHOR]

Soilless production systems (i.e hydroponics, aeroponics, aquaponics) have become commonplace in urban settings and controlled environments. They are efficient nutrient recyclers, space savers, and water conservers. However, they lack high levels of biological richness in the root microbiome when compared to soil production systems, which may affect plant health and nutrient uptake. To address this issue and incorporate more sustainable practices, beneficial microorganisms (i.e. Trichoderma spp., Bacillus sp.) can be added in the form of biofertilizers. However, many factors affect impacts of microorganisms and their interactions with plants. In this experiment, Black Summer Pac Choi (Brassica rapa var. Chinensis) was grown for two trials in a Deep-Water system (DWS) or a Nutrient Film Technique system (NFT) with commercial biofertilizers containing Trichoderma spp., Bacillus amyloliquefaciens, a combination of both, and a control. Plant physiology, nutrient composition, and nutrient uptake efficiency (NUE) were generally negatively affected by Trichoderma spp. both growing systems, indicating that Trichoderma may not be recommended for hydroponic production. However, Bacillus amyloliquefaciens showed promise as an effective biofertilizer in the NFT systems and had a positive influence on NUE in DWS. [ABSTRACT FROM AUTHOR]

Potato–legume intercropping has been confirmed to increase productivity in modern agricultural systems. However, the physiological and ecological mechanisms of potato–soybean intercropping for promoting tuber yield formation in potato remain unclear. Field experiments were conducted in 2022 and 2023 to explore the responses of tuber yield formation, rhizosphere soil quality, root growth, and plant physiology of potato in potato–soybean intercropping. The soil at the experimental site is Cambisols. The treatments included sole cropping potato, sole cropping soybean, and potato–soybean intercropping. Our results indicated that potato –soybean intercropping decreased the water content, increased the total K content and activities of urease and catalase in rhizosphere soil, and enhanced the root mean diameter, root projected area, and root length density in the 0–5 cm and 15–20 cm soil layers of potato. Moreover, potato–soybean intercropping improved the plant photosynthetically active radiation and light transmittance rate of the middle and lower layers as well as the leaf area index, enhanced the leaf chlorophyll b content and ribulose-1,5-diphosphate carboxylase/oxygenase activity, and increased the leaf net photosynthetic rate and organ dry matter accumulation amounts of potato. The changes in the above parameters resulted in an increased tuber weight per plant (19.4%) and commercial tuber number (42.5%) and then enhanced the equivalent tuber yield of potato (38.2%) and land equivalent ratio (1.31 in 2022 and 1.33 in 2023). Overall, potato–soybean intercropping greatly increased the equivalent tuber yield by improving the rhizosphere soil quality, root growth, and plant physiology of potato and then achieved a higher land equivalent ratio. [ABSTRACT FROM AUTHOR]

Nano- and micro-sized vesicular and colloidal structures mediate cell–cell communication. They are important players in the physiology of plants, animals, and humans, and are a subject of increasing interest. We investigated the effect of three surfactants, N-cetylpyridinium chloride (CPC), sodium dodecyl sulfate (SDS), and Triton X-100 (TX100), and two anionic polyelectrolytes, sodium polystyrene sulfonate (NaPSS) and sodium polymethacrylate (NaPMA), on nanoliposomes. In addition, the effect of SDS and TX100 on selected biological membranes (erythrocytes and microalgae) was investigated. The liposomes were produced by extrusion and evaluated by microcalorimetry and light scattering, based on the total intensity of the scattered light (Itot), hydrodynamic radius (Rh), radius of gyration (Rg), shape parameter p (=Rh/Rg,0), and polydispersity index. The EPs shed from erythrocytes and microalgae Dunaliella tertiolecta and Phaeodactylum tricornutum were visualized by scanning electron microscopy (SEM) and analyzed by flow cytometry (FCM). The Rh and Itot values in POPC liposome suspensions with added CPC, SDS, and TX100 were roughly constant up to the respective critical micelle concentrations (CMCs) of the surfactants. At higher compound concentrations, Itot dropped towards zero, whereas Rh increased to values higher than in pure POPC suspensions (Rh ≈ 60–70 nm), indicating the disintegration of liposomes and formation of larger particles, i.e., various POPC–S aggregates. Nanoliposomes were stable upon the addition of NaPSS and NaPMA, as indicated by the constant Rh and Itot values. The interaction of CPC, SDS, or TX100 with liposomes was exothermic, while there were no measurable heat effects with NaPSS or NaPMA. The SDS and TX100 increased the number density of EPs several-fold in erythrocyte suspensions and up to 30-fold in the conditioned media of Dunaliella tertiolecta at the expense of the number density of cells, which decreased to less than 5% in erythrocytes and several-fold in Dunaliella tertiolecta. The SDS and TX100 did not affect the number density of the microalgae Phaeodactylum tricornutum, while the number density of EPs was lower in the conditioned media than in the control, but increased several-fold in a concentration-dependent manner. Our results indicate that amphiphilic molecules need to be organized in nanosized particles to match the local curvature of the membrane for facilitated uptake. To pursue this hypothesis, other surfactants and biological membranes should be studied in the future for more general conclusions. [ABSTRACT FROM AUTHOR]

Droughts can affect ecosystem CO2 fluxes directly or indirectly by changing plant community composition. However, it is unknown whether shifts in plant community composition buffer or amplify the response of ecosystem CO2 fluxes to droughts with different seasonal timing, as plant phenology and physiology of the different plant functional types respond differently to droughts.To identify the interaction of drought timing and plant community composition in regulating ecosystem CO2 fluxes, we conducted a three‐year manipulative experiment in which extreme droughts occurring in the early, mid and late growing seasons were separately imposed on experimental plot communities comprising graminoids, shrubs and their combination in a semi‐arid grassland of Inner Mongolia, China.Overall, mid‐season drought caused the largest negative effects regardless of plant community composition. In addition to decreasing aboveground biomass, mid‐season drought suppressed fluxes by reducing leaf photosynthetic rate, while early‐season and late‐season drought reduced fluxes mainly by shortening growing season length. All three community compositions had consistent responses to early‐season and mid‐season droughts. However, ecosystem CO2 fluxes in the combination community were less negatively affected by late‐season drought than in either shrub or graminoid communities because the growing season length was shortened less.Synthesis. Our results highlight that it is important to account for interactions of seasonal timing and plant community composition when predicting magnitude and pathways of drought effects on ecosystem carbon cycling. [ABSTRACT FROM AUTHOR]

Cereals zinc (Zn) biofortification represents an effective strategy for alleviating human Zn malnutrition. However, understanding how to enhance Zn uptake in shoots by optimizing the soil–root interface, particularly considering Zn availability, microbiome interactions, and plant physiology, remains poorly understood, especially in high-pH soils. In this study, we investigated Zn rhizomobilization, plant Zn uptake, and the composition of bacterial and fungal communities in the rhizosphere and roots of ten high-yielding wheat cultivars with consistently contrasting grain Zn concentrations, within calcareous fields. We found that a range of beneficial bacteria, fungi/mycorrhizas, and their interactions play crucial roles in Zn rhizomobilization and wheat Zn uptake. Zn-solubilizing rhizobacteria demonstrated the ability to enhance Zn rhizomobilization, leading to a 35.4% increase in available Zn concentration and a 0.11 units reduction of soil pH. Increased colonization by arbuscular mycorrhizal fungi, along with reduced the presence of fungal pathogens, significantly promoted Zn uptake, ranging from 22 to 132% per unit of root biomass. Additionally, the enriched bacteria relevant with nitrogen cycle and plant growth-promotion not only optimized soil mineral-N/available-P supply but also potentially suppressed fungal pathogens in root and rhizosphere. Optimizing the microbiome to enhance soil nutrient supply and root health emerges as a promising strategy for improving Zn-efficient wheat cultivars' ability to uptake Zn in shoots. Combining Zn-efficient cultivars with specific soil bacteria and fungi in the rhizosphere holds potential for realizing Zn biofortification in wheat. [ABSTRACT FROM AUTHOR]

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Capsicum annuum L. has worldwide distribution, but drought has limited its production. There is a lack of research to better understand how this species copes with drought stress, whether it is reversible, and the effects of mitigating agents such as salicylic acid (SA). Therefore, this study aimed to understand the mechanisms of action of SA and rehydration on the physiology of pepper plants grown under drought conditions. The factorial scheme adopted was 3 × 4, with three water regimes (irrigation, drought, and rehydration) and four SA concentrations, namely: 0 (control), 0.5, 1, and 1.5 mM. This study evaluated leaf water percentage, water potential of shoots, chlorophylls (a and b), carotenoids, stomatal conductance, chlorophyll a fluorescence, and hydrogen peroxide (H2O2) concentration at different times of day, water conditions (irrigation, drought, and rehydration), and SA applications (without the addition of a regulator (0) and with the addition of SA at concentrations equal to 0.5, 1, and 1.5 mM). In general, exogenous SA application increased stomatal conductance (gs) responses and modified the fluorescence parameters (ΦPSII, qP, ETR, NPQ, D, and E) of sweet pepper plants subjected to drought followed by rehydration. It was found that the use of SA, especially at concentrations of 1 mM in combination with rehydration, modulates gs, which is reflected in a higher electron transport rate. This, along with the production of photosynthetic pigments, suggests that H2O2 did not cause membrane damage, thereby mitigating the water deficit in pepper plants. Plants under drought conditions and rehydration with foliar SA application at concentrations of 1 mM demonstrated protection against damage resulting from water stress. Focusing on sustainable productivity, foliar SA application of 1 mM could be recommended as a technique to overcome the adverse effects of water stress on pepper plants cultivated in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Rising CO2 concentration in the atmosphere is a matter of global concern and poses apprehension about how plants will adapt to the changing environment. Various studies have proved that under high CO2 levels, plant physiology alters and affects plant functioning. However, under elevated CO2, the stomatal characters and their relation with physiological responses are still not yet clear. To find out these changes in the stomatal parameters at ambient and two elevated CO2 (550 ppm and 700 ppm) levels, four genotypes of maize (Zea mays L.) viz. DHM-117, Harsha, Varun and M-24 were grown in open-top chambers. In the study, it was observed that the stomatal density increased, stomatal size altered, stomatal conductance (gs) and transpiration rate (Tr) decreased under elevated CO2 (eCO2) while photosynthetic rate (Pn), water use efficiency (WUE), yield and biomass, of which especially the reproductive biomass increased. Under eCO2, stomatal and physiological changes were genotypic and CO2 concentration specific. Increased stomatal density at eCO2 was mainly due to increased abaxial stomatal density. The improved Pn and reduced Tr at 550 ppm improved the WUE in the plants, while this response was not observed at 700 ppm. These results elucidate that this C4 crop responded positively to up to 550 ppm of CO2 concentrations, and beyond this, the impact was minimal. [ABSTRACT FROM AUTHOR]

This article addresses one of the current issues in education: the use of resources in biological disciplines classes that are required for students to develop meta-subject competencies. The incorporation of natural objects into educational content can create a favorable environment for teaching biology classes and assist students in developing necessary knowledge about regional flora. The authors created a set of integrated plant tasks that require knowledge of ecology, plant physiology, and evolution. The main goal of tasks is to learn about regional plant species and to control what students have learned. Certain activities are specifically created for hands-on engagement with nearby natural entities to determine their taxonomic classification, morphological characteristics, and adaptations. This approach, according to the authors, ensures productivity in biology teaching. [ABSTRACT FROM AUTHOR]

Background: Gadolinium (Gd) is an increasingly found lanthanide element in soil; thus, understanding its impact on plant physiology, biochemistry, and molecular responses is crucial. Here, we aimed to provide a comprehensive understanding of Gd (150 mg kg− 1) impacts on guar (Cyamopsis tetragonoloba L.) plant yield and metabolism and whether the symbiotic relationship with arbuscular mycorrhizal fungi (AMF) can mitigate Gd toxicity of soil contamination. Results: AMF treatment improved mineral nutrient uptake and seed yield by 38–41% under Gd stress compared to non-inoculated stressed plants. Metabolic analysis unveiled the defense mechanisms adopted by AMF-treated plants, revealing carbon and nitrogen metabolism adaptations to withstand Gd contamination. This included an increase in the synthesis of primary metabolites, such as total sugar (+ 39% compared to control), soluble sugars (+ 29%), starch (+ 30%), and some main amino acids like proline (+ 57%) and phenylalanine (+ 87%) in the seeds of AMF-treated plants grown under Gd contamination. Furthermore, fatty acid and organic acid profile changes were accompanied by the production of secondary metabolites, including tocopherols, polyamines, phenolic acids, flavones, and anthocyanins. Conclusions: Overall, the coordinated synthesis of these compounds underscores the intricate regulatory mechanisms underlying plant-AMF interactions and highlights the potential of AMF to modulate plant secondary metabolism for enhanced Gd stress tolerance. [ABSTRACT FROM AUTHOR]

In agriculture, one of the most crucial elements for sustained plant production is light. Artificial lighting can meet the specific light requirements of various plants. However, it is a challenge to find optimal lighting schemes that can facilitate a balance of plant growth and nutritional qualities. In this study, we experimented with the light intensity required for plant growth and nutrient elements. We designed three light intensity treatments, 180 μmol m−2 s−1 (L1), 210 μmol m−2 s−1 (L2), and 240 μmol m−2 s−1 (L3), to investigate the effect of light intensity on lettuce growth and quality. It can be clearly seen from the radar charts that L2 significantly affected the plant height, fresh weight, dry weight, and leaf area. L3 mainly affected the canopy diameter and root shoot ratio. The effect of L1 on lettuce phenotype was not significant compared with that of the others. The total soluble sugar, vitamin C, nitrate, and free amino acid in lettuce showed more significant increases under the L2 treatment than under the other treatments. In addition, the transpiration rate and stomatal conductance were opposite to each other. The comprehensive evaluation of the membership function value method and heatmap analysis showed that lettuce had the highest membership function value in L2 light intensity conditions, indicating that the lettuce grown under this light intensity could obtain higher yield and better quality. This study provides a new insight into finding the best environmental factors to balance plant nutrition and growth. [ABSTRACT FROM AUTHOR]

Phosphorus (P) and potassium (K) affect seedling growth, root configuration, and nutrient uptake in hydroponic rice, but there are few studies on all growth stages of rice. The purpose of this experiment was to determine the response characteristics of root morphology, plant physiology, and P and K uptake and utilization efficiency to different supplies of P and K. Two local conventional rice varieties (Shennong 265 and Liaojing 294) were used as experimental materials across four treatments, including HPHK (sufficient P and K supply), HPLK (sufficient P supply under low K levels), LPHK (sufficient K supply under low P levels) and LPLK (low P and K levels) in a hydroponic setting. The results showed that HPHK and HPLK significantly decreased the acid phosphatase activity of leaves and roots from full heading to filling stages when compared to LPHK and LPLK. Sufficient supply of P or K significantly increased the accumulation of P and K (aboveground, leaves, stem sheath, and whole plant) and root morphological parameters (root length, root surface area, total root volume, and tips) during major growth stages when compared to LP or LK levels. HPHK was significantly higher than other treatments in terms of dry weight and the root activity at the main growth stage, P and K uptake rates in nutrient solutions at various stages, related P and K efficiency at the maturity stage, yield, effective panicle number, and grain number per panicle. In addition, the effect of HPHK on the above indexes were significantly greater than those of single sufficient supply of P or K. In conclusion, HPHK can improve plant configuration, increase plant P and K absorption and root activity, and increase rice yield and related P and K utilization efficiency. [ABSTRACT FROM AUTHOR]

Studies are being conducted to develop strategies to reduce the adverse effects of salinity stress. In the present study, it was aimed to determine the interactive effects of salinity stress with biochar on plant growth-the physiological and biochemical attributes of forage peas (Pisum sativum ssp. arvense L.). Salt applications were carried out with irrigation water at concentrations of 0, 25, 50, 75, and 100 mM NaCl. The experiment was conducted using a randomized complete block design with three applications [control: 0 (B0), 2.5% biochar (B1), and 5% biochar (B2)], five salt doses [0 (S0), 25 (S1), 50 (S2), 75 (S3), and 100 (S4) mM NaCl], and three replications, arranged in a 3 × 5 factorial arrangement. In the salt-stressed environment, the highest plant height (18.75 cm) and stem diameter (1.71 mm) in forage pea seedlings were obtained with the application of B1. The root fresh (0.59 g/plant) and dry weight (0.36 g/plant) were determined to be the highest in the B1 application, both in non-saline and saline environments. A decrease in plant chlorophyll content in forage pea plants was observed parallel to the increasing salt levels. Specifically, lower H2O2, MDA, and proline content were determined at all salt levels with biochar applications, while in the B0 application these values were recorded at the highest levels. Furthermore, in the study, it was observed that the CAT, POD, and SOD enzyme activities were at their lowest levels at all salt levels with the biochar application, while in the B0 application, these values were determined to be at the highest levels. There was a significant decrease in plant mineral content, excluding Cl and Na, parallel to the increasing salt levels. The findings of the study indicate that biochar amendment can enhance forage peas' growth by modulating the plant physiology and biochemistry under salt stress. Considering the plant growth parameters, no significant difference was detected between 2.5% and 5% biochar application. Therefore, application of 2.5 biochar may be recommended. [ABSTRACT FROM AUTHOR]

Premise: Poikilohydric plants respond to hydration by undergoing dry–wet–dry cycles. Carbon balance represents the net gain or loss of carbon from each cycle. Here we present the first standard protocol for measuring carbon balance, including a custom‐modified chamber system for infrared gas analysis, 12‐h continuous monitoring, resolution of plant–substrate relationships, and in‐chamber specimen hydration. Methods and Results: We applied the carbon balance technique to capture responses to water stress in populations of the moss Syntrichia caninervis, comparing 19 associated physiological variables. Carbon balance was negative in desiccation‐acclimated (field‐collected) mosses, which exhibited large respiratory losses. Contrastingly, carbon balance was positive in hydration‐acclimated (lab‐cultivated) mosses, which began exhibiting net carbon uptake <15 min following hydration. Conclusions: Carbon balance is a functional trait indicative of physiological performance, hydration stress, and survival in poikilohydric plants, and the carbon balance method can be applied broadly across taxa to test hypotheses related to environmental stress and global change. [ABSTRACT FROM AUTHOR]

In this study, the effects of repeated cycles of drying and rehydration on some physiological traits were assessed in long shelf-life tomatoes cultivated in a typical semi-arid area of Southern Italy. Three Sicilian landraces ('Custonaci', 'Salina', and 'Vulcano') from the germplasm collection at CNR-IBE (Catania, Italy) and a commercial tomato mini-plum ('Faino Hy., control) were investigated under three water regimes: DRY (no irrigation), IRR (long-season full irrigation) and REW (post-drought rewaterings). Net photosynthetic assimilation rate (Pn), leaf transpiration (E), stomatal conductance (gs), instantaneous water use efficiency (WUEi), leaf intercellular CO2 (Ci, ppm), and leaf temperature (°C), were measured during the growing season. At harvest (late July), fruit production per plant was measured and ripened fruits were analysed for total solids (TS), soluble solids (SS), reducing sugars (RS), vitamin C (AscA), and total phenols (TP). Pn promptly responded to rewatering (REW), quickly increasing immediately after irrigation, and declined with soil drying up. All genotypes had similar physiological pathways in DRY, but in IRR, 'Faino' had higher Pn (up to 31 μmol CO2 m−2s−1) and E (up to 18 mmol H2O m−2s−1). Stomatal conductance (gs) after rewatering steeply increased and quickly declined after that. All local landraces had the same gs in IRR and REW. Variations in RWC were less pronounced than those in other physiological parameters. WUEi in REW and DRY proceeded similarly (up to 3 μmol CO2 mmol H2O). Irrigation in REW significantly promoted plant productivity over the DRY control (up to +150% in 'Vulcano'). TS and SS in REW were lower than those in DRY, but higher (+19 and +7%, respectively) than in IRR. Vitamin C was greater in DRY and REW (26 and 18% higher than in IRR, respectively). TP in all local tomatoes were significantly higher (up to +29% in 'Vulcano') than those in the commercial control. Water regime had a minor effect on TP in 'Custonaci' and 'Salina'. Principal Component Analysis (PCA) provided information on the changes in physiological and fruit quality traits in tomatoes in relation to cultivars and water regimes. The results of this study also revealed that a water-saving irrigation strategy where few irrigations are applied after prolonged periods of drought might be profitable in terms of fruit production enhancement in long shelf-life tomatoes and that limited rewaterings in most cases, help retaining high levels of fruit quality traits. [ABSTRACT FROM AUTHOR]

Root system architecture is pivotal for the acquisition of water and nutrients in maize, serving as an essential foundation for achieving high and stable yields. Identification of the genetic components and natural variations determining root traits may facilitate molecular breeding of maize varieties with better root traits. Melatonin plays an important role in plant physiology and development. In this study, nine melatonin biosynthesis genes were re-sequenced in 348 inbred lines, 68 landraces, and 32 teosintes to investigate variations related to maize root traits. The analysis of nucleotide diversity suggested that these genes may have undergone selection, particularly within their promoter regions. Marker–trait association analysis identified 26 variants significantly associated with six root traits. Five variations within the ZmTDC4 promoter were significantly correlated with both total root length (TRL) and lateral root length (LRL). Among these, SNP-1784 explained the most phenotypic variation of root traits, including TRL and LRL, that has undergone selection throughout maize domestication and improvement. Furthermore, knockout of ZmTDC4 in maize resulted in a pronounced reduction in root length, underscoring its critical role in root development. Collectively, these findings elucidate the role of melatonin synthesis genes in root development and identified favorable alleles, thus providing key loci for breeding maize varieties with superior root systems. [ABSTRACT FROM AUTHOR]

Evaluating different concentrations of oxygen on lettuce physiology, growth, and biochemical assays is pivotal for optimizing the nutrient film technique (NFT), boosting yields, and enhancing resource efficiency in sustainable greenhouse cultivation. Two lettuce varieties Lactuca sativa var. Lolo Bionta (Lugano) and Lolo Rosa (Carmesi), were grown using NFT in a greenhouse for two consecutive years during the months of December and January. A comparative methodology was adopted under a randomized complete block design (RCBD) to study plant growth under three different oxygen concentration levels: natural oxygen concentrations (NOC); elevated oxygen concentrations (EOC); and elevated oxygen concentrations under LED light (380–840 nm) (LED + EOC). The plants were exposed to EOC levels of 8.1–8.7 mg L−1 in December and 8.7–9.0 mg L−1 in January. Under LED + EOC conditions, the levels were 8.2–8.3 mg L−1 in December and 8.8–9.0 mg L−1 in January. The NOC levels were 6.8–7.1 mg L−1 in December and 7.2–7.8 mg L−1 in January for Lugano and Carmesi, respectively. The applied light intensity, measured as photosynthetic photon flux density (PPFD), ranged from 463 to 495 µmol m−2 s−1 for the Lugano and from 465 to 490 µmol m−2 s−1 for the Carmesi. The dissolved oxygen concentration and LED light exposure under greenhouse conditions had significant effects (p < 0.05) on the plant growth parameters. The biochemical and physiological attributes, including transpiration rate, stomatal conductance, nitrate, chlorophyll, sugar contents, net photosynthesis, and respiration rates, varied significantly across different oxygen concentrations. Data were analyzed using a two-way ANOVA with post hoc Tukey's HSD tests for significance (p < 0.05) using IBM SPSS Statistics (version 29.0.2.0). Both EOC and LED + EOC treatments significantly improved growth attributes compared to NOC in Lugano, with increases in plant height (16.04%, 0.85%), fresh mass (110.91%, 29.55%), root length (27.35%, 29.55%), and root mass (77.69%, 34.77%). For Carmesi, similar trends were observed with increases in plant height (5.64%, 13.27%), fresh mass (10.45%, 21.57%), root length (37.14%, 47.33%), and root mass (20.70%, 41.72%) under EOC and LED + EOC. In the intertreatment analysis, the effect of LED + EOC was more pronounced compared to EOC. In view of the intertreatment response, Lolo Bionta (Lugano) appeared to have a high overall horticultural performance (growth and yield in both EOC and LED + EOC compared to Lolo Rosa (Carmesi). The practical significance of these results lies in their potential to inform strategies for optimizing greenhouse environments, particularly through the manipulation of oxygen levels and light exposure. The significant increases in growth metrics, especially under the LED + EOC conditions, suggest that targeted environmental adjustments can lead to substantial improvements in lettuce yield and quality. The findings also contribute to the advancement of sustainable agricultural technologies aiming to enhance food security and sustainability. [ABSTRACT FROM AUTHOR]

This paper discusses the mechanisms by which fungi manipulate plant physiology and suppress plant defense responses by producing effectors that can target various host proteins. Effector-triggered immunity and effector-triggered susceptibility are pivotal elements in the complex molecular dialogue underlying plant–pathogen interactions. Pathogen-produced effector molecules possess the ability to mimic pathogen-associated molecular patterns or hinder the binding of pattern recognition receptors. Effectors can directly target nucleotide-binding domain, leucine-rich repeat receptors, or manipulate downstream signaling components to suppress plant defense. Interactions between these effectors and receptor-like kinases in host plants are critical in this process. Biotrophic fungi adeptly exploit the signaling networks of key plant hormones, including salicylic acid, jasmonic acid, abscisic acid, and ethylene, to establish a compatible interaction with their plant hosts. Overall, the paper highlights the importance of understanding the complex interplay between plant defense mechanisms and fungal effectors to develop effective strategies for plant disease management. [ABSTRACT FROM AUTHOR]

Simple Summary: Understanding how plants respond to increasing atmospheric CO2 is crucial for predicting future climate interactions. However, the long-term effects of rising CO2 on plant physiology, especially in tropical regions, are not well known. To investigate this, we studied how a CO2 increase of about 95 ppm from 1927 to 2015 affected five tropical tree species in Fiji. We analysed historical leaf samples to measure the following two key traits: how efficiently the trees use water (intrinsic water-use efficiency) and the maximum rate of conductance through leaf pores (maximum stomatal conductance). Our results showed that the responses to rising CO2 varied significantly by species. Generally, the number of stomata on the leaves was more important than their size in determining the trees' response to higher CO2 levels. While photosynthesis is a major factor in improving the water-use efficiency, changes in stomatal conductance primarily drive this trend across different species. Trees that showed greater increases in the water-use efficiency also displayed a greater reduction in stomatal conductance. Overall, our study shows the importance of considering differences in the maximum stomatal conductance when predicting how different tree species will react to increasing CO2 levels. Understanding plant physiological response to a rising atmospheric CO2 concentration (ca) is key in predicting Earth system plant–climate feedbacks; however, the effects of long-term rising ca on plant gas-exchange characteristics in the tropics are largely unknown. Studying this long-term trend using herbarium records is challenging due to specimen trait variation. We assessed the impact of a ca rise of ~95 ppm (1927–2015) on the intrinsic water-use efficiency (iWUE) and maximum stomatal conductance (gsmax) of five tropical tree species in Fiji using the isotopic composition and stomatal traits of herbarium leaves. Empirical results were compared with simulated values using models that uniquely incorporated the variation in the empirical gsmax responses and species-specific parameterisation. The magnitude of the empirical iWUE and gsmax response was species-specific, ranging from strong to negligible. Stomatal density was more influential than the pore size in determining the gsmax response to ca. While our simulation results indicated that photosynthesis is the main factor contributing to the iWUE gain, stomata were driving the iWUE trend across the tree species. Generally, a stronger increase in the iWUE was accompanied by a stronger decline in stomatal response. This study demonstrates that the incorporation of variation in the gsmax in simulations is necessary for assessing an individual species' iWUE response to changing ca. [ABSTRACT FROM AUTHOR]

Simple Summary: The use of benefic fungal species acting as plant growth promoters and defense inducers has been increasing in the last decades. Trichoderma fungi are among the most appreciated benefic fungi in agriculture. They colonize plant roots and activate systemic plant defenses against pests. Trichoderma may influence the physiology of the colonized plants; as a consequence, the behavior and the development of insects feeding on them may be affected. The main purpose of this present study was to investigate the effects of the inoculation of Trichoderma afroharzianum T22, a commercial fungal strain, on the population growth and behavior of the aphid Aphis gossypii and on the parasitism of its natural enemy Aphidius colemani, using zucchini as the model plant species. Our results show that the inoculation of T. afroharzianum T22 influences the behavior and the population growth of the aphid and its endoparasitoid. These results are discussed with regards to strategies for sustainable pest management. Fungi belonging to the genus Trichoderma have received high consideration in agriculture due to their beneficial effects on crops from their plant promotion effects and protection from disease. A role of Trichoderma fungi in triggering plant defense mechanisms against insect pests, either directly or by natural enemy attraction, has been proposed, even if the results in different studies are controversial. In this present study, using zucchini plants as a model species, we investigated the effects of Trichoderma afroharzianum strain T22 plant inoculation on the cotton aphid Aphis gossypii and its endoparasitoid Aphidius colemani. Our results showed that the inoculation with T. afroharzianum T22 promotes A. gossypii population growth and makes zucchini more attractive to the aphid. The higher abundance of aphids on Trichoderma-inoculated zucchini was compensated for by a higher presence of the mummies of Aphidius colemani. In this present study, we recorded a higher zucchini biomass, thereby confirming that Trichoderma can act as a plant growth inducer. [ABSTRACT FROM AUTHOR]

Interspecific F1 hybrids between Asian (Oryza sativa) and African rice (Oryza glaberrima) exhibit severe sterility caused by the accumulation of hybrid sterility genes/loci at 15 or more loci. The mechanisms underlying the hybrid sterility genes are largely unknown; however, a few genes associated with the killer–protector system, which is the system most frequently associated with hybrid sterility genes, have been identified. We previously produced fertile plants as tetraploids derived from diploid interspecific F1 hybrids through anther culture; therefore, it was suggested that hybrid sterility could be overcome following tetraploidization. We investigated whether tetraploid interspecific plants produced by crossing are fertile and tested the involvement of hybrid sterility genes in the process. Fertile tetraploid interspecific F1 hybrid plants were obtained by crossing 2 tetraploids of O. sativa and O. glaberrima. To elucidate the relationships between pollen fertility and the hybrid sterility loci in the tetraploid F1 microspores, we performed genetic analyses of the tetraploid F2 hybrids and diploid plants obtained from the microspores of tetraploid interspecific hybrids by anther culture. The result suggested that the tetraploid interspecific hybrids overcame pollen and seed infertility based on the proportion of loci with the killer–protector system present in the tetraploids. The heterozygous hybrid sterility loci with the killer–protector system in the tetraploid segregate the homozygous killed allele (16.7–21.4%), with more than three-quarters of the gametes surviving. We theoretically and experimentally demonstrated that fertile rice progenies can be grown from tetraploid interspecific hybrids. [ABSTRACT FROM AUTHOR]

Summary: In plants, growth and defence are controlled by many molecular pathways that are antagonistic to one another. This results in a 'growth‐defence trade‐off', where plants temporarily reduce growth in response to pests or diseases. Due to this antagonism, genetic variants that improve resistance often reduce growth and vice versa. Therefore, in natural populations, the most disease resistant individuals are often the slowest growing. In crops, slow growth may translate into a yield penalty, but resistance is essential for protecting yield in the presence of disease. Therefore, plant breeders must balance these traits to ensure optimal yield potential and yield stability. In crops, both qualitative and quantitative disease resistance are often linked with genetic variants that cause yield penalties, but this is not always the case. Furthermore, both crop yield and disease resistance are complex traits influenced by many aspects of the plant's physiology, morphology and environment, and the relationship between the molecular growth‐defence trade‐off and disease resistance‐yield antagonism is not well‐understood. In this article, we highlight research from the last 2 years on the molecular mechanistic basis of the antagonism between defence and growth. We then discuss the interaction between disease resistance and crop yield from a breeding perspective, outlining the complexity and nuances of this relationship and where research can aid practical methods for simultaneous improvement of yield potential and disease resistance. [ABSTRACT FROM AUTHOR]

Previous studies have shown that light quality and quantity affect methane emissions from plants. However, the role of photoperiod in plant-derived methane has not been addressed. We studied the effects of two photoperiods—long-day (16 h light/8 h dark), and short-day (8 h light/16 h dark)—on growth and methane emissions of lettuce (a long-day plant), mung bean (a short-day plant), and tomato (a day-neutral plant) under a temperature regime of 22/18 °C. All species were grown under both light durations. First, seeds were germinated in Petri dishes for one week, then plants were transferred to pots and randomly assigned to one of the two experimental conditions. Under each condition, twelve plants were grown for 21 days; at that time, plant growth and physiological traits, including plant dry mass, growth index, photosynthesis, chlorophyll fluorescence, total chlorophyll, nitrogen balance index, flavonoids, and anthocyanin, were measured. Lettuce plants under the short-day photoperiod had the highest methane emissions. Long-day plants that were exposed to short-day conditions and short-day plants that were exposed to long-day conditions were stressed; day-neutral plants were also stressed under short days (p < 0.05). All three species had decreased total dry mass under short-day conditions, most likely because of decreased photosynthesis and increased transpiration and stomatal conductance. Methane emission was positively correlated with shoot/root mass ratio, nonphotochemical quenching and anthocyanin; but was negatively correlated with stem height, dry mass, photosynthesis, water-use efficiency, total chlorophyll, and flavonoids (p < 0.05). This study revealed that, besides light intensity and quality, light duration can also affect methane emissions from plants. [ABSTRACT FROM AUTHOR]

Pulsed light is an emerging technique in plant physiology recognized for its ability to enhance germination and accumulate γ–aminobutyric acid in maize. Pulsed light involves exposing plants to brief, high-intensity bursts of light, which can enhance photosynthesis, improve growth, and increase resistance to environmental stresses. Despite its promising potential, the specific metabolic changes leading to γ–aminobutyric acid enrichment in maize induced by pulsed light are not fully understood. This study addresses this gap by quantifying key nutrients and γ–aminobutyric acid-related compounds during maize germination and investigating the underlying mechanisms using non-targeted metabolomics. Our findings indicate that pulsed light significantly promotes maize germination and accelerates the hydrolysis of proteins, sugars, and lipids. This acceleration is likely due to the activation of enzymes involved in these metabolic pathways. Additionally, pulsed light markedly increases the content of glutamic acid and the activity of glutamate decarboxylase, which are crucial for γ–aminobutyric acid synthesis. Moreover, pulsed light significantly reduces the activity of γ–aminobutyric transaminase, thereby inhibiting γ–aminobutyric acid decomposition and resulting in a substantial increase in γ–aminobutyric acid content, with a 27.20% increase observed in germinated maize following pulsed light treatment. Metabolomic analysis further revealed enrichment of metabolic pathways associated with γ–aminobutyric acid, including amino acid metabolism, carbohydrate metabolism, plant hormone signal transduction, energy metabolism, pyrimidine metabolism, and ABC transporters. In conclusion, pulsed light is a robust and efficient method for producing sprouted maize with a high γ–aminobutyric acid content. This technique provides a novel approach for developing sprouted cereal foods with enhanced nutritional profiles, leveraging the physiological benefits of γ–aminobutyric acid, which include stress alleviation and potential health benefits for humans. [ABSTRACT FROM AUTHOR]

An experimental field study was carried out in the Kharif season of 2023 at the Crop Research Farm, Department of Agronomy, SHUATS, Prayagraj (U.P.). The experimental replications were conducted using a Randomized Block Design, with three levels of Nitrogen (0, 60, 90kg N/ha) and A zolla spp. (2, 4, 6t/ha), and one Control (NPK 120:60:60 kg/ha). In all, there were a total of ten treatments, each reproduced three times. The tested field had sandy loam soil texture with a neutral soil pH of 7.6, low organic carbon content of 0.372%, nitrogen content of 278.4 kg/ha, phosphorous content of 29.5 kg/ha, and potassium level of 217.3 kg/ha. The experimental results showed that treatment T9 obtained significantly higher plant height (107.77 cm), dry weight (66.05 g), crop growth rate (57.27 g/m²/day), relative growth rate (0.0279 g/g/day), highest number of tillers per hill (22.07), panicles per m² (282), test weight (15.23 g), grain yield (3.67 t/ha), stover yield (6.7 t/ha), and harvest index (35.74%). Transplanted Black Rice of variety BPT-2841 exhibited significantly greater maximum gross return (1,80,551.40 INR/ha), net return (1,05,496.30 INR/ha), and B:C ratio (1.41) in treatment T9. The investigation concludes that Nitrogen, being easily transportable in soil and plants, is a constituent of amino acids, nucleic acids, chlorophyll, enzymes, and hormones. These factors are essential in plant physiology and are associated with increased tillering, biomass production, protein synthesis, grain filling, yield, and quality. The availability, absorption, and utilization of nitrogen have a significant impact on these processes. Therefore, in the present experiment, the nitrogen requirements are met by applying 90kg of nitrogen through urea combined with 6t/ha of A zolla spp. This approach revealed superior performance in terms of both crop yield and economic returns. [ABSTRACT FROM AUTHOR]

Climate change has rapidly increased incidences of frequent extreme abiotic stresses, such as heat, drought, salinity, and waterlogging. Each of these stressors negatively affects the cotton crop (Gossypium spp.) and results in significant yield decreases. Every stressful event causes specific changes in the metabolism and physiology of plants, which are linked to complex molecular alterations. Understanding the molecular mechanisms that regulate a plant's response to stress is essential to developing stress-resistant cotton varieties that can withstand various stress factors. Gene expressions in response to multiple stresses have been studied and mapped. These genes include ion transporters and heat shock proteins, which are vital to allowing adaptive responses. These approaches showed the ability to employ advanced genome sequencing and multi-omics techniques to identify dynamic gene expression patterns and elucidate intricate regulatory networks. Using genetic variation in combination with molecular techniques, it would be possible to generate stress-resilient cotton varieties that would enable sustainable cotton output in the face of abiotic stresses. Here, we reviewed the effects of major abiotic stressors on cotton plants, such as heat, salinity, drought, heavy metals, and waterlogging. We also examine the vast network of proteins, genes, and stress-sensitive signaling pathways that help cotton tolerate abiotic stress. [ABSTRACT FROM AUTHOR]

Abstract Background As identified by the research, it is imperative to develop effective ways to address the pressing problem of disease and pest susceptibility in chili agriculture and secure sustainable crop yield. The research examines the impact of various growing microclimates, watering regimens, and chili cultivars on disease incidence, pest attacks, and yield loss. Results The study, which took place over a season, used a randomized complete block design to evaluate how well Tanjung, Unpad, and Osaka cultivars performed in four different watering regimens (100, 75, 50, and 25% ETc) and different microclimates (greenhouse, rain shelter, screen house, and open field). The findings exhibited that watering regimens and microclimates greatly influenced disease and pest occurrence, but cultivars had a minimal effect on these variables. Disease and pest attack rates were highest in the open field and lowest in the screen house. A correlation was found between lower disease and pest incidence and optimal irrigation levels (75% and 100% ETc). At lower watering regimens of 25% ETc and in the open field, yield loss was the greatest. Conclusion The results emphasize how crucial controlled environments and appropriate irrigation techniques are to reducing crop loss and increasing production. Enhancing watering regimens and implementing screen house cultivation are two strategies for improving the productivity and sustainability of chili output.

Abstract This study explored the drought resistance mechanisms of different populations of Sporobolus ioclados (Poaceae), locally known as “Sawri,” “Drabhri” and “Dhrbholi” native to Africa and the Indian Subcontinent. These populations were grown in conventional nursery practices at Khawaja Fareed Government College in Rahim Yar Khan, Pakistan, and subsequently subjected to four distinct levels of drought within carefully monitored experimental settings. The experiment was conducted in a two-factorial design involving populations and drought treatments and was repeated three times. The physiological and morphological responses of S. ioclados, including plant height, number of roots, root length, flag leaf area, stomatal features, proline concentration and nitrogen content, displayed significant variability in response to the imposed drought stress. Drought resulted in increases in proline concentration and nitrogen content. The number of roots decreased, while the length and width of the stomata increased in various populations. A combination of advanced statistical techniques, such as ANOVA, PCA, HCA, and DFA, provided a comprehensive understanding of the mechanism of plant adaptation and the extent of population diversity within the species. The Yazman and Nwab Wala populations exhibited the highest rates of photosynthesis and stomatal conductance, while S. ioclados demonstrated notable drought tolerance at the T4 level of drought stress. A negative correlation was found between proline levels, nitrogen contents, and photosynthesis, suggesting that proline has a protective role in drought. The diverse adaptation strategies indicated by S. ioclados populations have revealed the potential of this species for afforestation and climate change mitigation in dry environments.

Salinity is considered the most critical environmental factor which negatively affects the germination and growth of plants. In this study, the potential of using Dead Sea water (DS) as a seed priming agent for the mitigation of the adverse effects of salinity on seed germination and growth performance of wheat (Triticum aestivum L.) was investigated. Germination of wheat seeds primed with different doses of DS; 0%, 5%, 10%, 15%, and 20% were evaluated under different saline conditions (0, 100, 200, and 300 mM NaCl). High salinity (300 mM NaCl) remarkably inhibited germination attributes and reduced seedling length. However, seeds primed with DS exhibited improved germination parameters and seedling growth. Among the different DS concentrations used, the 10% DS priming achieved the highest increase in final germination percentage tolerance, germination index, relative germination salt tolerance, and seedling length. The increased tolerance to salinity was associated with improved water imbibition, α-amylase activity, antioxidant capacity and osmotic homeostasis correlated with high proline and soluble sugar levels. In addition, DS priming increased the membrane stability index, and reduced malondialdehyde content and K+ leakage besides lowering Na+/K+ ratio. Overall, priming with DS could be a promising strategy for minimizing the damaging effects of salinity in wheat.

Yield quality and quantity in hydroponic greenhouses usually rely on optimum crop root health and effective nutrient mobility. This study evaluated the effects of applying arbuscular mycorrhizal fungi and biochar on different growth characteristics of commercial rose cultivars in a hydroponic cultivation system. In this experiment, Rosa hybrida cultivars were 'Angelina' and 'Dolce Vita'. Treatments included concentrations of 0, 1.5, 3 and 6 g L-1 biochar, and 0 and 7 g L-1 of arbuscular mycorrhizal fungi as organic biofertilizers for the growth of rose plants. Biofertilizer application at 3 g L-1 biochar and 7 g L-1 arbuscular mycorrhizal fungi optimally increased flowering shoot diameter, flower diameter, flowering shoot length, and leaf phosphorus content. The 'Dolce Vita' cultivar responded more favorably to higher concentrations of arbuscular mycorrhizal fungi and biochar than the 'Angelina' cultivar in the hydroponic culture medium. Stem diameter, stem length, and flower diameter in both cultivars improved in response to higher biochar concentrations. The increased flowering shoot length resulted from root colonization by arbuscular mycorrhizal fungi and an enhanced nutrient uptake, especially phosphorus. A higher nutrient supply increased cell division and shoot growth. [ABSTRACT FROM AUTHOR]

Drought is a major abiotic stress affecting plant growth and productivity worldwide. Henna (Lawsonia inermis L.) is an economically important plant species that is widely cultivated due to its natural dye properties and medicinal uses, and it is highly susceptible to drought stress, which limits its growth and development. This study was conducted with the aim of investigating the effect of foliar spraying of sodium nitroprusside (SNP) on the yield of henna ecotypes (Lawsonia inermis L.) under drought stress conditions in Shahdad-Iran. The experiment was conducted in the form of a split factorial design based on randomized complete block design (RCBD) in three replications. Three ecotypes of henna (Rudbar-e-Jonub, Shahdad, and Bam) were used as plant material. The findings showed that with the onset of drought, photosynthetic pigments, growth indices, net photosynthesis, and yield of dry matter of henna plant leaves decrease. However, when SNP spray treatment was applied, it significantly improved things like leaf area index, crop growth rate, net photosynthesis and leaf dry matter yield, especially when drought levels were at 25 and 50%. The natural water content of Shahdad genotype in henna plants showed the highest percentage increase in these measurements compared with other henna plant species. It can be concluded that SNP spray can increase the yield of henna plant under drought stress conditions.

Abstract Chromium (Cr) is a toxic metal in soil–plant system, hence causing possible health risks prominently in the areas with forgoing industrial activities. Copper nanoparticles (Cu NPs) have been reported as an excellent adsorbent for pollutants. Therefore, this study investigates how copper nanoparticles enhance onion growth while decreasing chromium uptake in onion plants. Additionally, it examines the potential health risks of consuming onion plants with elevated chromium levels. The results demonstrated that the addition of CuNPs at 15 mg kg−1 significantly improved the plant height (48%), leaf length (37%), fresh weight of root (61%), root dry weight (70%), fresh weight of bulb (52%), bulb dry weight (59%), leaves fresh weight (52%) and dry weight of leaves (59%), leaf area (72%), number of onion leaves per plant (60%), Chl. a (42%), chl. b (36%), carotenoids (40%), total chlorophyll (40%), chlorophyll contents SPAD value (56%), relative water contents (35%), membrane stability index (16%), total sugars (25%), crude protein (21%), ascorbic acid (19%) and ash contents (64%) at 10 mg kg−1 Cr. Whereas, maximum decline of Cr by 46% in roots, 68% in leaves and 92% in bulb was found with application of 15 mg kg−1 of Cu NPs in onion plants under 10 mg kg−1 Cr toxicity. The health risk assessment parameters of onion plants showed minimum values 0.0028 for average daily intake (ADI), 0.001911 for Non-cancer risk (NCR), and 0.001433 for cancer risk (CR) in plants treated with Cu NPs at 15 mg kg−1 concentration grown in soil spiked with 10 mg kg−1 chromium. It is concluded that Cu NPs at 15 mg kg−1 concentration improved growth of plants in control as well as Cr contaminated soil. Therefore, use of Cu NPs at 15 mg kg−1 concentration is recommended for improving growth of plants under normal and metal contaminated soils.

Cold stress has an immediate impact on plant structure and function. A large number of free radicals cause oxidative stress in plants. Cold stress causes altered membrane permeability, lipid peroxidation, and DNA damage. It denatures enzymes and disrupts plant metabolism. Different methods are being investigated for acclimatizing plants subjected to cold stress. Nanobiotechnology and bacterial strains are growing agricultural strategies. Nanoparticles’ (NPs) unique qualities (small size, high mobility, biocompatibility, low cost, and increased reactivity) make them ideal candidates in agriculture. NP and bacterial applications maintain plastid structure and function, enhance antioxidant activities, secondary metabolites, and hormone expression, and reduce electrolyte leakage. They increase the number and content of proteins involved in oxidation–reduction reactions, hormone pathways, stress signaling, and reactive oxygen species detoxification under cold stress conditions. Chitosan, zinc oxide, and titanium dioxide NPs can help plants with cold stress. Meanwhile, bacterial strains in the genus Bacillus and Pseudomonas have been tested for cold tolerance. These strategies also upregulate antifreeze proteins, which are essential for the storage of plant products. Nano-bio-fertilizers should be prepared for the sustainable development of plants under low temperatures.

Vladimir Aleksandrovich Koshkin was a prominent representative of the school of plant physiologists at the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). He introduced his ideas on the mechanisms of photosynthesis intensity as well as the distribution of photoperiod sensitivity and the rate of development among plant species diversity. He was the first to examine in detail and disclose the relationship between the carbon dioxide compensation point and leaf temperature in C3 and C4 plants. According to Dr. Koshkin, there was no change in the sign of the photoperiodic reaction in the generic evolution of Triticum L. and Aegilops L., while the spring forms of bread and durum wheat widespread in the equatorial zone demonstrated weak photoperiod sensitivity. In his work with the resource departments of VIR, Dr. Koshkin was interested in plant breeding problems in the context of developing earlier-ripening cereal cultivars with a certain reaction to the photoperiod. His joint research projects with a number of breeding centers in Russia on this problem proved effective. He participated in collecting missions in Latin American countries (Cuba, Mexico, Colombia, and Brazil) and was awarded a Timiryazev Gold Medal. Dr. Koshkin was the author of 163 scientific publications and had about 20 certificates of authorship and patents for inventions, crop cultivars and lines. Dr. Vladimir Koshkin was quick to perceive the essence of any problem and used adequate modern methods to set up and analyze high-precision experiments.

Abstract Background Biochar, a carbon-rich source and natural growth stimulant, is usually produced by the pyrolysis of agricultural biomass. It is widely used to enhance plant growth, enzyme activity, and crop productivity. However, there are no conclusive studies on how different levels of biochar application influence these systems. Methods and results The present study elucidated the dose-dependent effects of biochar application on the physiological performance, enzyme activity, and dry matter accumulation of tobacco plants via field experiments. In addition, transcriptome analysis was performed on 60-day-old (early growth stage) and 100-day-old (late growth stage) tobacco leaves to determine the changes in transcript levels at the molecular level under various biochar application levels (0, 600, and 1800 kg/ha). The results demonstrated that optimum biochar application enhances plant growth, regulates enzymatic activity, and promotes biomass accumulation in tobacco plants, while higher biochar doses had adverse effects. Furthermore, transcriptome analysis revealed a total of 6561 differentially expressed genes (DEGs) that were up- or down-regulated in the groupwise comparison under different treatments. KEGG pathways analysis demonstrated that carbon fixation in photosynthetic organisms (ko00710), photosynthesis (ko00195), and starch and sucrose metabolism (ko00500) pathways were significantly up-regulated under the optimal biochar dosage (600 kg/ha) and down-regulated under the higher biochar dosage (1800 kg/ha). Conclusion Collectively, these results indicate that biochar application at an optimal rate (600 kg/ha) could positively affect photosynthesis and carbon fixation, which in turn increased the synthesis and accumulation of sucrose and starch, thus promoting the growth and dry matter accumulation of tobacco plants. However, a higher biochar dosage (1800 kg/ha) disturbs the crucial source-sink balance of organic compounds and inhibits the growth of tobacco plants.

Abstract Cadmium (Cd) is a nonessential element in plants and has adverse effects on the growth and development of plants. However, the molecular mechanisms of Cd phytotoxicity, tolerance and accumulation in hyperaccumulators Solanum nigrum L. has not been well understood. Here, physiology, transcriptome, and metabolome analyses were conducted to investigate the influence on the S. nigrum under 0, 25, 50, 75 and 100 µM Cd concentrations for 7 days. Pot experiments demonstrated that compared with the control, Cd treatment significantly inhibited the biomass, promoted the Cd accumulation and translocation, and disturbed the balance of mineral nutrient metabolism in S. nigrum, particularly at 100 µM Cd level. Moreover, the photosynthetic pigments contents were severely decreased, while the content of total protein, proline, malondialdehyde (MDA), H2O2, and antioxidant enzyme activities generally increased first and then slightly declined with increasing Cd concentrations, in both leaves and roots. Furthermore, combined with the previous transcriptomic data, numerous crucial coding-genes related to mineral nutrients and Cd ion transport, and the antioxidant enzymes biosynthesis were identified, and their expression pattern was regulated under different Cd stress. Simultaneously, metabolomic analyses revealed that Cd treatment significantly changed the expression level of many metabolites related to amino acid, lipid, carbohydrate, and nucleotide metabolism. Metabolic pathway analysis also showed that S. nigrum roots activated some differentially expressed metabolites (DEMs) involved in energy metabolism, which may enhance the energy supply for detoxification. Importantly, central common metabolism pathways of DEGs and DEMs, including the “TCA cycle”, “glutathione metabolic pathway” and “glyoxylate and dicarboxylate metabolism” were screened using conjoint transcriptomics and metabolomics analysis. Our results provide some novel evidences on the physiological and molecular mechanisms of Cd tolerance in hyperaccumulator S. nigrum plants.

Maize cultivation is under the growing threat of charcoal rot (Macrophomina phaseolina). Chemical control of diseases imparts serious health hazards to humans and the ecosystem. Biochar as an alternative disease management approach has been under consideration of the researchers for some time now. The biochar utilized in this study was derived from maize stalks and cobs. Crystallographic structure, inorganic minerals content and size of maize biochar were analyzed by powder X-ray diffractometer, while scanning electron microscopy revealed rough, irregular, tubular structure of the biochar surface. EDX spectra revealed that the maize biochar composition was dominated by 'C' followed by 'O'. The current study was designed to determine the synergistic effect of maize biochar (MB), and biocontrol agent (BCA) Trichoderma viride as soil amendments on the suppression of M. phaseolina. In vitro bioassays were conducted to check the efficiency of antagonistic effect of Trichoderma spp., in combination with maize biochar. On the basis of maximum mycelial growth inhibition T. viride was selected for a glasshouse experiment. Maize plants were grown in pots containing a mixture of soil with MB at application at the rate of 3 and 6% (v/v) separately, associated with or without T. viride. Treatments amended with 3% MB inoculated with M. phaseolina significantly reduced the percentage disease severity index by 40%. While in the presence of T. viride, 3% MB showed maximum disease suppression and a minimum percentage severity index i.e. 60 and 20%, respectively. Highest nitrogen contents were 18.4 g kg−1 observed in treatment 6% MB, while highest phosphorus and potassium contents were 3.11 and 15.2 g kg−1, respectively in the treatment with 3% MB. Conclusively, the effect of variable concentrations of maize biochar and T. viride as soil amendment was evident on the development of charcoal rot, growth and physiology of maize plants. According to the available literature, our report is the first on the implementation of biochar in synergism with T. viride to suppress the charcoal rot in maize. [ABSTRACT FROM AUTHOR]

In the course of past two decade anthropogenic activities have reinforced, begetting soil and water defilement. A plethora of heavy metals alters and limits plant growth and yield, with opposing effect on agricultural productivity. Silicon often perceived as plant alimentary 'nonentity'. A suite of determinants associated with silicon have been lately discerned, concerning plant physiology, chemistry, gene regulation/expression and interaction with different organisms. Exogenous supplementation of silicon renders resistance against heavy-metal stress. Predominantly, plants having significant amount of silicon in root and shoot thus are barely prone to pest onset and manifest greater endurance against abiotic stresses including heavy-metal toxicity. Silicon-mediated stress management involves abatement of metal ions within soil, co-precipitation of metal ions, gene modulation associated with metal transport, chelation, activation of antioxidants (enzymatic and non-enzymatic), metal ion compartmentation and structural metamorphosis in plants. Silicon supplementation also stimulates expression of stress-resistant genes under heavy-metal toxicity to provide plant tolerance under stress conditions. Ergo, to boost metal tolerance within crops, immanent genetic potential for silicon assimilation should be enhanced. Current study, addresses the potential role and mechanistic interpretation of silicon induced mitigation of heavy-metal stress in plants. [ABSTRACT FROM AUTHOR]

Chromium (Cr) is a toxic metal in soil–plant system, hence causing possible health risks prominently in the areas with forgoing industrial activities. Copper nanoparticles (Cu NPs) have been reported as an excellent adsorbent for pollutants. Therefore, this study investigates how copper nanoparticles enhance onion growth while decreasing chromium uptake in onion plants. Additionally, it examines the potential health risks of consuming onion plants with elevated chromium levels. The results demonstrated that the addition of CuNPs at 15 mg kg−1 significantly improved the plant height (48%), leaf length (37%), fresh weight of root (61%), root dry weight (70%), fresh weight of bulb (52%), bulb dry weight (59%), leaves fresh weight (52%) and dry weight of leaves (59%), leaf area (72%), number of onion leaves per plant (60%), Chl. a (42%), chl. b (36%), carotenoids (40%), total chlorophyll (40%), chlorophyll contents SPAD value (56%), relative water contents (35%), membrane stability index (16%), total sugars (25%), crude protein (21%), ascorbic acid (19%) and ash contents (64%) at 10 mg kg−1 Cr. Whereas, maximum decline of Cr by 46% in roots, 68% in leaves and 92% in bulb was found with application of 15 mg kg−1 of Cu NPs in onion plants under 10 mg kg−1 Cr toxicity. The health risk assessment parameters of onion plants showed minimum values 0.0028 for average daily intake (ADI), 0.001911 for Non-cancer risk (NCR), and 0.001433 for cancer risk (CR) in plants treated with Cu NPs at 15 mg kg−1 concentration grown in soil spiked with 10 mg kg−1 chromium. It is concluded that Cu NPs at 15 mg kg−1 concentration improved growth of plants in control as well as Cr contaminated soil. Therefore, use of Cu NPs at 15 mg kg−1 concentration is recommended for improving growth of plants under normal and metal contaminated soils. [ABSTRACT FROM AUTHOR]

Plant diseases are caused by various microorganisms such as bacteria, fungi, viruses, and nematodes. These diseases impact crop growth, reduce produce quality, and lead to financial losses. Plant disease can be caused by single pathogens or by interactions called "disease complexes", involving two or more pathogens. In these cases, the disease severity caused by the pathogens combined is greater than the sum of the disease caused by each pathogen alone. disease complexes formed among plant-parasitic nematodes (PPNs) with bacteria, fungi, or viruses, can occur. PPNs either enhance the other pathogen incidence and severity or are necessary for disease symptoms to be expressed. PPNs can do so by being wounding agents, vectors, modifiers of plant biochemistry and physiology, or altering the rhizosphere microbiome. This review identifies several PPNs-plant pathogens disease complexes in crop production to discuss how understanding such interactions is key for improving management practices. [ABSTRACT FROM AUTHOR]