Search Results (686)

Tomato (Solanum lycopersicum L.) production in greenhouse systems increasingly relies on integrated fertilization and soil management strategies to enhance yield, fruit quality, and resilience to biotic stressors. This study evaluated the combined effects of five fertilization regimes and two contrasting soil tillage systems—rotary tillage (RT) and conventional plowing (P)—on the performance of greenhouse-grown ‘Bacuni’ tomatoes. Experimental assessments encompassed biometric traits, photosynthetic pigments (chlorophyll and anthocyanins), carotenoid concentrations (carotenes and lycopene), soluble solids, and total dry matter contents, as well as agronomic variables including fruit weight, fruit number, and total yield. Incidence of key pests and diseases, alongside soil compaction levels, were also quantified. Fertilization with Nutriplant 20:20:20, as well as the application of Albit both resulted in a marked stimulation of vegetative growth, while the highest yields were recorded in P × Orgevit + Kerafol (6962.65 g plant⁻¹; +44.6% vs. control) and RT × Albit + Turboroot (6208.22 g plant⁻¹; +16.2% vs. control). Rotary tillage consistently improved nutrient uptake efficiency and yield relative to plowing, highlighting the role of soil structure in modulating plant performance. Treatments with Albit and Turboroot also enhanced resistance to Tetranychus urticae and Xanthomonas campestris, indicating a dual benefit for productivity and phytosanitary status. The results underscore the importance of harmonizing fertilization strategies with soil management practices to optimize greenhouse tomato production. Integrative approaches that combine biostimulants, organic amendments, and soil structural optimization offer a viable pathway toward high-yield, high-quality, and disease-resilient crops in controlled environment agriculture. Full article

Chlorophyll biosynthesis is essential for photosynthesis and plant development. Disruptions in this pathway often manifest as pigment-deficient phenotypes. This study characterizes the morphological, anatomical, and physiological consequences of a chlorophyll-deficient rice mutant (yellow seedling, YS) caused by a loss-of-function mutation in the OsCHLI gene, which encodes the ATPase subunit of magnesium chelatase. Comparative analyses between YSs and wild-type green seedlings (GSs) revealed that YSs exhibited severe growth retardation, altered mesophyll structure, reduced xylem and bulliform cell areas, and higher stomatal and papillae density. These phenotypes were strongly light-dependent, indicating that OsCHLI plays a crucial role in light-mediated chloroplast development and growth. Transcriptome analysis further revealed global down-regulation of photosynthesis-, TCA cycle-, and cell wall-related genes, alongside selective up-regulation of redox-related pathways. These results suggest that chlorophyll deficiency induces systemic metabolic reprogramming, prioritizing stress responses over growth. This study highlights the multifaceted role of OsCHLI in plastid maturation, retrograde signaling, and developmental regulation, providing new insights for improving photosynthetic efficiency and stress resilience in rice. Full article

The use of external triggers in microalgae cultivation has emerged as a promising approach to enhance biomass production and biochemical composition. For instance, magnetic fields (MFs) have had their potential to modulate cellular metabolism and physiological responses explored. This study investigated the effects of MF exposure on Dunaliella salina and evaluated its impact on biomass production, pigment synthesis and biochemical composition. The highest biomass concentration (0.59 g L⁻¹) was observed under continuous exposure to 60 mT (MF60-24 h); it represented a 51% increase in comparison with the control. A gradual rise in pH, which reached 10.83, was observed during cultivation. MF exposure also enhanced chlorophyll-a (118%) and carotenoid (95%) concentrations; thus, it improved photosynthetic efficiency and potential oxidative stress responses. The biochemical composition revealed a shift in metabolic pathways after prolonged MF exposure (24 h d⁻¹), decreasing carbohydrate content by 7%, while increasing lipid accumulation by 7%. Scanning electron microscopy (SEM) indicated structural modifications on the cell surface induced by the MF. Therefore, MF applications improve D. salina cultivation and enhance biomass composition for biotechnological applications. Full article

Arundo donax exhibits strong comprehensive stress resistance and high levels of crude protein and crude fiber, making it an ideal perennial forage crop. It adapts to various abiotic stresses and serves as a new model for studying plant stress response mechanisms. A. donax frequently encounters diverse environmental stresses during agricultural production, including drought, waterlogging, and temperature extremes. However, the response mechanisms of A. donax to multiple stresses remains elusive. By analyzing publicly available transcriptome data, we identified 9089, 19,272, and 8585 differentially expressed genes (DEGs) and 742 DEGs shared in the leaves of A. donax under drought, waterlogging, and cold conditions. The data showed that A. donax exhibits differential activation patterns in endogenous hormone signaling (jasmonate/gibberellin), energy metabolism (UDP-glucosyltransferase), and nitrogen metabolism pathways (acyltransferase) under these stresses. DEGs involved in the nitrogen metabolism and phenylpropanoid metabolism pathways were significantly enriched, while the gene expression patterns of these pathways varied among the drought, waterlogging, and cold stress conditions. Different stresses could affect the nitrogen accumulation in A. donax leaves. In addition, pairwise DEG comparisons indicated active roles of antioxidant defense and photosynthetic system in multiple stress responses. Physiological measurements validated these transcriptional changes: the activities of antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD)) increased significantly, minimizing oxidative damage. Meanwhile, the photosynthetic pigments content also decreased in response to the three stresses. Soluble sugars, pyruvate, malate, and citrate, which are involved in energy metabolism in the leaves of A. donax, accumulated to sustain themaintenance of the plant’s own energy metabolism. In conclusion, our study revealed the transcriptome-based regulatory network related with synergistic response mechanisms of A. donax leaves under multiple stress conditions. Full article

To investigate how far-red (FR) light affects tobacco leaf growth, we established different light conditions, namely, CK: white (WL), T1: red (R), T2: red–white (R+WL) combination, T3: white–far-red (WL+FR) combination, and T4: white–red–far-red (WL+R+FR) combination; conducted supplemental light experiments on tobacco; and evaluated the growth of tobacco leaves by determining the biomass, size of the leaves, etc. In addition, the auxin (IAA) content and expression of leaf growth-related genes were examined to further reveal the mechanism of the FR regulation of tobacco leaf growth. The results show a maximum reduction in leaf area size of more than 90% and in fresh dry mass of more than 85%, while the chlorophyll content increased by more than 28%. in tobacco leaves exposed to FR compared with those exposed to white light. Meanwhile, levels of auxin IAA were increased by 113% (T3) and 17% (T4) under far-red light treatment. The anatomical structure of the tobacco leaves showed that FR reduced the number of epidermal cells in the leaves but increased the cell size. Subsequent findings revealed that FR’s impact on leaf growth was mediated through the PHYB–PIF7–IAA signaling pathway, wherein it regulated cell division and growth-related genes. This substantiates that FR diminishes the tobacco leaf area by impeding cell division rather than inhibiting cell growth. In this study, we explored the effects of far-red (FR) light on tobacco leaf growth changes and constructed a model of the related signaling pathways. Our results reveal a novel mechanism by which far-red light regulates the growth of tobacco leaves, elucidating how far-red light affects their growth and response to shading conditions. This finding not only provides a scientific basis for the optimization of high-density tobacco planting but also helps to improve photosynthetic efficiency and yield, providing strong support for the sustainable development of tobacco farming. Full article

Investigating the physiological responses and resistance mechanisms in plants under drought stress provides critical insights for optimizing irrigation water utilization efficiency and promoting the development of irrigation science. In this study, cotton seedlings were cultivated in a light incubator. Three drought stress levels were applied: mild (M1, 50–55% field moisture), moderate (M2, 45–50%), and severe (M3, 40–45%). Transcriptome analysis was performed under mild and severe stress. The results revealed that differentially expressed genes (DEGs) related to proline degradation were down-regulated and proline content increased in cotton. Under different stress treatments, cotton exhibited a stress-intensity-dependent regulation of carbohydrate metabolism and soluble sugar content decreased and then increased. And the malondialdehyde content analysis revealed a dose-dependent relationship between stress intensity and membrane lipid peroxidation. Stress activated the antioxidant system, leading to the down-regulation of DEGs for reactive oxygen species production in the mitogen-activated protein kinase (MAPK) signaling pathway. Concurrently, superoxide dismutase activity and peroxidase content increased to mitigate oxidative damage. Meanwhile, the photosynthetic performance of cotton seedlings was inhibited. Chlorophyll content, stomatal conductance, the net photosynthetic rate, the transpiration rate and water use efficiency were significantly reduced; intercellular carbon dioxide concentration and leaf stomatal limitation value increased. But photosynthesis genes (e.g., PSBO (oxygen-evolving enhancer protein 1), RBCS (ribulose bisphosphate carboxylase small chain), and FBA2 (fructose-bisphosphate aldolase 1)) in cotton were up-regulated to coordinate the photosynthetic process. Furthermore, cotton seedlings differentially regulated key biosynthesis and signaling components of phytohormonal pathways including abscisic acid, indoleacetic acid and gibberellin. This study elucidates the significant gene expression of drought-responsive transcriptional networks and relevant physiological response in cotton seedlings and offers a theoretical basis for developing water-saving irrigation strategies. Full article

Forage sorghum (Sorghum bicolor (L.)) is a cereal native to Africa and belongs to the family Poaceae. It is a forage with a C4 photosynthetic pathway that stands out for its ability to adapt to different environments; it is able to produce even in unfavorable circumstances. The objective of this study was to analyze the attenuating effect of the brassinosteroid hormone in the form of 24-epibrassinolide on forage sorghum plants subjected to water deficit and rehydration. A completely randomized design (CRD) was used in the experiment. A 2 × 3 × 5 factorial arrangement was used, with two water conditions (water deficit and rehydration), three brassinosteroid doses (0 nM, 50 nM, and 100 nM as 24-epibrassinolide), and five replicates. The experiment was conducted in a greenhouse. Sorghum seeds were sown in pots with a capacity of 3 kg of substrate. Analyses were performed on the roots and leaves of sorghum plants at different growth stages. The macronutrients (N, P, K, Ca, and Mg) were analyzed in the soil physics laboratory. As a result, the content of N, P, K, Ca, and Mg decreased under a water deficit and was then restored by the hormone 24-epibrassinolide, which was able to restore these nutrients. The effect of the hormone under rehydration had a positive effect, increasing the levels of nutrients. Given the above, it was possible to conclude that there were no significant divergences between the treatments during the period of irrigation suspension. Among the tested concentrations, 50 nM of 24-epibrassinolide showed the most consistent improvements in nutrient concentrations under water-deficit conditions, suggesting a potential role in mitigating nutritional imbalance during stress. Rehydrated plants maintained nutrient levels similar to the controls regardless of 24-epibrassinolide application. However, it is important to note that nutritional quality indices such as crude protein and total digestible nutrients (TDN) were not evaluated in this study, which limits direct conclusions about the forage nutritional value. Full article

Passiflora edulis propagation relies extensively on grafting, yet the optimization of pruning strategies for scion quality remains empirically guided. This study elucidates the physiological and molecular mechanisms underlying scion quality across five leaf retention treatments (0%, 25%, 50%, 75%, and unpruned control). The 50% partial leaf retention (50% PLR) treatment optimally promoted axillary bud development in passion fruit through coordinated physiological and molecular adaptations. This treatment significantly outperformed other treatments in terms of both bud sprouting rate and growth parameters (including length and diameter). Physiological analyses demonstrated transient auxin accumulation coupled with synchronized antioxidant system activation, maintaining redox homeostasis. Transcriptomic profiling identified upregulation of genes in the auxin signaling pathway and cytokinin activators, while dormancy-related genes were suppressed. These findings establish 50% PLR as an optimal threshold that balances photosynthetic capacity with hormonal regulation, providing a science-based strategy to standardize grafted seedling production, while enhancing scion quality for grafting efficiency. Full article

Climate change due to global warming increases the susceptibility of plants to multiple combined stresses. Soil salinization and high temperature stresses that co-occur in arid/semiarid regions severely restrict the growth and development of plants. Although alfalfa (Medicago sativa L.) is an important forage grass, the physiological mechanisms driving its responses to combined salt and heat stress are not yet clear. This study aimed to reveal the physiological and biochemical response mechanisms of six alfalfa cultivars to different stresses by comparing plant morphology, agronomic traits, photosynthetic characteristics, and physiological and biochemical responses under control conditions, salt stress (200 mM NaCl), heat stress (38 °C), and combined salt and heat stress. Compared with single stresses, combined stress significantly inhibited the growth and biomass accumulation of alfalfa. Under combined stress, the cultivars presented decreases in plant height and total fresh biomass of 11.87–26.49% and 28.22–39.97%, respectively, compared with those of the control plants. Heat stress promoted alfalfa photosynthesis by increasing stomatal conductance, net photosynthetic rate, and transpiration rate, while salt stress and combined stress significantly suppressed these effects. Combined stress significantly increased the concentration of Na⁺ but decreased that of K⁺ and the relative water content in alfalfa leaves. Compared with the control and single stress treatments, combined stress significantly increased the level of membrane lipid peroxidation and accumulation of reactive oxygen species. The proline contents in the leaves of the different alfalfa cultivars were 2.79–11.26 times greater under combined stress than in the control. Combined stress causes alfalfa to redistribute energy from growth and development to stress defense pathways, ultimately leading to a reduction in biomass. Our study provides theoretical guidance for analyzing the mechanisms of grass resistance to combined salt and heat stress. Full article

Walnut (Juglans regia L.), an ecologically and economically important species, requires the elucidation of its salt stress response mechanisms for improved salt tolerance breeding. This study elucidates the physiological and molecular mechanisms through which exogenous methyl jasmonate (MeJA) mitigates salt stress in walnut, providing novel strategies for salt-tolerant cultivar development. This integrated study combined physiological, biochemical, and multi-omics analyses to decipher how exogenous MeJA enhances ROS scavenging through the synergistic activation of phenylalanine (Phe), tryptophan (Trp), and α-linolenic acid pathways, establishing a multilevel antioxidant defense network. MeJA treatment effectively mitigated salt stress-induced oxidative damage, as demonstrated by a significant 16.83% reduction in malondialdehyde (MDA) content, concurrent 11.60%, 10.73% and 22.25% increases in superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, respectively, the elevation of osmoregulatory soluble sugars (SS), and 1.2- to 2.0-fold upregulation of key antioxidant enzyme genes (SOD, POD, APX, GPX, DHAR) and elevated osmoregulatory substances (soluble sugars, SS). Improved photosynthetic parameters (P_n, G_s) and chlorophyll fluorescence efficiency (F_v/F_m) collectively indicated reduced oxidative stress (improved by 7.97–23.71%). Joint metabolomic-transcriptomic analyses revealed MeJA-enhanced ROS scavenging via the coordinated regulation of Phe, Trp, and α-linolenic acid pathways. In summary, MeJA significantly enhanced reactive oxygen species (ROS) scavenging efficiency and comprehensive antioxidant capacity in walnut seedlings through the synergistic regulation of key metabolic pathways, effectively mitigating salt stress. These findings establish a crucial mechanistic foundation for understanding plant salt stress responses and advance the utilization of MeJA-mediated strategies for the genetic improvement of salinity tolerance in walnut. Future research should prioritize optimizing MeJA application protocols and functionally validating key regulatory genes for breeding applications. Full article

Planting patterns and irrigation amounts are key factors affecting maize yield. This study adopted a two-factor experimental design, with planting pattern as the main plot and irrigation amount as the subplot, to investigate the effects of irrigation levels under different planting patterns (including uniform row spacing and alternating wide-narrow row spacing) on spring maize yield and water use efficiency in Xinjiang. Through this approach, the study examined the mechanisms by which planting pattern and irrigation amount influence maize growth, yield formation, and water use efficiency. Experiments conducted at the Agricultural Science Research Institute of the Ninth Division of Xinjiang Production and Construction Corps demonstrated that alternating wide-narrow row spacing combined with moderate irrigation (5400 m³/hm²) significantly optimized maize root distribution, improved water use efficiency, and increased leaf area index and net photosynthetic rate, thereby promoting dry matter accumulation and yield enhancement. In contrast, uniform row spacing under high irrigation levels increased yield but resulted in lower water use efficiency. The study also found that alternating wide-narrow row spacing enhanced maize nutrient absorption from the soil, particularly phosphorus utilization efficiency, by improving canopy structure and root expansion. This pattern exhibited comprehensive advantages in resource utilization, providing a theoretical basis and technical pathway for achieving water-saving and high-yield maize production in arid regions, which holds significant importance for promoting sustainable agricultural development. Full article

Nitrogen (N) and potassium (K) are essential macronutrients for plants whose functions and interactions profoundly influence plant physiological metabolism, environmental adaptation, and agricultural production efficiency. This review summarizes research advances in plant N and K nutrition and their interaction mechanisms, elucidating the key physiological functions of N and K individually and their respective absorption and transport mechanisms involving transporters such as NRTs and HAKs/KUPs. The review discusses the types of nutrient interactions (synergism and antagonism), with a primary focus on the physiological basis of N–K interactions and their interplay in root absorption and transport (e.g., K⁺-NO₃⁻ co-transport; NH₄⁺ inhibition of K⁺ uptake), photosynthesis (jointly optimizing CO₂ conductance, mesophyll conductance, and N allocation within photosynthetic machinery to enhance photosynthetic N use efficiency, PNUE), as well as sensing, signaling, co-regulation, and metabolism. This review emphasizes that N–K balance is crucial for improving crop yield and quality, enhancing fertilizer use efficiency (NUE/KUE), and reducing environmental pollution. Consequently, developing effective N–K management strategies based on these interaction mechanisms and implementing Balanced Fertilization Techniques (BFT) to optimize N–K ratios and application strategies in agricultural production represent vital pathways for ensuring food security, addressing resource constraints, and advancing green, low-carbon agriculture, including through coordinated management of greenhouse gas emissions. Full article

Since the onset of industrialization, the safety of arable land has become a pressing global concern, with soil salinization emerging as a critical threat to agricultural productivity and food security. To address this challenge, the cultivation of economically valuable salt-tolerant plants has been proposed as a viable strategy. In the study, we investigated the physiological and molecular responses of Lycium ruthenicum Murr. to varying NaCl concentrations. Results revealed a concentration-dependent dual effect: low NaCl levels significantly promoted seed germination, while high concentrations exerted strong inhibitory effects. To elucidate the mechanisms underlying these divergent responses, a combined analysis of metabolomics and transcriptomics was applied to identify key metabolic pathways and genes. Notably, salt stress enhanced photosynthetic efficiency through coordinated modulation of ribulose 5-phosphate and erythrose-4-phosphate levels, coupled with the upregulation of critical genes encoding RPIA (Ribose 5-phosphate isomerase A) and RuBisCO (Ribulose-1,5-bisphosphate carboxylase/oxygenase). Under low salt stress, L. ruthenicum maintained intact cellular membrane structures and minimized oxidative damage, thereby supporting germination and early growth. In contrast, high salinity severely disrupted PS I (Photosynthesis system I) functionality, blocking energy flow into this pathway while simultaneously inducing membrane lipid peroxidation and triggering pronounced cellular degradation. This ultimately suppressed seed germination rates and impaired root elongation. These findings suggested a mechanistic framework for understanding L. ruthenicum adaptation under salt stress and pointed out a new way for breeding salt-tolerant crops and understanding the mechanism. Full article

Flavonoids serve as crucial plant antioxidants in drought tolerance, yet their antioxidant regulatory mechanisms within mycorrhizal plants remain unclear. In this study, using a two-factor design, trifoliate orange (Poncirus trifoliata (L.) Raf.) seedlings in the four-to-five-leaf stage were either inoculated with Funneliformis mosseae or not, and subjected to well-watered (70–75% of field maximum water-holding capacity) or drought stress (50–55% field maximum water-holding capacity) conditions for 10 weeks. Plant growth performance, photosynthetic physiology, leaf flavonoid content and their antioxidant capacity, reactive oxygen species levels, and activities and gene expression of key flavonoid biosynthesis enzymes were analyzed. Although drought stress significantly reduced root colonization and soil hyphal length, inoculation with F. mosseae consistently enhanced the biomass of leaves, stems, and roots, as well as root surface area and diameter, irrespective of soil moisture. Despite drought suppressing photosynthesis in mycorrhizal plants, F. mosseae substantially improved photosynthetic capacity (measured via gas exchange) and optimized photochemical efficiency (assessed by chlorophyll fluorescence) while reducing non-photochemical quenching (heat dissipation). Inoculation with F. mosseae elevated the total flavonoid content in leaves by 46.67% (well-watered) and 14.04% (drought), accompanied by significantly enhanced activities of key synthases such as phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), chalcone isomerase (CHI), 4-coumarate:coA ligase (4CL), and cinnamate 4-hydroxylase (C4H), with increases ranging from 16.90 to 117.42% under drought. Quantitative real-time PCR revealed that both mycorrhization and drought upregulated the expression of PtPAL1, PtCHI, and Pt4CL genes, with soil moisture critically modulating mycorrhizal regulatory effects. In vitro assays showed that flavonoid extracts scavenged radicals at rates of 30.07–41.60% in hydroxyl radical (•OH), 71.89–78.06% in superoxide radical anion (O₂^•−), and 49.97–74.75% in 2,2-diphenyl-1-picrylhydrazyl (DPPH). Mycorrhizal symbiosis enhanced the antioxidant capacity of flavonoids, resulting in higher scavenging rates of •OH (19.07%), O₂^•− (5.00%), and DPPH (31.81%) under drought. Inoculated plants displayed reduced hydrogen peroxide (19.77%), O₂^•− (23.90%), and malondialdehyde (17.36%) levels. This study concludes that mycorrhizae promote the level of total flavonoids in trifoliate orange by accelerating the flavonoid biosynthesis pathway, hence reducing oxidative damage under drought. Full article

Global warming has resulted in an increase in the frequency of extreme high-temperature events. High temperatures can increase cell membrane permeability, elevate levels of osmotic adjustment substances, reduce photosynthetic capacity, impair plant growth and development, and even result in plant death. Under high-temperature stress, plants mitigate damage through physiological and biochemical adjustments, heat signal transduction, the regulation of transcription factors, and the synthesis of heat shock proteins. However, different plants exhibit varying regulatory abilities and temperature tolerances. Investigating the heat-resistance and regulatory mechanisms of plants can facilitate the development of heat-resistant varieties for plant genetic breeding and landscaping applications. This paper presents a systematic review of plant physiological and biochemical responses, regulatory substances, signal transduction pathways, molecular mechanisms—including the regulation of heat shock transcription factors and heat shock proteins—and the role of plant hormones under high-temperature stress. The study constructed a molecular regulatory network encompassing Ca²⁺ signaling, plant hormone pathways, and heat shock transcription factors, and it systematically elucidated the mechanisms underlying the enhancement of plant thermotolerance, thereby providing a scientific foundation for the development of heat-resistant plant varieties. Full article