Search Results (112)

Anaerobic germination (AG) is a pivotal trait for successful direct-seeded rice cultivation, encompassing rainfed and irrigated conditions. Elite rice cultivars are often vulnerable to flooding during germination, resulting in poor crop establishment. This drawback has led to the exploration of AG-tolerant rice landraces, which offer valuable insights into the genetic underpinnings of AG tolerance. Over the years, substantial progress has been made in identifying significant quantitative trait loci (QTLs) associated with AG tolerance, forming the basis for targeted breeding efforts. However, the intricate gene regulatory network governing AG tolerance remains enigmatic. This comprehensive review presents recent advances in understanding the physiological and genetic mechanisms underlying AG tolerance. It focuses on their practical implications in breeding elite rice cultivars tailored for direct-seeding systems. Full article

Understanding the alterations to the shoot and root traits of rapeseed (Brassica napus) in response to salt stress is vital for improving its ability to thrive in saline-prone regions. This research aims to evaluate the responses of shoot and root traits of rapeseed at the vegetative stage under salt- and salicylic acid-induced stress in hydroponic culture. Five parents and ten F₃ segregants of rapeseed were subjected to three treatments: T1: control, T2: 8 dSm⁻¹ salt, and T3: 8 dSm⁻¹ salt + 0.1 mM salicylic acid at 21 days of age. Salinity stress significantly reduced the estimated root surface area by 54% compared to control, highlighting the plasticity of roots under stress. The simultaneous application of salt and SA did not alleviate the salinity stress, but rather reinforced the degree of stress and decreased the number of leaves, diameter of the main axis, chlorophyll content, and estimated root surface area by 18.5%, 15.4%, 38.8%, and 23%, respectively, compared to T2. The parental genotype M-245 followed by F₃ genotype M-232×M-223 accounted for the higher overall estimated root surface area. These results provide novel insights into the responses of root traits in rapeseed breeding lines under dual treatment, which hold promising implications for future rapeseed breeding efforts focused on sustainable rapeseed production. Full article

Fungi, from saprophytes to pathogens, face predictable daily fluctuations in light, temperature, humidity, and nutrient availability. To cope, they have evolved an internal circadian clock that confers a major adaptive advantage. This review critically synthesizes current knowledge on the molecular architecture and physiological relevance of fungal circadian systems, moving beyond the canonical Neurospora crassa model to explore the broader phylogenetic diversity of timekeeping mechanisms. We examine the core transcription-translation feedback loop (TTFL) centered on the FREQUENCY/WHITE COLLAR (FRQ/WCC) system and contrast it with divergent and non-canonical oscillators, including the metabolic rhythms of yeasts and the universally conserved peroxiredoxin (PRX) oxidation cycles. A central theme is the clock’s role in gating cellular defenses against oxidative, osmotic, and nutritional stress, enabling fungi to anticipate and withstand environmental insults through proactive regulation. We provide a detailed analysis of chrono-pathogenesis, where the circadian control of virulence factors aligns fungal attacks with windows of host vulnerability, with a focus on experimental evidence from pathogens like Botrytis cinerea, Fusarium oxysporum, and Magnaporthe oryzae. The review explores the downstream pathways—including transcriptional cascades, post-translational modifications, and epigenetic regulation—that translate temporal signals into physiological outputs such as developmental rhythms in conidiation and hyphal branching. Finally, we highlight critical knowledge gaps, particularly in understudied phyla like Basidiomycota, and discuss future research directions. This includes the exploration of novel clock architectures and the emerging, though speculative, hypothesis of “chrono-therapeutics”—interventions designed to disrupt fungal clocks—as a forward-looking concept for managing fungal infections. Full article

This study was conducted to examine the combined effects of monensin (MS) and 3 µm polystyrene microplastics (PEMPs) on the growth and stress-associated physiological responses of Microcystis aeruginosa under controlled laboratory conditions [temperature: 20 ± 1 °C, lighting: (30 ± 4) µmol m⁻² s⁻¹ (12 h:12 h light–dark photoperiod), growth medium: BG-11]. The experiments included MS concentrations of 0, 50, 250, and 500 µg/L and PEMPs concentrations of 0.25, 1.25, and 6 mg/L. Measurements included optical density (OD₇₃₀), chlorophyll ‘a’, cellular protein content, oxidative stress, and the activities of catalase (CAT) and guaiacol peroxidase (GPX). M. aeruginosa exhibited a significant increase in growth on day 7 at elevated MS concentrations across all PEMP levels. Similarly, MS and PEMP treatments had a significant interactive effect on cellular protein content on day 7. However, their combined effect on chlorophyll ‘a’ production was not significant. Oxidative stress measurements showed a dose-dependent decrease with increasing MS concentrations under PEMP administrations. Enzyme activity assays indicated that CAT activity increased while GPX activity decreased with higher MS concentrations. The results imply that co-contamination of PEMPs and MS has a significant impact on the growth and stress physiology of M. aeruginosa in aquatic ecosystems. Full article

Abiotic stresses are the major factors limiting grape production in the world. They significantly impede grape growth and production. However, during the grape production stage, plant growth regulators play a crucial role in regulating grape developmental progress, especially methyl jasmonate (MeJA). The exogenous MeJA participates in different crop production, gene expression, signaling transduction, natural defense, stress resistance, hormone balance, osmotic regulation, cellular metabolic process, and thermostatic regulation. Grape crop resilience to different abiotic and biotic stresses was overall fascinated by exogenous applications of MeJA. Therefore, in this review, we focus on the MeJA hormone in abiotic stress relief and discovery, application, significance, occurrence, growth via development, stress responses, interaction, molecular modulation, and biological signaling in the grape. Exogenous MeJA in abiotic stress responses explained the physiological change and the signaling pathway has emerged as one of the key plant metabolic processes vs. photosynthetic productivity, playing a substantial role in gene expression, quality parameters, fruit attribution, protein differentiation, cellular programming, and reprogramming, and tolerance mechanism. MeJA hormone has been discovered after a broader study as abiotic stress-responsive methyl jasmonate/Jasmonic acid, which could be a pivotal target not only for grape production but also for other crops. Full article

From germination to harvest, cereal crops are constantly exposed to a broad spectrum of abiotic stresses that significantly hinder their growth and productivity, posing a serious threat to global food security. Seed resilience and performance are foundational to sustainable agriculture, making the development of efficient, low-cost, and environmentally friendly strategies to enhance seed vigor and stress tolerance a critical priority. Seed priming has emerged as a promising pre-sowing technique that involves exposing seeds to specific organic or inorganic compounds under controlled conditions to improve their physiological and biochemical traits. Various priming techniques—including halopriming, chemical priming, osmopriming, hormonal priming, hydropriming, biopriming, and nanopriming—have been successfully applied in cereal crops to alleviate the adverse effects of environmental stressors. These treatments trigger a cascade of metabolic and molecular responses, including the modulation of hormonal signaling, enhancement of antioxidant defense systems, stabilization of cellular structures, and upregulation of stress-responsive genes. Together, these changes contribute to enhanced seed germination, improved growth and performance, and greater adaptability to abiotic stress conditions. This review provides a comprehensive overview of seed priming strategies in cereal crops, emphasizing their mechanisms of action and their impact on plant performance in challenging environments. Full article

The present research was designed to assess the potential effect of SNP to alleviate salinity stress injury in fig transplants cv. Conadria. One-year-old transplants irrigated with saline water (6.25 ds/m) were treated with sodium nitroprusside (SNP) at four concentrations (0, 50, 100 and 200 µM); untreated transplants exposed to salt stress represent the positive control, while the non-stressed transplants represent the negative control. Salt stress showed a considerable increase in lipid peroxidation, proline, sodium, chloride content and antioxidant enzyme activity and reduced vegetative growth parameters, photosynthetic pigments, phenolic content and K/Na ratio. SNP reduced salt stress injury in fig transplants through maintaining higher values of growth parameters and photosynthetic pigment content, reducing sodium accumulation and maintaining the integrity of cell membrane lipids. SNP-treated transplants accumulated higher amounts of potassium ions and a higher K/Na ratio. SNP at 100 µM was the most efficient treatment in enhancing the response to salt stress. Overall, the results show that SNP application is a promising practice for alleviating salt stress on fig transplants. Full article

Plant-growth-promoting rhizobacteria (PGPR) influence soil fertility, plant growth, tolerance to abiotic stress, resistance to herbivorous insects, and plant interactions with other organisms. While the effects of PGPR on plant growth, fruit yield, and induced defense responses have been extensively studied, the consistent positive outcomes have fueled rapid expansion in this research field. To evaluate PGPR impacts on plant growth and interactions with phytophagous insects, we conducted a systematic meta-analysis using publications from electronic databases (e.g., PubMed, Web of Science) that reported PGPR effects on plants and insects. Effects were categorized by plant family, PGPR genus, insect feeding guild, and insect–host specialization. Our analysis revealed that PGPR generally enhanced plant growth across most plant families; however, the magnitude and direction of these effects varied significantly among PGPR genera, indicating genus-specific interactions with host plants. When assessing PGPR-mediated reductions in phytophagous insects, we found that Pseudomonas, Rhizobium, and Bacillus exhibited the weakest negative effects on insect populations. PGPR significantly reduced both monophagous and polyphagous insects, with the most pronounced negative impacts on sucking insects (e.g., aphids, whiteflies). This study highlights critical patterns in PGPR-mediated plant growth promotion across taxa and the related differential effects on phytophagous insect activity. These insights advance our understanding of PGPR applications in agroecological production systems, particularly for integrated pest management and sustainable crop productivity. Full article

Soil microorganisms provide multifaceted benefits, including maintaining soil nutrient dynamics, improving soil structure, and instituting decomposition, all of which are important to soil health. Unpredictable weather events, including flooding from heavy rainfall, flash floods, and seawater intrusion, profoundly impact soil ecology, which is primarily challenged by flooding stress, and imbalances these microbial communities and their functions. This disturbance impairs the symbiotic exchanges between microbes and plants by limiting root exudates and habitats for microbes, as well as nutrient acquisition efficiency for plants. Therefore, this review comprehensively examines the changes in soil microbial communities that occur under flooding conditions. Flooding reduces soil oxygen (O₂) levels, limiting aerobic microbes but promoting anaerobic ones, including potential pathogens. In flooded soil, O₂ deficiency indirectly depends on the size of the soil particles and water turbidity during flooding. O₂ depletion is critical in shaping microbial community adaptation, which is linked to variations in soil pH, nutrient concentrations, and redox status, and fresh and saline water vary differently in terms of the adaptation of microorganisms. Wet soil alters soil enzyme activity, which influences microbial community composition. Notably, three-month post-flooding conditions allow microbial communities to adapt and stabilize more effectively than once-weekly flooding frequency. Based on the presence of aboveground species, fungi are found to reduce under flooding conditions, while nematode numbers, surprisingly, increase. Direct and indirect impacts between soil microbes and physio-chemical properties indicate positive or negative feedback loops that influence the soil ecosystem. Over the years, beneficial microorganisms such as plant-growth-promoting microbes (PGPMs) have been identified as important in regulating soil nutrients and microbial communities in wetland environments, thereby enhancing soil health and promoting better plant growth and development. Overall, understanding the mechanisms of belowground ecosystems under flooding conditions is essential for optimizing agricultural practices and ensuring sustainable crop production in flood-prone areas. Full article

Abiotic stresses like heat and salinity challenge crop production, but cultivar-specific adaptability and tolerance inducers can mitigate their impact. This study examined the growth and biochemical responses of five tomato varieties (Adeleza F1, Saint Anna F1, Goudski F1, Bronski F1, and Dunk F1) to thermopriming followed by salinity stresses. Thermopriming initially promoted growth but had variable effects on plant performance under combined stresses. Adeleza F1 and Bronski F1 were less affected, while Goudski F1 and Dunk F1 exhibited delayed development and reduced biomass under salinity stress. Thermopriming enhanced leaf chlorophyll content and antioxidant capacity in some varieties but inconsistently influenced leaf phenolics and flavonoids. Notably, increased flavonoid and anthocyanin accumulation in certain varieties suggests improved stress tolerance, albeit at the cost of growth. However, a consistent priming effect was not observed across all varieties, as combined heat and salt stress had a more severe impact than individual stresses. These findings highlight genotype-specific responses, underscoring the need for optimized (thermo-)priming protocols that balance growth and defense. This study provides valuable insights into the complex interplay of heat and salinity stress in tomatoes, emphasizing targeted strategies for enhancing crop resilience and informing future breeding programs. Full article

Mushrooms play an important role in ecosystem sustainability and are highly valued in medicine and human nutrition. Using AAS and biochemical methods of analysis, the antioxidant status and mineral composition of seven mushroom species (Armillaria mellea, Xeromocus illudens, Leccinum aurantiacum, Leccinum scrabum, Lactarium pubescens, Rusula vesca, and Lycoperpon molle Pers.) gathered near the Pechenganikel smelting plant in the Pasvik Nature Reserve of the Murmansk region were evaluated. The concentrations of Ni and Cu in the fruiting bodies of mushrooms were in the ranges of 0.43–39.7 and 7.9–45.9 mg kg⁻¹ d.w., respectively. An unusually high biological concentration factor (BCF) for Ni, Cu, and Zn levels in mushrooms grown in soils with a low amount of these elements indicates the low suitability of the mentioned parameter for mushroom characteristics in territories with an uneven distribution of elements in soil. On the other hand, selenium (Se) showed high BCF levels, exceeding 1, for all mushrooms tested, with the highest values associated with L. saccatum (5.17) and the lowest values with A. mellea (1.36). A significant excess (3.4) of the Recommended Daily Allowance (RDA) level per 30 g of dry mushrooms was recorded for Ni in Russula vesca gathered 6 km from the Ni/Cu smelting plant, and 1.3 excess of the RDA was recorded in L. scrabum grown in the vicinity of the Shuonyoka waterfall. No RDA excess was revealed for Cu. Positive correlations between Se, polyphenol content, and total antioxidant activity (AOA) (r = 0.915–0.926; p < 0.001) and a negative correlation between Cu–Se and Cu–AOA in Leccinum species indicate the important role of antioxidant defense and Se, particularly in Arctic mushroom growth and survival, providing a specific protection of mushrooms against Cu toxicity. Full article

Bacillus halotolerans, a halophilic bacterial species of the genus Bacillus, is emerging as a biological control agent with immense potential for sustainable agriculture, particularly in extreme conditions and environmental rehabilitation. This review summarizes the current state of research on B. halotolerans, emphasizing its diverse applications in the biocontrol of plant pathogens, plant growth promotion under salinity stress, nematode management, and bioremediation. B. halotolerans utilizes several mechanisms such as the production of siderophores and phytohormones, secretion of exopolysaccharides, and the release of antifungal and nematicidal compounds, which allows it to mitigate both abiotic and biotic stresses in various crops, including wheat, rice, date palm, tomato, and others. In addition, genomic and metabolomic analyses have revealed its potential for secondary metabolite production that improves its antagonistic and growth-promoting traits. Despite significant progress, challenges remain in translating laboratory results into field applications. Future research should focus on formulating effective bioinoculants and field trials to maximize the practical utility of B. halotolerans for sustainable agriculture and environmental resilience. Full article

Climate change significantly impacts agriculture by increasing the frequency and intensity of environmental stresses, which can severely reduce agricultural yields. Adopting sustainable practices is crucial to mitigating these risks and enhancing crop resilience. Applying natural compounds and microorganisms as biostimulants has gained popularity as an eco-friendly approach to alleviating abiotic stress in agricultural plants. This study reviews the current research on applying biostimulants in horticulturally significant crops to boost their resistance to abiotic stressors such as salinity, drought, and high temperatures. It explores the mechanisms through which these stimulants offer protection, focusing on the roles of key bioactive substances in regulating physiological and molecular processes for stress adaptation. The study addresses biostimulant formulation, regulation, and application challenges. Future research directions are suggested to harness biostimulants’ potential fully, aiming to develop climate-resilient horticultural systems that follow sustainability principles. This comprehensive review underscores the use of biostimulants as a sustainable strategy to increase crop yields in the face of climate change, reducing reliance on synthetic agrochemicals. Full article

Pseudanabaena foetida, a filamentous cyanobacterium, is highly sensitive to temperature and light intensity. This study explores its oxidative stress responses under diurnal light intensities in temperature variations, utilizing hydrogen peroxide (H₂O₂) normalized to optical density (OD₇₃₀) levels (H₂O₂/OD₇₃₀) as a biomarker. The adequate P. foetida cells were distributed to three incubators for 22 days at 30 °C, 20 °C, and 10 °C. Light intensity varied over the course of the day, increasing from morning to a maximum at noon, followed by a gradual decrease until evening. Measurements of H₂O₂, protein, chlorophyll a (Chl a), and catalase (CAT) activity were carried out every three hours, starting at 6:00 and ending at 21:00. Protein concentration and Chl a increased between 12:00 and 15:00 for every temperature. H₂O₂, CAT, and H₂O₂/OD₇₃₀ increased until 15:00 and decreased afterwards for each temperature. The CAT was directly proportional to P. foetida’s H₂O₂ concentration or cell biomass (H₂O₂/OD₇₃₀), which indicates oxidative stress responses and a defense mechanism. The reduced temperature (30 °C to 20 °C and 30 °C to 10 °C) was significantly impactful on H₂O₂ concentration, protein concentration, and Chl a content. The model, based on P. foetida biomass, provides valuable insights into oxidative stress responses under different temperatures, with implications for understanding climate change. Full article

The advancement of global warming and climate change requires strategic actions in understanding and seeking interactions between plant species and microorganisms that are more tolerant to water deficit. This research assessed the morpho-agronomic, physiological, and gene expression responses of two Passiflora cincinnata accessions (tolerant and sensitive) to water deficit, focusing on their relationship with mycorrhization. A randomized design with two accessions, two field capacities, and four AMF inoculation treatments was used to compare drought and control conditions. Differential gene expression was analyzed under drought stress, and the effect of mycorrhization on stress tolerance was evaluated. The results showed that inoculation with native arbuscular mycorrhizal fungi (AMF) communities, especially those from water-deficit conditions (AMF25), resulted in greater increases in height, number of leaves, stem diameter, number of tendrils, leaf area, and fresh biomass of root and shoot, with increases ranging from 50% to 300% compared to the control (non-inoculated) and monospecific inoculation (Entrophospora etunicata). Higher photosynthetic rate and water use efficiency were observed in the tolerant accession. Mycorrhizal inoculation increased the total chlorophyll content in both accessions, especially when inoculated with native AMF communities. Overall, P. cincinnata showed higher mycorrhizal responsiveness when inoculated with native AMF communities compared to monospecific inoculation with E. etunicata. The tolerant accession showed overexpression of the genes PcbZIP, PcSIP, and PcSTK, which are associated with signal transduction, water deficit tolerance, osmoregulation, and water transport. In contrast, the water deficit-sensitive accession showed repression of the PcSIP and PcSTK genes, indicating their potential use for distinguishing tolerant and sensitive accessions of the species. The tolerance of P. cincinnata to water deficit is directly related to physiological responses, increased photosynthetic rate, efficient water use, and regulation of gene expression. Full article