Search Results (338)

The primary worldwide variables limiting plant development and agricultural output are the ever-present threat that environmental stressors such as salt (may trigger osmotic stress plus ions toxicity, which impact on growth and yield of the plants), drought (provokes water stress, resulting in lowering photosynthesis process and growth rate), heavy metals (induced toxicity, hindering physiological processes also lowering crop quantity and quality), and pathogens (induce diseases that may significantly affect plant health beside productivity). This review explores the integrated effects of these stressors on plant productivity and growth rate, emphasizing how each stressor exceptionally plays a role in physiological responses. Owing to developments in technology that outclass traditional breeding methods and genetic engineering techniques, powerful alleviation strategies are vital. New findings have demonstrated the remarkable role of nanoparticles in regulating responses to these environmental stressors. In this review, we summarize the roles and various applications of nanomaterials in regulating abiotic and biotic stress responses. This review discusses and explores the relationship between various types of nanoparticles (metal, carbon-based, and biogenic) and their impact on plant physiology. Furthermore, we assess how nanoparticle technology may play a role in practices of sustainable agriculture by reducing the amount of compounds used, providing them with a larger surface area, highly efficient mass transfer abilities, and controlled, targeted delivery of lower nutrient or pesticide amounts. A review of data from several published studies leads to the conclusion that nanoparticles may act as a synergistic effect, which can effectively increase plant stress tolerance and their nutritional role. Full article

Idesia polycarpa is a valuable woody oil plant with potential for horticultural and industrial applications. However, limited information is available regarding its drought tolerance during the seedling stage. In this study, one-year-old seedlings were subjected to five treatments based on soil relative water content (RWC): moderate drought (T1, 40 ± 5%), severe drought (T2, 20 ± 5%), control (CK, 70 ± 5%), and rewatering following moderate (T3) and severe drought stress (T4), with RWC restored to 70 ± 5%. Under drought stress, seedlings exhibited adaptive responses including reduced growth, enhanced antioxidant enzyme activity, osmotic regulation, and changes in endogenous hormone levels. Seedlings showed good tolerance and recovery under moderate drought, but severe drought caused substantial damage and limited post-rewatering recovery. Pearson correlation and principal component analyses revealed that betaine, APX, SA, IAA, ABA, chlorophyll (a + b) content, and crown growth were strongly associated with drought response and could serve as key indicators for drought resistance assessment in I. polycarpa. These findings provide insights into the physiological mechanisms of drought adaptation and support the development of a reliable evaluation system for drought tolerance in this promising species. Full article

The domesticated species currently available in the market have been developed through the breeding of wild relatives. Breeding strategies using wild relatives with high genetic diversity are attracting attention as an important approach for addressing climate change and ensuring sustainable food supply. However, studies examining gene expression variation in multiple wild and domesticated species are limited. Therefore, we aimed to investigate the changes in gene expression associated with domestication. We performed a meta-analysis of public gene expression data of domesticated species of rice, tomato, and soybean and their presumed ancestral species using 21 pairs for rice, 36 pairs for tomato, and 56 pairs for soybean. In wild relatives, the expression of genes involved in osmotic, drought, and wound stress tolerance was upregulated, with 18 genes included in the top 5% of DW scores. In domesticated species, upregulated expression was observed in genes related to auxin and those involved in the efflux of heavy metals and harmful substances, with 36 genes included in the top 5% of DW scores. These findings provide insights into how domestication influences changes in crop traits. Thus, our findings may contribute to rapid breeding and the development of new varieties capable of growing in harsh natural environments. Hence, a new cultivation method called “de novo domestication” has been proposed, which combines the genetic diversity of currently unused wild relatives and wild relatives with genome editing technologies that enable rapid breeding. Full article

Climate change has intensified drought stress, threatening global food security by affecting sensitive crops like maize (Zea mays). This study evaluated the potential of Antarctic fungal endophytes (Penicillium chrysogenum and P. brevicompactum) to enhance maize drought tolerance under field conditions with different irrigation regimes. Drought stress reduced soil moisture to 59% of field capacity. UAV-based multispectral imagery monitored plant physiological status using vegetation indices (NDVI, NDRE, SIPI, GNDVI). Inoculated plants showed up to two-fold higher index values under drought, indicating improved stress resilience. Physiological analysis revealed increased photochemical efficiency (0.775), higher chlorophyll and carotenoid contents (45.54 mg/mL), and nearly 80% lower lipid peroxidation in inoculated plants. Lower proline accumulation suggested better water status and reduced osmotic stress. Secondary metabolites such as phenolics, flavonoids, and anthocyanins were elevated, particularly under well-watered conditions. Antioxidant enzyme activity shifted: SOD, CAT, and APX were suppressed, while POD activity increased, indicating reprogrammed oxidative stress responses. Yield components, including cob weight and length, improved significantly with inoculation under drought. These findings demonstrate the potential of Antarctic endophytes to enhance drought resilience in maize and underscore the value of integrating microbial biotechnology with UAV-based remote sensing for sustainable crop management under climate-induced water scarcity. Full article

In arid agricultural production, exploring suitable water-saving irrigation strategies and analyzing their water-saving mechanisms are of great significance. Alternating partial root-zone drying irrigation (APRI), a water-saving strategy, enhances the water use efficiency (WUE) of alfalfa (Medicago sativa L.) This paper aims to clarify the physiological mechanisms by which the APRI method enhances the physiological WUE of alfalfa, as well as the differences between this water-saving irrigation strategy, conventional irrigation (CI), and their water deficit adjustments, in order to seek higher water use efficiency for alfalfa production in arid regions. In this experiment, alfalfa was used as the research subject, and three irrigation methods, CI, fixed partial root-zone drying (FPRI), and APRI, were set up, each paired with three decreasing moisture supply gradients of 90% water holding capacity (WHC) (W1), 70% WHC (W2), and 50% WHC (W3). Samples were taken and observed once after every three complete irrigation cycles. Through a comparative analysis of the growth status, leaf water status, antioxidant enzyme activity, and osmotic adjustment capabilities of alfalfa under different water supplies for the three irrigation strategies, the following conclusions were drawn: First, the APRI method, through artificially created periodic wet–dry cycles in the rhizosphere soil, provides pseudo-drought stress that enhances the osmotic adjustment capabilities and antioxidant enzyme activity of alfalfa leaves during the early to middle phases of irrigation treatment compared to CI and FPRI methods, resulting in healthier leaf water conditions. Secondly, the stronger drought tolerance and superior growth conditions of alfalfa under the APRI method due to reduced water availability are key factors in enhancing the water use efficiency of alfalfa under this strategy. Full article

Drought including both meteorological drought and water deficiency stress conditions is a major constraint on global agricultural productivity, particularly affecting Brassica species, which are vital oilseed and vegetable crops. As climate change intensifies, understanding plant responses to drought is crucial for improving drought resilience. Drought stress impacts Brassica crops at multiple levels, reducing germination rates, impairing physiological functions such as photosynthesis and water-use efficiency, and triggering oxidative stress due to the accumulation of reactive oxygen species. To counteract these effects, Brassica plants employ various adaptive mechanisms, including osmotic adjustment, antioxidant defense activation, and hormonal regulation. Recent research has explored molecular and physiological pathways involved in drought tolerance, revealing key physiological changes and biochemical markers that could be targeted for crop improvement. This review summarizes the latest findings on the physiological, biochemical, and molecular responses of Brassica crops to drought stress, with an emphasis on adaptive mechanisms and potential drought mitigation strategies. Additionally, future research directions are proposed, focusing on integrating molecular and agronomic approaches to enhance drought resilience in Brassica species. Full article

Salicornia species are halophytic plants that thrive in environments with moderate to high salinity. Owing to its high nutritional value and diverse bioactive constituents, Salicornia holds promise for applications in the food, feed, pharmaceutical, cosmetic, and bioenergy sectors. Understanding its salt tolerance mechanisms is important for developing crops suited to saline soils and water. Recent studies have revealed that Salicornia adapts to salinity through diverse physiological, biochemical, and molecular strategies. Despite these advances, a comprehensive synthesis of existing knowledge remains absent, hindering its effective application in crop improvement. In this review, recent advances in the understanding of Salicornia’s salinity tolerance are synthesized, with emphasis placed on key mechanisms: cell wall nano-mechanics, ion regulation and compartmentation, antioxidant defense, osmotic balance, phytohormonal control, signal transduction, transcriptional regulation, and the expression of salt-responsive proteins. The interactions among these mechanisms are also examined, along with their roles in conferring tolerance to additional abiotic stresses such as drought, submergence, and extreme temperatures. Finally, the potential applications of these findings in genetic engineering for improving salt tolerance in crops are discussed, along with proposed directions for future research to promote the use of halophytes in sustainable agriculture. Full article

Background: Drought stress is a major abiotic factor limiting Brassica juncea productivity, resulting in significant yield reductions. Plant Growth-Promoting Rhizobacteria (PGPR) have shown potential in enhancing drought tolerance; however, the metabolomic changes associated with their effects remain largely unexplored. This study examines the metabolic changes induced by a PGPR consortium (Enterobacter hormaechei, Pantoea dispersa, and Acinetobacter sp.) in two contrasting genotypes B. juncea (L.) Czern. ‘RH 725’ (drought tolerant) and B. juncea (L.) Czern. ‘RH-749’ (drought sensitive for drought tolerance, under both control and drought conditions. Methods: Metabolite profiling was conducted using gas chromatography-mass spectrometry (GC-MS) to identify compounds that accumulated differentially across treatments. We applied multivariate statistical methods, such as Partial Least Squares Discriminant Analysis (PLS-DA), hierarchical clustering, and pathway enrichment analysis, to explore metabolic reprogramming. Results: Drought stress induced significant changes in metabolite profile, particularly increasing the levels of osmoprotectants such as trehalose, glucose, sucrose, proline, and valine. Additionally, alterations in organic acids (malic acid and citric acid) and fatty acids (oleic acid and linoleic acid) were observed. PGPR inoculation further amplified these metabolic responses to enhance the osmotic regulation, reactive oxygen species (ROS) detoxification, and carbon-nitrogen metabolism, with RH-725 displaying a stronger adaptive response. Pathway enrichment analysis revealed that PGPR treatment significantly influenced metabolic pathways related to starch and sucrose metabolism, galactose metabolism, and amino acid biosynthesis, which play critical roles in drought adaptation. Conclusion: These findings provide insights into how PGPR contributes to stress resilience in B. juncea by modulating key biochemical pathways. This study provides new molecular insights into the known effect of PGPR for mitigating drought stress in oilseed crops. Full article

The fig (Ficus carica L.) is one of the oldest fruit crops cultivated in arid and semi-arid regions, valued for both its nutritional and economic importance; thus, ensuring sustainable fig production under climate change conditions is very important, as water scarcity increasingly affects fruit quality and production. Selecting and preserving resilient varieties among traditional varieties, representing centuries of local adaptation, is a vital strategy for addressing the challenges driven by climate change. In this context, this study assessed the physiological and biochemical parameters of the leaves of four fig landrace varieties (Fassi, Ghouddane, Nabout, and Ounq Hmam) grown in three different Mediterranean transitional zones of northern Morocco (Chefchaouen, Taounate, and Taza), during a single timepoint assessment conducted in late August 2023. The combined effects of location, variety, and their interactions on chlorophyll fluorescence (F_v/F_m), Soil Plant Analysis Development (SPAD) index, total chlorophyll content (ChlT), canopy temperature depression (CTD), proline content, protein content, total soluble sugar (TSS), hydrogen peroxide (H₂O₂), and malondialdehyde (MDA) were determined. Significant variation was observed among varieties and locations, with the location effect being observed for proline content, protein content, TSS, CTD, and ChlT, while variety had a stronger influence on SPAD, F_v/F_m, H₂O₂, and MDA. The results showed that Nabout and Ounq Hmam varieties had the greatest photosynthetic efficiency, as indicated by their elevated SPAD index, ChlT, and F_v/F_m values, and showed lower sensitivity to oxidative stress (low proline content, H₂O₂, and MDA levels). In contrast, Ghouddane and Fassi displayed better stress tolerance, presenting higher levels of oxidative stress markers. Among locations, Chefchaouen showed the highest protein, TSS, H₂O₂, and MDA levels, reflecting active stress tolerance mechanisms. These variations were confirmed by principal component analysis, which revealed a clear separation between photosynthetically efficient varieties (Nabout and Ounq Hmam) and stress-tolerant varieties (Ghouddane and Fassi). More than a conventional crop physiology study, this work highlights the adaptive strategies in traditional Mediterranean fig germplasm that could be crucial for climate change adaptation. While our findings are limited to a single season, they offer valuable, practical insights that can inform grower decision-making in the near term, especially when considered alongside local knowledge and additional research. Full article

Crop productivity is severely constrained by abiotic and biotic stresses, necessitating innovative strategies to enhance stress resilience. Glycerol-3-phosphate (G3P) is a central metabolite in carbohydrate and lipid metabolism, playing crucial roles in stress responses. In this study, we engineered a novel glycerol-3-phosphate dehydrogenase (GPDH) gene, designated OEGD, by fusing the N-terminal NAD-binding domain of rice OsGPDH1 with the feedback-resistant C-terminal catalytic domain of Escherichia coli gpsA. Overexpression of OEGD in rice enhanced tolerance to drought, phosphorus deficiency, high temperature, and cadmium (Cd²⁺) stresses, while also improving plant growth and yield under drought stress at the adult stage. Notably, the accumulation of glycerol-3-phosphate (G3P) and activities of antioxidant enzymes (SOD, POD, CAT) were significantly elevated in the transgenic plants following osmotic stimuli, and fatty acid profiles were altered, favoring stress adaptation. Transcriptomic analyses revealed that OEGD modulates cell wall biogenesis, reactive oxygen species (ROS) scavenging, and lipid metabolism pathways, with minimal disruption to core G3P metabolic genes. These findings highlight the potential of OEGD as a valuable genetic resource for improving stress resistance in rice. Full article

CLAVATA3 (CLV3)/endosperm surrounding region (CLE) peptides have been reportedly involved in plant growth and development, as well as responses to abiotic stresses. However, the stress resilience of most CLE genes in cotton remains largely unknown. Here, induced expression pattern analysis showed that GhCLE25 was obviously responsive to osmotic and salt treatments, indicating that GhCLE25 was involved in abiotic stress tolerance. Furthermore, silencing GhCLE25 or the exogenous application of CLE25p effectively led to reduced and enhanced drought tolerance, respectively, as indicated by the activities of the plants’ POD, SOD, CAT, and MDA contents, as well as their height and fresh weight. We found that the knockdown of GhCLE25 promoted seedling growth and development, with a higher plant height and fresh weight in GhCLE25-silenced plants in comparison to control plants. In addition, a comparative transcriptome analysis of TRV:00 versus TRV:GhCLE25 and Mock versus CLE25p revealed that the CLE25-mediated signaling pathway is mainly involved in defense response and phytohormone signaling. Collectively, these findings indicate diverse roles of CLE25 in regulating plant growth and response to environmental stimuli and highlight the potential utilization of CLE25 to improve drought stress in modern agriculture via CLE25p spraying. Full article

Poplars and aspens (Populus L. spp.) are undervalued options for use in managed landscapes. The genus comprises a multitude of taxa often negatively associated with disease susceptibility and short lifespans; however, it also hosts a diverse range of abiotic stress tolerances. The objective of this study was to generate a relative scale of the predicted drought tolerance of Populus spp. to inform site and taxon selection in managed settings. Utilizing vapor pressure osmometry, this study examined seasonal osmotic adjustment and predicted leaf water potential at the turgor loss point (Ψ_po) among several Populus taxa. All evaluated taxa demonstrated the ability to osmotically adjust (ΔΨ_π100) throughout the growing season. Bigtooth aspen (P. grandidentata Michx.) exhibited the most osmotic adjustment (−1.1 MPa), whereas black cottonwood (P. trichocarpa Torr. & A. Gray ex Hook.) exhibited the least (−0.44 MPa). Across the taxa, the estimated mean Ψ_po values in spring and summer were −1.8 MPa and −2.8 MPa, respectively. Chinese aspen (P. cathayana Rehder) exhibited the lowest Ψ_po (−3.32 MPa), whereas black cottonwood exhibited the highest (−2.47 MPa). The results indicate that drought tolerance varies widely among these ten Populus species and hybrids; bigtooth aspen and Chinese aspen are the best suited to tolerating drought in managed landscapes. Full article

Maize (Zea mays L.) is a staple cereal crop worldwide, but its productivity is significantly affected by extreme weather conditions such as drought and heat stress. Plant growth, physiological processes, and yield potential are all affected by these conditions; as such, resilient maize crops are required to tackle these abiotic challenges. With an emphasis on morphological, physiological, and biochemical reactions, this review paper investigates the processes that underlie resistance to certain environmental challenges. Features including deep root systems, osmotic adaptations, and antioxidant enzyme activity help maize withstand drought. Activation of drought- and heat-responsive genes, accumulation of osmoregulatory compounds, and changes in membrane fluidity are all components of abiotic stress tolerance. Likewise, improved transpiration efficiency, modified photosynthetic processes, and improved heat shock proteins are used to produce heat resistance. Enhancing resilience requires progress in breeding methods, genetic engineering, and agronomic techniques, such as the use of stress-tolerant cultivars, biotechnology interventions, and climate-smart agriculture tactics. A special focus was given to cutting edge technologies like CRISPER-Cas9-mediated recent advances in heat and drought resistance. This review sheds light on recent studies and potential avenues for enhancing resilience to harsh climatic conditions, guaranteeing food security in the face of climate change. Full article

Climate-change-induced drought threatens forest restoration by limiting seedling establishment. To address this, we developed synthetic bacterial communities (SynComs) tailored to support drought tolerance in two Mediterranean tree species, Quercus pubescens and Sorbus domestica. Bacteria were isolated from forest soil exposed to long-term drought, sampling across soil depths and root-associated compartments. We selected strains with key plant-beneficial traits, including exopolysaccharide (EPS) production, hormone synthesis (auxin, ABA), siderophore release, and osmotic tolerance. SynComs were assembled based on functional complementarity and ecological origin. Biofilm assays showed that even weak individual producers could enhance community-level performance. After initial screening on Arabidopsis thaliana, the most and least effective SynComs were tested on Q. pubescens and S. domestica seedlings. Compared to controls, the best-performing SynComs reduced the proportion of drought-symptomatic seedlings by 47% in Q. pubescens and 71% in S. domestica, outperforming single-strain inoculants. Notably, EPS-rich SynCom B aligned with the conservative root traits of Q. pubescens, while hormone-rich SynCom F matched the acquisitive strategy of S. domestica. Predictive modeling identified bacterial identity and symptom timing as key predictors of drought resilience. Our results highlight the value of matching microbial traits with plant strategies and drought context for climate-smart forest restoration. Full article

Elevated temperatures and extended drought periods are driving significant changes in the structure and function of forest ecosystems. High-elevation alpine ash forests (Eucalyptus delegatensis R.T. Baker) in Australia are an example of forests that are already impacted by climate change. These obligate seeder forests can shift to non-forest ecosystems following extreme drought and altered fire regimes, raising concern about their adaptation to a rapidly changing environment and long-term forest persistence. Plant functional traits play a major role in determining adaptive mechanisms to environmental conditions. While alpine ash forests are vulnerable to climate change, it is unclear if different provenances have adapted to the climatic conditions in which they grow. We therefore studied the variation in expression of functional traits related to drought tolerance in 21 provenances of alpine ash distributed across an environmental gradient. We investigated if functional traits varied between the provenances and were related to climate of origin in order to identify provenances that may be better adapted to drought. We measured the following traits in a common garden experiment under well-watered conditions: stomatal density, specific leaf area, minimum stomatal conductance and osmotic potential at full turgor. There was very little variation in trait expression between the 21 provenances for all functional traits related to drought tolerance. All provenances had medium-range stomatal density (170–300 stomata mm²) and specific leaf area (SLA, 50–70 cm² g⁻¹), a very low minimum stomatal conductance (2–4 mmol m² s⁻¹) and a high osmotic potential at full turgor (−0.6–0.7 MPa). There was no statistically significant correlation of trait expression with the climate of origin. Thus, there is very little evidence for genetically controlled differences in trait expression of drought tolerance traits in this species. It is likely that the high elevation and high rainfall environment of the species’ ecological niche has not been subjected to frequent and extensive drought periods that would elicit an evolutionary pressure selecting for drought-tolerant traits. We could not identify provenances that would have different drought-tolerant functional trait responses than others, potentially conferring an adaptive advantage under climate change. This has implications for using climate-adjusted provenancing to improve resilience in alpine ash forests predicted to experience more frequent and severe droughts in the future. Full article