Search Results (63)

Seed priming has been widely used as a strategy to improve germination and promote uniform seedling growth in horticultural crops, yet its application in microgreen production remains relatively underexplored. This study evaluated the impact of four priming treatments—hydrogen peroxide, Kelpak Maxx (a seaweed extract), Continuum^TM (a beneficial bacterial biostimulant), and hydropriming—on the germination, shoot growth, visual quality, coloration, and mineral nutrient composition of four herbal microgreen species compared with untreated raw seeds as a control treatment. Four species—chives (Allium schoenoprasum), dill (Anethum graveolens), scallion (Allium fistulosum), and shiso (Perilla frutescens)—were produced as microgreens under greenhouse conditions in two experiments in 2024 and 2025. Results revealed that early germination percentages at 3 days after treatment (DAT) in dill were increased by Kelpak Maxx, Continuum, and hydropriming by 11–18% in 2024 and by 20–40% in 2025, compared with increases for the control of 1% in 2024 and 5% in 2025. Germination percentages at 7 DAT in chives, scallion, and shiso all exceeded 88%, which were similar among priming treatments in 2024 and were not affected by priming in 2025. The four priming treatments resulted in similar fresh and dry shoot weights in chives, scallion, and shiso, but decreased fresh shoot weights in dill by 48.6% in 2024 and by 26.2% in 2025 compared with the control treatment. Species varied in mineral nutrient compositions. Priming altered concentrations of potassium, sulfur, magnesium, boron, and copper in certain species, but otherwise had minimal effects on mineral nutrient concentrations. Seed priming may potentially be used to enhance germination in slow-germinating species; however, it did not consistently improve shoot yield or mineral nutrient concentrations in the four tested microgreen species. Full article

The production of pre-basic (G0) seed tubers underpins the certified potato value chain. However, the transition from in vitro laboratory conditions to the ex vitro greenhouse environment remains a persistent production constraint, with reported mortality rates of 50–70%. This systematic review, conducted in accordance with PRISMA 2020 guidelines, synthesizes data from 63 selected studies (spanning 2010–2026) to propose a conceptual “Physiological Competence Framework”. We introduce a conceptual hypothesis termed the “Nitrogen Paradox”, which suggests that excessive ammonium influx may inhibit lignin biosynthesis, explaining the structural vulnerability of the vitrotype. Our analysis proposes three pillars for acclimatization success: (1) Nutritional hardening and exogenous PGR modulation, characterized by reduced nitrogen and sucrose levels to mitigate hyperhydricity; (2) photo-autotrophic induction, where optimized LED spectra replace conventional lighting to stimulate stomatal functionality; and (3) rhizosphere engineering, utilizing bio-priming with Plant Growth-Promoting Rhizobacteria (PGPR) to create a biotic shield against transplant shock. Furthermore, we examine emerging evidence for nanoparticle-based stress priming (AgNPs, ZnNPs). The evidence supports replacing high-nitrogen multiplication media with reduced-nitrogen formulations, replacing fluorescent lamps with balanced Red–Blue LED spectra, and incorporating PGPR bio-priming before transplant. Full article

Seed biopriming is increasingly recognized as a strategy capable of inducing molecular memory that enhances plant performance under heavy-metal stress. Here, we investigated how biopriming Silene sendtneri seeds with Paraburkholderia phytofirmans PsJN establishes a transcriptional state that predisposes seedlings for improved cadmium (Cd) tolerance. RNA-seq profiling revealed that primed seeds exhibited differential gene expression prior to Cd exposure, with strong upregulation of detoxification enzymes, antioxidant machinery, metal transporters, photosynthetic stabilizers, and osmoprotectant biosynthetic genes. Enrichment of gene ontology categories related to metal ion detoxification, redox homeostasis, phenylpropanoid metabolism, and cell wall organization indicated that biopriming imprints a preparatory transcriptional signature resembling early stress responses. Upon Cd exposure, primed plants displayed enhanced physiological performance, including preserved integrity, elevated antioxidant activity, particularly peroxidases in roots, higher osmolyte accumulation, stabilized micronutrient levels, and substantially increased Cd uptake and sequestration. These coordinated responses demonstrate that biopriming induces a sustained molecular memory that accelerates and strengthens downstream defense activation. These findings demonstrate that PGPR-based biopriming establishes a stable transcriptomic memory in seeds that enhances cadmium tolerance, metal sequestration, and stress resilience, highlighting its potential for improving hyperaccumulator performance in phytoremediation and stress adaptation strategies. Full article

Aims: The plant and soil microbiome serve as a reservoir of beneficial endophytic bacteria, including plant-growth-promoting (PGP) Bacillus subtilis, which enhances nutrient acquisition and protects plants against environmental stresses. We isolated novel bacteria from cultivated peanut plants selected from agricultural fields that survived a season of water scarcity and high temperatures. Experiments were conducted to determine whether plant survival was partially attributable to the presence of beneficial microbes that could be harnessed for future biotechnology applications. Methods and Results: Seven bacterial isolates of Bacillus spp. were identified through 16S rRNA sequencing, revealing close affiliations to B. subtilis, B. safensis, and B. velezensis. Growth curve analysis and colony morphology characterization revealed distinct growth patterns across different media types, while phytohormone production assays demonstrated variable indole-3-acetic acid (IAA) synthesis among isolates. When applied as seed biopriming agents to two hybrid peanut varieties, bacterial inoculation significantly enhanced root surface area and root tip development, with B. subtilis-TAM84A showing the most pronounced effects on ‘Schubert’ roots. In addition, vegetative growth assessments indicated increased branch numbers and plant height, particularly with treatments with B. velezensis strains TAM6B and TAM61A, and a consortium of all isolates. Under drought conditions, inoculated plants exhibited delayed wilting and improved recovery after rehydration, indicating enhanced drought resilience. Conclusions: Several local Bacillus strains recovered from drought-tolerant peanut plants showed improved growth and drought tolerance in greenhouse-grown peanut plants. Ongoing field studies aim to evaluate the potential of regionally adapted microbial populations as soil amendments during planting. Impact Statement: This study demonstrates that local strains of Bacillus isolated from drought-resistant peanut plants possess significant potential as bioinoculants to improve growth and drought tolerance in potted peanut plants. This work provides a foundation for utilizing regionally adapted microbial populations to address agricultural challenges related to water scarcity. Full article

Although purple non-sulfur bacteria (PNSB) have been studied as good biofertilizers, their direct effects on maize seed vigor remain unclear. Additionally, the seedling stage is a vital factor for the later growth of maize. This study was conducted to evaluate the effectiveness of potassium-solubilizing PNSB (K-PNSB) in enhancing the vigor of hybrid maize seeds. A completely randomized design was employed, incorporating single strains, Luteovulum sphaeroides M-Sl-09, Rhodopseudomonas thermotolerans M-So-11, and Rhodopseudomonas palustris M-So-14, as well as a mixture of all three strains. Each was tested at bacterial suspension dilution ratios with sterile distilled water of 1:2000; 1:2250; 1:2500; 1:2750; and 1:3000 (v/v), with three replications per treatment. Each replicate consisted of a Petri dish containing 10 hybrid maize seeds of each hybrid of LVN 10, C.P. 511, and NK7328 Gt/BT, and was incubated for five days. The results showed that K-PNSB significantly enhanced root and shoot development compared to the control (p < 0.05). The 1:2500 dilution of the individual strains and the mixture notably improved germination rate, root length, shoot length, and seedling vigor index compared to the control. At the 1:2500 dilution, the improved vigor index increased by 73.5% for L. sphaeroides, 48.7% for R. thermotolerans, 47.4% for R. palustris, and 78.5% for the mixed inoculum in the LVN 10 hybrid. Similar trends were observed for C.P. 511 and NK7328 hybrids, confirming strain- and hybrid-specific responses. The findings highlight that K-PNSB can serve as effective bio-priming agents to enhance maize seed vigor through mechanisms related to potassium solubilization and phytohormone production. Field-scale validation is recommended to assess their long-term agronomic potential. Full article

Seed priming, traditionally viewed as a method for enhancing crop resilience to abiotic stress, has evolved into a multifaceted agronomic strategy. This review synthesizes the current findings demonstrating that priming influences plant development, metabolic regulation, and yield enhancement even under optimal conditions. By covering a wide range of crops, including cereals (e.g., wheat, maize, rice, and barley) as well as vegetables and horticultural species (e.g., tomato, carrot, spinach, and lettuce), we highlight the broad applicability of priming across agricultural systems. The underlying mechanisms include hormonal modulation, altered source–sink dynamics, accelerated phenology, and epigenetic memory. Various priming techniques are discussed, including hydropriming, osmopriming, biopriming, chemopriming, and nanopriming, with attention to their physiological and molecular effects. Special focus is given to the role of seed priming in advancing climate-smart and precision agriculture. By shifting the narrative from stress mitigation to holistic crop performance optimization, seed priming emerges as a key tool for sustainable agriculture in the face of global challenges. Full article

The hard-seed coat of Ormosia henryi significantly impedes germination efficiency in massive propagation, while conventional physical dormancy-breaking methods often result in compromised seed vigor, asynchronous seedling emergence, and diminished stress tolerance. Seed biopriming, an innovative technique involving the inoculation of beneficial microorganisms onto seed surfaces or into germination substrates, enhances germination kinetics and emergence uniformity through microbial metabolic functions and synergistic interactions with seed exudates. Notably, spermosphere-derived functional bacteria isolated from native spermosphere soil demonstrate superior colonization capacity and sustained bioactivity. This investigation employed selective inoculation of these indigenous functional strains to systematically analyze dynamic changes in endogenous phytohormones, enzymatic activities, and storage substances during critical germination phases, thereby elucidating the physiological mechanisms underlying biopriming-enhanced germination. The experimental results demonstrated significant improvements in germination parameters through biopriming. Inoculation with the Bacillus sp. strain achieved a peak germination rate (76.19%), representing a 16.19% increase over the control (p < 0.05). The biopriming treatment effectively improved the seed vigor, broke the impermeability of the seed coat, accelerated the germination speed, and positively regulated physiological indicators, especially amylase activity and the ratio of gibberellic acid to abscisic acid. This study establishes a theoretical framework for microbial chemotaxis and rhizocompetence in seed priming applications while providing an eco-technological solution for overcoming germination constraints in O. henryi cultivation. The optimized biopriming protocol addresses both low germination rates and post-germination growth limitations, providing technical support for the seedling cultivation of O. henryi. 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

Seed science is the comprehensive study of seeds. It encompasses their biology, production, technology, genetics, physiology, ecology, and applications in agriculture and conservation. Seed science has undergone transformative advancements through the integration of microbial technologies, with beneficial microorganisms emerging as critical tools for enhancing germination, seedling vigor, and crop resilience. Research demonstrates that microbial treatments improve nutrient uptake, hormonal regulation, and stress tolerance while establishing early symbiotic relationships with plants. This review synthesizes recent advances in understanding the roles of beneficial microbes in seed science, focusing on their impact on seed germination, seedling growth, and plant health. We explore the composition and transmission of seed microbiomes, highlighting the vertical transfer of microbes from parent plants to seeds and the influence of environmental factors on microbial community structure. The review also discusses innovative approaches to seed microbiome engineering. Particular attention is given to seed biopriming with plant growth-promoting bacteria (PGPB), which has shown significant potential in improving germination rates, seedling vigor, and crop productivity. Specific microbial strains, such as Trichoderma species and Pseudomonas fluorescens, are discussed with emphasis on their mechanisms of action in enhancing plant performance. The review also addresses the impact of breeding on seed microbiomes and explores emerging research directions, including the development of tailored microbial inoculants and the investigation of intracellular seed bacteria. By synthesizing these findings, this review aims to provide a comprehensive summary of the current state of seed microbiome research and its implications in seed science for sustainable agriculture. Full article

Plant growth-promoting bacteria (PGPB) are free-living microorganisms that actively reside in the rhizosphere and affect plant growth and development. These bacteria employ their own metabolic system to fix nitrogen, solubilize phosphate, and secrete hormones to directly impact the metabolism of plants. Generating sustainable agricultural production under various environmental stresses requires a detailed understanding of mechanisms that bacteria use to promote plant growth. In the present study, Pseudomonas aeruginosa (MW843625), a PGP soil bacterium with a minimum inhibitory concentration (MIC) of 150 mM against fluoride (F), was isolated from agricultural fields of Chhattisgarh, India, and was assessed for remedial and PGP potential. This study concentrated on biomass accumulation, nutrient absorption, and oxidative stress tolerance in plants involving antioxidative enzymes. By determining MDA accumulation and ROS (O₂•⁻ and H₂O₂) in Oryza sativa L. under F (50 ppm) stress, oxidative stress tolerance was assessed. The results showed that inoculation with P. aeruginosa enhanced the ability of O. sativa L. seedlings to absorb nutrients and increased the amounts of total chlorophyll (Chl), total soluble protein, and biomass. In contrast to plants cultivated under F-stress alone, those inoculated with P. aeruginosa along with F showed considerably reduced concentrations of F in their roots, shoots, and grains. The alleviation of deleterious effects of F-stress on plants owing to P. aeruginosa inoculation has been associated with improved activity/upregulation of antioxidative genes (SOD, CAT, and APX) in comparison to only F-subjected plants, which resulted in lower O₂•⁻, H₂O₂, and MDA content. Additionally, it has also been reflected from our study that P. aeruginosa has the potential to increase the activities of soil enzymes such as urease, phosphatase, dehydrogenase, nitrate reductase, and cellulase. Accordingly, the findings of the conducted study suggest that P. aeruginosa can be exploited not only as an ideal candidate for bioremediation but also for enhancing soil fertility and the promotion of growth and development of O. sativa L. under F contamination. Full article

The endophytic strain Amfr20 was isolated from roots of the olive tree var. Amfissa. Based on core-genome phylogenomic analyses, it was classified as Bacillus velezensis. The isolate showed positive results in numerous plant growth promoting traits, as well as in abiotic stress tolerance and in colonization related traits in vitro. Furthermore, the strain exhibited antifungal activity in vitro through diffusible and volatile compounds. Whole genome analysis revealed that the strain possesses large and various arsenals of secondary metabolite biosynthetic gene clusters involved in the bioagent’s functional properties, including plant growth promotion, colonization, and plant defense elicitation, as well as having the genomic potential for abiotic stress mediation. Based on TLC-bioautography, the ethyl acetate extracts of secreted agar-diffusible compounds from Amfr20 through single and dual cultures were found to be bioactive independently of the fungal pathogen’s interaction. The bacterial endophyte also proved efficient in suppressing the severity of anthracnose olive rot and gray mold post-harvest diseases on olive fruits and table grape berries, respectively. Lastly, Amfr20 beneficially affected Arabidopsis thaliana growth under normal and saline conditions, while boosting the plant development of Solanum lycopersicum through seed biopriming and root irrigation methods. The results of this multilevel study indicate that the novel endophyte Amfr20 Bacillus velezensis is a promising bioagent that should be exploited in the future as an ecological biopesticide and/or biostimulant. Full article

The growing demand for sustainable agriculture necessitates innovative strategies to enhance crop productivity while minimizing environmental impact. This study explores the biopriming potential of Cucumis sativus L. seeds using extracts derived from a consortium of nitrofixing cyanobacteria Nostoc commune, Calothrix sp., and Aphanothece minutissima subjected to static magnetic field (SMF) treatments. The cyanobacterial consortia were exposed to SMF at varying magnetic inductions (40–50 mT and 100–200 mT), followed by extract preparation and application as biopriming agents. Results demonstrated significant improvements in key seedling growth parameters, including root and stem length, vigor index I, and fresh biomass. The consortium treated with 40–50 mT SMF showed the most pronounced growth-stimulating activity, suggesting enhanced bioactive compound production under this treatment that might be related to auxin biosynthesis. Biopriming with cyanobacterial extracts maintained a balanced nutritional uptake and plant health, as indicated by stable fresh weight dry weight ratios. These findings highlight the potential of SMF-enhanced cyanobacterial consortia as biopriming agents for horticultural crops. Future research should elucidate the underlying modes of action and optimize conditions for broader crop applications. Full article

One of the main abiotic factors affecting agricultural productivity in semi-arid regions is salinity. Seed priming is a frequently used method to enhance plant growth under saline environments. The aim of this work was to demonstrate the differences in eight agronomical characteristics of two grass pea varieties under two salinity regimes (80 and 160 mM NaCl) when pre-exposed to seed priming (hydropriming, biopriming with Bacillus subtilis and their combination). The two varieties responded well to the priming treatments, with more beneficial effects monitored for the local variety. Evaluating the root characteristics that are most affected by stress, it was found that, at 80 mM NaCl, the combination of biopriming and hydropriming increased the fresh root weight by 36.8% and root length by 70% in the commercial variety, and by 124% and 47%, in the local variety, respectively. At 160 mM NaCl, biopriming increased the fresh root weight by 40.3% and root length by 50.3% in the commercial variety, while in the local variety, the combination of biopriming and hydropriming increased the fresh root weight by 124% and root length by 47%, respectively. Overall, biopriming and the combination of biopriming and hydropriming significantly enhanced plant growth characteristics of the two grass pea genotypes. Full article

The increase in extreme climate events associated with global warming is a great menace to crop productivity nowadays. In addition to abiotic stresses, warmer conditions favor the spread of infectious diseases affecting plant performance. Within this context, beneficial microbes constitute a sustainable alternative for the mitigation of the effects of climate change on plant growth and productivity. Used as biostimulants to improve plant growth, they also increase plant resistance to abiotic and biotic stresses through the generation of a primed status in the plant, leading to a better and faster response to stress. In this review, we have focused on the importance of a balanced redox status for the adequate performance of the plant and revisited the different antioxidant mechanisms supporting the biocontrol effect of beneficial microbes through the adjustment of the levels of reactive oxygen species (ROS). In addition, the different tools for the analysis of antioxidant responses and redox regulation have been evaluated. The importance of redox regulation in the activation of the immune responses through different mechanisms, such as transcriptional regulation, retrograde signaling, and post-translational modification of proteins, emerges as an important research goal for understanding the biocontrol activity of the beneficial microbes. Full article

Endophytic microbes in medicinal plants often possess beneficial traits for plant health. This study focuses on the bacterial endophyte strain B.L.Ns.14, isolated from Nigella sativa leaves, which demonstrated multiple plant growth-promoting properties. In vitro tests showed that B.L.Ns.14 supports plant growth, colonization, and tolerance to abiotic stress. The strain also exhibited antifungal activity against phytopathogens such as Rhizoctonia solani, Colletotrichum acutatum, Verticillium dahliae, and Fusarium oxysporum f. sp. radicis-lycopersici. Whole-genome analysis, supported by ANI and dDDH values, identified B.L.Ns.14 as Bacillus halotolerans. Genome mining revealed 128 active carbohydrate enzymes (Cazymes) related to endophytism and biocontrol functions, along with genes involved in phosphate solubilization, siderophore and IAA production, biofilm formation, and motility. Furthermore, genes for osmolyte metabolism, Na+/H+ antiporters, and stress response proteins were also identified. The genome harbors 12 secondary metabolite biosynthetic gene clusters, including those for surfactin, plipastatin mojavensin, rhizocticin A, and bacilysin, known for their antagonistic effects against fungi. Additionally, B.L.Ns.14 promoted Arabidopsis thaliana growth under both normal and saline conditions, and enhanced Solanum lycopersicum growth via seed biopriming and root irrigation. These findings suggest that Bacillus halotolerans B.L.Ns.14 holds potential as a biocontrol and plant productivity agent, warranting further field testing. Full article