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Background: Cauliflower (Brassica oleracea L.) and globe artichoke (Cynara scolymus L.) are vegetables with a high waste index mainly related to stems and leaves. In this study, enzymatic hydrolysates obtained from these wastes were proposed to be used as plant biostimulants. Life cycle assessment methodology was also applied to evaluate environmental performances related to cauliflower and artichoke byproducts. Results: Hydrolysates (HYs) were chemically and biologically characterized. Amino acids, organic acids, amines, polyols, mineral elements, phenols, tannins, flavonoids and sulfur compounds were identified and quantified by means of NMR, inductively coupled plasma mass spectrometry and UV–visible analyses. Cauliflower leaf and flower HYs showed the highest concentration of free amino acids, whereas stems showed the highest concentration of Ca. Regarding artichoke, asparagine, glutamine and aspartic acid were exclusively detected in stems, whereas artichoke leaves showed the highest Mg and Mn levels together with the highest antioxidant activity. The HYs diluted in water were tested as biostimulants. The impacts of five concentrations of HYs (0.00, 0.28, 0.84, 2.52 and 7.56 g L−1) on seed germination and early seedling growth of crimson clover, alfalfa, durum wheat and corn were investigated. Conclusions: The application of artichoke biostimulant (0.28 g L−1) positively influenced the coefficient of velocity of germination in alfalfa, crimson clover and durum wheat, whereas cauliflower biostimulant significantly improved corn germination speed. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The perennial species Hypericum perforatum, commonly known as St. John's Wort, is well regarded for its medicinal attributes, particularly its strong anti-inflammatory and antidepressant effects. Hypericum perforatum L., commonly known as balsam, is extensively employed in both traditional and contemporary medicine due to its biological properties, although the plant's medicine distribution is limited to Europe and Asia. This study pioneers the investigation of Hypericum perforatum cultivation in a Mediterranean country, specifically Greece, focusing on the effects of irrigation and biostimulants of two distinct genotypes on quantitative (height, drug yield, essential oil yield) and qualitative (essential oil content and composition) characteristics. A field trial was conducted at the experimental farm of the Agrotechnology Department at the University of Thessaly, located in the Larissa region. This study investigated various testing varieties under different irrigation levels and biostimulant applications. The results underscore the importance of customized irrigation and biostimulant strategies in improving yield and quality during the second growing season, establishing a foundation for sustainable agricultural progress. Notably, irrigated treatments significantly increased plant height, dry biomass yield, and essential oil production per hectare. Specifically, the essential oil yields for irrigated treatments were nearly double those of rainfed treatments, with 219 kg/ha for rainfed and 407 kg/ha for irrigated. The genotype played a crucial role in influencing production potential, height, flowering, and essential oil composition, with one variety demonstrating biennial blooming and modified essential oil compounds. While irrigation positively impacted yield, it also reduced certain essential oil compounds while increasing β-pinene content. The effects of biostimulants varied based on their composition, with some enhancing and others diminishing essential oil content. Notably, the biostimulant containing algae with auxin and cytokinin (B2) proved to be the most effective in improving the therapeutic profile. This study offers valuable insights into the cultivation of H. perforatum in a Mediterranean climate, highlighting the necessity for ongoing research into native populations, irrigation levels, biostimulants, fertilization, and other factors that affect crop yield and quality characteristics. [ABSTRACT FROM AUTHOR]

Rugulopteryx okamurae is an invasive brown macroalga that has recently proliferated in the western Mediterranean Sea, causing significant environmental challenges. This alga, however, contains valuable bioactive compounds—alginate, mannitol, and phlorotannins—that can serve as biofertilizers to promote plant growth and aid in bioremediation of degraded or contaminated soils. This study focused on optimizing the extraction of these compounds from R. okamurae, transforming an ecological issue into a beneficial resource. Algae samples collected from the Spanish Mediterranean coast were processed through a randomized factorial response surface design. Extraction conditions varied by time, temperature, algae-to-solvent ratio, and ethanol-to-water ratio to determine optimal yields. The highest yields achieved were 29.4, 11.9, and 0.35 g/100 g for alginate, mannitol, and phlorotannin's under extraction conditions of 6, 6, and 3 h; 58.8, 60.0, and 60.0 °C; and an algae:solvent ratio of 1:50, 2:45, and 1.40 g/mL, respectively. Characterization of the extracted sodium alginate using 1H-NMR, FTIR, and high-resolution electron microscopy confirmed its high purity and typical morphological features. This study highlights a sustainable approach to mitigating the invasive spread of R. okamurae while supporting soil health and sustainable agriculture. Harnessing this invasive species' biofertilizer potential provides a dual solution, aiding marine ecosystem conservation and developing eco-friendly agricultural practices. [ABSTRACT FROM AUTHOR]

Studies on selenium (Se) and silicon (Si) foliar biostimulation of different plants have been shown to affect concentrations of phenolic compounds. However, their effects on olive (Olea europaea L.) primary and secondary metabolites have not been fully investigated. Therefore, the effects of foliar sprayed Si and Se and their combination on the concentration of phenols, selected metabolites involved in the phenol biosynthesis, and mineral elements concentrations were determined in olive leaves of the field-grown cultivar Leccino. During the summer period, leaves were foliar sprayed three times, after which were sampled 30 days after the corresponding application. In general, foliar treatment of Si or Se increased the concentrations of several predominant phenolic compounds, such as oleuropein, oleacein, and specific flavonoids. The effects were especially pronounced after the third application in the harvest time sampling time. Amino acids and other phenol precursors were also significantly affected. The effects were phenol-specific and depended on the treatment, sampling time, and treatment × sampling time interaction. The response of verbascoside to the applied treatments appeared to be closely linked to corresponding changes in its amino acid precursors, such as tyrosine, while its connection with tryptophan and IAA has to be cautiously considered. In contrast, for other phenolic compounds like secoiridoids, a clear interdependence with their precursors was not identified, likely due to the more complex nature of their biosynthesis. The effects on the concentrations of elements other than Se and Si were milder. [ABSTRACT FROM AUTHOR]

Background: Avicennia marina ecosystems are critical for coastal protection, water quality enhancement, and biodiversity support. These unique ecosystems thrive in extreme saline conditions and host a diverse microbiome that significantly contributes to plant resilience and growth. Global food security is increasingly threatened by crop yield losses due to abiotic stresses, including saline soils. Traditional plant breeding for salt tolerance is both costly and time-consuming. This study explores the potential of bacteria from A. marina to enhance plant growth under saline conditions, emphasizing their ecological significance. Results: We analyzed the microbiome of A. marina from the Red Sea coast using high-throughput Illumina sequencing and culture-dependent methods across various compartments (bulk soil, rhizosphere, rhizoplane, roots, and leaves). Our findings revealed distinct compartment-specific microbial communities, with Proteobacteria being the dominant phylum. Functional predictions indicated diverse microbial roles in metal uptake and plant growth promotion (PGP). Remarkably, our culture-dependent methods allowed us to recover 56% of the bacterial diversity present in the microbiome, resulting in the isolation and characterization of 256 bacterial strains. These isolates were screened for PGP traits, including salt and heat tolerance, siderophore production, and pectinase activity. Out of the 77 bacterial isolates tested, 11 demonstrated a significant ability to enhance Arabidopsis growth under salt stress. Conclusions: Our study highlights the ecological significance of mangrove microbiomes and the potential of culture collections in offering innovative solutions for ecological restoration and crop production in saline conditions. The unique collection of mangrove bacteria, particularly from the rhizosphere and endophytes, showcases significant PGP traits and stress tolerance capabilities. These findings emphasize the importance of functional traits, such as salt tolerance, in the recruitment of endophytic bacteria by plants over taxonomic affiliation. The identified bacterial strains hold potential not only for developing biofertilizers to improve crop productivity but also for ecological restoration projects aimed at rehabilitating saline-degraded lands, thereby contributing to overall ecosystem health and sustainability. [ABSTRACT FROM AUTHOR]

Plant biologists have long used various model organisms, such as Arabidopsis thaliana, to study biological processes. The emergence of algal model organisms in recent years greatly facilitated plant research due to their compact genomes with a very low level of functional redundancy and their physiological properties. Here, the green microalga Chlorella vulgaris has been used as a model organism to study the effect of whey hydrolysates against heat stress in vascular plants. Cell density in culture, as well as chlorophyll and carotenoid concentrations, were monitored during an initial growth phase, followed by a heat stress phase and a subsequent recovery phase. Results showed that whey hydrolysates promoted the recovery of heat-stressed C. vulgaris and showed improved growth rates and generation times after heat stress compared to cells grown in BG-11 only. Similarly, the production of chlorophyll a, chlorophyll b, total chlorophyll and total carotenoids was improved in comparison to cells grown only in BG-11. The results may aid the development of novel biostimulants that protect crops from climate change due to higher throughput and shorter study times compared to traditional plant models. [ABSTRACT FROM AUTHOR]

The use of pesticides causes significant environmental problems, which drives the search for natural and non-toxic alternatives. In this study, a glycolipid biosurfactant (BS), produced by the yeast Starmerella bombicola ATCC 22214, was utilized as an active ingredient in natural agricultural defensive blends. The mixtures were tested for their fungicidal potential against phytopathogenic fungi isolated from fruits such as papaya, orange, and banana, demonstrating strong inhibition of fungal growth. The genera Penicillium, Colletotrichum, and Aspergillus were the pathogens present in the deterioration of the fruits used in the experiment. The biosurfactant was produced in a fermenter, yielding 10 g/L and reducing the surface tension to 31.56 mN/m, with a critical micelle concentration (CMC) of 366 mg/L. Blends of BS with oleic acid (T1) and lemongrass oil (T2) were found to be effective in controlling fungi. Additionally, the phytotoxicity of these formulations was assessed using Cucumis anguria (gherkin) seeds, where the blend of BS with castor oil (T4) showed the best performance, promoting seed germination. These results indicate the potential of such mixtures as natural alternatives for fungal control in plants and for application in sustainable agricultural systems. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a widely distributed mycotoxin and potent carcinogen produced by several fungal genera, but mainly by Aspergillus carbonarius. Grape contamination occurs in vineyards during the period between veraison and pre-harvest, and it is the main cause of OTA's presence in wine. The aim of the current study was the evaluation of 6 chemical and 11 biological plant protection products (PPPs) and biocontrol agents in commercial vineyards of the two important Greek white wine varieties cv. Malagousia and cv. Savatiano. The PPPs were applied in a 4-year vineyard study as single treatments or/and in combinations as part of IPM systems. Subsequently, nine strains of Aspergillus carbonarius were investigated for their sensitivity against seven active compounds of synthetic fungicides. During the multi-year field trials, various novel management systems, including consortia of biocontrol agents, were revealed to be effective against Aspergillus sour rot and OTA production. However, expected variability was observed in the experimental results, indicating the dynamic character of biological systems and highlighting the possible inconsistency of PPPs' efficacy in a changing environment. Furthermore, the IPM systems developed effectuated an optimized control of A. carbonarius, leading to 100% inhibition of OTA contamination, showing the importance of using both chemical and biological PPPs for disease management and prevention of fungal fungicide resistance. Finally, the majority of A. carbonarius tested strains were found to be sensitive against the pure active compounds used (fludioxonil, azoxystrobin, chlorothalonil, tebuconazole, cyprodinil, pyrimethanil and boscalid), with only a few exceptions of developed resistance towards boscalid. [ABSTRACT FROM AUTHOR]

Seaweed extracts are rich in diverse bioactive compounds that can stimulate growth and metabolism of plants. Thus, this study aimed to chemicallly characterize Laminaria japonica (LLE) and Ulva prolifera (ULE) liquid extracts, two formulated commercial products, and to assay their impact on seed germination and seedling development of common bean (Phaseolus vulgaris). Ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) identified 10 and 17 chemical compounds in liquid extracts of L. japonica and U. prolifera, respectively. Soaking common bean seeds with LLE or ULE increased the germination and seedling vigour. Both seaweed treatments also resulted in increased rooting, fresh weight, and length of roots and shoots in common bean seedlings. Soaking common bean seeds with LLE or ULE modified the carbohydrate, protein and amino acid content of common bean roots and shoots, as well as the α-amylase activity in roots. Sugars (mannitol and sucrose), organic acids (malic acid), and amino acids found in both seaweed extracts may exert effects on common bean seeds and seedlings, particularly on root development. Additionally, gibberellin, which is also found in ULE, could play a role in these effects. These results accurately describe the biochemical compounds present in two seaweed biostimulants and their effects on common bean seeds and plants. [ABSTRACT FROM AUTHOR]

The increased demand for sustainable and ecological agricultural tools to decrease the dependency on chemical fertilizers has surged throughout the last years. Cyanobacteria and microalgae-based biostimulants offer an innovative solution and ecofriendly platform for plant biostimulant production, due to their metabolic diversity and valuable value-added products. Focuses were directed especially towards marine and freshwaters microalgae whereas indigenous soil microalgae were rarely prospected for their biostimulant potential. The aim of this study was to assess the biostimulant activity of the soil microalga Chlorella vulgaris on seed germination performance. The effects of extraction method and plant choice on the biostimulant activity of C. vulgaris were investigated via the comparison of the composition and activity of four extraction techniques (aqueous extraction, acid hydrolysis extraction, organic solvent extraction, microwave-assisted aqueous extraction) on two different plant seed models (wheat and tomato). Seeds were soaked with four different concentrations (from 0.1 g L−1 to 2 g L−1) to determine dose-dependent effects. Results demonstrated significant differences in extracts biochemical composition and biostimulant effects on seed germination enhancement. Extract composition in terms of biomolecules concentrations revealed significant dissimilarities. Seed germination indices and biometric parameters were significantly improved by lower doses (0.1 g L−1 and 1 g L−1), while higher doses (2 g L−1) usually revealed negative effects. The best increases in wheat and tomato seed germination parameters were reached by using acid hydrolysis, aqueous and microwave-assisted aqueous extracts at lower doses. Thus, our results highlight that aqueous extract-based methods were as effective as other techniques. These findings shed light on the advantages of eco-extraction processes and microalgae-based aqueous extracts as eco-friendly biostimulants eligible for sustainable agriculture. [ABSTRACT FROM AUTHOR]

Biostimulants--including botanical extracts--are natural preparations that have no negative effects on environmental health or populations and improve soil health and plant growth. Our objective was to evaluate the use of botanical extracts from two native species of the Patagonian Monte, an infusion of Larrea nitida (5%-L5 and 10%-L10) and a ferment of Grindelia chiloensis (5%-G5 and 10%-G10), on soil properties and the growth of a model plant (Triticum aestivum). While the 5% and 10% Grindelia ferments increased microbial respiration, soil N and C content, and biomass production, the 10% Larrea infusion inhibited microbial respiration and decreased total biomass. The Grindelia ferment has potential for use as a biostimulant in agroecological production, whereas the Larrea infusion does not show potential for such use. The inhibitory effect of phenolic compounds on microbial activity and plant growth should be addressed in future studies. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the effects of individual and combined application of protein hydrolysate (PH) and humic-like substances (HLS) along with the reduction of fertilizer on the growth, physiological and biochemical parameters and mineral nutrition of tea nursery plants. Individual and combined effects of biostimulants were evaluated in a randomized complete block factorial experimental design with three replications. The experiment consisted of three levels of fertilizer (100%, 75% and 50%) and four biostimulant treatments (Control, PH, HLS and PH + HLS). Combined (PH + HLS) and individual application of biostimulants increased the leaf count and number of active buds by 44.8% and 52.3% respectively, compared to untreated plants. PH and combined treatments produced significantly higher and comparable total plant biomass under 75% and 100% fertilizer levels compared to control + 100% fertilizer. Positive effect exerted by HLS alone on total plant biomass was comparatively lower than PH and PH + HLS while significantly higher than control. PH application significantly increased the net photosynthetic rate (+ 30%), stomatal conductance (+ 48%) and concentration of CO2 in intracellular space (+ 36%) compared to control plants. All the biostimulant treatments positively affect the chlorophyll, total soluble sugars and proline contents in tea leaves, where higher values were recorded in PH treatment. Leaf N concentration was significantly increased by individual application of PH and HLS, while leaf P concentration was enhanced by PH and combined treatments. Leaf K, Mg and Ca concentrations were not influenced by biostimulant treatments. PH and combined treatments produced higher and similar effects on the growth of tea nursery plants with 75% and 100% fertilizer levels while HLS alone showed comparatively lower positive effects. It can be concluded that foliar application of PH alone or combining PH with HLS enhanced the growth performance of tea nursery plants along with a saving of chemical fertilizer by 25%. [ABSTRACT FROM AUTHOR]

Biostimulants such as seaweed extracts are emerging as crop management products that can enhance crop productivity and nutritional quality under abiotic stress conditions. Therefore, this study aimed to assess the effectiveness of a seaweed-derived biostimulant (Kelpak®) in alleviating salinity stress in spinach. A greenhouse experiment which consisted of five treatments (T1 = Control plants (no NaCl or seaweed extract (SWE), T2 = plants subjected to 300 mM NaCl without SWE, T3 = 300 mM NaCl + 1% dilution of SWE, T4 = 300 mM NaCl + 2.5% dilution of SWE, and T5 = 300 mM NaCl + 5% dilution of SWE) was conducted. The results showed that salinity without the addition of SWE reduced crop growth, relative water content, chlorophyll, and nutritional quality. Similarly, salinity induced severe oxidative stress, indicated by excessive amounts of superoxide radicals, malondialdehyde and the upregulation of catalase, peroxidase, polyphenols, and flavonoids. Interestingly, plants treated with 5% SWE displayed a substantial enhancement in crop performance, reduction in oxidative stress, and improved nutritional quality, characterised by considerable amounts of minerals, proximate constituents, and vitamins. These results support the use of seaweed extract (Kelpak®) as a biostimulant in enhancing growth and nutritional quality of spinach under saline cultivation. [ABSTRACT FROM AUTHOR]

The study of the application of biostimulants in agriculture aims to increase production and improve the efficient use of physical space and agricultural inputs, thus contributing to the sustainability of production systems. One of the new challenges is to verify the effects of joint application of these products to identify possible interactions during crop development. In this context, the present study aimed to evaluate the biostimulant potential of the isolated and combined use of nicotinamide and Azospirillum brasilense in developing cantaloupe melon plants and fruits. The treatments consisted of foliar application (combined and isolated) of nicotinamide (300 mg L−1) and A. brasilense (2 mL L−1). The results revealed that applying biostimulants positively influences gas exchange and vegetative growth of plants, especially in the root system. However, although the isolated application of each biostimulant resulted in greater effectiveness in terms of transpiration, stomatal conductance, and net CO2 assimilation, which provided an increase in the soluble solids content, the combined application of the two biostimulants resulted in significant gains in the growth of vegetative organs and fruits. Furthermore, combined applications of nicotinamide plus A. brasilense favored the development of biometric characteristics and fruit fresh weight, while isolated applications increased soluble solids content. [ABSTRACT FROM AUTHOR]

Plants have developed many defensive mechanisms to maintain their metabolism and growth under stress that, albeit inadequate with increased soil salinization rates and climate change, deliberately affect plant growth, productivity, and quality. As an alternative, yet effective, economical, and sustainable choice of environmentally benign source, seaweeds are proving to be potential replacements for conventional plant protectants and biostimulants. Seaweed extracts from various families have known to exert ameliorating effect in plants affected by salt stress as a cumulative action of sequential bio array of compounds under diverse categories such as phytohormones (Auxin, cytokinin, and Gibberilic acid), polyamines (putrescine and spermidine), phenolics (Vanillic and gallic acid), protein (Taurine, phosphoserine), carbohydrates (Trehalose, sorbitol, and mannitol) and betaines (glycine and proline beatine, and glycine, aminobutyric acid). These compounds are sought to promote the production and accretion of ameliorative compounds such as osmolytes that activates the MAPK pathway, triggering various signal cascades activating several genes and miRNAs that promote Na+ compartmentalization, Cl− efflux, increase cytosolic Ca+, ion homeostasis, cell–organ integrity. An increased rate of antioxidant enzymes (peroxidase, superoxide dismutase, and ascorbate peroxidase) in rapidly scavenging reactive oxygen species is also observed. Consequently, there is an increase in chlorophyll activities promoting sugar allocation, water, and resource utilization efficiencies, thereby protecting and promoting plant growth and productivity in an eco-friendly yet effective manner. [ABSTRACT FROM AUTHOR]

The effects of sheep wool (SW) and its hydrolysate (H) on the vegetative growth, root development, nutrient concentrations and sugar quality parameters of sugar beet grown under full (FF) and reduced fertilizer (RF) conditions were investigated. The treatments were as follows: FF, FF + SW (4 g kg−1) and FF + SW + H (4 g kg−1 + 4 ml kg−1), RF, RF + SW (4 g kg−1) and RF + SW + H (4 g kg−1 + 4 ml kg−1). The shoot and root samples were collected at two-week intervals from the beginning of root development to harvest. In these samples, temporal change of leaf mineral element concentrations and sugar quality parameters of the sugar beet roots were determined. Reduced fertilizer application did not have a negative effect on shoot and root growth. SW and SW + H treatments significantly increased total shoot (40.2 and 52.1%) and root yield (4.59 and 7.61%) of sugar beet in reduced fertilizer conditions. Nitrogen (N), calcium (Ca) and magnesium (Mg) concentrations of shoots increased significantly with SW and SW + H applications. Similar increases were also observed for phosphorus (P) in the 3rd sampling period. The treatments did not have an effect on potassium (K) concentrations of shoots but some increases observed in Na and α-amino N concentrations depending on SW and SW + H treatments. The SW and SW + H treatments significantly reduced sugar existence and refined sugar existence. On the other hand, the treatments had no significant effect on the refined sugar at harvest periods. Sheep wool and H can be incorporated into organomineral fertilizers, potentially reducing excessive fertilizer use and improving fertilizer efficiency. [ABSTRACT FROM AUTHOR]

Background: The incorporation of circular economy into agricultural processes is necessary to improve the efficiency of agronomic practices in the future. The biomass of macroalgae as well as humic substances is sustainable options for stimulating the efficient use of nutrients in plants. This study aimed to evaluate the modes of action of a potential plant biostimulant composed of an aqueous extract of Kappaphycus alvarezii seaweed plus fulvic acid (KAF) applied to rice (Oryza sativa L.) leaves. The aqueous extract was obtained from the fresh biomass of the macroalga Kappaphycus alvarezii and the fulvic acid was extracted from a cattle manure vermicompost (FAVC). Both fractions (KAlv-sap and FAVC) were characterized using 1H NMR. The bioactivity of KAF was evaluated in experiments with four treatments: control (foliar application of water), FAVC (foliar application of FAVC), KAlv-sap (foliar application of seaweed extract), and KAF (foliar application of FA + KAlv-sap). In rice, the expression of genes related to K+ and N transport, plasma membrane H+-ATPases, and oxidative stress defense enzymes were evaluated. Metabolites and N, K, and P contents, as well as photosynthetic efficiency and root morphology, were quantified. Results: The 1H-NMR spectra showed that KAF is rich in organic fragments such as sugars, nitrogenous, aromatic, and aliphatic compounds in general. Foliar application of KAF resulted in a 7.1% and 19.04% increase in the dry mass of roots and leaves, respectively. These plants had 19% more roots and 11% more total root length. The application of KAF increased in the plant sheaths the N and K contents by up to 50% and 14%, respectively. Conclusions: The mechanism of action by which KAF triggered these changes seemed to start with an improvement in the photosynthetic efficiency of plants and regulation through increased expression and suppression of genes related to K+, N, H+-ATPase transporters, and oxidative metabolism. KAF might become a sustainable plant biostimulant that promotes plant growth, development, and defense against abiotic stresses. [ABSTRACT FROM AUTHOR]

Introduction: Phosphorus recovery from waste streams is a global concern due to open nutrient cycles. However, the reliability and efficiency of recycled P fertilizers are often low. Biostimulants (BS), as a potential enhancer of P availability in soil, could help to overcome current barriers using recycled P fertilizers. For this, a deeper understanding of the influence of BSs on soil P turnover and the interaction of BSs with plants is needed. Methods: We conducted an incubation and a pot trial with maize in which we testednon-microbial (humic acids and plant extracts) and microbial BSs (microbial consortia) in combination with two recycled fertilizers for their impact on soil P turnover, plant available P, and plant growth. Results and discussion: BSs could not stimulate P turnover processes (phosphatase activity, microbial biomass P) and had a minor impact on calcium acetate-lactate extractable P (CAL-P) in the incubation trial. Even though stimulation of microbial P turnover by the microbial consortium and humic acids in combination with the sewage sludge ash could be identified in the plant trial with maize, this was not reflected in the plant performance and soil P turnover processes. Concerning the recycled P fertilizers, the CAL-P content in soil was not a reliable predictor of plant performance with both products resulting in competitive plant growth and P uptake. While this study questions the reliability of BSs, it also highlights the necessity toimprove our understanding and distinguish the mechanisms of P mobilization in soil and the stimulation of plant P acquisition to optimize future usage. [ABSTRACT FROM AUTHOR]

The agricultural use of synthetic pesticides, fertilizers, and growth regulators may represent a serious public health and environmental problem worldwide. All this has prompted the exploration of alternative chemical compounds, leading to exploring the potential of chitosan and PGPB in agricultural systems as a potential biotechnological solution to establish novel agricultural production practices that not only result in fewer adverse impacts on health and the environment but also improve the resilience and growth of the plants. In this work, an analysis of the impact of plant growth-promoting bacteria (PGPB) and chitosan on plant growth and protection has been conducted, emphasizing the crucial bioactivities of the resistance of the plants to both biotic and abiotic stressors. These include inducing phytohormone production, mobilization of insoluble soil nutrients, biological nitrogen fixation, ethylene level regulation, controlling soil phytopathogens, etc. Moreover, some relevant aspects of chitin and chitosan are discussed, including their chemical structures, sources, and how their physical properties are related to beneficial effects on agricultural applications and mechanisms of action. The effects of PGPB and chitosan on photosynthesis, germination, root development, and protection against plant diseases have been compared, emphasizing the intriguing similarities and synergistic effects observed in some of these aspects. Although currently there are limited studies focused on the combined application of PGPB and chitosan, it would be important to consider the similarities highlighted in this work, and those that may emerge in future studies or through well-designed investigations, because these could permit advancing towards a greater knowledge of these systems and to obtain better formulations by combining these bioproducts, especially for use in the new contexts of sustainable agriculture. Thus, it seems feasible to augur a promising near future for these combinations, considering the wide range of possibilities offered by chitinous biomaterials for the development of innovative formulations, as well as allowing different application methods. Likewise, the studies related to the PGPB effects on plant growth appear to be expanding due to ongoing research to test on plants the impacts of microorganisms derived from different environments, whether known or recently discovered, making it a very exciting field of research. [ABSTRACT FROM AUTHOR]

Humic acid (HA) is widely used in agriculture as a biostimulant to enhance plant growth and nutrient uptake. Studies on the early growth promotion of agarwood seedlings using plant biostimulants have not been explored. Therefore, the objective of this study was to extract and characterize peat-derived HA and to determine the optimum rate that would exert biostimulant action on the early growth of agarwood seedlings at the nursery stage. HA was extracted from peat soil using a modified rapid alkaline hydrolysis method. Produced peat humic acid (PHA) was compared with commercial humic acid (CHA) for its chemical and spectroscopic characteristics. One-month-old agarwood seedlings were treated with PHA at different rates (0, 20, 40, 80, 160 and 320 mg kg−1) before the commencement of the experiment. The study was conducted for four months. The C/N ratio of both PHA and CHA were 25.85 and 26.93, respectively. Scanning electron microscope (SEM) and fourier-transform infrared spectroscopy (FTIR) spectra observation reveals that PHA and CHA have similar surface morphology and functional groups respectively. Results revealed that agarwood seedlings treated with 80 mg kg−1 of PHA significantly increased the plant height, stem diameter, the number of leaves, leaf area, dry matter weight, N and P concentrations in plant tissues, and N, P and K uptakes. Based on the findings, incorporation of PHA at the rate of 80 mg kg−1 with planting medium could be used as an optimum rate to enhance the growth of agarwood seedlings in the nursery stage. [ABSTRACT FROM AUTHOR]

Biostimulants include a wide array of microorganisms and substances that can exert beneficial effects on plant development and growth, often enhancing nutrient uptake and improving tolerance against abiotic and biotic stress. Depending on their composition and time of application, these products can influence plant physiology directly as growth regulators or indirectly through environmental condition changes in the rhizosphere, such as nutrient and water availability. This review evaluated 48 case studies from 39 papers to summarize the effects of biostimulant application on fruit and tuber yields and on the quality of processing tomato and potato in open field conditions. For potato, PGPR bacteria were the main studied biostimulant, whereas the low number of studies on processing tomato did not permit us to delineate a trend. The yield and quality were greatly influenced by cultivars and biostimulant composition, application method, period, and dose. For processing tomato, a positive effect of the biostimulant application on the marketable yield was reported in 79% of the case studies, whereas for potato, the effect was reported in only 47%. Few studies, on processing tomato and potato, also reported data for quality parameters with contrasting results. The variability of crop response to biostimulant application in open field conditions highlights the need for more comprehensive studies. Such studies should focus on diverse cultivars, deeply understand the interaction of biostimulant application with agronomic management (e.g., irrigation and fertilization), and evaluate yield and quality parameters. This approach is crucial to fully understand the potential and limitations of biostimulant applications in agriculture, particularly regarding their role in sustainable crop production. [ABSTRACT FROM AUTHOR]

This study investigated the combined effects of novel plant growth-promoting rhizobacteria (PGPR)—Agrobacterium pusense NC2, Kosakonia oryzae WN104, and Phytobacter sp. WL65—and Ascophyllum nodosum seaweed extract (ANE) as biostimulants (PGPR-ANE) on rice growth, yield, and rhizosphere bacterial communities using the RD79 cultivar. The biostimulants significantly enhanced plant growth, shoot and root length, and seedling vigour; however, seed germination was not affected. In pot experiments, biostimulant application significantly increased the richness and evenness of bacterial communities in the rhizosphere, resulting in improvements in rice growth and yield, with increases in plant height (9.6–17.7%), panicle length (14.3–17.9%), and seeds per panicle (48.0–53.0%). Notably, biostimulant treatments also increased post-harvest soil nutrient levels, with nitrogen increasing by 7.7–19.2%, phosphorus by 43.4–161.4%, and potassium by 16.9–70.4% compared to the control. Principal coordinate analysis revealed distinct differences in bacterial composition between the tillering and harvesting stages, as well as between biostimulant treatments and the control. Beneficial bacterial families, including Xanthobacteraceae, Beijerinckiaceae, Acetobacteraceae, Acidobacteriaceae, and Hyphomicrobiaceae, increased in number from the tillering to harvesting stages, likely contributing to soil health improvements. Conversely, methanogenic bacterial families, such as Methanobacteriaceae and Methanosarcinaceae, decreased in number compared to the control. These findings highlight the dynamic responses of the rhizosphere microbiome to biostimulant treatments and underscore their potential benefits for promoting sustainable and productive agriculture. [ABSTRACT FROM AUTHOR]

Bassinosteroids (BRs) can induce plant defence responses and promote plant growth. In this work, we evaluated the effect of a natural (EP24) and a synthetic (BB16) brassinosteroid on strawberry (Fragaria vesca) plants exposed to saline stress. Treated plants showed higher shoot dry weight and root growth compared to untreated control plants. In BR-treated plants, crown diameters increased 66% and 40%, leaf area 148% and 112%, relative water content in leaves 84% and 61%, and SPAD values 24% and 26%, in response to BB16 and EP24, respectively. A marked stomatal closure, increased leaflet lignification, and a decrease in cortex thickness, root diameter and stele radius were also observed in treated plants. Treatments also reduces stress-induced damage, as plants showed a 34% decrease in malondialdehyde content and a lower proline content compared to control plants. A 22% and 15% increase in ascorbate peroxidase and total phenolic compound activities was observed in response to BB16, and a 24% increase in total flavonoid compound in response to both BRs, under stress conditions. These results allow us to propose the use of BRs as an environmentally safe crop management strategy to overcome salinity situations that severely affect crop yield. Climate change subjects crops to increasingly unfavourable environmental situations, such as soil salinity, which is very harmful to crops. The results of our work provide valuable information that could be useful for solve this problem. It was possible to verify the beneficial effect of brassinosteroids in strawberry (Fragaria vesca) plants exposed to saline stress, so we propose the use of these compounds as an environmentally safe crop management strategy to overcome situations of salinity that seriously reduce crop health and yields. [ABSTRACT FROM AUTHOR]

The influence of biostimulant treatments on Passiflora species was assessed by observing changes in the growth and leaf functional compounds of plants exposed to humic acids (HAs) and seaweed extracts (SEs) to determine their optimal application doses. Four different concentrations of HA irrigation (0, 144, 192, and 285 mg·L-1 per pot assigned as HI-1, 2, 3, and 4, respectively), HA spraying (0, 96, 128, and 192 mg·L-1 as HS-1, 2, 3, and 4, respectively), SE irrigation (SI-1~4 at 0, 1, 1.33, and 2 g·L21 per pot, respectively), and SE spraying (SS-1~4 at 0, 0.5, 0.67, and 1 g·L21, respectively) treatments were applied to 'Tainung No. 1' and Passiflora suberosa cultivars every week to study their responses in plant growth traits and metabolites. Results show that leaf dry weight (DW) and root DW of 'Tainung No. 1' plants under SS-3 and HI-4 treatments, respectively, were significantly increased compared with controls. Both HI-3 and HS-3 treatments remarkably increased vine length, fresh weight (FW), and DW of leaves and shoots in P. suberosa plants compared with controls. Furthermore, 'Tainung No. 1' and P. suberosa plants respectively subjected to HI-2 and SS-4 treatments contributed to developing biostimulant applications for obtaining higher total phenol and flavonoid content per plant. Both Passiflora species are recommended for treatment with SS-4 and SE to maximize orientin and isovitexin content, and for all their beneficial applications and sustainable use in agriculture. [ABSTRACT FROM AUTHOR]

Substances produced by plants have huge importance regulating multiple functions as germination, development promoter/ enhancer, yield increaser and activator of plant defense system against diseases and pests. Due to diversity, each plant species produces different compounds and in different concentrations. This research evaluated the role of 20 plants extracts obtained from different plant species or plant tissues on seed germination and seedlings establishment of maize and lettuce, in concentration of 5%, 10% or 20%. For this, two experiments were carried out, the first analyzing 20 plant extracts and the effects on germination percentage and root and shoot length based on the germination test for the two species. The second was carried out in a greenhouse, in a completely randomized design with three and ten repetitions for maize and lettuce, respectively, using only the three extracts with the best results from the first experiment. Seedling height and seedling dry matter were evaluated. To germination test most of extracts showed negative or no effects in both species. Only Conyza bonariensis at 5% and Richardia brasiliensis at 5% and 20% had positive effects on early seedling growth, increasing the seedlings length for maize seedlings. To seedlings establishment, Conyza bonariensis, Leucaena leucocephala and Richardia brasiliensis extracts did not show statistical difference to shoots height but increased the dry mass of shoots and roots. The results demonstrated that these plants extract have potential as growth promoters and can be a good option to a better seedling growth and establishment, collaborating to a more effective agriculture. [ABSTRACT FROM AUTHOR]

Biostimulants contribute to the physiological growth of plants by enhancing the quality characteristics of fruit without harming the environment. In addition, biostimulants applied to plants strengthen nutritional efficiency, abiotic stress tolerance, and fruit biochemical traits. We investigated the effectiveness of specific organic biostimulants. Five treatments were tested: (1) control (H2O, no biostimulants); (2) Magnablue + Keyplex 350 (Mgl + Kpl350); (3) Cropobiolife + Keyplex 120 (Cpl + Kpl120); (4) Keyplex 120 (Kpl120); and (5) Magnablue + Cropobiolife + Keyplex 120 (Mgl + Cpl + Kpl120) on the mineral uptake and physiology in black chokeberry (Aronia) plants, as well as the quality of their berries. The different treatments were applied to three-year-old chokeberry plants, and the experimental process in the field lasted from May to September 2022 until the harvest of ripe fruits. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) revealed that the fifth treatment significantly increased concentrations of P, Ca, and K. Additionally, the fifth treatment enhanced photochemical efficiency (Fv/Fm), water-splitting efficiency (Fv/Fo) in PSII, and the performance index (PI) of both PSI and PSII in chokeberry leaves. Improvements in photosynthesis, such as CO2 assimilation (A), transpiration (E), and water-use efficiency (A/E), were also noted under biostimulant applications. Upon harvesting the ripe fruits, part of them was placed at room temperature at 25 °C, while the rest were stored at 4 °C, RH 90% for 7 days. The cultivation with biostimulants had beneficial effects on the maintenance of flesh consistency, ascorbic acid concentration, and weight of berries at 4 and 25 °C, especially in the 5th treatment. Moreover, the total antioxidant capacity, anthocyanin concentration, and total phenols of the berries were notably higher in the third and fifth treatments compared to the control. These data suggest that selecting appropriate biostimulants can enhance plant yield and fruit quality by potentially activating secondary metabolite pathways. [ABSTRACT FROM AUTHOR]

Background/Objectives: The biostimulant SuperFifty, produced from the brown algae Ascophyllum nodosum, can improve crop quality and yield and mitigate stress tolerance in model and crop plants such as Arabidopsis thaliana, pepper, and tomato. However, the effect of SuperFifty on raspberries and strawberries has not been well studied, especially in terms of nutritional properties and yield. The aim of this study was to investigate the effect of SuperFifty on the quality and quantity of raspberry and strawberry fruits, with a focus on metabolic composition and essential elements, which together determine the nutritional properties and total yield of these two crops. Methods: Metabolome analysis was performed by liquid chromatography–mass spectrometry analysis (LC-MS), and essential elements analysis was performed by inductively coupled plasma-mass spectrometry (ICP-MS). Results: Here, we demonstrate that SuperFifty increases the fruit size of both raspberries and strawberries and enhances the yield in these two berry crops by 42.1% (raspberry) and 33.9% (strawberry) while preserving the nutritional properties of the fruits. Metabolome analysis of 100 metabolites revealed that antioxidants, essential amino acids, organic acids, sugars, and vitamins, such as glutathione, alanine, asparagine, histidine, threonine, serine, tryptophan, sucrose, citric acid, pantothenic acid (vitamin B5), as well as other primary metabolites, remain the same in the SuperFifty-primed fruits. Secondary metabolites, such as caffeic acid, p-coumaric acid, kaempferol, and quercetin, also maintained their levels in the SuperFifty-primed fruits. Analysis of essential elements demonstrated that elements important for human health, such as Zn, Mn, Fe, B, Cu, K, and Ca, maintain the same levels in the raspberry and strawberry fruits obtained from the biostimulant-primed plants. Magnesium, an important element known as a co-factor in many enzymatic reactions related to both plant physiology and human health, increased in both raspberry and strawberry fruits primed with SuperFifty. Finally, we discuss the potential financial and health benefits of the SuperFifty-induced priming for both growers and consumers. Conclusions: We demonstrate that SuperFifty significantly enhances the yield of both raspberries and strawberries, improves the marketable grade of the fruits (larger and heavier fruits), and enhances the nutritional properties by elevating Mg content in the fruits. Altogether, this biostimulant-induced molecular priming offers an environmentally friendly, efficient, and sustainable way to enhance the yield and quality of berry crops, with clear benefits to both berry producers and customers. [ABSTRACT FROM AUTHOR]

Abstract Background Avicennia marina ecosystems are critical for coastal protection, water quality enhancement, and biodiversity support. These unique ecosystems thrive in extreme saline conditions and host a diverse microbiome that significantly contributes to plant resilience and growth. Global food security is increasingly threatened by crop yield losses due to abiotic stresses, including saline soils. Traditional plant breeding for salt tolerance is both costly and time-consuming. This study explores the potential of bacteria from A. marina to enhance plant growth under saline conditions, emphasizing their ecological significance. Results We analyzed the microbiome of A. marina from the Red Sea coast using high-throughput Illumina sequencing and culture-dependent methods across various compartments (bulk soil, rhizosphere, rhizoplane, roots, and leaves). Our findings revealed distinct compartment-specific microbial communities, with Proteobacteria being the dominant phylum. Functional predictions indicated diverse microbial roles in metal uptake and plant growth promotion (PGP). Remarkably, our culture-dependent methods allowed us to recover 56% of the bacterial diversity present in the microbiome, resulting in the isolation and characterization of 256 bacterial strains. These isolates were screened for PGP traits, including salt and heat tolerance, siderophore production, and pectinase activity. Out of the 77 bacterial isolates tested, 11 demonstrated a significant ability to enhance Arabidopsis growth under salt stress. Conclusions Our study highlights the ecological significance of mangrove microbiomes and the potential of culture collections in offering innovative solutions for ecological restoration and crop production in saline conditions. The unique collection of mangrove bacteria, particularly from the rhizosphere and endophytes, showcases significant PGP traits and stress tolerance capabilities. These findings emphasize the importance of functional traits, such as salt tolerance, in the recruitment of endophytic bacteria by plants over taxonomic affiliation. The identified bacterial strains hold potential not only for developing biofertilizers to improve crop productivity but also for ecological restoration projects aimed at rehabilitating saline-degraded lands, thereby contributing to overall ecosystem health and sustainability.

Relevance. It is necessary to search for methods for obtaining environmentally friendly products and reducing the pesticide load on agrobiocenoses. Biostimulants can influence the increase in the yield of vegetable crops and improve their quality, which is confirmed by numerous studies. Stimulating effects depend on a combination of various biotic and abiotic factors. The aim of the study was to assess the effect of biostimulants on the yield and quality of Brassica Oleracea in the conditions of the Central Non-Chernozem zone on heavy loamy sod-podzolic soils.Methodology. A field experiment was carried out in the conditions of the Non-Chernozem zone of the Russian Federation on sod-podzolic soil in 2019-2021. In an experiment with two hybrids of Brassica Oleracea: F1 Zarnitsa (mid-early) and F1 Mechta (late-ripening), biostimulants Agrofil and MBK-BIS were studied for soaking seeds, seedlings and foliar treatment. The control variants were without fertilizer (absolute control) and the N90P120K150 background.Results. The effect of mineral fertilizers on both hybrids was characterized by an increase in the weight of heads of cabbage by 11.7 and 23.5%, respectively. When treating seeds, the weight of heads of cabbage increased by 15-18% compared to the background. Additional treatment with stimulants for soaking seedlings in Agrofil and foliar treatment with the MBK-BIS preparation increased the weight of heads of cabbage in comparison with the background in the F1 Zarnitsa hybrid by 21.4 and 23.3%, F1 Mechta - by 21.4 and 25.4%. The contribution of biostimulants to the yield of the used cabbage hybrids is more pronounced in the late-ripening hybrid, which directly depends on the amount of precipitation during the growing season. The studied biostimulants contribute to an increase in the content of vitamin C, fiber, and the amount of sugars in cabbage heads.Conclusion. Biostimulants MBK-BIS and Agrofil are effective for increasing the yield and improving the biochemical composition of the studied Brassica oleracea hybrids in the conditions of the Non-Chernozem zone of Russia.

Abstract Background The incorporation of circular economy into agricultural processes is necessary to improve the efficiency of agronomic practices in the future. The biomass of macroalgae as well as humic substances is sustainable options for stimulating the efficient use of nutrients in plants. This study aimed to evaluate the modes of action of a potential plant biostimulant composed of an aqueous extract of Kappaphycus alvarezii seaweed plus fulvic acid (KAF) applied to rice (Oryza sativa L.) leaves. The aqueous extract was obtained from the fresh biomass of the macroalga Kappaphycus alvarezii and the fulvic acid was extracted from a cattle manure vermicompost (FAVC). Both fractions (KAlv-sap and FAVC) were characterized using 1H NMR. The bioactivity of KAF was evaluated in experiments with four treatments: control (foliar application of water), FAVC (foliar application of FAVC), KAlv-sap (foliar application of seaweed extract), and KAF (foliar application of FA + KAlv-sap). In rice, the expression of genes related to K+ and N transport, plasma membrane H+-ATPases, and oxidative stress defense enzymes were evaluated. Metabolites and N, K, and P contents, as well as photosynthetic efficiency and root morphology, were quantified. Results The 1H-NMR spectra showed that KAF is rich in organic fragments such as sugars, nitrogenous, aromatic, and aliphatic compounds in general. Foliar application of KAF resulted in a 7.1% and 19.04% increase in the dry mass of roots and leaves, respectively. These plants had 19% more roots and 11% more total root length. The application of KAF increased in the plant sheaths the N and K contents by up to 50% and 14%, respectively. Conclusions The mechanism of action by which KAF triggered these changes seemed to start with an improvement in the photosynthetic efficiency of plants and regulation through increased expression and suppression of genes related to K+, N, H+-ATPase transporters, and oxidative metabolism. KAF might become a sustainable plant biostimulant that promotes plant growth, development, and defense against abiotic stresses. Graphical Abstract

A series of small-plot field trials were conducted between 2019 and 2021 with the spring barley variety Francin. The impact of Vital Root and YaraVita KOMBIPHOS on the grain quality of malting barley at varying nitrogen fertilization rates (50 kg·ha-1 N, 70 kg·ha-1 N, 90 kg·ha-1 N, and 110 kg·ha-1 N) was investigated. The following parameters were evaluated: grain size, thousand grain weight, specific weight, starch content, and protein content. The portion of grain

Global climate change has significantly reduced the yield of many crops due to various abiotic stressors. These stressors include water-related issues such as drought and flooding, thermal changes like extremely low and high temperatures, salinity, and adverse soil pH conditions including alkalinity and acidity. Biostimulants have emerged as promising and effective tools for mitigating the damage caused by these abiotic stressors in plants, ultimately enhancing both the quantity and quality of crops. Biostimulants are naturally derived substances that include humic acid, protein hydrolysates, nitrogenous compounds, seaweed extracts, beneficial bacteria, and molds. Even at low concentrations, biostimulants play a critical role in activating important plant enzymes, inducing antioxidant defenses, improving water relations and photosynthetic activity, stimulating hormone-like activities (particularly auxins, gibberellins, and cytokinins), and modulating root system development. This review discusses the physiological effects of microbial biostimulants on the quality and productivity of fruit crops, as well as their experimental applications.

The commercial value of kiwifruit is determined mostly by its nutritional composition and antioxidant content. The enrichment of these traits in an era where climate change affects kiwi growth conditions is worth investigating via the application of biostimulants that enhance plant growth. In this work, we evaluated the effects of three commercial biostimulants on the metabolism and growth characteristics of the Actinidia deliciosa cultivar ‘Hayward’: (I) a humic and fulvic-based biostimulant, (II) a glycine–betaine–proline-based biostimulant, and (III) a vegetal amino acid-based biostimulant. A biostimulant-free treatment was used as a control. In the two-year experiment (2022 and 2023), the growth characteristics of kiwi trees were measured, such as stem length, the number of leaves, leaf area, and fresh and dry biomass at the end of each growing season. The leaves’ total chlorophyll, total phenolics, and proline content were detected during the two seasons in order to obtain more insights into plant metabolism. Κiwifruit qualities and antioxidant traits, such as total soluble solids, titratable acidity, firmness, fresh and dry biomass, DPPH, and ascorbic acid (vitamin C), were recorded during the postharvest life for each season. Data analysis illustrated the beneficial impact of some biostimulants on several of the previously mentioned parameters, such as antioxidant kiwifruit traits, especially in the case of glycine–betaine–proline-based acid-based biostimulants.

Although chemical fertilization has gained a lot of attention due to its ability to increase the yield of fruit trees, it has been known to cause numerous environmental problems such as soil deterioration, alleviating beneficial microorganisms, and reducing fruit quality and safety. Hence, today, we aim to reduce these problems by using eco-friendly and sustainable biostimulants to promote nutritional status, yield, and quality. The effect of wood vinegar (WV) on mango production has yet to be investigated. Therefore, a field trial was conducted during the 2023 and 2024 seasons to evaluate the regulatory effect of individual and combined application of wood vinegar (WV), seaweed extract (SW), and humic acid (HA) on the performance of mango (Mangifera indica L.) cv. Ewais. The results revealed that all treatments had a pronounced effect and significantly improved the total chlorophyll content (107.7 and 106.6%), leaf N (2.02 and 2.23%), P (0.38 and 0.4), and K (1.07 and 1.13%), as well as enhancing the quality of mango fruits by increasing fruit length (11.68 and 12.38 cm), fruit width (7.8 and 8.59 cm), total sugars (40 and 37.3%), and TSS (21.9 and 20.8%) while reducing the total acidity (64.3 and 69.0%) in the 2023 and 2024 seasons, respectively, compared with the control. Based on this study, the treatment of 2 L/ha seaweed + 2 L/ha humic acid + 2 L/ha wood vinegar combined had the greatest effect on enhancing Ewais mango fruit yield by up-regulating leaf mineral acquisition, antioxidant response, and sugar accumulation. This study supports the application of HA and SW in combination with WV to improve mango fruit yield and quality. [ABSTRACT FROM AUTHOR]

The olive tree is well adapted to the Mediterranean climate, but how orchards based on intensive practices will respond to increasing drought is unknown. This study aimed to determine if the application of a commercial biostimulant improves olive tolerance to drought. Potted plants (cultivars Arbequina and Galega) were pre-treated with an extract of Ascophyllum nodosum (four applications, 200 mL of 0.50 g/L extract per plant), and were then well irrigated (100% field capacity) or exposed to water deficit (50% field capacity) for 69 days. Plant height, photosynthesis, water status, pigments, lipophilic compounds, and the expression of stress protective genes (OeDHN1—protective proteins' dehydrin; OePIP1.1—aquaporin; and OeHSP18.3—heat shock proteins) were analyzed. Water deficit negatively affected olive physiology, but the biostimulant mitigated these damages through the modulation of molecular and physiological processes according to the cultivar and irrigation. A. nodosum benefits were more expressive under water deficit, particularly in Galega, promoting height (increase of 15%) and photosynthesis (increase of 34%), modulating the stomatal aperture through the regulation of OePIP1.1 expression, and keeping OeDHN1 and OeHSP18.3 upregulated to strengthen stress protection. In both cultivars, biostimulant promoted carbohydrate accumulation and intrinsic water-use efficiency (iWUE). Under good irrigation, biostimulant increased energy availability and iWUE in Galega. These data highlight the potential of this biostimulant to improve olive performance, providing higher tolerance to overcome climate change scenarios. The use of this biostimulant can improve the establishment of younger olive trees in the field, strengthen the plant's capacity to withstand field stresses, and lead to higher growth and crop productivity. [ABSTRACT FROM AUTHOR]

Algae extracts may be a promising alternative to harmful chemicals and pesticides used commercially in the cultivation of plants with higher nutritional and health-promoting values. The cultivation of barley microgreens (Hordeum vulgare L.) was facilitated by the use of aqueous extracts from Fucus vesiculosus algae, which served as a biostimulant. Seeds for experiments were produced in accordance with EU standards, certified as organic and used to grow plants in a controlled pot experiment. A qualitative analysis of the extract, which was used to irrigate the plants, was also performed in this study, as well as stimulating properties by activating the system protecting against oxidative stress. Total phenolic content (TPC), total flavonoid content (TFV) and enzymes involved in their formation such as phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO), as well as enzymes involved in the removal of reactive oxygen species such as catalase (CAT) and superoxide dismutase (SOD), were determined in the obtained microgreen samples. Antioxidant activity against DPPH (2,2-diphenyl-1-picrylhydrazyl) was also evaluated. A noticeable increase in SOD content and antioxidant activity against DPPH was observed in barley microgreen samples after extract treatment. These results suggest that the use of extracts of this beneficial alga can enhance the antioxidant activity of the barley microgreens. [ABSTRACT FROM AUTHOR]

Microalgae are photosynthetic organisms that are described as an abundant source of numerous bio compounds of commercial value, and using this green treasure as a vital alternative to expensive synthetic hormones via biotechnological technique is the main objective of research. Murashige and Skoog medium supplemented with crude extract of Microcystis aeruginosa and Haematococcus pluvialis, separately was used to study its effect on Cynanchum acutum L., which is an important wild medicinal plant. Results revealed that all growth parameters have been affected where, the greatest shoot length (5.90 ± 0.45) has been reached with 4 mg/L of Microcystis aeruginosa extract, while the highest shoot number (7.50 ± 0.30) and leaf number (16.0 ± 0.59) were with 12 mg/L of Microcystis aeruginosa extract. Conversely, the maximum shoot length (12.5 ± 0.44) was reached with 2 mg/L of Haematococcus pluvialis extract, while the highest shoot number (6.00 ± 0.36) and leaf number per shootlet (22.0 ± 0.92) were with 5 mg/L of Haematococcus pluvialis extract. Biochemical analysis for algae and plant extracts conducted using HPLC proved the presence of phytohormones (zeatin, gibberellin, and kinetin) in algal extracts and nineteen important phenolic and flavonoid substances in plant extracts. The novelty of this study is to use algae as a natural source of growth regulators to achieve an economic benefit in addition to propagating Cynanchum acutum L. and increasing its important pharmaceutical products. [ABSTRACT FROM AUTHOR]

The chickpea (Cicer arietinum L.), often called the "poor man's meat", is a legume with remarkable nutritional value. Recently, its recognition as a functional food has grown, owing to its ability to improve human nutrition and reduce disease risk. This study explores the biofortification potential of black chickpea seeds through the targeted application of Bacillus subtilis, B. megaterium, and Rhizobium cicer. By inoculating the seeds, these rhizobacterial treatments aim to naturally enhance the bioactive compound profile by manipulating the plant root systems. The study comprehensively assesses key parameters including total antioxidant activity, protein content, total phenolic content, and macro- and micronutrient composition of bacterial inoculated black chickpeas grown under the ecological conditions of Bolu, Türkiye. Results showed that rhizobacterial inoculation significantly improved all measured traits compared to the control group. B. subtilis treatment increased total antioxidant activity by 10.6% and total phenolic content by 19.5%. Protein content exhibited by approximately 11% across all treatments. R. cicer treatment led to the most pronounced increases in macro- and micronutrients, particularly in calcium (38.5%), potassium (82.7%), magnesium (26.35%), phosphorus (15.23%), iron (155.3%), and zinc (44.21%). These results demonstrate that rhizobacterial treatments can significantly enhance black chickpeas' biochemical and nutritional quality. Thus, biofortified black chickpeas offer a promising, sustainable strategy for addressing global micronutrient deficiencies and combating hidden hunger, providing a valuable tool for improving food security. [ABSTRACT FROM AUTHOR]

The usage of biostimulants such as salicylic acid (SA) and NPK has emerged as an innovative practice for increasing crop production and quality. It plays a crucial role in the control of many physiological and metabolic processes. This experiment aimed to investigate the impact of SA and NPK treatment on the yield, growth, and quality characteristics of tomatoes grown in field conditions. The experiment structure laid out RCBD with three replications. Studied the effect of nine treatments of NPK (7 g/L), SA (0.05 mM, 0.1 mM, 0.5 mM, 1.0 mM), and combination of both (NPK+ 0.05 mM, NPK+ 0.1 mM, NPK+ 0.5 mM and NPK+ 1.0 mM) on two varieties of tomato. The foliar applications of SA, NPK, and their mixtures were administered during the planting phase, the onset of flowering, and the fruiting stage by maintaining intervals of 10 days after 15 days of transplanting. The response variables were yield (Plant height, number of fruits per plant, leaf area) fruit quality parameters (firmness, pericarp thickness, titratable acidity (TA), total soluble solids), nutraceutical quality parameters (Total sugars, ascorbic acid, non-reducing sugars, lycopene, β-carotene, reducing sugars, total phenols, and proline contents). The results indicate that foliar spray with SA and NPK boosts yield and phytochemical component production in tomato fruits compared to control. According to the findings, the treatments (NPK+ 0.5 mM and NPK+ 1.0 mM) showed the best results regarding bioactive compounds, yield, and quality parameters in both varieties of tomato under cold stress conditions. [ABSTRACT FROM AUTHOR]

The application of biological pesticides as alternatives to chemical phytosanitary products is a natural and innovative method to improve environmental protection and sustainable agricultural production. In this work, the compatibility between Trichoderma spp. and a commercial lignin extract was assessed in vitro and in vivo. The beneficial effects of lignin in combination with different Trichoderma consortia were evaluated in terms of improved growth and quantitative and qualitative tomato productivity. T. virens GV41 + T. asperellum + T. atroviride + lignin formulation was the most effective in growth promotion and increased root and stem dry weight compared to control (45.4 and 43.9%, respectively). This combination determined a 63% increase in tomato yield compared to the control, resulting in the best-performing treatment compared to each individual constituent. Consistent differences in terms of lycopene, GABA, ornithine, total, essential, and branched-chain amino acids were revealed in fruits from tomato plants treated with Trichoderma–lignin formulations (T. asperellum + T. virens GV41 + lignin) or with the microbial consortia (T. asperellum + T. virens GV41, T. atroviride + T. virens GV41). The developed bioformulations represent a sustainable biological strategy to increase yield and produce nutritional compound-enriched vegetables. [ABSTRACT FROM AUTHOR]

Salinization poses a significant challenge in agriculture, exacerbated by anthropogenic global warming. Biostimulants, derived from living microorganisms or natural extracts, have emerged as valuable tools for conventional and organic agriculture. However, our understanding of the molecular mechanisms underlying the effects of biostimulants is very limited, especially in crops under real cultivation conditions. In this study, we adopted an integrative approach to investigate the effectiveness of the combined application of plant growth‐promoting bacterium (Bacillus megaterium strain BM08) and a non‐microbial biostimulant under control conditions (normal watering) and salt stress. After confirming the yield increase under both conditions, we investigated the molecular mechanisms underlying the observed effect by measuring a number of physiological parameters (i.e., lipid peroxidation, antioxidants, chlorophylls, total phenolics and phytohormone content), as well as RNA sequencing and primary metabolite analyses. Our findings reveal that the combined effect of the microbial and non‐microbial biostimulants led to a decrease in the antioxidant response and an up‐regulation of genes involved in cytokinin biosynthesis under salt stress conditions. This, in turn, resulted in a higher concentration of the bioactive cytokinin, isopentenyladenosine, in roots and leaves and an increase in γ‐aminobutyric acid, a non‐proteic amino acid related to abiotic stress responses. In addition, we observed a decrease in malic acid, along with an abscisic acid (ABA)‐independent up‐regulation of SR‐kinases, a family of protein kinases associated with abiotic stress responses. Furthermore, we observed that the single application of the non‐microbial biostimulant triggers an ABA‐dependent response under salt stress; however, when combined with the microbial biostimulant, it potentiated the mechanisms triggered by the BM08 bacterial strain. This comprehensive investigation shows that the combination of two biostimulants is able to elicit a cytokinin‐dependent response that may explain the observed yield increase under salt stress conditions. [ABSTRACT FROM AUTHOR]

In Chile most of the walnut orchards are located in semiarid areas prone to saline conditions. Therefore, mitigating salinity stress is a relevant issue for farmers, especially for 'Chandler', the most sensitive planted variety. The aim of this study was to evaluate the effect of an extract of Ascophyllum nodosum (ANE; Acadian Organic®), applied through drip irrigation, on the vegetative and productive response of 'Chandler' walnut orchard affected by salinity (soil EC 1.8 dS m-1; irrigation water 2.0 dS m-1), effects on physical and biological soil properties. A dose of 4 L ha-1 ANE was applied monthly during two seasons (2021-2022 and 2022-2023) from the beginning of shoot growth until one month before harvest (24 L ha-1 per season), compared to unamended control. ANE applications promoted good conditions for tree development, greater shoot thickness, higher SPAD index measurements and better vegetative expression, represented by the NDVI spectral index. Consequently, a greater proportion of kernel filling and sizes was found in the ANE treatment (kernel size >32 mm, first season: 54% ANE vs 45% control; second season: 26% ANE vs 6% control). The stress mitigation of ANE promoted a positive cumulative effect after 1 season, with early vegetative development in the second season and significantly greater fruit size and yield efficiency. In addition, ANE application significantly improved physical and biological soil properties, possibly increased soil microbial activity, stimulated organic matter accumulation, improved the soil aggregate stability, and increased soil macroporosity at greater depths. The latter is relevant for salt management since a more stable soil porous system favors adequate water distribution in the soil profile under irrigation cycles, improving the displacement of salts and, consequently, reducing salinity stress. [ABSTRACT FROM AUTHOR]

As part of this research, an investigation was conducted to assess the impact of utilizing natural biostimulants on the biochemical and seedling characteristics of cowpea seeds variety VBN 4. Specifically, the study aimed to determine the most capable biostimulant in promoting enzyme activity and seedling vigor when applied at a 5% concentration for a period of eight hours. A total of eight different biostimulants were utilized in treating the seeds, and their outcomes were compared to those of untreated control seeds. The results revealed that humic acid at a 5% concentration and an eight-hour treatment period had the highest values for both enzyme activity and seedling vigor. Following closely behind were Pseudomonas fluorescens and brown kelp extract, showcasing their promising qualities as biostimulants. Overall, this study highlights the significant benefits that biostimulants offer to farmers as a means to increase seed viability and vigor. Based on these findings, it can be concluded that incorporating natural biostimulants into agricultural practices is a valuable strategy for improving crop yield and overall plant health. [ABSTRACT FROM AUTHOR]

Agriculture is facing challenges to produce more food in a climate scenario that works in the opposite direction. To amend this, agriculture has to invent new ways of making more with less. Interest in using by-products and finding new ways to utilize them has been increasing in recent years. The use of protein-rich sources for protein hydrolyzation and the use of these protein hydrolysates as biostimulants in plant production have been increasing. These mixtures are mainly produced by chemical and enzymatic hydrolysis from agro-industrial protein-rich by-products of animal, plant, and algal origins. The application of PHs has the potential to alleviate environmental stress; improve plant growth; and increase productivity, fruit yield, and abiotic-stress tolerance in agricultural crops. The use of these biostimulants offers a way to reduce the use of agrochemicals and agrees with the "do more with less" task in the future of agricultural production. This review gives an insight into the production of PHs, referring to sources of raw materials and methods of hydrolysis, the uptake and translocation of PHs, their effect on plant growth, the development and physiology, their role in alleviating stressful conditions, and their use in agriculture. The beneficial effects of PHs on different aspects of plant physiology, metabolism, and plant functioning under stressful conditions are evident. Inconveniently, crops, and sometimes even cultivars, are affected differently based on the way that PH is applied, the timing, and the concentration applied. Further research is needed to elucidate the mechanisms by which the components of PHs modify plant physiology and metabolism. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the influence of chosen biostimulants and microbiological preparations on the yield of sweet corn and the occurrence of Ostrinia nubilalis Hbn, and diseases. In both years of the study, the preparations used in this experiment did not have a statistically significant effect on marketable yield; however, in 2017, the highest weight was observed in the cobs of plants treated with Rizocore and Polyversum WP while the lowest in the cobs treated with RhizoVital 42. The biostimulant Asahi SL and the biological fungicide Serenade ASO proved to be the most effective in protecting sweet corn against cob and shoot infections by fungi of the genus Fusarium. All the preparations reduced the development of the common smut in corn, especially on the cobs. There were no statistically significant differences in cob infection by the O. nubilalis in the combinations treated with different preparations, although the lowest number of cobs damaged by pest in both years were observed on plots treated with Serenade ASO and RhizoVital 42, while the highest on plots treated with Goëmar BM. [ABSTRACT FROM AUTHOR]