Drought stress is one of the major abiotic factors limiting crop growth and yield, particularly in wheat. Water deficit leads to reduced chlorophyll content, impaired photosynthetic performance, and decreased biomass accumulation. Nitrogen fertilization may influence plant physiological responses to drought; however, its capacity to alleviate drought-induced growth reduction remains uncertain. A pot experiment was conducted to evaluate the impact of different nitrogen-based fertilizers on wheat seedlings grown under irrigation level 60% PPW (control) and 30% PPW (drought stress) conditions, with balanced levels of phosphorus and potassium maintained in all treatments. Water deficit led to substantial reductions in chlorophyll content compared to optimally irrigated plants. Similarly, the performance index (PI) decreased by 139.3% at Term 1 (1 day after foliar nitrogen application) and 27.2% at Term 2 (7 days after application). The net photosynthetic rate (Pn) declined markedly under drought conditions and was not significantly improved by nitrogen fertilization, indicating a partial and mainly short-term physiological response to nitrogen under water deficit. The application of nitrogen fertilizers, particularly urea and Nitron S, modulated the relative chlorophyll content and selected chlorophyll fluorescence (Fv/Fm, Fv/Fo, PI) and gas-exchange (E, gs, Ci) parameters under drought conditions, mainly shortly after application. However, aboveground dry biomass under drought conditions was not significantly affected by any nitrogen fertilizer. Urea induced the most consistent short-term physiological responses under both irrigation regimes, with effects more pronounced shortly after application, whereas Nitron S showed fertilizer-specific effects under drought stress. Overall, the results demonstrate that foliar nitrogen fertilization can modulate short-term physiological responses of wheat seedlings to drought but does not translate into sustained improvements in Pn or biomass accumulation. In the context of climate change and increasing water scarcity, identifying nitrogen fertilizers that support physiological functioning without overestimating growth benefits has critical implications for sustainable wheat production. Optimizing nitrogen fertilization may, therefore, contribute to improved nutrient management strategies under water-limited conditions.

ABSTRACT This study investigated the effects of pre-harvest foliar applications of Ca(NO3)2 and KNO3 on nutritional quality of Capsicum annuum, Capsicum chinense, and Capsicum frutescens in the late seasons of 2021 and 2024, and early seasons of 2023 and 2024 in Abeokuta, Nigeria. The experiment utilized four foliar fertilizer : Ca(NO3)2, KNO3, alternating Ca(NO3)2 with KNO3, and no fertilizer application in a two factorial Randomized Block Design. Data were analyzed using ANOVA, Principal Component Analysis, and k-means clustering. Species, fertilizer type, and their interaction significantly influenced pepper fruit nutrition. In Early Season 2024, Ca(NO3)2 increased N content in C. frutescens by 24.67%, while in Late Season 2024, it improved Fe content in C. chinense 3.27-fold compared to controls. KNO3 consistently enhanced K content and raised carotenoids in C. frutescens by 43.33%. Non-sprayed controls showed high secondary metabolites (phenolics) but lower macronutrients. In conclusion, C. frutescens exhibited superior nutritional quality in late seasons. Foliar sprays inconsistently influenced nutritional variables but proved effective in mitigating anti-nutrient accumulation. Consequently, species-specific and season-dependent fertilizer management is recommended to optimize pepper nutrient density and safety.

Abstract In recent years, the cultivation area and consumption of quinoa ( Chenopodium quinoa Willd) have increased in the country due to its nutritional properties and ability to grow in adverse conditions. Based on climate change scenarios, long periods of drought are expected, which emphasizes the need for planting and developing new plants that are adapted to these conditions. Quinoa's morphological, biochemical, and physiological responses to nanoparticle Fe and Zn foliar treatment during drought stress were examined. Quinoa development was also compared to zinc and iron. With nutrient supplementation, a 2019 drought experiment assessed quinoa growth and quality. The Giza1 cultivar of quinoa was evaluated for its morphological, biochemical, and physiological parameters. The experiment studied three factors: (1) Foliar application of different micronutrient combinations (control, Fe(as FeSO 4 ), Zn (as ZnSO 4 ), Fe+Zn, nano‐Fe, nano‐Zn, nano‐Fe+nano‐Zn); (2) Application timing at two reproductive stages (50% flowering and 100% flowering); and (3) Drought stress at two levels: control (irrigation at soil moisture potential of field capacity) and stress (irrigation at soil moisture potential of −9 bar). Drought stress greatly reduced plant height, main and lateral branch numbers, leaf number, inflorescence length, leaf, stem, and seed dry weight, wet and dry plant weights, and seed output. Foliar fertilizer increased plant height, main and lateral branch numbers, leaves, inflorescence length, stem, seed dry weights, and plant wet and dry weights. Iron and zinc nanoparticles were better nutrition. Drought stress affects quinoa production less with fertilizer. Also most metrics were negatively affected by drought stress; however, foliar nano‐Fe and nano‐Zn at 50% flowering minimized its negative effects. High protein, proline, soluble carbohydrates, water, photosynthetic pigments, antioxidant enzyme activity, and low malondialdehyde. Drought stress‐application time‐nutrient correlations were significant in most parameters. At50% blooming, nano‐Fe and nano‐Zn treatments had the highest protein, proline, soluble carbohydrate, and antioxidant enzyme levels under drought stress.

The continuous increase in the cost of water and fertilizers associated with increasing global demand for food driven by population growth and the growing concern on the current environmental impact of agriculture led us to the urgent search for more sustainable agronomic practices. Among these, the use of biostimulants has emerged as a promising strategy to enhance crop productivity and resource-use efficiency while reducing reliance on conventional inputs. Nevertheless, identifying the most suitable type of biostimulant, along with the optimal method, dosage, and timing of application, remains particularly critical for staple crops such as rice, being an area that requires further in-depth research. In the present experiment, two silicon-based biostimulant formulations were tested under controlled conditions at two different concentrations and applied at different key phenological stages in rice through foliar spraying. Agronomical components (plant height, tiller number, aerial dry weight, grain yield, and harvest index), whole plant physiological parameters (vegetation indices such as NGRDI, TGI, GA and GGA readings), leaf traits (photosynthetic and transpirative gas exchange, total nitrogen and carbon concentration and the stable isotopic composition, pigment content), and the grains characteristics (mineral composition (macronutrients and heavy metal concentrations) were evaluated. Among the tested products, the Simosa formulation was the most effective, significantly enhancing tiller number, aerial dry weight, grain yield, chlorophyll concentration and nitrogen balance index. Nevertheless, no consistent dose-dependent effects were observed. In contrast, Siliforce-4 did not demonstrate clear effects on either biomass accumulation or physiological traits. Regarding rice grain consumption, only copper concentrations exceeded the threshold established by EFSA, 2009. Overall, these results underscore the need for further studies to determine the most effective silicon foliar fertilizer formulations, as well as optimal dose and timing of application for boosting rice productivity.

Black orchids are a renowned germplasm source in East Kalimantan. However, their habitat is becoming increasingly scarce due to slow cultivation, necessitating rapid and precise propagation methods, such as tissue culture. Subculture is a key component of tissue culture. The purpose of this study was to determine the growth response of black orchid on MS growing media with the addition of foliar fertilizer and natural extracts. This research was conducted at the Tissue Culture Laboratory, Faculty of Mathematics and Natural Sciences, Mulawarman University. The study period was three months, from March to June 2025. This study used a non-factorial Completely Randomized Design (CRD). Three treatment levels, each level consisting of eight replications: S0 (control), S1 (MS Media + leaf fertilizer), S2 (MS Media + natural extract). Data were analyzed for diversity using Analysis of Variance (ANOVA) with an α level of 5% and then Duncan's Multiple Range Test (DMRT) with an α level of 5%. The results showed that all three treatments significantly affected all observed variables. The addition of leaf fertilizer to MS media produced the best response in terms of shoot emergence time and shoot number. The addition of natural extract to MS media produced the best response in terms of leaf number.

The article presents the results of field studies on the formation of productivity of maize hybrids depending on the mineral nutrition system and the application of foliar microfertilizers. The relevance of the research is determined by the need to improve the efficiency of nutrient use, ensure the realization of the genetic potential of modern maize hybrids, and meet the growing demand for grain as food, feed, and bioenergy raw material. The studies were conducted during 2022–2023 on the agricultural lands of the “Rybachenkove” farm located in the Haisyn district. The aim of the research was to determine the peculiarities of grain yield formation and the calculated bioethanol output of maize hybrids MAS 25F and MAS 24C depending on the type of nitrogen fertilizer, as well as the timing and frequency of foliar application of micronutrient fertilizers. The experimental design included the assessment of a fertilization background with N22P57K57 as a control and the same background supplemented with carbamide, combined with foliar application of the micronutrient fertilizer Wonder Leaf Mono Zn 8 at the phenological stages of 5–7 and/or 7–9 leaves. The results of the study showed that the combination of carbamide with foliar fertilization at the 5–7 leaf stage provided the highest grain yield, averaging 9.0 t/ha for both investigated hybrids, which exceeded the control by 1.7 t/ha or 23%. Foliar feeding at the 7–9 leaf stage resulted in a lower but stable yield increase of 10–15%, while double application ensured a yield increase of 14–19%. The maximum calculated bioethanol output, up to 3.5 t/ha, was obtained with foliar micronutrient application at the 5–7 leaf stage. Variance analysis revealed that fertilization was the dominant factor influencing productivity (43%), whereas the contribution of the hybrid factor accounted for 33%.

In 2021/2022 – 2022/2023, an experiment with two varieties of winter common wheat was conducted at the training and experimental field of the Department of Plant Production at the Technical University - Varna. During their spring vegetation, combined mineraland foliar fertilization were applied. Soil fertilization was carried out with ammonium nitrate with a fertilizer rate of 12 kg/da (active substance) in phase BBCH 23-29. Three fertilizer products were used for foliar fertilization. They were applied twice with a dose of 300 ml/da in phases BBCH 29-39 and BBCH 51-59. An unfertilized control was also included in the experiment for comparative analysis. The response of the studied varieties to the used foliar fertilizers is expressed by the obtained yields and the protein content in the grain. Foliar fertilization under favorable weather conditions increases the productivity and protein content in the grain of the varieties Marilyn and Nikodim. Under these conditions, the effect of the fertilization factor is large. Under unfavorable weather conditions, the share of the variety factor is significant. Under favorable conditions of the year the average yields obtained in the fertilizer variants compared to the unfertilized controls are higher, while for the protein content this dependence is observed in the year with unfavorable conditions. The Nikodim variety shows higher average grain yield values ​​in most fertilization variants, which suggests that this variety may be more reactive to different types of fertilization. The Marilyn variety shows lower variability in the results, which suggests greater resistance, albeit with lower average yields under some types of fertilization, but with higher protein content.

ABSTRACT Pomegranate (Punica granatum L.) fruit is highly valued for its rich phytochemical composition. The present study aims to evaluate the effects of different foliar fertiliser applications on the physicochemical characteristics, nutrient composition, phytochemical content, antioxidant capacity, and sensory attributes of the ‘Pınarbaşı’ pomegranate cultivar. Fruit weight varied between 239.65 and 276.40 g across treatments, while sensory evaluation scores ranged from 3.00 to 3.73. Potassium (K) concentration in the fruit showed a notable variation, ranging from 1098.71 to 2136.99 mg kg− 1. Biochemical analyses revealed substantial differences in total phenolic content (997.28–1398.18 mg GAE/100 g), total flavonoid content (417.22–444.81 mg QE/100 g), total anthocyanin content (5.99–11.98 mg C3gE L−1), and antioxidant activity (28.60–51.97%). Principal component analysis identified three principal components explaining 92.7% of the total variance. Heat map analysis revealed distinct clustering patterns among treatments, highlighting the specific effects of foliar fertilisers on nutrient distribution. Correlation matrix analysis further indicated statistically significant relationships between foliar fertiliser applications and fruit physicochemical properties, with a strong positive correlation observed between fruit weight and fruit length (r = 0.93, p < 0.05). Foliar fertiliser applications significantly improved fruit quality, nutrient composition, and antioxidant properties compared with the control. These findings underscore the potential of foliar fertilisation in enhancing pomegranate production.

The experiment was conducted in the period 2019-2022 in plum (Prunus domestica L.) cv. 'Stanley' plantation of the Institute of Agriculture – Kyustendil, Bulgaria. The orchard was established in 2013 with distances between trees of 5x5 m. The soil and foliar fertilizers were applied as follows: V 1 – unfertilized – (control), V 2 – Ecofol program, V 3 – Humustim, V 4 – Chicken manure Vita organic 2.5 kg/tree and V 5 – Chicken manure Vita organic 5.0 kg/tree. The influence of the fertilization treatments on the nitrogen, phosphorus and magnesium content of the plum leaves cv. 'Stanley' was non-statistically significant. The Vita organic chicken manure with a rate of 2.5 kg/tree increased the potassium content in the leaves by 15.3% above the control, and the rate of 5.0 kg/tree – by 21.0%, confirmed by the analysis, which showed statistically significant differences (P 0.001). The foliar treatment has been proven to increase the calcium content – Humustim – by 11.3% at P 0.001, and the application of the Ecofol program – by 14.3%. A positive correlation was established for the pairs nitrogen-yield – r = 0.576*, phosphorus-calcium – r = 0.564*, phosphorus-magnesium – r = 0.655* and calcium-magnesium – r = 0.683*.

Plasma-activated water as a solvent for foliar fertilizer: effects on the growth and biochemical properties of oregano (Origanum vulgare L.)

Current agriculture is caught between two major pressures: ensuring food security for a growing population and mitigating the negative effects of climate change and natural resource degradation. In this context, wheat occupies a strategic position, having a direct impact on both economic balance and social stability. At the same time, the vulnerability of this crop to abiotic (drought, high temperatures, salinity) and biotic (diseases, pests) stresses underlines the urgent need for innovative technological solutions.Stress factors, either abiotic or biotic, severely limit the performance of wheat crops and reduce both production and quality, with a direct impact on economic efficiency and food security. Under these conditions, the integration of complex technological solutions is no longer optional, but necessary. Organo-mineral fertilization, careful administration of foliar fertilizers, as well as the use of biostimulants and amino acids have demonstrated visible effects in increasing stress tolerance and increasing yield. They support metabolic processes, maintain physiological balance and contribute to better stability of grain quality.

IntroductionSelenium (Se) deficiency remains a significant global nutritional issue, emphasizing the need for efficient crop-based biofortification interventions.MethodsThis study examined the mechanistic responses of sweet maize (Zea mays L.) to foliar Se fertilization (0, 20, 40, and 60 g ha−1), focusing on antioxidant regulation, physiological traits, nutrient metabolism, Se speciation, and Se bioaccessibility.ResultsModerate Se doses (20–40 g ha−1) enhanced chlorophyll retention and photosynthetic efficiency, accompanied by increased activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), as well as 22.8% reduction in malondialdehyde (MDA), indicating improved redox homeostasis. These biochemical improvements facilitated higher assimilate accumulation, resulting in a 2–7% increase in fresh cob yield and enhanced levels of soluble sugars, amylose, protein, vitamin C, and key micronutrients (magnesium, iron, copper, manganese). However, excessive Se (60 g ha−1) caused oxidative imbalance, leading to decreased enzyme activity and reduced yield. Kernel Se concentration increased significantly with Se supply, dominated by selenomethionine (SeMet) (82.3% of total Se), exhibiting high in vitro bioaccessibility (35.6% gastric, 76.0% intestinal).DiscussionThe coordinated regulation of antioxidant defense and nutrient metabolism under optimal Se supply enhances both plant physiological performance and the nutritional bioefficacy of edible kernels, providing a mechanistic framework for sustainable Se biofortification.

There is a scarcity of information on the effects of fertilization combined with cover crops on the soil physicochemical properties in olive orchards. We assess the effects of fertilization, cover crop, and harvest time on various soil characteristics in an olive (Olea europaea) orchard. Studies were conducted during the growing seasons of 2021/2022 and 2022/2023 in southwestern Buenos Aires, Argentina. The general experimental design in 2021/2022 and 2022/2023 was split plots. Fertilization treatments included an organic manure applied to the soil, inorganic fertilization applied to the soil or leaves of olive trees, and an unfertilized control. Additionally, a mixture of Vicia benghalensis with Avena sativa was either planted or not (control) as a cover crop. The study demonstrated that soil pH increased on average from mid-spring to mid-autumn during both studied growing periods. Soil organic matter, available phosphorus (P), and extractable potassium (K) were greater at 0-20 cm than at 20-40 cm soil depth. In 2022/2023, the percentage of soil organic matter appeared to be higher in areas with a cover crop than in those without, from early summer to early winter. Soil concentrations of ammonium, nitrate, P, and K were either similar or most often higher never lower in soils with organic and inorganic fertilizations compared to the inorganic foliar fertilization. These three types of fertilization showed greater nutrient concentrations than the unfertilized control. Finally, soil available P concentrations appeared to be higher in areas without vegetation cover than in those with a cover crop at 0-20 cm soil depth.

Abstract The present study aimed to evaluate the effectiveness of a foliar fertilizer made from local inputs to strengthen crops and control pests and diseases in an ecological way. The research followed a quantitative, applied, and experimental design approach, using local crops as the unit of analysis. A foliar fertilizer was prepared from organic materials available in the area and applied using a randomized block design comparing a treatment group and a control group. Results showed that the foliar fertilizer contained a balanced composition of nitrogen, phosphorus, potassium, and essential micronutrients, increasing crop productivity and quality. A significant reduction in pest and disease incidence was also observed without adverse environmental effects. The study concludes that locally produced organic foliar fertilizers represent a viable and sustainable alternative to synthetic fertilizers, contributing to ecological and resilient agriculture in rural areas. Keywords: foliar fertilizer, local inputs, ecological agriculture, sustainability, biological control

Olive (Olea europaea L.) cultivars often exhibit genotype-specific responses to micronutrient management. In this study, we investigated the metabolic leaf fingerprinting of three cultivars ‘Rošinjola’, ‘Leccino’, and ‘Istarska bjelica’ at two sampling periods (SP-I = 64 days after treatment (DAT) and SP-II = 118 DAT), following boron foliar fertilisation (+B = 41.62 mM B; −B = 0 mM B) applied 50 days after anthesis. To our knowledge, this is the first study to provide such a detailed evaluation of boron-induced shifts in phenolic metabolism in olive leaves. At harvest (SP-II), all three cultivars showed higher concentrations of total identified phenolic compounds in +B plants compared with the −B controls. Notably, the concentration of verbascoside at harvest was higher in +B plants of ‘Istarska bjelica’ and ‘Leccino’, but not in ‘Rošinjola’. Oleuropein content increased in +B plants at harvest to a level higher than 4870 mg/100 g DW, irrespective of cultivar. Conversely, apigenin-7-glucoside declined from SP-I to SP-II in ‘Leccino’ regardless of treatment, whereas in ‘Istarska bjelica’, this decrease occurred only in control plants, with boron preventing the seasonal decline. These findings confirm the prolonged effect of boron foliar fertilisation on phenolic metabolism in olive leaves and highlight cultivar-specific differences in metabolic responses. Further research is needed to clarify how these metabolic shifts relate to primary plant metabolism and how they influence olive oil quality traits among cultivars grown under Croatian conditions.

The use of silicon (Si) in agriculture has increased due to improvements in growing conditions, induction of resistance to biotic and abiotic stresses, as promotion of gains in the production. In this context, this research evaluated the agronomic, physiological and root characteristics, as well as the differential profit of the soyabean as a function of nitrogen fertilization at planting and foliar Si fertilization. The experimental design was arranged in randomized blocks, in a 2x2x5 factorial scheme. The first factor was the growing seasons (2019/2020 and 2020/2021), the second factor was the presence or absence of nitrogen fertilization at planting (0-control and 20 kg ha−1 of N), and the third factor was foliar silicon fertilization (0-control, 150, 300, 450, and 600 g ha−1 of Si). The foliar application of Si significantly reduced of gas exchange, except for the internal CO2 concentration, when associated with N fertilization at planting. In the root system, the length, area and volume of soybean roots increased by 133%, 115% and 90% for the respective variables when 450 g ha−1 of Si was applied. Nitrogen fertilization at planting did not increase soybean grain yield. However, foliar fertilization containing 450 g ha−1 of Si achieved 5.543 kg ha−1 of grains, irrespective of the growing season and the presence of nitrogen fertilization at planting. This same dose provided the best root development of soybean plants and the maximum differential profit (US$ 332).

Hydrogen water, characterized by a high concentration of unionized hydrogen molecules, is being presented as a new alternative in agriculture. This study focused on the application of hydrogen water to leaves and its effects on crop yield and quality, especially on leaf lettuce, through foliar fertilization (twice a week at 25 L per 330 m2) experiments with hydrogen water with dissolved hydrogen of more than 300 ppb and control water with dissolved hydrogen close to 0 ppb. The experimental group that received foliar fertilization showed significant advantages over the control group in leaf thickness and stem thickness characteristics that affected post-harvest distribution quality. Area growth rate analysis revealed a consistently higher average area growth rate (up to 0.86%) in the group treated with hydrogen water compared to the control group (0.1%). The results of an independent-sample t-test of spectral indices showed that the experimental group showed a significance level above the critical value (p &lt; 0.05) compared to the control group in the analysis results of NDVI in soil cultivation and NDRE in hydroponic cultivation. Although other spectral indices did not show differences between the experimental and control groups at the significance level, the average of all samples was higher in the experimental group than in the control group. Overall, the findings suggest that foliar application of hydrogen water positively influences the growth of lettuce crops, as evidenced by comprehensive trait, area growth rate, and spectral index analyses. These results underscore the novelty of hydrogen water as an efficient foliar treatment that enhances crop performance with minimal system changes. Its potential to improve yield quality while reducing chemical input demands suggests clear economic and environmental benefits.

This study was conducted in one of the private orchards affiliated to Al-Nasr District in Dhi Qar Governorate for the year 2024-2025. To study the effect of foliar fertilization with humic acid at three levels (0, 1.5, 3) g. L-1 and spraying with anti-transpiration (Nautilus) at three levels (0, 1, 2) ml. L-1 on the vegetative growth characteristics of local lemon trees. The results obtained can be summarized as spraying with humic acid at the level of (3 g. L-1) had a significant effect on the vegetative characteristics of the plant (leaf area, stem diameter, number of leaves, number of branches, plant length) compared to the comparison coefficient. Likewise, spraying with Nautilus at the level of (2 ml. L-1) had a clear significant effect on the vegetative characteristics studied for local lemon trees compared to the comparison coefficient. The two-way interaction between the study treatments had a clear significant effect on the H2I2 treatment (3 g/L-1 x 2 ml/L-1) in most of the studied traits.

As a result of scientific research conducted in this article, the positive effects of two different planting methods, mineral fertilizer rates, and foliar iron-containing additional fertilizers on the iron content of flour, bran, and grain were studied.

The climate of our country is suitable for wheat cultivation everywhere, but there is variation from one region to another. Nowadays, the greatest risk in wheat production is posed by extreme weather conditions, but next to them the other key issue of successful growth is the correct nutrient supply. In the present work, the results of the nutrient supply experiment conducted in 2017 and 2022 at the Research Institute of Kompolt of the predecessor institution of MATE are presented. The experiment was set up on small plots, in 4 replications, with Latin square arrangement. In the experiment the effect of NPK doses were examined on the growth of the plants and on the yield in four treatments (three levels of nutrient supply plus control treatment). Each plot was divided into two parts, and one part of each treatment was supplemented with foliar fertilization. The main goal of our experiment is to determine the optimal amount and content of fertilizer, which can give the highest yield in different crop years among the given ecological conditions. We measured the plant height at full maturity, the amount of the yield and the different quality parameters. We found that the highest yield was given by treatment of “growing area specific” fertilizer supplemented with foliar fertilizer.