Foliar Fertilizer Application Research Articles

Agronomic biofortification of maize and beans in Kenya through selenium fertilization.

Deficiency in calcium, zinc, selenium, and iodine remains a major health issue in Africa. A selenium (Se) status survey conducted in central Kenya highlands revealed a high risk of dietary Se deficiency. This study investigates the effect of soil and foliar Se fertilizer application on Se concentration in maize and bean grains. It further tests the combination of Se fertilizer with phosphorus and nitrogen fertilizers, and with zinc and iodine fertilizers. Selenium fertilization results in a significant increase in Se concentration in grains. For the soil application, Se concentration increases on average by 3µgkg-1 in maize and by 10µgkg-1 in beans, for each gram of Se applied as sodium selenate. Foliar Se fertilization is more effective and increases Se concentration in grains on average by 18µgkg-1 in maize, and by 67µgkg-1 in beans. Total soil phosphorus/availability appears as an important factor influencing soil Se availability. Addition of phosphorus fertilizers positively affects the impact of Se fertilization in locations with low soil P, Fe, and Al. A Se + Zn + I fertilizer combination does not affect the impact on Se concentration in grains. Fertilizing beans alone is found to be more efficient compared to fertilizing only maize. In locations at high risk of dietary Se deficiency, foliar application at 10g Se ha-1 on beans or 31g Se ha-1 on maize is sufficient to achieve adequate daily dietary Se intake. The study points towards a multi-mineral agronomic biofortification, based on a site-specific biofortification strategy.

Exogenously Applied Bio-Stimulant and Synthetic Fertilizers to Improve the Growth, Yield and Fiber Quality of Cotton

The effects of exogenously applied Moringa oleifera leaf extract (MLE), nitrogen and potassium were studied on the productivity and quality of two cotton cultivars (CIM-573) and transgenic Bt cotton (CIM-598). The Randomized Complete Block Design (RCBD) factorial experiment was conducted at Bahauddin Zakariya University, Multan, Pakistan (30.2639 °N, 71.5101 °E; 123 m asl), during 2016 and 2017, with three replications. The analysis of variance revealed the significance of cotton cultivars and foliar applications for the majority of traits studied, in both years. The CIM-573 had superiority for most of the traits studied in 2016 and 2017 trials, while the CIM-598 cultivar had significantly higher record for chlorophyll content, seed cotton yield, mean boll weight, and seed index in 2016 and sympodial branches per plant in 2017. Foliar application of Moringa Leaf Extract (MLE) and synthetic fertilizers showed significant differences for the traits studied compared to the distilled water. Exogenous application of MLE has a positive effect on photosynthetic and enzymatic activities that improve the efficiency of nutrients that are utilized, thereby improving the growth, seed cotton yield and quality of cotton cultivars tested. All the interaction effects had a significant influence on the traits studied, except ginning percentage in 2016. The interaction between the conventional cotton cultivar (CIM 573) and exogenous application of MLE + nitrogen + potassium had significantly higher effect on plant height, cotton yield, staple length, fiber maturity, and fiber strength for the 2017 trial and was superior for the quality parameters in 2017. The interaction of the Bt cotton cultivar (CIM 598) and the foliar application of MLE + nitrogen + potassium had superiority in cotton yield, yield components and the quality parameters in the 2017 trial. Both the CIM 573 and CIM 598 cotton cultivars had consistent expressions for all quality traits studied, although they did fluctuate in their expression to these agronomic traits between the field trials of 2016 and 2017. Additive gene effects could be the explanation for the unstable effects of yield and the related traits in the different environmental conditions of the field trials in the two years. Our results suggest that the exogenous application of MLE alone and in combination with nitrogen and potassium could be used to improve the productivity and the quality of these cotton cultivars. The correlation coefficients indicate strong associations between the agronomic and quality traits, indicating that one or more yield parameters could be used as selection criteria to improve the productivity and quality of cotton.

Evaluation of the nutritional profile of sweet maize after herbicide and foliar fertilizer application

Intensive weed management is required to meet the growing demands of sweet maize production. Herbicide application is inevitable in sweet maize production, while foliar fertilizer is commonly used in cropping in order to improve crop yield and quality. The effect of nicosulfuron and mesotrione, with and without foliar fertilizer, on the content of phytochemicals (i.e. carotenoids, tocopherols and free phenolic acids) in the kernels of three sweet maize hybrids was evaluated. Herbicides applied alone mainly improved the nutritive profile of the sweet maize kernel. The application of herbicides in combination with foliar fertilizer showed a high variability in the concentration of carotenoids, tocopherols and free phenolic acids. The significant change in the content of phytochemicals was induced by the applied treatments, but it is also genotype-dependent, which was also confirmed by the Principal Component Analysis.

Benefits of organic fertilizers spray on growth quality of chili pepper seedlings under cool temperature

In this study, effects of foliar application (with constant 0.2% concentration) of chemical NPK (N20:P10:K20) and organic fertilizers of Biomin (an organic aminochelate fertilizer), Humifolin (a humic acid based fertilizer), Biomin + Humifolin, a synthetic macro-micro mixture, soil application of NPK (600 mg.kg−1 of the N20:P10:K20 formulation), and a no fertilizer control were evaluated on growth and quality of chili pepper (Capsicum annuum var annuum) seedlings under greenhouse conditions with cool temperature of 15 ± 3 °C. The results showed that most growth and quality traits were best improved by foliar application of Biomin aminochelate followed by Humifolin fertilizer. Higher values for leaf area, leaf number, chlorophyl index, root and shoot biomass, and leaf concentration of soluble sugars, N, K, Ca, and Zn, were attributed to foliar application of Biomin and Humifolin. The mixture of Biomin + Humifolin had reduced values of those parameters indicating possible negative interaction when these two organic fertilizers are mixed.

Effect of foliar application of compost water extract, humic acid, EDTA and micronutrients on the growth of fenugreek plants under sandy soil condition

Foliar application of liquid organic fertilizer, compost water extract, combined with micronutrients solution in sulfate form, EDTA form or humic acid form gave the highly significant values for fenugreek plants height and weight of seeds. Seven treatments such as compost tea, every three forms of micronutrients and three combinations (1:1) of compost tea with each micronutrients form besides untreated control were applied as foliar spray twice to Trigonella plants at 35 days and at 70 days from sowing. The plant height increments were by 48 and 50% for sulfate form with compost tea, by 67 and 69% for humic acid form with compost tea and by 66% for EDTA form with compost tea for the first and second season, respectively. The values of fenugreek weight of seeds for combined compost tea in both seasons were by (63 and 41%) with sulfate mineral solution, by (76 and 50%) with EDTA and by (90 and 65%) with humic acid, respectively. It is obvious from the results that using compost tea in a combination with micronutrients forms can reduce the chemical fertilizer dose by 50% and enhance the fenugreek growth better than the chemical fertilizer does.

Do Fertilizers and Irrigation Disruption Change Some Physiological Traits of Safflower?

To investigate the effects of nanofertilizers and biofertilizers on the morpho-physiological and biochemical traits of safflower under full irrigation and water deficit stress, this study was carried out as a split-plot experiment based on a Randomized Complete Block Design with three replications at Urmia University in 2015. The main plot was full irrigation (control) and irrigation disruption at heading, flowering, and grain filling stages. Fertilizers, including control (without fertilizer), biofertilizer, water spray, foliar application of nanofertilizers, chemical fertilizers, and combined application of fertilizers, were assigned to the subplot. Plants under full irrigation and combined fertilizers had maximum height and chlorophyll a, whereas the lowest ones were obtained in irrigation disruption at the heading stage and control treatments. The maximum oil content (28.41%) was detected in irrigation disruption at the grain filling stage and nanofertilizer treatment, the lowest (21.96%) was obtained at irrigation disruption at the flowering stage and water spray treatment. The highest proline (397.21 µg g−1 fresh leaf) was found in irrigation disruption at the grain filling stage and water spray treatment, and the lowest (154.68 µg g−1 fresh leaf) was obtained at full irrigation and water spray treatment. Irrigation disruption at the heading stage and control treatments decreased carbohydrate content of fresh leaves by 86.54% compared to full irrigation and the combined fertilizers treatment. Irrigation disruption increases saturated fatty acids (palmitic and stearic acid) and decreases vitamin E and linoleic acid. The combined application of fertilizers significantly increased safflower oil quality. Overall, concerning the obtained highest oil percentage (28.41%), irrigation disruption during grain filling reduced water consumption and application of combined fertilizer via improving oil quality, so it is recommended to farmers.

Effect of foliar application of potassium fertilizers on soybean plants under salinity stress

Abstract Soybean, one of the major food and fodder crops, yield is significantly reduced by different abiotic and biotic stresses, and salinity is one of the major abiotic stresses. The research objective of this study was to investigate the effect of foliar application of potassium chloride and potassium sulfate fertilizers at the early growth stage of soybean under medium (6 dS/m) and high (12 dS/m) salinity stresses. The effect of fertilizer application was measured on the bases of plant growth, levels of antioxidant activities, total polyphenol, flavonoid, chlorophyll, and carotenoid contents. Potassium sulfate showed better positive effect on the antioxidant activities, polyphenol, flavonoid, carotenoid, and chlorophyll contents compared to those of potassium chloride although the contribution was not noteworthy in comparison to the fertilizer unsprayed plants. The results of this study implied that foliar applications of 2.5% potassium fertilizers could not help reduce the negative effect of salinity stress at the early stage of soybean growth. This study suggests further researches using different concentrations of fertilizers at different plant growth and development stages.

Mineral fertilizers with iron influence spring rape, maize and soil properties

ABSTRACTBecause of low content of available iron (Fe) in soils and its poor mobility in plants, iron fertilization is necessary. Different forms of iron (mineral salts, chelates, nanomaterials) and fertilization strategies (soil and foliar application of solid or liquid fertilizers) are used. The effect of solid mineral fertilizers (A: a mixture of ammonium nitrate and dolomite; B: a mixture of ammonium nitrate and sulfate) enriched with iron sulfate was assessed during a three-year pot experiment. Iron addition did not change the yield of spring rape (first year) or maize (second and third year) significantly, and the effect on iron content in the plants was ambiguous. Fertilizer B with iron had the greatest yield-forming effect, increasing the yield of aboveground parts by 355–874%, and of roots by 211–692% in particular years. All fertilizers (especially containing sulfur) acidified the soil. After the experiment, pH of the soil fertilized with sulfur was 4.1, and of the unfertilized soil – 5.2. Iron addition increased the content of mobile and exchangeable iron in the soil by 12–110% and 2–58%, respectively, but not the content of the fraction bound to MnOx. Combination of sulfur and iron fertilization has a potential to improve soil abundance and plant yield.

Development of liquid urea ammonium nitrate fertilizer foliar application system for enhanced nutrient use efficiency

A tricycle type manually operated foliar applicator was developed with ground clearance of 74.15 cm that can be operated on standing wheat crop having row spacing of 20-22 cm. The physical properties of urea ammonium nitrate (UAN) with 3% N were found nearly equal to water with respect to dynamic viscosity, surface tension and specific gravity of UAN. Based on pressure, discharges requirement and corrosiveness of UAN, reciprocating typePVC pump (2 no.) with capacity of 4.53 l/min each was selected for the sprayer. Three type of nozzles, i.e. flat fan, stream jet SJ7 and stream jet SJ3 were evaluated in terms of discharge, spray pattern and spray angle at different heights and pressures. Spray pattern and uniformity of spray distribution of nozzles (flat fan, stream jet SJ3 and SJ7) were determined on patternator test rig. Flat fan nozzles showed most uniform pattern at 2 kg/cm2 pressure and 500 mm nozzle height, whereas streamjet SJ7 showed maximum uniformity at 1.6 kg/cm2 and 600 mm height. Streamjet SJ3 nozzles were found suitable for low boom height and directed application of fertilizer. Variation in discharge of nozzles among the boom was observed less than 10% while operated in field. Field capacity of the developed foliar applicator was found 0.3 ha/h. Operating pressure of 1.5 kg/cm2 was found ergonomically suitable with an average heart rate and energy expenditure of 119 beats/min and 26.7 kJ/min, respectively for operating the prototype. The break-even point (BEP) and payback period (PBP) of developed foliar applicator were estimated as 113.43 h/year and 4 years at the operational cost of Rupees 94.68/ha.

Leaf count overdispersion in coffee seedlings

ABSTRACT: Coffee crops play an important role in Brazilian agriculture, with a high level of social and economic participation resulting from the jobs created in the supply chain and from the income obtained by producers and the revenue generated for the country from coffee bean export. In coffee plant growth, leaves have a determinant role in higher production; therefore, the leaf count per plant provides relevant information to producers for adequate crop management, such as foliar fertilizer applications. To describe count data, the Poisson model is the most commonly employed model; when count data show overdispersion, the negative binomial model has been determined to be more adequate. The objective of this study was to compare the fitness of the Poisson and negative binomial models to data on the leaf count per plant in coffee seedlings. Data were collected from an experiment with a randomized block design with 30 treatments and three replicates and four plants per plot. Data from only one treatment, in which the number of leaves was counted over time, were employed. The first count was conducted on 8 April 2016, and the other counts were performed 18, 32, 47, 62, 76, 95, 116, 133, and 153 days after the first evaluation, for a total of ten measurements. The fitness of the models was assessed based on deviance values and simulated envelopes for residuals. Results of fitness assessment indicated that the Poisson model was inadequate for describing the data due to overdispersion. The negative binomial model adequately fitted the observations and was indicated to describe the number of leaves of coffee plants. Based on the negative binomial model, the expected relative increase in the number of leaves was 0.9768% per day.

Foliar fertilization on the production of grafted dwarf cashew seedlings

ABSTRACT Foliar fertilization is an important agricultural technique that has stood out for its ease of use and can contribute to the production of high-quality and -vigor cashew seedlings. The objective of this study was to evaluate the effect of foliar fertilizer rates and time of application on ‘BRS 226’ dwarf cashew seedlings after grafting. The experiment was carried out in a completely randomized design, with five treatments and 24 replicates. Each experimental unit consisted of one plant. The commercial product (NPK 20-20-20) was used at the recommended rate for fruit crops in general, 2.5 g L-1. Foliar fertilizer applications at 45 and 60 days after grafting (DAG), with 50% of the recommended rate (1.25 g L-1), or at 80 DAG, with 100% of the recommended, promoted increments of 9% and 13% in the total dry mass, respectively, in comparison to unfertilized plants. Besides that, at 80 DAG the foliar fertilizer application caused significant difference in the B contents, allowed obtaining better quality ‘BRS 226’ grafted dwarf-cashew seedlings. In the production of grafted seedlings of ‘BRS 226’ dwarf-cashew, it’s recommended to foliar fertilization at 45 and 60 days after grafting, with 1.25 g L-1 of the product based on NPK 20-20-20; or a single dose application 2.5 g L-1 at 80 days after grafting.

Bacterial population dynamics after foliar fertilization of almond leaves

To describe the effects of foliar fertilizer application on the bacterial populations of almond tree leaves. We applied a commercially available foliar fertilizer or a water control onto the leaves of almond trees and collected leaves after 1, 7, 14 and 56 days and examined their bacterial populations by 16S rRNA gene sequence analysis. After 1 day, we observed significant differences in 3 of the 4 predominant bacterial phyla, and 5 of the 13 predominant bacterial families. After 7days, we observed significant differences in all of the predominant phyla, and 8 of the 13 predominant families. After 14 days, the number of significant differences decreased, and after 56 days only 2 of the 13 predominant families differed significantly. Foliar fertilization significantly altered the bacterial population structure of almond leaves as compared to the water control. While most of the observed perturbation was transient, significant differences remained after 56 days. This is the first report describing the effects of foliar fertilization on the bacterial populations of almond leaves and provides new insights as to how this process alters the leaf bacterial population structure.

Foliar Application of Di-Ammonium Phosphate and Triple Super Phosphate on Lentil at Drought Prone Area of Bangladesh

A field experiment was conducted to investigate the effect of foliar application of DAP and TSP on yield and yield attributing characters of lentil. Foliar application of DAP and TSP was performed at flowering and pod formation stages of lentil. Results revealed that maximum fresh weight of plant, nodule number and dry weight of nodule were recorded in F2 treatment at 50% flowering stage of lentil. F1 treatment produced higher branch plant-1 (2.66), pod plant-1(106.47) and seed yield (0.72 t ha-1) of lentil. DAP increased 6% higher grain yield than no foliar application of fertilizer. It may be suggested that foliar application of DAP is a better technology for increasing lentil production in drought prone area of Bangladesh.
 Journal of Bangladesh Academy of Sciences, Vol. 42, No. 2, 211-214, 2018

Effect of soil and foliar application of nitrogenous fertilizers on growth and budding of sweet orange

Effect of soil and foliar application of nitrogenous fertilizers on growth and budding of sweet orange

Statement of Foliar Fertilization Impact on Yield, Composition, and Oxidative Biomarkers in Rice.

In rice crops, fertilization is a naturalized practice, although inefficient, that could be improved by applying foliar fertilization. Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are products of α-linolenic acid peroxidation, useful as biomarkers of oxidative degradation in higher plants. The objective was to determine the effect of the foliar fertilization on the concentration of PhytoPs and PhytoFs and its relationships with modifications of yield and quality of rice productions. It was described that the concentration of biomarkers of stress decreased with the application of foliar fertilization, being the response significantly different depending the genotypes and compound monitored. Moreover, fertilization did not modify significantly the parameters of yield (961.2 g m-2), 1000 whole-grain (21.2 g), and protein content (10.7% dry matter). Therefore, this is the first work that describes the effect of fertilization on PhytoPs and PhytoFs in rice genotypes and reinforces the capacity of these compounds as biomarkers to monitor specific abiotic stress, in this case, represented by nutritional stress.

RESPONS PERTUMBUHAN TANAMAN HIAS ANTHURIUM ‘GELOMBANG CINTA’ (Anthurium plowmanii) PADA BEBERAPA KONSENTRASI BAP DAN FREKUENSI PEMBERIAN PUPUK DAUN

Ornamental plants anthurium wave love great demand of society because the leaves are beautiful, unique and interesting. The edges of the leaves of anthurium generally with characteristic wavy. Anthurium plant growth stimulation can be enhanced by the application of growth regulators BAP and foliar fertilizers. The purpose of this study was to obtain a concentration of growth regulators BAP and best foliar fertilizer for growing ornamental plants anthurium. Experiments was carried out in the plant tissue culture laboratory of the Faculty of Agriculture, Andalas University from November 2015 to February 2016. Materials used in the love wave anthurium seeds, plant media are a mixture of soil, sand, compost 1: 1: 1 (v / v). Two-factor factorial experiment arranged in completely randomized design with three replications. The first factor was the concentration of BAP (0, 2.5, 5.0 and 7.5 mg/L) and the second factor was the frequency of giving leaf fertilizer (0, 1, 2 times). The variables observed were plant height, leaf width, root length and fresh weight of plants. The data were analyzed by analysis of variance followed by Honestly Significant Difference test 5%. The results showed that there is an interaction between BAP and the frequency of leaf fertilizer application to plant height and root length. The best BAP 2.50 mg/L for leaf width growth and 5.0 mg/L best to increase the fresh weight of plants. The best BAP concentration of 2.50 mg/L for leaf width growth and 5.0 mg/L is best for increasing the fresh weight of plants. Application of leaf fertilizer with a frequency of 2 times shows the highest plant height Keywords: Anthurium, BAP, Concentration, Foliar fertilizer, Frequency

Application of foliar fertilization in seed breeding of sugar beet hybrids

Three-year research of foliar fertilization of the mother and seed plants of the MS-component of the sugar beet hybrid RMS-120 with microfertilizers showed a significant positive effect of the latter both on the mother’s crops and on planting of seed plants. So, in the first year of the seed-growing process (cultivation of planting material) this was expressed in maintaining a high density of standing beet plants for harvesting, increasing the yield coefficient of planting material from 4,34 to 6,04. At the storage stage of mother’s roots, an improvement in its preservation was noted from 85,0 (control) to 91,7 %. In the second year of seed production (growing of seed plants), the yield of the resulting hybrid seeds was increased from 1,44 (control) to 1,91 t/ha and the improvement of their sowing qualities - germination and good quality to 89,0 and 93,5 % respectively (17,5 % above the control).

Bio-Boron Fertilizer Applications Affect Amino Acid and Organic Acid Content and Physiological Properties of Strawberry Plant

The effects of boron and plant growth promoting bacteria (Bio-B) on the some of physiological parameters with amino acid and organic acid of strawberry cv. Fern were investigated under field conditions. The study treatments were soil, foliar, and soil + foliar applications as main plot and two Bio-B (control and plant growth promoting rhizobacteria; Azospirillum brasilense 1 × 109 cfu ml−1 + 10% boron as Di-SodyumOktaboratTetraHidrat) fertilizer applications as subplot in complete randomized block design with four replicates. Bio-B fertilizer was applied in three methods such as soil, foliar and soil + foliar application methods on strawberry. Two years data from the present study reported that the use of Bio-B significantly increased chlorophyll, photosynthesis, stomatal and membrane permeability, amino acid and organic acid of strawberry leaf. Soil + foliar applications of Bio-B fertilizer increased to strawberry yield compared to the control by 65.9%. Foliar applications of Bio-B fertilizer increased chlorophyll and stomatal permeability in comparison to the control by 17.62 and 56.52%, respectively. However, soil + foliar application of Bio-B fertilizer increased membrane permeability and photosynthesis compare to those under the control 24.80 and 23.32%, respectively. Amino acid content of strawberry was increased (23.45%) and organic acid amount was increased (23.45%) under soil application of Bio-B fertilizer compare to those under the control. The results of this study concluded that Bio-B fertilizer application was positively associated with strawberry yield and increased the potential to chlorophyll, photosynthesis, stomatal and membrane permeability, amino acid, organic acid content under field conditions.

The Effect of Concentration and Timing of Application of Green Tonik Foliar Fertilizer on theGrowth and Yield of Cucumber (Cucumis sativusL.) Mercy Variety

This experiment aims to: (1) to study of the effect of concentration and application timing of Green Tonik foliar fertilizeras well as their interaction on the growth and yield of cucumber plants; and (2) to find proper concentration and application timing of Green Tonik foliar fertilizer for better growth and yield of cucumber plants.The experiment carried out from March 2016 to May 2016, in the Village of Muara Bengkal Ilir, Muara Bengkal Subdistrict, East Kutai District. It applied Completely Randomized Block Design with factorial experiment 4 x 3 and three replications. The first factor was the concentration of the Green Tonik foliarfertilizer (K) consists of 4 levels, namely: no Green Tonik foliar fertilizer application (k0), 1 ml l-1 water(k1), 2 ml l-1 water(k2), and 3 ml l-1 water(k3). The second factor wasinterval of the application time of Green Tonik foliar fertilizer(W) consists of 3 levels: 5, 10, 15, 20, and 25 days after planting (w1), 7, 14, 21, 28, and 35 days after planting (w2), and 10, 20, 30, 40, and 50 days after planting (w3).Result of the experiment revealed that : (1) concentration of Green Tonik foliar fertilizer application was affected significantly to very significantly on plant lenght at 30 and 45 days after planting, days of plant flowered, number of fruits per plant, diameter of fruit, weight of one fruit, and production of fruits, but no significant on the plant lenght at 15 days after planting, and lenght of fruit. The highest production of fruit is attained by the 2 ml l-1 water (k3), namely 54,67 Mg ha-1, In reverse, the least production is attained by without Green Tonik foliar fertilizer (k0), namely 24,00 Mg ha ̵ ¹; (2) interval of Green Tonik foliar fertilizer application time was no significant on the plant lenght at 15 and 45 days after planting, days of plant flowered, number of fruits per plant, lenght of fruit, diameter of fruit, weight of one fruit, and production of fruit, but affected significant on the plant lenght at 30 days after planting; and (3) interaction between concentration and application timing of Green Tonik foliar fertilizer was no significant on the all parameters observed.

Foliar application of potassium-based fertilizer improves strawberry fruit quality

Among the different mineral nutrients, potassium (K) is recognized as the macronutrient that most strongly affects the quality parameters of crops. An adequate K nutrition is in fact associated with increased fruit size, enhanced nutraceutical properties (e.g., content of sugar, organic acids, antioxidants), improved color and increased shelf life for many agricultural products. Previous studies have shown that, in controlled conditions, the foliar application of K-based fertilizers during the fruit development period could improve fruit quality; however, it is not clear whether such positive results can also be obtained in field-cultivated plants. For these reasons, the aim of the present study was to assess if the repeated applications of K-based fertilizers during the production period (mid-June to late August) might affect the quality parameters of strawberry (Fragaria × ananassa 'Murano') fruits. Frigoplants, transplanted in April, were cultivated in grow bags on cocopeat (8 plants per linear meter) and treated foliarly spraying K(2)SO(4) (6 g L(-1)) either once or twice a week. Control plants were sprayed with distilled water. As expected, foliar K-fertilization increased the K concentration by 8-11% in fruits and by 7-5% in leaves according to the frequency of application (once and twice a week, respectively). In addition, strawberry fruits exhibited an enhanced total soluble solids content (approximately 12%) and sweetness index (approximately 13%). Conversely, other nutraceutical compounds (e.g., phenolics, flavonoids and flavonols) as well as the fruit yield were not affected by K treatments, regardless the fertilization levels. In conclusion, results here presented show that at the field scale the foliar K-fertilization during the development of strawberries can enhance the quality and the nutraceutical value of fruits.