Foliar Potassium Research Articles

Cotton Response to Foliar Potassium Application in South Texas Dryland

Potassium (K) deficiency is common in cotton (Gossypium hirsutum L.)-growing areas. This study aims to investigate the effects of different rates of foliar K fertilizer application on three cotton varieties: NG 5711 B3XF (V1), PHY 480 W3FE (V2), and FM 1953GLTP (V3). Potassium fertilizer was dissolved in water and was foliar-applied at 34, 50, and 67 kg ha−1. Cotton plant height (CH) and canopy width (CW) were monitored throughout the growing season. The results showed that foliar K fertilizer application significantly impacted the CH and CW in dry years. Although insignificant, the cotton lint yield increased by 15% and 20% with 34 and 50 kg ha−1 in 2020 and by 9% and 7% with 50 and 67 kg ha−1 in 2021, indicating the potential for improved lint yield with foliar K application in rainfed production systems. Similarly, variety V3 had significantly greater lint and seed yields than V1 in 2020. The average lint yield among the varieties was 32%, and the seed yield was 27% greater in 2020 than in 2021. The cotton fiber color grade was significantly greater at 50 kg ha−1 in 2020 and 67 kg ha−1 in 2021. Cotton variety significantly affected color grade, uniformity, staple length, Col, RD, and Col-b contents in 2020 and 2021. The results suggest that foliar K application can enhance cotton production in rainfed production systems. However, more research is required to quantify varietal and foliar K application rates for improved lint yield and quality.

Effects of Foliar Potassium Supplementation on Yield and Nutrient Uptake of Plant Sugarcane

Effects of Foliar Potassium Supplementation on Yield and Nutrient Uptake of Plant Sugarcane

Optimizing wheat productivity through integrated management of irrigation, nutrition, and organic amendments

Enhancing wheat productivity by implementing a comprehensive approach that combines irrigation, nutrition, and organic amendments shows potential for collectively enhancing crop performance. This study examined the individual and combined effects of using irrigation systems (IS), foliar potassium bicarbonate (PBR) application, and compost application methods (CM) on nine traits related to the growth, physiology, and yield of the Giza-171 wheat cultivar. Analysis of variance revealed significant (P ≤ 0.05) main effects of IS, PBR, and CM on wheat growth, physiology, and yield traits over the two growing seasons of the study. Drip irrigation resulted in a 16% increase in plant height, leaf area index, crop growth rate, yield components, and grain yield compared to spray irrigation. Additionally, the application of foliar PBR at a concentration of 0.08 g/L boosted these parameters by up to 22% compared to the control. Furthermore, the application of compost using the role method resulted in enhanced wheat performance compared to the treatment including mix application. Importantly, the combined analysis revealed that the three-way interaction between the three factors had a significant effect (P ≤ 0.05) on all the studied traits, with drip irrigation at 0.08 g PBR rate and role compost application method (referred as Drip_0.08g_Role) resulting in the best performance across all traits, while sprinkle irrigation without PBR and conventional mixed compost method (referred as sprinkle_CK_Mix) produced the poorest results. This highlights the potential to synergistically improve wheat performance through optimized agronomic inputs.

Agaricus bisporus Compost, Foliar Potassium, and Boron Applications for Enhanced Flowering and Yield of Cucurbita pepo L. Under Field Conditions

Agaricus bisporus Compost, Foliar Potassium, and Boron Applications for Enhanced Flowering and Yield of Cucurbita pepo L. Under Field Conditions

Integrated foliar application of potassium with soil applied nitrogen and phosphorus improves productivity of chickpea (Cicer arietinum L.)

Optimal nitrogen and phosphorus fertilization can enhance growth and yield of chickpea. However, little is known on nitrogen and phosphorus fertilization supplemented with foliar application of potassium on productivity of chickpea. Therefore, a study was designed with the aim to explore–efficiency of soil applied nitrogen and phosphorus in combination with foliar potassium nutrition on performance of chickpea. The chickpea cultivar Bittle-98 was grown in plastic pots filled with 10 kg of soil following Randomized Complete Design (RCBD). Various treatments comprising control (T1), nitrogen 160mg/pot (T2), phosphorus 385mg/pot (T3), nitrogen 160mg/pot + 0.75% K2SO4 foliar (T4), phosphorus 385mg/pot +0.75% K2SO4 foliar (T5), and nitrogen 160mg/pot + phosphorus 385mg/pot+0.75% K2SO4 foliar (T6) were tested. The T6 resulted in maximum plant height (64.37cm), number of pods per plant (45.46), seeds per pod (1.40) 100-seed weight (18.03g), SPAD counts (34.52), seed yield (35.80g/pot), and biological yield (85.24g/pot) than rest of the treatments. The yield in response to T3 was significantly higher than T2, mainly because of higher pods frequency, indicating that phosphorus is more imperative than nitrogen to harvest maximum yield of chickpea. The yield obtained was in the order of T6>T5>T4>T3>T2. It is revealed that soil applied nitrogen plus phosphorus supplemented with foliar potassium is an effective strategy to harvest higher yield of chickpea. Recommended soil application of nitrogen and phosphorus with foliar 0.5% K2SO4 is suggested to harvest maximum yield of chickpea.

Synergistic effects of biochar and potassium co-application on growth, physiological attributes, and antioxidant defense mechanisms of wheat under water deficit conditions

Global wheat production faces a severe threat from drought stress, necessitating innovative strategies for enhanced crop resilience. This study examined the synergistic impact of biochar and potassium co-application on the growth, physiological attributes, and antioxidant defense system of wheat under water deficit conditions at crown root initiation (CRI), anthesis, and grain development stage. Drought-induced reactive oxygen species (ROS) accumulation, particularly pronounced at the CRI stage, adversely affected all growth stages. At CRI, co-application of biochar and foliar potassium delivered significant improvements in growth parameters, including increased plant height (15.4%), spike length (50%), grain yield (43.0%), photosynthetic performance (chlorophyll content 125.8%), and relative water content (11.2%), compared to untreated drought-exposed counterparts. The combined application of biochar and potassium effectively reduced hydrogen peroxide production, electrolyte leakage, proline accumulation, and malondialdehyde generation, while increasing relative water content and glutathione levels under both well-irrigated and drought stress conditions. Furthermore, the combined biochar and potassium treatment was effective in mitigating oxidative stress and enhancing physiological resilience in wheat, particularly during the anthesis stage of drought stress. Specifically, the combined treatment ameliorated the effects of drought by reducing ROS levels through enhanced antioxidant enzyme activities and elevating osmoprotectants levels. The synergistic modulation of tissue osmotic balance and relative water content holds promise for mitigating drought-induced stress, offering an innovative and practical strategy for resilient wheat production in water-limited environments.

Enhancing drought, heat shock, and combined stress tolerance inMyrobalan29C rootstocks with foliar application of potassium nitrate.

Drought and heat stress are significant concerns to food security in arid and semi-arid regions, where global warming is predicted to increase both frequency and severity. To cope with these challenges, the use of drought-tolerant plants or technological interventions are essential. In this study, the effects of foliar potassium nitrate (KNO3) application on the stress tolerance and recovery of Myrobalan 29C rootstocks (Prunus cerasifera Ehrh.) were evaluated. These rootstocks are widely recognized for their adaptability and are extensively used in fruit production. To assess their response, the rootstocks were subjected to drought, heat shock, or a combination of both stressors. Additionally, they were treated with 1.0% KNO3 via foliar application. Throughout the stress and recovery periods, various morphological, physiological, and bio-chemical parameters were measured. Based on our results, KNO3 treatment improved LRWC, Chl stability, SC, and key stress markers like proline, MDA, H2O2, along with antioxidant enzymes CAT, SOD, POD during both stress and recovery phases. Moreover, our results emphasized KNO3's critical role in hormone regulation under stress. KNO3 application significantly altered hormone levels, notably increasing ABA during drought and heat shock stress, essential for stress response and adaptation. In contrast, IAA, GA, and cytokinin's significantly increased during the recovery phase in KNO3-treated plants, indicating improved growth regulation and stress recovery. In addition, KNO3 application improved the recovery process of the rootstocks by restoring their physiological and biochemical functions. This study suggests that the application of foliar KNO3 is an effective technique for enhancing the drought and heat tolerance as well as the recovery of Myrobalan 29C rootstocks. These results hold significant value for farmers, policymakers, and researchers, as they offer crucial insights into the development of drought-tolerant crops and the management of climate change's adverse effects on agriculture.

Physiology and development of grafted dwarf cashew seedlings under different fertilization doses and irrigated with saline water

Salinity is one of the primary challenges faced by irrigated agriculture in semi-arid regions. This study aimed to investigate the effects of fertilization on the development of cashew seedlings irrigated with water of varying salinity levels. The research was conducted in a protected environment at Embrapa Agroindústria Tropical, Fortaleza, using grafted seedlings of the BRS 189 clone on CCP 06 rootstock. The treatments resulted from the combination of three levels of NPK fertilization (control - without fertilization, 50% less than conventional nutrition, and 100% of conventional nutrition used by the crop), which was incorporated into the substrate before sowing CCP 06, with four salinity levels (ECa of 0.8, 4.0, 7.0, and 10.0 dS m-1) of the irrigation water for the seedlings. Gas exchange, assimilate accumulation, growth, and nutrient content in the leaves, stems, and roots of the seedlings were evaluated 90 days after grafting. The data were subjected to analysis of variance, and when a significant effect was observed, the Tukey test was performed, while quantitative data were subjected to regression analysis. Overall, fertilization levels did not influence seedling growth. Fertilization did not interfere with photosynthate production, which performed better when the seedlings were subjected to a salinity of 7.0 dS m-1. The application of NPK to the substrate resulted in higher levels of nitrogen in the leaves, while phosphorus content decreased, and foliar potassium was not influenced by fertilization.

Physiological and Agronomic Implications of Foliar Potassium Application on Sunflower Productivity in Calcareous Soils

Physiological and Agronomic Implications of Foliar Potassium Application on Sunflower Productivity in Calcareous Soils

Rice resistance against Bipolaris oryzae infection is mediated by lower foliar potassium concentration

AbstractBrown spot, caused by Bipolaris oryzae, is a very important disease of rice. This study investigated the effect of potassium (K) on rice resistance to brown spot. The working hypothesis tested was that higher foliar K concentration could allow plants to respond more efficiently against fungal infection. Plants were grown in nutrient solution amended with three K rates (0.5, 1.0 and 2.5 mM) and noninoculated or inoculated with B. oryzae. The photosynthetic performance of plants, activities of defence and antioxidant enzymes and the concentrations of reactive oxygen species, phenolics and lignin were determined. Foliar K concentration was significantly higher by 38% and 91% for plants supplied with 1.0 and 2.5 mM K, respectively, compared to plants supplied with 0.5 mM K. Brown spot severity was significantly higher (≥20%) for plants supplied with 1.0 and 2.5 mM K than those supplied with 0.5 mM K (≤15%). Higher brown spot severity for plants supplied with 2.5 mM K resulted in changes in the photosynthetic apparatus, reduced chlorophyll a + b and carotenoids concentrations, and higher production of hydrogen peroxide and superoxide anion radical. In contrast, higher activities of defence and antioxidant enzymes and more production of phenolics for plants supplied with 0.5 mM K helped them to cope with B. oryzae infection more efficiently. In conclusion, rice resistance against brown spot was achieved by keeping a lower foliar K concentration linked to more active defence reactions, a robust antioxidative system and less damage to the photosynthetic apparatus.

Effect of Irrigation, Phosphorous and Potassium Application on Root Traits, Soil Microbial Growth and Physiology of Green Gram

Aims: To manage the implication of irrigation water at different growth stages coupled with basal phosphorus and foliar potassium application targeting to reduce water stress.
 Study Design: Split split-plot design.
 Place and Duration of Study: Agricultural Research Station, Chatabar, Odisha. India, during 2022-2023 cropping season.
 Methodology: Three irrigation treatments in main plots (I1, I2 and I3) - I1 included three irrigations at vegetative, flowering and pod formation periods, I2 skipped one irrigation at pod formation and I3 skipped at flowering. Sub-plot consisted of phosphorus fertilizer treatments (P1, P2 and P3) providing 100, 85 and 115% recommended dose of P. In sub sub-plots- 2% foliar spray of KCl at vegetative and flower initiation periods. The parameters recorded soil moisture depletion, root traits, microbiological parameters, plant physiological parameters and grain yield.
 Results: The depletion of soil moisture increased with crop growth; I3 depleted at a maximum rate (4.5 mm d-1) followed by I2 (4.1 mm d-1). The enhanced availability of root zone soil moisture improved microbial biomass carbon (MBC) and dehydrogenase activity (DHA). The I1 improved the maximum root tips, forks and crossings; while I3 reduced an overall of 131% of the root traits than I1. The crop growth rate (CGR) and leaf area index (LAI) were also improved according to soil moisture availability; however, I2 merely decreased 8 and 13% in CGR and LAI as compared to I1. P3 improved the maximum of the soil microbiology (MBC and DHA), root improvement and plant physiology. I1P3 produced the highest grain yield of 9.06 q ha-1, although, I2P3 produced was just 7% lower than I1P1.
 Conclusion: The application of three irrigation produced maximum grain yield; while the skipping of one irrigation at pod formation stage with 15% higher P application could provide satisfactory yield where availability of irrigation water is limited.

Effects of row spacing and potassium foliar applications on yield of cotton

AbstractCotton (Gossypium hirsutum L.) is an important crop in drought‐prone central Texas. Foliar potassium (K) application and skip‐row planting have the potential to improve productivity of rainfed cotton in this region. The objective of this study was to quantify the effects of skip‐row planting and foliar K on cotton lint yield, biomass, nutrient uptake, and lint quality in rainfed cotton from 2017 to 2020. Foliar K was applied at 0, 20, and 40 kg ha−1. Row arrangement treatments consisted of two planting geometries: 2 × 1 skip row and standard full row. Cotton yield was not affected by foliar K in all years or by row spacing in 2017, 2019, or 2020. In 2018 alone, there was greater lint yield from skip row (530 kg ha−1) compared to full row (423 kg ha−1). The skip‐row treatment resulted in significantly lower vegetative biomass and vegetative K uptake, but improved fiber quality. While foliar K application did not impact lint yield, total biomass and vegetative nitrogen and phosphorus uptake were increased with foliar K. There were year‐to‐year differences in seed and vegetative biomass, nutrient uptake, and lint quality, likely driven by differences in rainfall, with 2018 being unusually dry. Weather variation had more impact on cotton productivity than either treatment. However, given that the skip‐row treatment increased quality and yield in the driest year while not affecting yield in wetter years makes it a viable option for cotton producers looking to reduce costs and increase profits in drought‐prone regions.

Foliar Mn and Zn Treatments Improve Apple Tree Nutrition and Help to Maintain Favorable Soil pH

The foliar application of micronutrients can improve primary nutrient uptake. As a result, foliar treatments can reduce fertilizer application rates and help to maintain the natural health of soil. Here, we report on the tentative implementation of this approach in an apple orchard located in a temperate climate (JSC “Dubovoye” 52°36′57.1″ N 40°17′04.1″ E; planted in 2002 according to the 6 × 4 m or 417 trees ha–1 cultivar (cv.) Bogatyr grafted on B118 (Budagovskii 118). Manganese treatments augmented foliar nitrogen content and, in certain seasons, foliar phosphorus, whereas zinc treatments enhanced foliar potassium. Low-rate chemical fertilizers application (once in 5 years) on the background of initial high-rate organic fertilization (60 t ha–1 manure) allowed us to retain the optimal soil pH in the experimental orchard.

Stimulating growth, root quality, and yield of carrots cultivated under full and limited irrigation levels by humic and potassium applications

Water stress poses a significant challenge for carrot cultivation, leading to decreased yield and inefficient water use efficiency. Therefore, it is crucial to provide plants with suitable supplements that enhance their stress resistance. In this study, we investigated the effectiveness of humic and potassium applications on carrot growth, yield characteristics, root quality, and water use efficiency under varying irrigation levels. A split-split plot experiment was conducted, with two levels of gross water requirements (GWR) (100% and 80%) assigned to the main plots. The subplots were treated with humic acid through foliar application (Hsp) or soil drenching (Hgd). The sub-subplots were further divided to assess the impact of foliar potassium sources (potassium humate, Kh) and mineral applications (potassium sulfate, K2SO4). The results revealed a substantial reduction in carrot yield under limited irrigation, reaching about 32.2% lower than under GWR100%. Therefore, under limited irrigation conditions, the combined application of Hgd and K2SO4 resulted in a significant yield increase of 78.9% compared to the control under GWR80%. Conversely, under GWR100%, the highest average yield was achieved by applying either Hsp and Kh or Hsp and K2SO4, resulting in yields of 35,833 kg ha−1 and 40,183 kg ha−1, respectively. However, the combination of Hgd and Kh negatively affected the yield under both GWR100% and GWR80%. Nonetheless, applying Kh in combination with Hgd under GWR80% led to improved nitrogen, phosphorus, potassium, potassium/sodium ratio, and total sugar concentrations, while reducing sodium content in carrot roots. Based on this study, it is recommended to adopt GWR80% and treat plants with a combination of Hgd and foliar K2SO4. This approach can help plants overcome the negative effects of water stress, improve yield and root quality, and achieve optimal water use efficiency.

Long-term risk assessment of uprooting and stem breakage under drought conditions and at high N deposition in beech and Norway spruce

Damage by wind in forests has increased in recent decades, counteracting possible growth increases by nitrogen (N) deposition. This is also shown by the long-term forest monitoring data from this study. The main factors affecting uprooting and stem breakage in Fagus sylvatica (L.) (9′846 individual beech trees in 102 plots) and Picea abies (Karst.) (9′168 Norway spruce trees in 72 plots) have been analysed by binomial mixed regression models. Our long-term forest observations showed that drought increased uprooting of beech and increased both uprooting and stem breakage of Norway spruce. In beech, high N deposition interacted with drought, resulting in increased uprooting under drought. In Norway spruce, N deposition increased stem breakage directly. Foliar potassium (K) deficiency increased uprooting of both beech and Norway spruce. Moreover, we found an indirect effect of soil acidification in increasing uprooting of beech by decreasing foliar calcium (Ca) concentrations. In Norway spruce, the soil acidification effect was confounded by foliar K concentrations. In beech, stem breakage increased with higher temperature which can be explained by a temperature-mediated growth increase of white rot fungi. In contrast, temperature was negatively related with stem breakage in Norway spruce, which may be interpreted as an inhibition of the heartrot fungus Heterobasidion at higher temperatures.In summary, drought and high N deposition increase the risk of mechanical damage to both beech and Norway spruce and thus endanger sustainable growth rates. We therefore suggest that wind damage must be taken in account in productivity calculations and carbon budgets of temperate forests.

Evaluation of Agronomic Efficiency with Regional Source of Natural Potassium in the Brazilian Midwest

Brazil plays an important role in global food production, but faces challenges due to its dependence on imported fertilizers. To reduce this vulnerability of the agricultural sector, the use of natural sources such as agrominerals, also known as rock dust, is gaining ground. The objective of this study was to characterize and evaluate a new source of natural potassium, extracted from a deposit located in the Brazilian Midwest, through geological characterization and agronomic evaluation through yield tests, soil and foliar potassium content. The tests were conducted in a greenhouse with seven treatments, two soil types and four replications, with millet, soybeans and beans in succession to evaluate the residual effect of the product. The agromineral was classified as a nepheline syenite saprolite with an average K2O content of 11.6%. The effects of the agromineral were promising, especially in the medium term. In the case of beans, at the standard dose of 60 K2O, yields in clay soils were 3.6 Mg ha-1 higher than in the 60 KCl treatment, which obtained only 2.3 Mg ha-1, probably due to absorption or leaching losses, since the effect evaluated was residual in nature. For all the crops evaluated, the agromineral showed an increase in potassium levels in both the soil and the leaves compared to the control group, indicating that it is a potential alternative to gradually reduce the use of traditional chemical fertilizers. Field trials are recommended to validate these benefits, taking into account more realistic environmental variations.

MITIGATION OF WATER DEFICIT STRESS IN WHEAT BY FOLIAR FEEDING OF POTASSIUM

An experiment was conducted at the research field of Crop Physiology and Ecology Department, Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur, Bangladesh during November 2021 to March 2022 to investigate the ameliorative effect of foliar application of potassium on wheat under non-irrigated water deficit stress condition, The treatments viz., well water (WW), water deficit stress (WDS) and foliar application of 2.23% K2SO4 under WDS were placed as main plot treatment and two wheat varieties (BARI Gom 28 and BARI Gom 32) were placed as sub plot treatment in split plot design following three replications. The interaction effect of growing conditions and wheat varieties significantly influenced the physiological traits, yield components and yield of wheat. Imposed water deficit stress significantly reduced different physiological traits, yield and yield attributes except proline content of flag leaf of wheat. Foliar application of potassium alleviated the adverse effect of water deficit stress in different degrees and improved the studied traits under stress condition. Foliar application of potassium was found more effective in BARI Gom 28 than that of BARI Gom 32. Foliar potassium increased grain yield by 7.43% and 3.56% in BARI Gom 28 and BARI Gom 32, respectively under water deficit stress condition. It can be concluded that additional foliar feeding of potassium along with recommended potassium could alleviate adverse effect of water deficit stress and improve productivity of wheat under drought environment.

Effect of Foliar Potassium on Maize Yield (Zea mays L.)

Field experiment was carried out during the 2018 growing season in the central Kut nursery located within the Kut district of the Wasit Province in Iraq, with four treatments and three replicates in a randomized complete block design (RCBD) to the response of maize to foliar application potassium irrigated by basin irrigation method. Foliar potassium spraying (K2O 43%) as follows; control (KO), 1000 (K1), 2000 (K2) and 3000 (K3) Mg.L−1. The study showed that there were substantial effects on the number of grains per row, the number of grains per ear, the grain yield, and the biological yield, with treatment K3 achieving the highest averages of (35.50, 554.5, 9.548 t. ha−1, and 25.97 t. ha−1) correspondingly. Although the weight of 500 grains and the harvest index were not significantly altered by treatment K2, while the number of rows per ear was (15.68), the number of rows per ear was.

Hyperspectral Imaging of Adaxial and Abaxial Leaf Surfaces for Rapid Assessment of Foliar Nutrient Concentrations in Hass Avocado

Rapid assessment tools are required for monitoring crop nutrient status and managing fertiliser applications in real time. Hyperspectral imaging has emerged as a promising assessment tool to manage crop nutrition. This study aimed to determine the potential of hyperspectral imaging for predicting foliar nutrient concentrations in avocado trees and establish whether imaging different sides of the leaves affects prediction accuracy. Hyperspectral images (400–1000 nm) were taken of both surfaces of leaves collected from Hass avocado trees 0, 6, 10 and 28 weeks after peak anthesis. Partial least squares regression (PLSR) models were developed to predict mineral nutrient concentrations using images from (a) abaxial surfaces, (b) adaxial surfaces and (c) combined images of both leaf surfaces. Modelling successfully predicted foliar nitrogen (RP2 = 0.60, RPD = 1.61), phosphorus (RP2 = 0.71, RPD = 1.90), aluminium (RP2 = 0.88, RPD = 2.91), boron (RP2 = 0.63, RPD = 1.67), calcium (RP2 = 0.88, RPD = 2.86), copper (RP2 = 0.86, RPD = 2.76), iron (RP2 = 0.81, RPD = 2.34), magnesium (RP2 = 0.87, RPD = 2.81), manganese (RP2 = 0.87, RPD = 2.76) and zinc (RP2 = 0.79, RPD = 2.21) concentrations from either the abaxial or adaxial surface. Foliar potassium concentrations were predicted successfully only from the adaxial surface (RP2 = 0.56, RPD = 1.54). Foliar sodium concentrations were predicted successfully (RP2 = 0.59, RPD = 1.58) only from the combined images of both surfaces. In conclusion, hyperspectral imaging showed great potential as a rapid assessment tool for monitoring the crop nutrition status of avocado trees, with adaxial surfaces being the most useful for predicting foliar nutrient concentrations.

Evaluation of the Efficiency of Foliar Potassium Applications as Drought Mitigation

Evaluation of the Efficiency of Foliar Potassium Applications as Drought Mitigation