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The importance of potassium management for horticultural crops
... One critical factor affecting onion bulb yield is the availability of nutrients (Khokhar, 2019). Potassium (K) is well-recognized as a vital nutrient for vegetable crops growth (Mikkelsen, 2017). K is a major plant nutrient required in substantial amounts, primarily supplied through fertilizers (Manning, 2010). ...
The optimizing management practices including optimum potassium use and mulching approaches are pre-requisite for profitable onion production. The research study was carried out at the Onion Research Institute Husri, Hyderabad, Agricultural Research Center Tandojam aimed to evaluate the integrated use of potassium and mulching on onion growth and yield. The experiment, which involved the nasarpuri onion variety, followed a three-replicated randomized complete block design (RCBD) with a factorial arrangement. The treatment details were as follows: Factor A represented potassium rates (kg K₂O ha⁻¹) (K₁= Control, K₂= 40, K₃= 50, and K₄= 60), and Factor B represented mulching (M₁= Without mulching and M₂= With mulching). Data were collected for various parameters, including plant height, stem girth, bulb diameter, bulb weight, leaf weight, bulb yield, and potassium content in leaves and bulbs. The findings showed that plant height ranged from 33.17 to 44.80 cm, stem girth from 6.79 to 14.10 cm, bulb diameter from 45.17 to 67.00 cm, bulb weight from 10,796 to 29,126 kg ha⁻¹, leaf weight from 1,610 to 4,353 kg ha⁻¹, and the number of leaves per plant varied from 7.20 to 13.15. Additionally, potassium content in leaves ranged from 1.50% to 1.86%, and potassium content in bulbs varied from 1.14% to 1.35%. Notably, the combination of 60 kg K₂O ha⁻¹ with mulching resulted in the most favorable outcomes across various parameters. These results emphasize the importance of integrated potassium management and mulching techniques in enhancing onion growth, yield, and potassium uptake
... Using K as an example, when adequate K is provided, the harvest quality of crops such as banana, potatoes, cotton, citrus, etc. is improved. Vitamin C concentrations are enhanced with an adequate K supply, physiological disorders of citrus and tomatoes are reduced, nutraceutical compounds (such as lycopene) are increased, shelf life is extended, and disease and insect resistance are boosted (Mikkelsen, 2017). ...
The 20th century saw the development of a highly efficient nutrient industry producing affordable fertilizers that contributed greatly to increased food, feed, fiber, and fuel production for a growing global population. Plant nutrient production and use in the 21st century faces pressure to improve efficiency and outcomes. The nutrient industry has historically operated with large volumes and low margins, and has, at times, been slow to embrace innovations. However, the landscape has changed, driven by the demand for superior products, practices, and environmental stewardship. This transition marks the advent of what experts term “responsible plant nutrition” (International Fertilizer Association, 2024). This is the third and final article in a series on the past, present, and future of the North American fertilizer industry. Earn 1.5 CEUs in Nutrient Management by reading this article and taking the quiz at https://web.sciencesocieties.org/Learning‐Center/Courses .
... Potassium is an essential macronutrient that assist in plant growth and development, performing several physiological functions, including the maintenance of cellular osmotic pressure, improvement of photosynthetic assimilation and nutrient absorption, and assistance in transporting water by controlling stomatal opening and closing (Prajapati & Modi, 2012;Etesami, Emami & Alikhani, 2017;Hu et al., 2016;Sardans & Peñuelas, 2021). It also contributed to the activation of several enzymes in plants and animals that are responsible for energy metabolism, starch synthesis, nitrate reduction, photosynthesis, and sugar degradation (Almeida et al., 2015;Mikkelsen, 2017;Souto et al., 2018;Kumar et al., 2020). Potassium deficiency can reduce photosynthetic CO2 fixation and the transport and use of assimilates, cause membrane and chlorophyll degradation, and hinder cell wall synthesis and cell turgor, making plants susceptible to lodging when subjected to strong winds, rain, or excessive nitrogen fertilization. ...
Purpose: To present the benefits of increasing oat sowing density on productivity, uniformity, soil quality and reduction of pesticides and the use of an organomineral product based on calcium and potassium as an alternative to lodging control, promoting more sustainable cultivation systems. Theoretical framework: Increasing plant density can promote productivity, rapid soil coverage, reduction of weeds and greater harvest uniformity, reducing the use of pesticides. However, increasing seeding density can promote lodging. Lodging is the phenomenon in which plants leave the vertical position and fall to the ground, affecting the quality of the grains. The commercial product registered to control lodging is highly toxic to the environment. Organomineral sources with potassium and calcium represent an alternative for controlling lodging with reduced environmental impacts. Results: Benefits of increased seeding density to promote grain yield have been found for several crop species, reinforcing the need for adapting seeding density for oat crops. The use trinexapac-ethyl as a growth regulator, it poses risks of phytotoxicity and environmental contamination. In this context, several studies have indicated that potassium and calcium favor cell wall rigidity, potentially contributing to oat stem strength. Originality/value: This study provides significant contribution to the advancement of research on oat in Brazil, bringing new information benefiting farmers, technical assistance agents, and the food industry and improving the production system to ensure food security and care for the environment.
... Hence, K is often referred as most important quality element for fruit growth and post-harvest quality formation (Usherwood, 1985;Wu et al., 2021). K also plays a vital role in various essential plant functions, such as enzyme activation (Prajapati and Modi, 2012), photosynthesis (Tränkner et al., 2018), carbohydrate metabolism (Mikkelsen, 2017), the control of stomatal activity and transpiration through osmotic regulation (Cochrane and Cochrane, 2009), growth and development (Jung et al., 2009), and the response to abiotic stresses (Araujo et al., 2015). K uptake in plants begins with absorption through root cells, followed by transportation through xylem cells to leaves and fruit (Brown and Cartwright, 1953). ...
Essential macronutrients, including nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S), significantly contribute to plant growth and developmental processes. The occurrence of nutritional stress, particularly the inadequate application of essential macronutrients, leads to the manifestation of numerous deficiency symptoms because of suboptimal nutrients supply. The utilization of visual deficiency symptoms has been widely employed in the field of plant nutrition for the purpose of assessing the nutritional status and optimizing the efficacy of fertilizer application. Hence, it is imperative to comprehend the morphological , physiological, and molecular changes exhibited by fruit trees in response to nutrient stress. This review discussed to establish a comprehensive connection between the visual phenotypic deficiency symptoms and the underlying molecular and physiological responses correlated with macronutrient dynamics in fruit trees. we proposed a range of nutrient management strategies, including integrated nutrient management and the principles of the 4 R's (right source, right rate, right time, and right place) that can be supportive for better plant growth and optimized production under nutrients stress environment. We also explored the significant contribution of advanced molecular tools such as omics tools (genomics, transcriptomics, proteomics, metabolomics, and ionomics) and automatized technologies (imaging technology, remote sensing, and in-field sensors). These advancements are integral to integrated nutrient management, as these can be harnessed for improving fruit tree nutrition and promoting sustainability in orchard systems. These recent advancements underlying plant responses to nutrients deficiencies offer an invaluable opportunity for a deeper understanding of macronutrients functionality in fruit trees.
... Potassium is also reported to be responsible for the transport of sugars, synthesis of starch and proteins, transportation of water and nutrients in the plant system. It also helps in the enhancement of crop quality and extends the shelf life of fruits and vegetables [44][45][46][47]. ...
... Adequate K supply generally increases the firmness and strength of skin, allowing greater resistance to damage during transport and storage. The positive impact of K on fruit storage has been reported on many crops, including bananas (shelf-life), citrus (Citrus spp.) (Decreased post-harvest mold and rot), potatoes (storage longevity), carrots (Daucus carota) (crispness), pineapple (greater vitamin C leading to reduced browning and rot), figs (Ficus carica), and apples (Mikkelsen, 2018). Potassium is essential for sustaining both the yield and the quality of many horticultural crops. ...
Almost one-fourth of the global population live in South Asia (SA) countries with 14% of cultivable land. Most of the countries in the South Asian region are facing multiple challenges like high population growth, declining farm land area, and low productivity in primary and secondary sectors leading to limited employment opportunities. Consequently, both availability and access to food are adversely affected. Regions exposed to natural disasters, tribal and the hilly regions of SA are amongst the most vulnerable in terms of food security. Accelerated efforts are required to ensure that conflicts do not exacerbate the already fragile food situation in SA. Despite recent strong gains in economic growth and agricultural productivity, food and nutritional security remains a major concern in SA. The region has the largest concentration of poverty and hunger in the world, with nearly 40% of the world's impoverished and 45% of the world's undernourished people. The enormity of malnutrition in SA can be gauged from the fact that it is the home to nearly two-thirds of the world's undernourished children. More than 56% of the world's low-birth-weight babies are born in SA. Furthermore, food and nutrition security remain major challenges with a large proportion of the world's poor living here and global hunger index (GHI) at 30.9. Overcoming these twin challenges require actions both at the national and regional level.
Among production constraints and yield gaps, imbalanced nutrient use is a critical issue in many of the SA countries, with nutrient application focused mainly on nitrogen (N), leaving the possibility for other plant nutrient deficiencies including phosphorus (P) and potassium (K). In some cases, the use efficiency of N may be low due to losses in the form of N2O emissions, a potent greenhouse gas (GHG), or via leaching with the undesirable offsite effects. Among the primary nutrients, K is an essential nutrient for productivity, food quality and numerous functions in the plant system. It plays a major role in activating ∼60 enzymes, regulating stomatal functions, controlling water relations especially under rainfed crop production, influencing the water balance of plant systems, and underpinning agronomic productivity and sustainability. Negative K balance in soil under intensive cropping is reported because of low external input and large crop removal, leading to large scale K mining in soils. Declining yield trends were observed in several fertilizer experiments 30–40 years long with continuous application of either N alone or NP without K under both irrigated and rainfed crop production systems in the region. Recent K fertility analysis indicates widespread K deficiency in light-textured alluvial soils, red and lateritic soils beside acid soil types in India, Bangladesh, Sri Lanka, and Pakistan. The countries in SA depend largely on imported K fertilizers. Such imported fertilizer should be utilized most efficiently in the light of limited global K mineral reserves and 93% of world total K exports are from five countries viz. Canada (37.12%) followed by the Russian Federation, Belarus, Germany and Israel.
Therefore, the current review addresses issues related to the K supplying capacity of soils in various crop production systems in SA, crop K responses, soil test methods followed, emerging issues in soil K fertility, K balance in major cropping systems and rationalizing K recommendations among crops, soil types and agro-ecological regions. The role of K in balanced nutrition, farm productivity, food and nutritional security in these countries is examined. The review also covers the critical role of K in climate change adaptation, mitigation of nitrous oxide (N2O) emissions and improving overall nitrogen use efficiency (NUE) in the SA region.
... Adequate K supply generally increases the firmness and strength of skin, allowing greater resistance to damage during transport and storage. The positive impact of K on fruit storage has been reported on many crops, including bananas (shelf-life), citrus (Citrus spp.) (Decreased post-harvest mold and rot), potatoes (storage longevity), carrots (Daucus carota) (crispness), pineapple (greater vitamin C leading to reduced browning and rot), figs (Ficus carica), and apples (Mikkelsen, 2018). Potassium is essential for sustaining both the yield and the quality of many horticultural crops. ...
... Adequate K supply generally increases the firmness and strength of skin, allowing greater resistance to damage during transport and storage. The positive impact of K on fruit storage has been reported on many crops, including bananas (shelf-life), citrus (Citrus spp.) (Decreased post-harvest mold and rot), potatoes (storage longevity), carrots (Daucus carota) (crispness), pineapple (greater vitamin C leading to reduced browning and rot), figs (Ficus carica), and apples (Mikkelsen, 2018). Potassium is essential for sustaining both the yield and the quality of many horticultural crops. ...
Rice is the third largest crop produced worldwide, the majority of which is flood irrigated and accounts for about one-third of the global irrigated area. Relative to other crops, rice requires a large amount of scarce water input. Research has shown that irrigated rice water use can be substantially reduced by decreasing the period of permanent flooding through water saving irrigation techniques. For regions where irrigation water can be controlled, increased labour demand, weed and pest infestation and risk of water stress are major inhibiting factors for widescale adoption of water saving rice. Automation of irrigation has the potential to resolve some of these issues. Automated irrigation has long been commercially practised in pressurized systems and proven to save significant labor; however, it has not been adopted in gravity surface irrigation systems.
The purpose of this chapter is to review the current status of automated gravity surface irrigation in rice, identify potential technical adoption-limiting factors of the few previously developed systems and outline additional functionality required of an automated irrigation system for water savings in commercial scale rice systems during both ponded and non-ponded periods. To harness the full economic, social and environmental benefits that automation could provide, research is required to determine the most appropriate parameters to schedule irrigation during non-ponded periods and regionally and varietal specific thresholds. Resolution of the research and technical gaps outlined in this chapter could enable widescale adoption of irrigation practice that significantly reduce irrigation water input whilst simultaneously reducing paddy GHG emissions.
... Aliado a isso, o potássio que também tem função no controle de doenças se caracteriza como um macronutriente essencial para o crescimento das plantas, apresentando inúmeras funções fisiológicas, incluindo a manutenção da pressão osmótica celular, a melhora da assimilação fotossintética e da absorção de nutrientes, além de auxiliar no transporte de água através do controle da abertura e fechamento dos estômatos (Prajapati & Modi, 2012;Etesami et al., 2017;Hu, et al., 2020;Sardans & Peñuelas, 2021). Este elemento recebe destaque por aumentar a resistência das plantas a doenças, pragas e estresses abióticos, auxiliando na ativação de inúmeras enzimas responsáveis por processos vegetais e animais, como metabolismo energético, síntese de amido, redução de nitrato, fotossíntese e degradação de açúcar (Almeida, et al., 2015;Mikkelsen, 2017;Souto, et al., 2018;Kumar, et al., 2020). ...
White oat is a winter species with numerous benefits to cultivation systems and animal and human nutrition. It is
recognized as a nutraceutical food for its health benefits. This condition has promoted the increase of cultivation areas
seeking to meet the demand, however, favoring the emergence of fungal diseases, responsible for expressive damages
in the productivity and quality of grains. Leaf rust (Puccinia coronata f. sp avenae) and helminthosporiose
(Drechslera avenae (Eidam) Sarif) are the most relevant due to their aggressiveness. These diseases are not
satisfactorily controlled by genetic resistance and their occurrence and aggressiveness is related to the presence of a
favorable environment for the development of fungi, a susceptible host, and a virulent pathogen. The use of fungicide
has been the most efficient alternative of control, in the guarantee of productivity with economic return to the farmer.
However, the use of pesticides has generated discussions about the adverse effects on the environment, food safety
and public health, a condition that reinforces the search for more sustainable agricultural systems. This review seeks
to present a deep discussion about pesticides and more sustainable alternatives that can reduce and/or avoid the
incidence and severity of fungal diseases in oats. Among the alternatives, the discussion encompasses two potential
management technologies, sowing involving escape zones to restrict the development of fungi and the use of abiotic
resistance inducers by silicon and potassium.
Keywords: Avena sativa L.; Functional food; Zoning; Food security; Agenda 2030.
An adequate potassium (K) supply is essential for both organic and conventional crop production. Potassium is involved in many plant physiological reactions, including osmoregulation, protein synthesis, enzyme activation, and photosynthate translocation. The K balance on many farms is negative, where more K is removed in harvested crops than is returned to the soil. Although various organic certification agencies have different regulations governing allowable sources of K, the behavior of soil K is largely governed by its solubility. The slow release of K from soil minerals is often insufficient to meet the peak nutrient demand of high-yielding crops, but they can contribute to the long-term improvement of soil fertility. There are many excellent K sources allowed for organic crop production, including soluble minerals such as langbeinite, sylvinite, and potassium sulfate. Potassium sources such as wood ash, greensand, and seaweed can also supply K but require special management because of their low nutrient content, their effect on soil pH, low solubility, or bulky nature. The concentration of Kin manures and composts is highly variable, but it is generally quite soluble and available for plant uptake. Some rock minerals may supply a portion of the K requirement of plants, but many are too insoluble to be of practical significance.
The effect of K fertigation through subsurface irrigation lines on processing tomato (Lycopersicon esculentum Mill.) fruit yield and quality was evaluated in four field trials in California from 2002–04. Fields had exchangeable soil K between 0.48 to 0.85 cmol·kg–1, with high exchangeable Mg (10.6 to 13.7 cmol·kg–1) and a history of yellow shoulder (YS, a fruit color disorder) occurrence. K treatments evaluated included seasonal amount applied (0 to 800 kg·ha–1), fertigation method (continuous versus weekly), and timing (early, mid or late season); foliar K treatments were also included in the 2002 trial. In two fields total and marketable fruit yield were significantly increased by K fertigation, and fruit color improvements were observed in all trials. Among color parameters improved by K fertigation were YS incidence, blended color, and L*, chroma, and hue of the shoulder region of fruit. K fertigation did not affect fruit soluble solids concentration. Yield increased only with fertigation treatments initiated during early fruit set. The effects of fertigation method and rate were inconsistent. Foliar K application was ineffective in increasing either fruit yield or quality.
Potassium appears to have profound influence on fruit quality through its influence on size, appearance, colour, soluble solids, acidity and vitamin contents. Potassium deficiency in fruits is often observed even in K-rich soils. Fruits like banana, grapes, peach and passion fruit have high potassium requirement. Although potassium does not form part of the structure of plant constituents, it regulates many vital functions like carbon assimilation, translocation of proteins and sugars, water balance in plants, maintaining turgor pressure in the ceD, root development, improving quality of . the fruits by maintaining desirable sugar to acid ratio, ripening of fruit and many other processes. Thus, It is the most important nutrient regulating the quality of fruits. Potassium is involved in many aspects of plant physiology viz., activation Gf more than 60 enzymes, aiding in photosynthesis, favouring high energy status, regulation of stomata opening etc. With the changing cropping pattern, need for potassium nutrition has become pertinent to obtain high yield of quality fruits. In this review paper role of potassium on various physiological processes in improving the yield and quality of major fruit crops has been discussed. All fruit crops have strict requirement for a balanced fertilizer management, Many horticultural crops are heavy removers of nutrients and high yields can only be sustained through the application of optima) doses in balanced proportion. Among the major nutrients, potassium not only improves yields but also benefits various a~pects of quality. Hence, potassium fertilization results in a higher value product and thetefore ina greater return to the farmer. . What is Potassium? Potassium is one of the essential nutrients for plant growth and vital for sustaining high-yield in agriculture. Potassium is often referred as the quality element for crop production (Usherwood, 1985), The crucial importance of potassium in quality formation stems from its role in promoting synthesis of photosynthates and their transport to fruits, grains;« tubers, and storage organs and to" enhance their conversion into starch, protein, vitamins, oil etc. (Mengel and Kirkby, 1987). With d shortage of potassium many metabolic processes are affected, like the rate of photosynthesis, the rate of translocation and enzyme systems (Marschner, 1995; Mengel, 1997). At the same time, the rate of dark respiration is increased. The result is a reduction in plant growth and in crop quality.
Potassium was identified as a shortfall nutrient by the Dietary Guidelines for Americans 2010 Advisory Committee. The committee concluded that there was a moderate body of evidence of the association between potassium intake and blood pressure reduction in adults, which in turn influences the risk of stroke and coronary heart disease. Evidence is also accumulating of the protective effect of adequate dietary potassium on age-related bone loss and reduction of kidney stones. These benefits depend on organic anions associated with potassium as occurs in foods such as fruits and vegetables, in contrast to similar blood pressure-lowering benefits of potassium chloride. Benefits to blood pressure and bone health may occur at levels below current recommendations for potassium intake, especially from diet, but dose-response trials are needed to confirm this. Nevertheless, intakes considerably above current levels are needed for optimal health, and studies evaluating small increases in fruit and vegetable intake on bone and heart outcomes for short periods have had disappointing results. In modern societies, Western diets have led to a decrease in potassium intake with reduced consumption of fruits and vegetables with a concomitant increase in sodium consumption through increased consumption of processed foods. Consumption of white vegetables is associated with decreased risk of stroke, possibly related to their high potassium content. Potatoes are the highest source of dietary potassium, but the addition of salt should be limited. Low potassium-to-sodium intake ratios are more strongly related to cardiovascular disease risk than either nutrient alone. This relationship deserves further attention for multiple target tissue endpoints.
Agricultural production continues to be constrained by a number of biotic and abiotic factors that can reduce crop yield quantity and quality. Potassium (K) is an essential nutrient that affects most of the biochemical and physiological processes that influence plant growth and metabolism. It also contributes to the survival of plants exposed to various biotic and abiotic stresses. The following review focuses on the emerging role of K in defending against a number of biotic and abiotic stresses, including diseases, pests, drought, salinity, cold and frost and waterlogging. The availability of K and its effects on plant growth, anatomy, morphology and plant metabolism are discussed. The physiological and molecular mechanisms of K function in plant stress resistance are reviewed. This article also evaluates the potential for improving plant stress resistance by modifying K fertilizer inputs and highlights the future needs for research about the role of K in agriculture.
Among the many plant mineral nutrients, potassium (K) stands out as a cation having the strongest influence on quality attributes that determine fruit marketability, consumer preference, and the concentration of critically important human-health associated phytonutrients. However, many plant, soil, and environmental factors often limit adequate uptake of K from the soil in sufficient amounts to satisfy fruit K requirements during development to optimize the aforementioned quality attributes. The objectives of this review are 1) to summarize published study abstracts on the effects of soil and/or foliar K fertilization as well as diverse K forms, on fruit phytonutrient concentrations; and 2) to illustrate the important role of K forms on fruit quality with a case study of Cucumis melo L (muskmelon) fruit produced with optimal soil applied K . The muskmelon studies will compare commercial sources (forms) of K applied to examine seasonal effects (spring vs. autumn) and the number of foliar K applications during fruit development on fruit marketability (maturity, yield, firmness, soluble solids, sugars, relative sweetness), consumer preference attributes (sugar content, sweetness, texture), and phytochemical concentrations (K, ascorbic acid, and β-carotene concentrations). Numerous studies have consistently demonstrated that specific K fertilizer forms, in combination with specific application regimes, can improve fruit quality attributes. Potassium fertilizer forms in order of effectiveness (Glycine (Gly)-complexed K = K₂SO₄ ≥ KCl > no K > KNO₃) when applied wet (foliar or hydroponic) vs. dry (soil) were generally superior in improving fruit marketability attributes, along with many human-health nutrients. The muskmelon case study demonstrated that two K forms: Gly-complexed K and K₂SO₄, combined with a silicone-based surfactant, applied weekly, as a foliar spray, during fruit development, from both autumn and spring-grown plants, had the greatest impact on improving fruit marketability attributes (maturity, yield, firmness, and sugars), as well as fruit quality attributes (human-health bioactive compounds K, ascorbic acid, and β-carotene). Among several foliar applied K salts studied under field conditions so far, salts with relatively low salt indices appeared to have the greatest impacts on fruit quality when applied during the mid- to late-season fruit development periods.
Three kinds of evidence point toward declines of some nutrients in fruits and vegetables available in the United States and the United Kingdom: 1) early studies of fertilization found inverse relationships between crop yield and mineral concentrations—the widely cited ''dilution effect''; 2) three recent studies of historical food composition data found apparent median declines of 5% to 40% or more in some minerals in groups of vegetables and perhaps fruits; one study also evaluated vitamins and protein with similar results; and 3) recent side-by-side plantings of low- and high-yield cultivars of broccoli and grains found consistently negative correlations between yield and concentrations of minerals and protein, a newly recognized genetic dilution effect. Studies of historical food composition data are inherently limited, but the other methodscanfocusonsingle cropsofanykind, canincludeanynutrientofinterest, andcanbecarefullycontrolled. Theycan also test proposed methods to minimize or overcome the diluting effects of yield whether by environmental means or by plant breeding. This article summarizes three kinds of evidence pointing toward declines during the last 50 to 100 years in the concentration of some nutrients in vegetables and perhaps also in fruits available in the United States and the United Kingdom.
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International Potash Institute,
Horgen, Switzerland.