What is potash?
- Potassium is the chemical element with the symbol K.
- Potassium salts such as carnallite, langbeinite, polyhalite, and sylvite form extensive deposits in ancient lake and seabeds
- K is necessary for the function of all living cells, and is thus present in all plant and animal tissues. It is found in especially high concentrations within plant cells, and in a mixed diet, it is most highly concentrated in fruits
- There is no natural or man-made substitute for potash
- Potash is mined from ore deep underground or extracted from brine by means of solution mining, and is milled on the surface
- Potassium Chloride (KCl) is the most widespread kind of potash fertilisers accounting for 95% of potash used as a fertiliser (muriate of potash)
K in Plants
Potassium participates in many physiological processes, such as growth, movement, transmission of signals, the upkeep of turgor pressure, and reproduction. Therefore potassium deficiency causes a variety of dysfunctions in plants’ metabolic processes, which can result in decreased productivity and quality of the crop yield.
- Soy plants growing in potassium-poor soils are often affected by potassium deficiency. First the margins of the leaves turn yellow, and then the yellowing spreads inwards. The centre and base of the leaf remain green
- If the deficiency is not addressed in time, chlorotic areas of the leaves extend into interveinal areas, giving the leaf a «fishbone» pattern
- Symptoms usually first appear on older leaves. If the deficiency is not addressed the leaf margins eventually die
- A number of visible symptoms can indicate Potash deficiency in rice, such as stunted plants with dark green leaves and short thin stems, rusty-brown spots that start at the tip and later spread over the entire area of the leaf, dry tips and margins of leaves, and a high percentage of rotten roots
- Under conditions of high temperature and low humidity, potash deficiency may cause premature senescence of older leaves and rolled-up younger leaves
- The lack of potassium can result in a high percentage of sterile or unfilled grains
- Symptoms of potassium deficiency in wheat crops first appear on lower leaves progressing towards the top as the severity of the deficiency progresses. A deficit of potassium results in discoloration of tips and margins of wheat leaves as they turn yellow and brown
- Lack of potassium in wheat often causes the weakening of the straw, which may result in lodging
- Leaves of maize plants suffering from potassium deficit turn yellow at tips and edges, then brown, then the discoloration affects the entire leaf and it dies. In sections, nodes are deep brown, different from internodes
- The growth of maize plants diminishes, roots stop their activity, stems weaken, and the plant is ready to fall down, when there is not sufficient amount of potassium in the plant organism
- The lack of potassium leads to malfunction of plant breathing, and the plant begins to use protein instead of carbohydrates. Nitrogen necessity of plant is tightly connected with potassium content: potassium deficiency stops nitrogen assimilation
- Potassium deficient plants soon show signs of wilting under dry conditions; grain formation is depressed and the tip of the ear may be without grain
- In plants the potassium ion is mobile. When it is deficient it tends to move from older leaves to newer ones, therefore the first visual symptoms of potassium deficiency can be identified by yellowish-white mottling of older leaves, which later changes to light yellowish-green. Leaves develop yellow spots between veins, their centres die, and numerous brown spots develop at tips and margins between veins. Tips and margins tend to curl downwards. Eventually, leaves become reddish-brown, dry out and fall off prematurely, cotton balls fail to develop properly and lint is of poor quality. Pic potash/p12В
Sugar cane 9%
- Older leaves of potassium-deficient plants are affected with chlorosis and necrotic lesions at their tips and along their margins. The upper surface of the midrib discolours to red.
Oil Palm 5%
- Lack of potassium in wheat causes reduction of harvest and degradation of the health of the plant
- Leaves develop yellow spots between veins, then become reddish-brown, dry out and fall off prematurely.
Fruits and vegetables
Fruits and vegetables
- Poor potash supply decreases the quality of the products while storing
- In case of potash deficit citruses have thick rind with decreased contents of citric and ascorbic acids in the juice
- Leaves of most vegetables dry out and fall off prematurely
- In plants the potassium ion is mobile. When it is deficient it tends to move from older leaves to newer ones, therefore the first visual symptoms of potassium deficiency can be identified by yellowish-white mottling of older leaves, which later changes to light yellowish-green. Leaves develop yellow spots between veins, their centres die, and numerous brown spots develop at tips and margins between veins. Tips and margins tend to curl downwards. Eventually, leaves become reddish-brown, dry out and fall off prematurely, in cotton the balls fail to develop properly and lint is of poor quality.
- Among the first visible symptoms of potassium deficiency in potato plants are reduced growth, reduced flowering, and bluish-green foliage. Over time, plant internocles become shortened, leaves bend downward and turn yellow, and eventually necrotic patches appear on their surface. The colour of potato crisps can be improved by potash fertilisers. Crisps made from potatoes grown using ample potash fertilisers are bright golden brown.
- Sunflower plants suffering from potassium deficit have thinner, more brittle stems. The deficiency of potassium reduces yield and oil content, as well as negatively affecting the ratio of unsaturated/saturated fat acids. Plant growth is significantly impeded by potassium-poor soils. Younger leaves of potassium-deficient sunflower plants form a rosette-like pattern and eventually develop dark brown necrotic patches. Ample application of potassium fertilisers may prevent these problems from occurring.
Potassium plays a great role in the plant participating in the following primary physiological processes:
Activates enzymes and promotes photosynthesis:
More than 60 enzymes have been shown to require potassium. Potassium rises the activity of amylase, invertase and proteolytic enzymes. Consequently, potassiumis responsible for synthesis of surose, starch and proteins, that leads to higher yields and better crop quality
- Expedites the flow of assimilates:
Assimilates are transported from leaves to storage organs or fruits. The flow of assimilates is faster when plants are well supplied with potassium
- Improves assimilation of nitrogen and facilitates synthesis of proteins:
Potassium doesn’t only increase the content of carbohydrates, but also changes the ratio among different groups, leading to transfer of monosaccharide to sucrose. Plants well supplied with potassium are able to take up more nitrogen and convert it more rapidly into protein
- Enhance the natural ability of plants to resist stress from drought and cold, pests and disease:
Potassium improves the ability to resist stress from cold in winter crops and perennial herbs. Potassium influences the quality of the products while storing. It is well known fact that root rot appears in the plants, that are not enough supplied with potassium. When there is a lack of potassium a sugar beet rots already in the field. Plants abundantly supplied with potassium can utilise soil moisture more efficiently than potassium-deficient plants
- Potassium facilitates the absorption of nitrogen, stimulating the translocation of amino-acids from vegetative shoots to the grain that promotes the synthesis of gluten and prolamines, as well as the formation of proteins that improve baking quality
- Potassium application increases the starch content of rice, wheat, soybean, sesame, and some other forage crops
- Potassium increases oil content in sesame, soybean, rape, groundnut, and cottonseeds
- Potassium increases protein and vitamin C content in potatoes. In addition, it increases the yield of large and medium-sized tubers and decreases weight loss in tubers after harvest. Potassium deficiency causes accumulation of reducing sugars and decreases starch content in potato tubers. Potato crisps made of such tubers are dark in colour
- Potassium increases the size of cotton balls, improves micronaire value and fibre strength, and increases the percentage of mature fibres
- In citruses, potassium positively affects rind thickness and improves fruit colour. It also enhances the contents of citric and ascorbic acids (vitamin C) in the juice and positively affects other juice characteristics such as the acid/sugar ratio and the content of soluble solids
- Potassium increases the amounts of solids, sugars, acids, and carotene in fruits and vegetables, and extends their shelf life
K and Environment
K is a natural chemical element that is among top-10 wide spread on the Earth.
- Potassium not absorbed by crop roots is absorbed by soil particles, which minimises the risk of potassium leaching. Potassium that penetrates deeper soil layers and reaches aquifers presents no ecological threat
- Potassium is not known to produce any harmful effect on the quality of natural and drinking waters and it does not induce eutrophication in rivers and lakes. But even when potassium is present in drinking water or food, it presents no hazard to human health
- Potassium fertilisers do not contain any of the heavy metals that are considered toxic and environmentally hazardous. Potassium fertilisers are not referred to as potential hazards in relation to radioactive elements
- Potassium fertilisers affect the environment positively. Potash fertilisers enable plants to utilise nitrogen fertilisers more effectively, so preventing nitrates from seeping through soil layers and mixing with surface and ground water reserves
- Potash fertilisers decrease the content of radioactive elements in food crops grown on contaminated land
K in Human Body
Potassium is vitally important for the normal functioning of the human organism:
- Potassium regulates water balance in the human body, normalises the heart rhythm, and influences the work of skin and kidneys
- Potassium is very important for normal work of nerve and muscle cells, transmission of nerve impulses
- The element is responsible for redox balance of blood and normalizes blood pressure. This is why some amount of potassium chloride is rarely used in table salt
- Potassium helps to supply the brains with oxygen, helps to get rid of waste products, helps to treat allergy
- Potassium can increase urine secretion, that is important when the organism is intoxicated
Potassium rich foods are potato, nettle, carrot, horse radish, cabbage, beetroot, onion, apple, grape, beans.