Potassium is not only one of the 16 nutrients necessary for crop growth and development, but also one of the three elements of fertilizer. Insufficient supply of potassium can affect quality, and severe potassium deficiency can also lead to reduced yield.
In the current agricultural production, due to the continuous increase in yield and multiple cropping index, the crop's demand for potassium increased correspondingly. In addition to the problem of insufficient supply of potassium in the southern soil, the soil with slightly higher potassium content in the north was affected by factors such as drought. It may also lead to potassium deficiency in high-yielding and hi-potassium crops. In recent years, nitrogen and phosphorus fertilizer consumption has been increasing year by year, especially driven by the leverage of current market price differentials. Nitrogen consumption will be a problem that will cause more nitrogen consumption, which will not only waste nitrogen fertilizer, increase environmental load, but also cause negative effects on crop yield and quality. . Therefore, here we must emphasize the importance of potassium and nitrogen and potassium nutrition balance.
Potassium contributes to the nutritive function of crops Potassium plays a major role in the crops as an activator for more than 60 enzymes. These enzymes are indispensable for the metabolism of crops, so potassium affects the growth, development, yield, and quality of crops extensively. Because sufficient supply of potassium is beneficial to the photosynthesis of crops, and the synthesis of starch and sugar is promoted, the starch and sugar content of potato, fiber, and sugar crops can be increased, and the sugar/acid ratio in fruits of fruits and vegetables can be improved. More suitable for people's tastes.
The availability of sufficient potassium for crops not only increases carbohydrate synthesis but also chain-linkedly increases nitrogen uptake by crops. Therefore, the nutrient balance between nitrogen and potassium should be balanced. Under the conditions of full supply of nitrogen fertilizer, attention must be paid to the balanced supply of potassium. Otherwise, the cereal crops are prone to lodging, and the quality of agricultural products is declining and storage is not tolerated. Potassium can increase the content of oils and proteins in crops, increase the content of crude fat and palmitic acid in peanut, rape, soybean and other oil crops, and increase the protein content of various crops. In leguminous crops, potassium can promote the nitrogen fixation of Rhizobium, which is reflected in the increase in the number of root nodules in legumes.
The nutritional effect of potassium is also manifested in that it can enhance the resistance of crops, including cold resistance, drought resistance, salt resistance, and acid resistance. Taking cold resistance as an example, if the grape buds are subjected to freezing injury, the application of potassium is less than half of the frozen buds without potassium application.
Potassium also enhances crop resistance to pests and diseases. Tests have shown that balanced potassium fertilizer can reduce rice leaf spot disease and rice blast disease; wheat scab; corn smut, large spot leaf blight; sweet potato scab, cotton wilt and citrus yellow rot disease; ; Tea plant anthracnose and other fungal diseases. The mechanism is that potassium can increase the metabolism of energy substances in crops, which is helpful for the development of the stratum corneum, the thickening of cell walls and the increase of cellulose content.
Balance of nitrogen and potassium can improve yield and quality. Under the premise of reasonable fertilization, potassium has a good effect in improving the quality of crop products, especially for economic crops. Therefore, some people in the production practice called potassium as a “quality elementâ€. In terms of cotton fiber crops, more potassium is needed. On the basis of reasonable application of nitrogen and phosphate fertilizers, proper application of potassium fertilizer is beneficial to the synthesis of cellulose, and increases the economic characteristics such as fiber length and strength. Similarly, in the hemp crops, potassium fertilizer can increase the hemp rate, hemp thickness, length and strength. Taking potato starch as an example, on the basis of nitrogen fertilizer, sufficient supply of potash fertilizer can promote the synthesis of starch in tubers, reduce the content of sugar and amino acids, and make the color of potato chips lighter, thereby improving the quality of its inner and outer appearance. .
In the fruit crops, the appropriate supply of potassium, improve the total sugar and reducing vitamin C content in fruits, improve the ratio of sugar to acid, increase fruit flavor. Especially when a large amount of nitrogenous fertilizer causes excess nitrogen in the body and adversely affects the fruit quality, sufficient potassium in the body can play a special role in repairing aphid. For example, when peach tree is used as an example, when nitrogen in the dendritic tree is excessive, due to The consumption of a large amount of carbohydrates hinders the formation of anthocyanins, resulting in poor coloration. When the potassium in the body increases and the proportion of nitrogen and potassium is appropriate, not only the fruit coloring is good, but also the sugar-acid ratio of the peach is improved, and timely ripening is promoted. The same effect is also reproduced on grapes and eggplants.
In the fertilization of food crops for super high-yield farmland, more attention should be paid to the balanced use of nitrogen and potassium fertilizers. Adequate potassium nutrition makes the stems of cereal crops thick and strong, increases in strength, improves mechanical properties, and is resistant to lodging and effective Impede the invasion of pathogenic pests. On the contrary, a large number of partial nitrogen fertilizers resulted in a disproportionate ratio of nitrogen and potassium. When there were few potassium nitrogen or significant potassium deficiency, the crop had a soft tissue structure, many soluble nitrogen compounds in the body, reduced crop resistance, and reduced high-yield security. Similarly, the structure of cotton leaves grown on potassium-depleted soil is loose, horniness is stunted, and more diseases and insect pests are infected.
Cao Yiping (Senior Advisor, Sinofert, Professor, China Agricultural University)
In the current agricultural production, due to the continuous increase in yield and multiple cropping index, the crop's demand for potassium increased correspondingly. In addition to the problem of insufficient supply of potassium in the southern soil, the soil with slightly higher potassium content in the north was affected by factors such as drought. It may also lead to potassium deficiency in high-yielding and hi-potassium crops. In recent years, nitrogen and phosphorus fertilizer consumption has been increasing year by year, especially driven by the leverage of current market price differentials. Nitrogen consumption will be a problem that will cause more nitrogen consumption, which will not only waste nitrogen fertilizer, increase environmental load, but also cause negative effects on crop yield and quality. . Therefore, here we must emphasize the importance of potassium and nitrogen and potassium nutrition balance.
Potassium contributes to the nutritive function of crops Potassium plays a major role in the crops as an activator for more than 60 enzymes. These enzymes are indispensable for the metabolism of crops, so potassium affects the growth, development, yield, and quality of crops extensively. Because sufficient supply of potassium is beneficial to the photosynthesis of crops, and the synthesis of starch and sugar is promoted, the starch and sugar content of potato, fiber, and sugar crops can be increased, and the sugar/acid ratio in fruits of fruits and vegetables can be improved. More suitable for people's tastes.
The availability of sufficient potassium for crops not only increases carbohydrate synthesis but also chain-linkedly increases nitrogen uptake by crops. Therefore, the nutrient balance between nitrogen and potassium should be balanced. Under the conditions of full supply of nitrogen fertilizer, attention must be paid to the balanced supply of potassium. Otherwise, the cereal crops are prone to lodging, and the quality of agricultural products is declining and storage is not tolerated. Potassium can increase the content of oils and proteins in crops, increase the content of crude fat and palmitic acid in peanut, rape, soybean and other oil crops, and increase the protein content of various crops. In leguminous crops, potassium can promote the nitrogen fixation of Rhizobium, which is reflected in the increase in the number of root nodules in legumes.
The nutritional effect of potassium is also manifested in that it can enhance the resistance of crops, including cold resistance, drought resistance, salt resistance, and acid resistance. Taking cold resistance as an example, if the grape buds are subjected to freezing injury, the application of potassium is less than half of the frozen buds without potassium application.
Potassium also enhances crop resistance to pests and diseases. Tests have shown that balanced potassium fertilizer can reduce rice leaf spot disease and rice blast disease; wheat scab; corn smut, large spot leaf blight; sweet potato scab, cotton wilt and citrus yellow rot disease; ; Tea plant anthracnose and other fungal diseases. The mechanism is that potassium can increase the metabolism of energy substances in crops, which is helpful for the development of the stratum corneum, the thickening of cell walls and the increase of cellulose content.
Balance of nitrogen and potassium can improve yield and quality. Under the premise of reasonable fertilization, potassium has a good effect in improving the quality of crop products, especially for economic crops. Therefore, some people in the production practice called potassium as a “quality elementâ€. In terms of cotton fiber crops, more potassium is needed. On the basis of reasonable application of nitrogen and phosphate fertilizers, proper application of potassium fertilizer is beneficial to the synthesis of cellulose, and increases the economic characteristics such as fiber length and strength. Similarly, in the hemp crops, potassium fertilizer can increase the hemp rate, hemp thickness, length and strength. Taking potato starch as an example, on the basis of nitrogen fertilizer, sufficient supply of potash fertilizer can promote the synthesis of starch in tubers, reduce the content of sugar and amino acids, and make the color of potato chips lighter, thereby improving the quality of its inner and outer appearance. .
In the fruit crops, the appropriate supply of potassium, improve the total sugar and reducing vitamin C content in fruits, improve the ratio of sugar to acid, increase fruit flavor. Especially when a large amount of nitrogenous fertilizer causes excess nitrogen in the body and adversely affects the fruit quality, sufficient potassium in the body can play a special role in repairing aphid. For example, when peach tree is used as an example, when nitrogen in the dendritic tree is excessive, due to The consumption of a large amount of carbohydrates hinders the formation of anthocyanins, resulting in poor coloration. When the potassium in the body increases and the proportion of nitrogen and potassium is appropriate, not only the fruit coloring is good, but also the sugar-acid ratio of the peach is improved, and timely ripening is promoted. The same effect is also reproduced on grapes and eggplants.
In the fertilization of food crops for super high-yield farmland, more attention should be paid to the balanced use of nitrogen and potassium fertilizers. Adequate potassium nutrition makes the stems of cereal crops thick and strong, increases in strength, improves mechanical properties, and is resistant to lodging and effective Impede the invasion of pathogenic pests. On the contrary, a large number of partial nitrogen fertilizers resulted in a disproportionate ratio of nitrogen and potassium. When there were few potassium nitrogen or significant potassium deficiency, the crop had a soft tissue structure, many soluble nitrogen compounds in the body, reduced crop resistance, and reduced high-yield security. Similarly, the structure of cotton leaves grown on potassium-depleted soil is loose, horniness is stunted, and more diseases and insect pests are infected.
Cao Yiping (Senior Advisor, Sinofert, Professor, China Agricultural University)