Low potassium fertilizer application rates lead to reduced crop yields
Foliar feeding is a fertilization method in which a diluted solution of chemical fertilizers or trace elements is sprayed onto the leaves and absorbed and utilized by the plant through the leaf stomata, so it is also called topdressing outside the roots. The advantages of topdressing outside the roots are: small dosage, rapid and significant fertilizer effect, the fertilizer is not fixed by the soil and is not affected by the absorption function of the root system...
At present, the input of chemical fertilizers in agricultural production has achieved remarkable results, but there is still irrationality, and there is still great room for the development of scientific fertilization. The most prominent issue is the irrational ratio of nitrogen, phosphorus and potassium fertilizer application.Crops have a relatively large demand for nitrogen, phosphorus and potassium. The ratio of chemical fertilizer nitrogen, phosphorus and potassium is 1:0.39:0.22. The nitrogen-to-phosphorus ratio is tending toward reasonable, but the proportion of potassium fertilizer is too low, and most farmers do not even know that crops need potassium fertilizer. At present, the use of organic fertilizers, especially farmyard manure, has decreased, leading to a serious potassium deficiency in farmland. According to the law of the minimum nutrient, crop yield is determined by the effective plant growth factor with the relatively smallest content in the soil. Therefore, in the case of potassium deficiency, excessive application of nitrogen fertilizer and phosphorus fertilizer cannot increase yield, and on the contrary will increase agricultural production costs and cause soil pollution.
Different crops require different proportions of the three elements nitrogen, phosphorus and potassium. Under general fertility conditions, the demand of crops for potassium is at the same level as that for nitrogen, and may even be greater than that for nitrogen (such as potatoes). At present, the neglect of potassium fertilizer application in agricultural production not only reduces yield, but also increases production costs due to the excessive application of other fertilizers, affecting income and reducing farmers' enthusiasm for production.