Foliar fertilization is an effective method of increasing the quality of crops and crop efficiency. However, it cannot be treated as the only way to fertilize. When using foliar feeding, it should be remembered that the efficiency of nutrient uptake will be better if proper agrotechnics are followed in plant cultivation. We are talking about a situation where the pH of the soil is regulated and its abundance in phosphorus, potassium and magnesium is at least at an average level, and when basic soil fertilization with NPK was performed.
Foliar feeding with fertilizers is of great importance for arable crops because it:
Plants respond best to foliar feeding in the initial phase of growth. Older parts of plants also respond to foliar fertilization, but unlike young parts, they are covered with a thicker layer of wax, which reduces liquid absorption.
When applying foliar feeding, it must be remembered that each crop is associated with a separate need for nutrients necessary to produce a crop at the desired level. For this reason, the best foliar fertilizer should be dedicated to each crop separately.
It is worth noting that cereals with a yield of 1t of grain and an appropriate mass of straw take up:
N-30 kg,P2O5-12kg,K2O-22kg, CaO-6kg,MgO-5kg,S-4kg,B-6g,Cu-9g,Fe-250-360g,Mn-70-120g,Mo-0,8g,Zn-60-95g.
By foliar feeding the cereals with microelements, it is possible to cover the entire requirement for these nutrients. Manganese, copper and zinc have a positive effect on the nitrogen balance of plants, stimulate the uptake and processing of this nutrient, as well as the development of the root system itself.
Copper - reduces the susceptibility to lodging, increases the number of grains in the ear, and regenerates the tissues damaged by frost. A deficiency of this element increases the susceptibility to lodging. It causes bleaching and drying of the ears and a disease of the early plants (whitening of the ends of the leaves) and leads to poor heading and, consequently, to a reduction in yield.
Manganese - strengthens the frost resistance of plants, intensifies photosynthesis, and increases resistance to diseases of the stem base. Manganese deficiency causes inhibition of plant growth, gray blotch of cereals and numerous chlorosis and necroses on the leaves.
As can be seen from the above list, the importance of copper and manganese in the cultivation of cereals cannot be overestimated. Only proper plant nutrition with these ingredients can ensure good foliar fertilization with other nutrients (including nitrogen and phosphorus), and thus high grain yields of good technological quality.
Fertilizing cereals with microelements should be carried out from the tillering phase to the beginning of the shooting. Depending on the needs and possibilities, we perform two or three treatments, combining them with plant protection products - fungicides and insecticides.
Corn with the yield of 1t of grain and the appropriate weight of straw takes:
The most important micronutrients in maize cultivation are zinc, boron, manganese, iron and also copper. It is worth remembering that in practice, this plant requires prophylactic foliar fertilization with all the mentioned microelements.
Zinc - is involved in all major functions in the plant. Therefore, good nutrition of plants with this ingredient is one of the necessary conditions for them to be able to yield high. Zinc intensifies nitrogen transformation in the plant, increases resistance to drought and diseases, increases the biological quality of the grain and influences the synthesis of chlorophyll. A deficiency of this element causes plant dwarfism, delayed panicle ejection and flowering, reduced leaf surface and a light green color between the veins on young plants. In addition, wide white discolored bands appear on both sides of the medial nerve, starting at the base of the leaf but not reaching the top of the leaf (the middle nerve and leaf edges remain green).
Boron - is the second very important micronutrient in corn fertilization. Specific symptoms of malnutrition with boron in maize are only revealed in extreme malnutrition. In practice, latent deficiencies are the most common. Boron plays an important role in the metabolism of carbohydrates and stimulates the development of generative organs. It significantly influences pollen germination and pollen tube growth. It also participates in the formation of cell wall structures, making plants less susceptible to lodging. Boron malnutrition strongly inhibits maize growth and causes disturbances in flowering. As a consequence, the cobs are smaller and poorly filled, and the grains are poorly formed, of various sizes, embedded in irregular rows (so-called cobs or button-like shapes).
Manganese - intensifies photosynthesis, improves plant vigor, increases resistance to diseases, affects the uptake of phosphorus from the soil. It is indispensable in soils with a pH above 6.5. A deficiency of this element causes marbling of the leaves, small leaf veins are green and the spaces between them turn yellow.
Rapeseed with the yield of 1t of seeds and the appropriate weight of straw and roots takes up:
Foliar feeding of oilseed rape should be treated as basic in the case of micronutrients, because in this way it is possible to cover the entire demand of rape for these ingredients.
Boron - is the most important among all micronutrients. Its deficiency in autumn causes weaker development of the root system, and therefore worse overwintering and lower yields. Boron thickens cell juices in autumn, thus supporting the overwintering of rapeseed, and in spring it supports the growth of root cells and the uptake of potassium and phosphorus. In spring, boron also improves the process of flowering, pollination and fertilization, rapeseed water management, as well as transpiration and respiration. The deficiency of this element causes the reduction of inflorescences, a smaller number of pods on the plant and fewer seeds in the shell. The susceptibility to diseases increases, frost resistance is lowered and the stems break.
Manganese - is responsible for the synthesis of chlorophyll and carbohydrates and for stimulating the growth of new cells. In addition, Manganese has a positive effect on the development of side roots, improves their health and stimulates the uptake of phosphorus and iron from the soil. A deficiency of this element results in growth inhibition, less disease resistance, fewer pods and a reduction in seed fat.
The first foliar fertilization of rapeseed - with micro and macro elements - is performed in the fall. Boron, manganese, copper, molybdenum, zinc and iron are a whole range of micronutrients necessary in foliar fertilization, because when properly dosed they cover the entire rape requirement for these ingredients. If possible, it is also best to combine them with insecticide and/or fungicide protection. The first spring treatment is performed in the rosette phase (plants should have an assimilation apparatus), while the second one in the green bud phase. Performing several treatments spreading them over time is important especially in the case of boron, because it does not move well in plants.
Sugarbeet - with a yield of 1t of roots and an appropriate mass of leaves takes:
Sugarbeet is one of the plants with high nutritional needs. Of all the nutrients, foliar nutrition with micronutrients should be treated as complete, because the foliar feeding can cover the entire demand of beet for these nutrients.
Boron - is very important in foliar fertilization of beetroot and is responsible for the transport of sugars from the leaves to the root, and also increases the frost resistance of plants. A deficiency of this element causes dry root rot, heart leaf gangrene, as well as cracking and small leaves.
Manganese - is responsible for nitrogen management of plants and intensifies photosynthesis. The deficiency of this element is manifested in the first place by brightening on the leaves in the form of marbling between the leaf veins. The leaves may curl upwards and even die in the middle of the leaf blade. Manganese deficiency also reduces the content of simple sugars.
Sodium - affects the efficiency of photosynthesis, plant hydration, root growth and an increase in the yield of technological sugar.
Zinc - a typical symptom may be beetroot leaf bleaching, generally stunted growth, leaf dwarfism.
Molybdenum - characteristic elongation of the petioles, one-sided (sometimes bilateral) underdevelopment of the leaf blade and leaf narrowing.
Micronutrient spraying should be carried out from the 4-6 leaf stage to the full row coverage stage. The sooner we spray the first time, the better. Most often, beetroot is fertilized with microelements using two or three sprays, and it is best to keep at least 10 days between sprayings.
The decision to choose a fertilizer should be preceded by determining the plant's need for micro-nutrients. Anticipating their shortage or shortage, it is absolutely necessary to supplement them. They fulfill the above-mentioned essential physiological functions.
When choosing a foliar fertilizer, we should be guided by the following parameters:
If you want to learn more about foliar fertilizers, we encourage you to read our article https://www.dr-green.pl/nawozy-dolistne.