Winter wheat was and remains the most important grain crop of Ukraine. To get a good harvest, the landowner must:
Growing winter wheat is not easy, among all cereals it is most demanding for the presence of nutrients in the soil. The whole growing season lasts 300 days and is divided into 12 stages of the organogenesis, each of which imposes its own requirements on the choice of mineral fertilizers.
For the duration of emit:
If the time of sowing is observed, there is enough moisture and all the necessary minerals in the soil, then tillering of winter wheat begins as early as 15 days after germination. Usually, tillering and going into the tube occur in the fall. In case of late sowing, lack of moisture and mineral substances, the tillering process occurs predominantly in spring.
In the fall, most of the roots are in the topsoil (15-30cm). By the beginning of winter, the primary roots reach a depth of 1 m, the secondary - 0.6 m. Usually, the formation of the root system continues until the phase of milky ripeness of the grain.
It should be noted that it is the agrarian who is interested in wheat having enough moisture and nutrients. If there is not enough moisture or minerals, then the plant will throw away one spike with the maximum number of grains possible in this situation — this is genetically programmed for reproduction. But if there is no problem with nutrition, you can expect a lot of spikelets from the plant with a large number of grains on each.
On poor soils some of the nitrogen must be introduced in the fall, necessarily with potassium and phosphorus.
If sowing is performed on the fallowed land, then vice versa - it is necessary to protect the wheat from excess nitrogen supply, for which nutrition with phosphorus and potassium must be enhanced.
Potassium increases cold resistance and increases tillering. Phosphorus - root mass growth.
The optimal ratio of phosphorus and nitrogen stimulates the growth of green mass, the development of the root system and helps the plant to accumulate a sufficient amount of sugars for winter, which increases the resistance of the plant to low temperatures.
In the case of nitrogen excess and phosphorus deficiency at the stage of germination of grains, the growth of roots is inhibited, which subsequently reduces the yield. In plants, there is an active development of loose large-cell structure of tissues with a high water content.
That is, in the autumn it is important that there is enough nitrogen, but there was no excess.
If the nutrients are not enough, winter wheat may not overwinter, seedlings have a pale green color (due to lack of chlorophyll) and tillering processes slow down, until it stops.
Generally there are two critical stages for winter wheat:
A sufficient amount of nitrogen increases the resistance of winter wheat to lodging (excess - vice versa), contributes to the good development of leaves and spikes, so it can be said with certainty that nitrogen fertilizers play the decisive role in complex measures to increase yields.
The development of the company «Comprehensive AgroService» - the self-propelled sprayer «Vodoley» is suitable for both root and foliar application of fertilizer UAN-32. Low-pressure tires «Vodoley» does not damage winter crops in the tillering stage up to 50 cm in height. High permeability – «Vodoley» is adapted for movement on the wet soil.
As experience shows, it is impossible to bring the entire dose of nitrogen that winter crops need for the entire period of development at one portion - it is necessary to divide it into several doses. The higher the estimated dose of application, the more carefully you need to consider the uniformity of its distribution over the area of the field.
It is in the spring, after the renewal of the growing season, wheat consumes up to 90% of the total nitrogen. Lack of nitrogen before the germination of a sleeping kidney leads to he cessation of the growth of this shoot. In the tillering stage, wheat prefers to give nutrients to already growing leaves and shoots, so no new ones are formed.
If a shortage of nitrogen was found during the formation of the 4th and 5th leaves on the main stem, then the plant most likely will not have time to create the first and second shoots. For a partial solution of the situation, foliar application of nitrogen should be used. If fertilizer is applied at this stage, the third and subsequent shoots will be able to grow, so the plant will consist of one main stem and two or three shoots, which will significantly reduce the yield.
In spring, during the renewal of the growing season, winter crops face a situation where the need for nutrients is higher than the capacity of the root system, for example, due to the low temperature of the soil. In this case, the exit from the situation will be foliar application of UAN-32. The active ingredient from the droplets on the leaves will very quickly be inside the plant and will provide winter wheat with nitrogen. The UAN fertilizer contains three forms of nitrogen at once, therefore it starts working immediately, plus it has a prolonged effect.
Winter wheat forms new shoots when:
With the beginning of the phase of entering the tube, new shoots cease to appear. Nitrogen reserves are directed to the growth of the main stem and new leaves on existing shoots.
What makes the introduction of nitrogen at different stages of growth:
The main amount of nitrogen will be absorbed by winter wheat in spring until the beginning of the earing growth. At the time of the start of the formation of the ear, if nitrogen is assimilated, it will be used only to improve the quality of the grains (increasing the protein content).
At the 12th stage of organogenesis (phase of wax and full ripeness of the grain), the supply of nutrients to the grain is stopped. The grains ripen, the transformation of simple organic substances into complex ones takes place - the main reserves of starch, proteins and fats are formed. Fertilizer at this stage does not make sense.
The weight of the grains depends on the size of the two upper leaves on the shoot. Foliar feeding at the beginning of the tube-out phase has a powerful effect on the growth of these leaves, so it will positively affect the overall yield. An untimely, delayed one-time foliar feeding may be ineffective if it was preceded by a long period of mineral deficiency and the plants did not have a sufficient stock of assimilants.
The protein molecule consists of several macronutrients, but separately it should be said about sulfur. This is one of the most important "partners" of nitrogen - with a lack of sulfur, the assimilation of nitrogen by plants ceases. Therefore, when introducing nitrogen, it is imperative that sulfur is also introduced in order for this nitrogen to be properly assimilated. 12 mg/kg of sulfur in soil is a disadvantage. 12 mg/kg of sulfur in soil is a disadvantage.
The recommended dose for sulfur application is either in a ratio of 14: 1 to nitrogen, or in a dose of 50-80 kg SO3/ha.
Of all nitrogen absorbed by plants, 70% will be taken off the field as a crop. For potassium, this value is 10%, but for phosphorus it is already 80%. Therefore, along with nitrogen should be monitored for the content of phosphorus in the field.
Phosphorus absorption is uneven - 30% of the entire dose will be absorbed before the tillering phase, and the remaining 70% - during the tillering phases and growing of the stem. During tillering, the bulk of the phosphorus is in the leaves, then it moves to the stem and almost all goes to the grain.
If phosphorus was not enough at the very beginning of the growing season (autumn), the underdevelopment of the root system is noted, the smaller size of the leaves, they are darker than usual, the ripening of the grains is delayed. Leaf color can change to reddish or purple.
The lack of phosphorus during the first two weeks of the growing season reduces the crop by 42% of the maximum, due to the underdevelopment of the root system and the decrease in the number of stems (Boatwrsght, Viets, 1966).
Also, the lack of phosphorus disrupts the development of grain. The total number of spikelets in a plant and the number of flowers on each of them are reduced. Phosphorus is important for the formation of ATP, a sufficient amount of which is necessary for the synthesis of carbohydrates and their delivery to grain.
This element is absorbed from the soil from the first days of growth. The maximum amount is absorbed in the phase of the output into the tube and earing. Potassium increases the cold resistance of winter crops, increases the strength of the stem, which is especially important for varieties prone to lodging and increases resistance to pathogens. Thus, potassium increases the yield of winter wheat.
With a lack of potassium in the period of intensive growth, the first thing that is found is yellow spots on the upper leaves, then, the lower leaves and the stem turn yellow. If the deficit is not eliminated at this stage, the yellowed leaves will dry out, starting from the top of the stem. The root system also suffers from a lack of potassium - the roots of the lateral shoots appear, but do not grow. Such symptoms can often be seen after the stress of a plant or during a drought.
Excess nitrogen can increase winter wheat lodging and rust damage, while potassium increases plant resistance to these points.
Soil acidity in the range of 6-7 units
Wheat is sensitive to soil pH — it’s best to have a pH of 6-7 units, so acidic soils should be alkalized.
On average, when harvesting, winter wheat takes off from the field soil: