Ways to increase the efficiency of row fertilization and humic preparations

One of the most important methods of increasing crop yields is the use of fertilizers. Of the currently available methods of application, the method of row, local application of liquid fertilizers deserves special attention, which is widely entering the practice of Ukrainian agricultural holdings.

Row application of fertilizers promotes increased plant nutrition in the very initial period of their growth and development, which leaves an imprint on all subsequent periods of plant development, largely determining their productivity. It is known what great importance leading experts in this field attached to the conditions of plant nutrition in the initial period of their development. In this regard, works on studying the composition of fertilizers applied in rows are of great practical and theoretical interest in order to maximize its effectiveness, the most complete use of the nutrients contained in it by the plant, and to ensure plant resistance to adverse external conditions.

The role of the root system and organic matter

Winter hardiness and drought resistance of plants largely depend on the development of the root system, and one of the methods that improves the development of the root system is row application of fertilizers. At the same time, the introduction of organic matter, microfertilizers and bacterial preparations into its composition seems very promising for increasing the efficiency of the fertilizer applied in the rows.

Numerous studies conducted in various soil and climatic conditions of Ukraine indicate the high efficiency of organo-mineral liquid fertilizers. The value of organo-mineral liquid fertilizers lies in the fact that when they are applied to the soil, phosphoric acid is used by the plant for a longer time and does not have a negative effect with significant drying of the soil, which is often the case in subtropical climates.

In addition, the introduction of organo-mineral substances simultaneously with seeds contributes to the rapid development of the rhizosphere microflora, which, on the one hand, mobilizes nutrients, and on the other hand, contributes to the accumulation of physiologically active substances, which, when absorbed by plants, are used by them to enhance the enzymatic apparatus.

The role of humic and fulvic acids

The organic matter of organo-mineral fertilizers can serve as a source of humic and fulvic acids, which have a positive effect on plant development and yield increase. Studies have shown that under the influence of humic and fulvic acids, which are the active substance of humic fertilizers, the synthesis of chlorophyll, reducing sugars and protein is enhanced, oxygen nutrition and the ability of plants to tolerate drought are improved. Humic and fulvic acids cause a more intense growth of the root system, which also increases the resistance of plants to adverse external conditions. In addition, humic and fulvic acids stimulate the vital activity of soil microorganisms.

Due to the fact that only soluble humic and fulvic acids have a physiologically active property, and they stimulate plant growth and development only in small doses, we set ourselves the task of studying not only the effectiveness of organo-mineral preparations in the steppe zone of Ukraine, but also to find such a ratio between the organic component and superphosphate, at which their effectiveness would be the highest.

The importance of trace elements

It was established experimentally that for the initial stage of plant development, increased nutrition with phosphorus, manganese, boron and some other elements is necessary, which has a very favorable effect on all subsequent stages of plant development and on the yield.

For the conditions of the steppe, the use of boron in row fertilization is of great interest. Boron has a positive effect on the development of the root system of plants, on the use of phosphorus and other nutrients by the plant, and also accelerates the formation of inflorescences, the development of anthers and increases the fertility of pollen, which is especially important in years with dry winds during the flowering period of plants. In addition, boron causes a more intense metabolism in the plant organism.

Manganese is of no less importance in the life of plants. Numerous studies confirm its role in physiological processes. Under the influence of manganese, the anatomical and physiological properties of the plant change, the absorption of nutrients improves. Manganese, like boron, contributes to a more economical use of nutrients by the plant to form a crop, accelerates growth and the beginning of fruiting, has a positive effect on the formation of chlorophyll, enhancing photosynthesis processes. Manganese plays a significant role as a catalyst in redox processes. In addition, it increases the number of stomata, causes thickening of cell walls and strengthening of mechanical elements of stem tissues, which can be of great importance in the fight against lodging of cereals.

The above formed the basis for studying the effectiveness of the trace elements boron and manganese in row fertilization.

The role of microorganisms and bacterial preparations

According to modern ideas, microorganisms play an extremely important role in plant nutrition. It consists not only in the transformation of organic substances into mineral (assimilable by the plant) forms, but also in the formation of specific products — vitamins and growth stimulants, which play a huge role in the biochemistry of plants and their nutrition. The leading factor of soil fertility is its biological activity.

Given these ideas about the microflora of plants, it seemed appropriate to us to conduct studies in which the effectiveness of organo-mineral fertilizers, which would include a bacterial preparation, would be studied. For this purpose, in the conditions of the chernozem zone of Ukraine, the introduction of phosphorobacterin into the composition of organo-mineral granules seems most rational.

Description of studies

Based on all these provisions, we conducted special studies over a number of years. The experiments were carried out in the Chernihiv region. The experiments were laid on ordinary low-humus chernozem. Vegetation experiments were carried out in soil and sand cultures. Experiments with winter wheat were laid according to three predecessors: fallow, second winter crop after fallow and layer rotation, and with spring wheat — according to the layer of perennial grasses.

The size of the plots in field experiments was 200 m² with 4-fold repetition, in production experiments — from 1 to 5 hectares of one repetition, in laboratory field experiments — 2.5–10 m² with 6–8-fold repetition.

Trace elements

To study the effect of trace elements on increasing the efficiency of row fertilization, enrichment of liquid organo-mineral fertilizers with trace elements was carried out:

• Boron: 1, 2.5, 5, 10 and 15% borax by weight of superphosphate.
• Manganese: 1, 2, 4, 5, 8, 16% manganese sulfate.

Bacterial preparations

To study the effect of bacterial fertilizers on increasing the efficiency of row fertilization, phosphorobacterin was tested both by seed inoculation with simultaneous sowing with fertilizers, and by introducing it into the fertilizer composition.

Cuttings and seedlings were treated with liquid fertilizers during sowing. Experiments were established with winter and spring wheat.

Observations and accounting

During the growing season, in addition to phenological observations of the development phases, the following were carried out:

• Measurement of plant height and counting the number of leaves on the main stem.
• Determination of tillering and yield structure.
• Observations of the formation of primary and secondary roots and their distribution in the soil (lysimetric experiments).
• Observations of the development of the rudimentary ear. Its size was measured under a microscope, and the drawing was made using a drawing apparatus.

The yield was recorded by the method of continuous threshing. Yield data were processed mathematically.