On the basis of experimental data, the article evaluates the productivity of agrophytocenoses with various types of perennial forage crops. It was found that the inclusion of forage crops in the composition of grass mixtures, which have a high rate of growth of aboveground mass and productive longevity, contributes to an increase in the yield of green mass during the four-year use of these crops. The most productive longevity among the studied variants was characterized by multicomponent grass mixtures, which, on average, over four years of use, formed a yield of green mass at the level of 477,2–480,0 c/ha. The collection of raw protein in them was 11,42–12,05 c/ha, the yield of exchange energy was 9,87–10,82 GJ/ha.

The article presents the results of studies to study the dependence of the yield of green mass of the Sudanese grass on the fractionation of seeds using an aerodynamic separator. Pre-sowing fractionation of seeds makes it possible to form batches of seed material, the seeds of which are distinguished by evenness and uniformity in the weight of 1000 seeds and sowing qualities.

The results of studies on assessing the effectiveness of fertilization systems for spring rape, depending on weather conditions the presents in article. The optimal system for fertilizing crops on sod-podzolic loamy soil with a high content of phosphates and potassium is the complex application of N₉₀₊₃₀P₄₀K₆₀ in combination with boron fertilization against the background of the aftereffect of 60 t/ha of straw manure. As a result 12,9 c/ha of edible oilseeds food purposeare formed, or 50 % to the option without fertilizers. The share of mineral fertilizers in the formation of the yield of spring rapeseed under unfavorable weather conditions is increases more than 2 times (up to 58 %, including nitrogen fertilizers – up to 47 %).

The article presents the effect of fertilizer systems on the yield and Transfer factor (TF) of ⁹⁰Sr into the green mass of sugar sorghum cultivated on sod-podzolic sandy loam soil. A decrease in TF of ⁹⁰Sr in the green mass of sugar sorghum was noted with an increase in the dose of phosphorus fertilizers up to 10 %. With the applying of NPK in the crops of sugar sorghum, the lowest TF of ⁹⁰Sr in the green mass was observed with the fertilizer system like N₇₀P₆₀K₈₀ and N₇₀P₆₀K₁₀₀. A strong inverse correlation was established bet ween the hydrothermal coefficient and TF of ⁹⁰Sr in the green mass of sugar sorghum. It is shown that the maximum yield of sorghum is provided by the fertilizer system N₉₀P₆₀K₁₀₀ and the yield of sorghum depends on the degree of moisture in the growing season.

The article analyzes the economic efficiency of the use of organic, macro-, micronutrient fertilizers and growth regulator in the cultivation of corn for grain and green mass.
It has been established that in the conditions of sod-podzolic light loamy soils in the north-east of Belarus, the most optimal agroeconomic indicators of the Ladoga hybrid corn are possible with the use of complex fertilizer Kristalon against the background of mineral fertilizers at a dose of N₉₀₊₃₀P₇₀K₁₂₀.

Depending on the treatment of seeds of winter wheat varieties with micronutrient fertilizer granular «5 element», the sowing quality increased. Namely, pecking activity by 6–8 %, germination energy – by 3–4 %, laboratory germination – by 2–3 % and field germination – by 5,4–7,1 %. On variants with the use of microfertilizers, the number of productive stems increased by 13–42 pcs/m², the number of grains per ear – by 2–6 pcs. and the weight of grain per ear – by 0,1– 0,4 g. The use of micronutrient fertilizers for seed dressing and on sowing winter wheat in the spring-summer growing season increased the yield of varieties by 0,33–0,65 t/ha and the yield of conditioned seeds by 4,1–7,0 %. The maximum yield (5,39–6,11 t/ha) and the yield of conditioned seeds (77,6–81,1 %), depending on the variety, were obtained in variants with treatment with a dressing agent together with micronutrient fertilization and its introduction at IV and VIII stages of organogenesis.

The article presents the results of research on the effectiveness of the use of herbicides in the cultivation of corn. It was found that in the weather conditions prevailing during the research period, the greatest effect in protecting corn crops from weeds was obtained when using the herbicide MeisTer Power, MD (1,3 l/ha) in phase 3 of the crop. The average loss of weeds was 94,1 %, the decrease in their raw weight was 98,3 %, the increase in the yield of green mass was 400,4 c/ha (165,4 %), and grain – 65,7 c/ha (227,3 %).

It is shown the results of biological and economical efficacy investigation of 12 seed dressers for spring barley protection against diseases in 2015–2020. Investigations were done on the high level of seed contamination with Fusarium spp. (up to 36,0 %) and Alternaria spp. (up to 94,0 %), and biological efficacy of seed dressers was 87,5– 100 and 45,7–93,1 %, respectively. Biological efficacy It is shown the results of biological and economical efficacy investigation of 12 seed dressers for spring barley protection against diseases in 2015–2020. Investigations were done on the high level of seed contamination with Fusarium spp. (up to 36,0 %) and Alternaria spp. (up to 94,0 %), and biological efficacy of seed dressers was 87,5– 100 and 45,7–93,1 %, respectively. Biological efficacy

The article presents three-year studies data on the effectiveness of seed dressing agents Scarlet, ME (0,4 l/t), Kinto plus, SC (1,0 l/t) and Inshur perform, SC (0,5 l/t) for fodder beans protection against the diseases. The studied preparations have ensured grain infection decrease by fungi of the genus Alternaria, Fusarium and Botrytis fabae up to 10,0–14,5 %, have contributed to the preservation of 4,0– 5,0 cwt/ ha of grain and obtaining a conditional net income 118,5–134,0 rbl./ ha.

The results of studies on the biological and economic effectiveness of the fungicide Сuproxat, SC for the protection of nightshade crops against late blight and alternaria blight are presented. It is determined that three times preparation application inhibits the development of late blight and alternaria blight in tomato plantings in greenhouses up to 60,5 and 64,3 %, open ground tomato – to 60,9 and potatoes – to 50,2 and 77,2 %, respectively. The harmful diseases development reduction contributes up to 18,0 to 28,7 % of nightshade crops yield preservation.

The paper presents the results of studies on the effect of herbicides on the suppression of weeds during the preparation of flax trusts by the dew lobe method. For the destruction of weeds in the spread ribbons of fiber flax, it is advisable to use the herbicide Tornado 500 with a consumption rate of 1–2 l/ha, depending on the phase of development of weeds at the time of processing and weather factors, providing trusts with a standard weediness of up to 5 % without reducing its number and fiber content, as well as without increasing the amount of glyphosate in the trust.

The article presents the results of research on the yield and biochemical composition of the production of white cabbage and beetroot in the conditions of the Republic of Belarus for the period 2011–2012. The optimal doses of mineral fertilizers and vermicompost were revealed when growing vegetables on sod-podzolic light loamy soil.