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The results of studies on the assessment of the influence of the elements of the narrow- leaved lupine cultivation technology on its productivity are presented. It has been established that when it is placed in a crop rotation after unfavorable predecessors, this indicator decreases by 38– 69 %, and with permanent sowing – by 83,3 %. The use of herbicides increases the grain yield of narrow- leaved lupine by 15,9–41,2 %, insecticides – by 6,9–11,3 %, fungicides – by 8,1–10,0 %, microelements – by 13,4–29,0 %, semi-fallow tillage and pre-emergence harrowing of crops – by 19,2 %. When effective herbicides are used, moldboard plowing, nonmoldboard, shallow tillage, direct sowing into uncultivated soil do not differ significantly in their effect on the grain yield of this crop.

The effect of epibrassinolide in combination with salicylic acid and methyl jasmonate on the number and weight of potato mini-tubers, its content of dry matter, starch and ascorbic acid was studied. A synergistic interaction was revealed under optimal growing conditions for mixtures of epibrassinolide with salicylic acid and methyl jasmonate in relation to a viral infection, which consists in increasing the productivity and quality of the obtained mini-tubers. Under the combined action of water deficit and biotic stress, treatment with epibrassinolide reduced the degree of potato vurus Y infection while maintaining productivity at the level of infected plants and improved product quality. At the same time, treatment with a three- component mixture provides the largest mass and number of mini-tubers obtained, however, a protective effect against viral infection was not manifested in this variant of the experiment.

The effect of basic and fractional application of carbamide on corn yield depending on weather conditions was studied in four-year experiments on the connected sandy soil of the Scientific and Practical Center of the National Academy of Sciences of Belarus for Agriculture. It is shown that the introduction of carbamide at a dose of 90–120 kg/ha of nitrogen against a background of 50 t/ha of manure provides a significant increase in yield relative to the control variant without nitrogen (15,6–22,8 % for dry matter and 17,2–25,9 % for grain), but has insignificant differences within the specified application rate. Fractional application of carbamide (N30 in pre-sowing cultivation + N60–90 scattered in 7–8 leaves) contributes to the formation of a higher harvest of dry matter by 2,7–5,1 %, grain by 4,8– 6,9 % compared with a single introduction of the entire dose in pre-sowing cultivation.

The article presents data on the effect of seeding rates and the dose of mineral nitrogen on the productivity of pea crops for grain fodder purposes. In the soil and climatic conditions of the northern region of Belarus, against the background of the application of N 65 kg/ha a. i. and a seeding rate of 1,9 million germinating seeds per hectare, the maximum indicators for the yield of pea seeds and the collection of crude protein were obtained, which amounted to 47,5 centners per hectare and 8,9 centners per hectare, respectively. Treatment of pea seeds before sowing with Rizoverm contributed to an increase in sowing productivity at a seeding rate of 1,9 million/ha of germinating seeds by 5 c/ha, and at a seeding rate of 2,2 million/ha – by 6,7 c/ha.

The results of phytosanitary monitoring of winter cereals fields show an abundance of bent grass and young dicotyledonous weeds. This explains the rational tactics of using intensive broad- spectrum post-emergence herbicides in winter cereals. In light of this, one of the important issues is the study and comparative analysis of the efficiency of modern preparations in this segment. In two-year field experiments the effect of herbicides Complete Forte, SC; Alister Grande, OD; Marathon Plus, SC; Trinity, SC; Fixit, SC on weed infestation and yield of winter wheat was studied. It was established that Alister Grande, OD used at a dose rate of 0,8 l/ha had the maximum biological and economic efficiency, ensuring 99,6 and 99,7 % of weeds death over the years and the level of safeguarded yield of 35,25–38,05 dt/ha.

The article presents the results of studying the effectiveness of the use of DR GREEN fertilizers on winter wheat. It has been established that foliar fertilizing of winter wheat with DR GREEN fertilizers improves the quality and increases the yield of winter wheat grain, as well as provides additional income of about 100 rubles/ha.

In the article data on the biological and economic efficiency of herbicides and their tank mixtures in winter wheat crops are presented. The results of the research showed that with a mixed type of contamination, the biological effectiveness of the tank mixture of herbicides Lastik Extra, CE + Ballerina Super, SE averaged 86,7 % in number and 98,2 % by weight of weeds, tank mixture Lastik Extra, CE + Ksior, CE – 79,7 and 95,9 %, respectively, over the years of research. Reducing the contamination of crops contributed to an increase in crop yield – in the variant with the use of a tank mixture of herbicides Lastik Extra, CE + Ballerina Super, SE, the stored yield compared to the control variant was 10,5–11,8 cwt/ha, tank mixture Lastik Extra, CE + Ksior, CE – 7,7–9,4 cwt/h

The article presents the data on the phytopathological state of carrot  tubers stored for 6 months in vegetable storehouses in Belarus. It was established that the dominant disease of tubers was white rot, the maximum prevalence of which reached 44,8 %. The maximum incidence of gray rot and black rot was 11,3 % and 9,7 % respectively. The occurrence of new diseases was noted: fusarium, violet and pocket rot. After 6 months of storage, a complex of diseases was most often present on the studied varieties and hybrids of carrots, of which white-black (47,1 %) and white-graypocket (29,4 %) rot dominated.

The article presents the results of studying the effectiveness of pre-sowing treatment of fiber flax seeds with protective- stimulating compositions (ZSS) based on the biopreparation Biolinum, Zh (2,0 l/t), the disinfectant Vitaros, VSK (1,5 l/t) and microfertilizer Ecogum of various grades (0,5 l/t). The maximum increase in the field germination of seeds in relation to the control on average for 2018–2020 was 2,3 % under the influence of the composition Biolinum + Ecogum zinc, copper, boron- complex, and plant storability – 1,9 % when using ZSS Biolinum + Ecogum Bio and Biolinum + Ecogum Bio + Vitaros. The use of ZSS contributed to the reduction of seminal infection by 17,3 %. The maximum reduction in the total infection of seeds with diseases with a biological efficiency of 62,0 % was achieved under the influence of ZSS Biolinum + Ecogum zinc complex + Vitaros, Biolinum + Ecogum Bio + Vitaros and Biolinum + Ecogum zinc, copper, boron complex + Vitaros. These ZSSs provide the maximum effect in reducing the development of diseases in fiber flax crops at the stage of early yellow ripeness: biological effectiveness against anthracnose was 63,0–66,7 %, fusarium – 70,0– 93,3 %, sallow – 79,3–80,3 %.

The article shows the effectiveness of the action of the microbial preparation Polybact, G which affects the field germination, survival and photosynthetic activity of flax plants. An increase in the field germination of flax seeds was found with the introduction of the microbial preparation Polybact, G, which, depending on the year of research, varied within 81,8–85,0 %. The survival rate in the variant using Polybact, G was in the range from 74,5 % to 82,7 %. The introduction of Polybact, G (3,0 l/ha) into the soil for winter plowing increases field germination by 1,7 %, survival by 0,8 % compared to the control. The maximum number of leaves was noted during the flowering phase in all variants of the experiment and varied between 50,3–52,7 pieces. The area of leaves per hectare of sowing in the "herringbone" phase on average for 2018– 2020 when using the drug Polybact, G was at the level of 15,5 thousand m²/ha. The maximum values of this indicator were noted in the flowering phase when using the drug Polybact, G. The excess over the control variant was 13,0 %.