An analysis of the results of experimental data on assessing grain yield and collecting raw protein during the cultivation of leguminous crops in the northern part of the Republic of Belarus showed that the collection of seeds at the level of 40 с/ha was formed by the pea varieties Fatset and Phaeton and the variety of fodder beans Bobos. The narrow-leaved lupine variety Zhodinsky provided a seed yield of 37,6 c/ha. The protein collection from the Zhodinsky variety was 13,05 c/ha, from the Bobos forage bean variety – 12,56 c/ha, and the Phaeton pea variety – 10,59 c/ha.

The article presents the results of research on the influence of regular dose loads of liquid cattle manure, pig manure effluents and poultry manure on the enzymatic activity of sodpodzolic soils; an assessment of the activity of mineralization processes in cycles C and N and humification in cycle C; the analysis of data on the direction of transformation of organic matter in soils based on the use of a biochemical coefficient is carried out.

The article presents the results of fungicides effectiveness study in sugar beet crops depending on the harvest time. As a result researches, it is found that for epiphytotic Cerсospora beticola Sacc. and early harvesting of sugar beet, fungicidal treatments of hybrids with medium and high sensitivity to Cerсospora beticola Sacc. should be carried out no later than August 10–15, and for medium and late harvesting until August 20. Treatment with fungicides at the depressive disease development for middle and late harvesting periods is inappropriate. For hybrids sensitive to Cerсospora beticola Sacc., double application of fungicides is expedient for all harvesting periods, for resistant hybrids, two treatments are optimal only if they are harvested after October 6.

Winter wheat protection system, including seed treatment with the seed dresser Orius Universal (2,0 l/t), weed control at 2–3 leaves of the crop stage with the herbicide Trinity (2,5 l/ha), the growth regulator Calma application (0,5 l/ha) and the use of fungicides Custodia (1,0 l/ha; BBCH 34–37) and Zamir (1,2 l/ha; BBCH 61), has provided with 86,1 cwt/ha grain yield. For this, the biological effectiveness of Trinity (2,5 l/ha) has made 95,4–98,6 %, Oriius universal – 57,6 % against snow mold and 70,0–81,3 % against root rots, fungicidal protection against septoria leaf spot – 59,9–75,5 %, septoria ear spot – 77,3 % and 62,2 % – fusarium head blight.

In the article the data on protective measures influence on economic parameters of winter rye grain production are stated. The method of the crop protection optimization at different levels of planned yield is proposed.

The work presents the results of three years of research on the cultivation of intermediate crop crops (buckwheat, oilseed radish, white mustard, spring rape) for green manure during compaction of the crop rotation link in the north-eastern part of Belarus on sod-podzolic medium loamy soil. Under satisfactory conditions of planting and plant development, the formation and plowing of 11–22 t/ha of green mass containing 0,8–1,2 % nitrogen, 1,1–1,6 % phosphorus, 1,2– 2,2 % potassium, increases the respiration rate of the soil by 14–36 % and its biological activity according to the degree of decomposition of linen linen by 6–9 %; reduces the density of the soil in the root-forming layer by 3–10 %.

This article presents the results of studies on the effect of foliar application of the complex fertilizer KompleMet-Сa on the quality of the fruit and the preservation of the apple crop of the late ripening variety Nadzeyny. It was established that when foliar application of KompleMet-Сa fertilizer in the Nadzeyny variety was found, there were significantly more dry matter, soluble solids, titratable acids, and the amount of sugars. The introduction of complex fertilizer helped to reduce the natural decrease in fruit mass during storage by an average of 2,5 % (more than 2 times), as well as their better preservation – with the release of healthy fruits 92,1 %.

The article presents experimental data on the change in morphometric indicators of cabbage seedlings and the effect on the yield and marketability of products in the future, depending on the doses of complex granular organic fertilizers of prolonged action.

The inclusion in the 2-component crops of spring triticale and oats with spring vetch of a new component – oil radish with partial (50 % of the seeding rate) and complete (100 % of the seeding rate) replacement of the bean component in the mixture provided an increased the total content of leaves in the yield from 7,79–9,69 to 8,33–10,71 t/ha. At the same time, the content of high-protein components in green fodder also increased: in a mixture with spring triticale – to 53,7–54,5 %, and with oats – to 49,7–52,4 %.

The introduction of oil radish into the triticale-vetch mixture provided an increase on average over three years of green mass productivity by 1,49–1,98 t/ha, and collection of absolutely dry matter – by 0,08–0,10 t/ha. When using cruciferous component in joint agrophytocenoses with the participation of oats, the yield of green mass increased by 1,77–2,98 t/ha and the collection of absolutely dry matter – by 0,06–0,14 t/ha, and the feed quality indicators improved.

Pre-sowing seed treatment with insecticides reduced leaf affection at seedlings stage (2–3 leaves) by cereal flea flea beetles from 47,9 % (the insecticidal-fungicidal preparation Yunta Quadro) to 56,2 % (the insecticidal disinfectant Tabu), as well as shoots damage by intra stem pests, namely, Frit flies larvae at 40,2 % (Tabu preparation). The combined effect of organo-mineral fertilizers and pre-sowing seed treatment with the systemic products contributed to 2-fold grain yield increase compared to control.

The article deals with the actual problem of studying the system of chemical control of level of weediness of oilseed radish agrophytocenosis. It is at the level of 81,6–85,4 % with the maximum value of the variants of combined use of herbicides according to the scheme of Halera 334 SL (0,3 l/ha) + Selekt (0,7 l/ha). It allows to provide a seed yield level of 1,69 t/ha, it is by 0,86 t/ha higher than on the control, that is, ensures that the crop retains a double index to control.