The article presents the results of 30-year stationary experiment on the study of the effects of various types and kinds of crop rotations on the main indicators of soil fertility. The role of plants (cereals, legumes, perennial and annual grasses, row crops) in the reproduction of soil fertility is shown. The total biomass of plants entering into soil as root and aftermath residues are quantitatively reflected. The same definitions are suitable for different kinds of crop rotations: grain-grass-row, grain-grass, grain-row, and row. Balance of humus in soil in the above-mentioned crop rotations using manure and mineral fertilizing and only mineral fertilizing systems and in dependence on perennial grasses application regime and concentration is presented.

   The article analyzes the experiment results of nitrogenous fertilizers influence and methods of weed control on sweet sorghum productivity. A high reaction of the studied crop on nitrogenous fertilizer application is noticed. Application of increased nitrogen rates (N 120  и N 150 ) in two periods (at cultivation and in feeding) provides a reliable sweet sorghum increase in comparison with the total rate application. To control weeds in sweet sorghum crops it is expedient to use soil herbicides. The most effective is pre-emergent application of the preparation Primextra gold TZ at the rate of 3 l/ha.

   The results of biennial researches on the competitive assessment of productivity and chemical composition of grain and green mass of maize hybrids of "Syngenta" company are presented in the article. Their significant productive advantage over the belarusian standard is shown. It has been also established that the yield of nutrients and energy on the whole is virtually independent of quality indicators of the products grown, and therefore, it is enough to focus on dry matter yield and grain yield per unit area when assessing the productivity of silage hybrids.

   The effectiveness of green manure in fallow use improving the agrophysical soil properties, reduces unproductive evaporation from the soil surface what contributes to more complete and rational evaporation of soil moisture is shown. Seed inoculation by nodule bacteria strains under such conditions provided less seed yield increase in comparison with the average many years indicators of temperature and water regimes. Complex of factors influence on soybean productivity has revealed the compositions , allowing to accelerate growth and development of plants, decrease the disease incidence, raise efficiency and improve quality of products.

   The article presents the analysis results of morphometric germ parameters in new perspective field pea (Pisum sativum L.) varieties having different morphological types. It was shown that quantity and an average lateral root length correlated with the yield of pea seeds. Several prospective pea varieties have been selected which excelling test variety in above mentioned characteristics.

   Obtaining of proper quality regenerants is an important step in microclonal propagation of plants. In experiments with meadow clover (Trifolium pratense L.), it is established that the best spot for explant removal from a seedling is a hypocotyl section located at 0,2–1,0 mm away from the "cotyledon node". In this case, the yield of the regenerants suitable for the subsequent passage significantly grows, the regeneration time decreases. This method of the explant obtaining is applicable to other leguminous crops, however, culture media should be selected depending on plant species.

   Three years studying data (2013-2015) on vegetative and generative signs influence on selection indexes replace , range of variation by seed yield and winter rye coefficient of variation depending on the characteristics of varieties growing in soil and climatic conditions of forest-steppe of Western Ukraine are presented.

   Results of three-year researches on yield, content and removal of main nutrients with maize, barley plants and post harvest oil radish are presented in the article. Productive dominance of maize over barley and the post harvest crop is shown. 62 kg/ha or 34–36 % of nitrogen consumed by the plants, 38–41 kg/ha or 43–46% of phosphorus, and 142–149 kg/ha or 68–69 % of potassium return to soil with grain threshing during maize harvesting.

   In the article the results of many years researches on studying the dynamics of perennial weed plants growth in wild camomile and calendula crops are presented. The biological and economic efficiency of glyphosate-containing herbicides application in fields used for medicinal crops sowing is determined.

   The article presents two-year results of field experiments on the efficacy of fungicides-seed dressers of oil flax seeds. It is found that oil flax seed treatment by seed dressers Inshur рerform, SC (0,5 l/t), Lamador, SC (0,15 l / t) and Kruyzer raps (1,0 l/t) reduces seed mottling infection for 4,6–5,6 % and increases the laboratory germination of seeds for t 4,0–6,5 %. At full seedlings stage the preparation Inshur had the strongest inhibiting effect on growth of plants. Seed treatment of olive flax seeds by seed dressers didn't eliminate distribution and development of plant diseases during vegetation. The greatest productivity of seeds (17,8 kg/ha), profit and profitability are received when treating seeds by a preparation Kruyzer raps.

   The references review on biological control of greenhouse crop noxious phytophage – spider mite (two-spotted) Tetranychus urticae С. L. Koch. by using predatory mites – acariphages is presented in the article. The features of the most distributed acariphages species considering their demands to biotic and abiotic factors are shown.

   The importance of high-quality seed potato production is pointed out. The phytosanitary state of elite seeds estimation in relation to common scab (Streptomyces spp.), black scurf (Rhizoctonia solani Kühn) and silver scurf (Spondylocladium atrovirens Harz.) of potato in adjacent reproductions – super-elite  elite is given. The differences in the level of elite potato variety samples originating from different regions of the Republic infection by virus diseases are revealed. It is shown that with the use of elite seed varieties of different industrial origin and phytosanitary state a significant variation in their productivity properties is possible.

   In the article the evaluation of seed crop plantations phytosanitary condition under complicated 2015 year vegetation is presented. Based on phytosanitary monitoring results the prevalent pests and diseases and also the supposed measures on apple and pear protection in the first half of coming vegetational period are determined.

   In the article results of seed dressers Vershina, SC (tebukonazol, 30 g/l + azoksistrobin, 22 g/l) and Frasol, SC (tebukonazol, 60 g/l + triadimenol, 60 g/l) (Ltd. Frandesa) efficiency for spring grain crops protection against root rot are presented.

   The article presents the chemical composition of the false stem leek and removal of nitrogen, phosphorus and potassium main products and the balance of nutrients in the soil. Set dose of fertilizer, which provides optimal removal and the balance of nitrogen, phosphorus and potassium.

   Development of power system of water melon plants in the Republic of Belarus with low fertility potential makes it possiblet to efficiently use the combined power system. It is found that the combined power system, including the introduction of macronutrient fertilizers, micronutrient fertilizers, compost, lime materials and conducting foliar fertilizing with liquid compound fertilizer at water melon plants growth and development stages provide ia high yield with good quality products.

   In the article the results of research on the effectiveness of protective-stimulating compositions on the infection of flax seeds are presented. The positive influence of protective-stimulating compositions for seed infection of flax is determined. The high fungicidal activity of protective-stimulating compositions that contain a protectant Vitavax, Lamador, the COP, the COP Insur perfom and insectofungicide – Cruiser rape of the UK is revealed. It is shown that seeds treated by protective-stimulating compositions increase the length of the sprout on a 13–24 % in comparison with control, root length – 12.8% to 17.5%, the mass of leaves – 26.6–46.6 per cent and the mass of stems – 13–40 %.

   The article presents the results of research on the effectiveness of disinfectants and protective-stimulating compositions for processing of seeds on morphological and anatomica-ski features the stem of plants of flax. It is established that presowing treatment of flax seeds with disinfectants and protective-stimulating compositions has an influence on morphometric characteristics of the stem. The increase in thickness of the stem, depending on VA-Rianta experience ranged from 9 % to 15 %. The length of the elementary fibers increased in comparison with the control by 39 %, and the number of bed-Lesnevskih elementary fibers in a bundle ranged Valo from 30 % to 76 %.vskih elementary fibers in a bundle ranged Valo from 30 to 76 %.

   The current understanding of biological conservants used for grasses and wet grain silage making is given in the review. Components of successful vegetal raw stuff ensiling by preparations based on lactic acid bacteria depend on bacteria species, their activity, the ability to accumulate rapidly lactic acid, suppress butyric acid bacteria reproduction , enterobacteria and yeast for raising aerobic silage stability. It is actual the application of complex bioconservants based on osmotolerant lactic acid bacteria strains and various types of additives capable for promoting the fermentation process with lactic acid production.