The article presents the characteristics of the soil-cultivating multifunctional APM-6A aggregate and the direct seeding machine SPP-9, created in Belarus, their use in the combined tillage of sod-podzolic sandy loamy and sandy soils subject to wind erosion is justified.

   The article presents the results of competitive testing of varieties of red clover of different types of ripeness. As a result of a comprehensive evaluation, the best varieties of meadow clover of different types of ripeness are distinguished in competitive variety testing, capable of forming a stable yield of green mass and seeds in sharply different weather conditions and characterized by high feed nutrition.

   In the article the analysis of the 57 collection samples of flax under some agronomic characteristics of productivity and fiber
quality, depending on ecological and geographical origin are shown and their comparative evaluation, the feasibility of using in the selection process.

   It is established that on the peat-mineral soil the minimum accumulation of ¹³⁷Cs with perennial leguminous grasses is noted at a nitrogen-potassium ratio of 1 : 0.4–0.6. At a ratio of 1 : 0.2–0.3, nitrogen deficiency and an increase in radionuclide concentration in hay are observed due to a decrease in yield. The introduction of high rates of nitrogen fertilizers on a low background of potassium nutrition broadens the N : K ratio, which is accompanied by the formation of a potassium deficiency and a decrease in the discrimination of ¹³⁷Cs with respect to potassium when entering plants. An increase in the accumulation of a radionuclide in the hay is observed at a ratio above 1 : 0.8.

   The results of investigations on the effectiveness of mineral fertilizers application at winter wheat growing after different
predecessors in a Steppe of Ukraine are presented in the article. It was found that after a couple of black, peas and sunflowers on backgrounds of recommended food most significant increase winter wheat yield compared to the control provided nitrogen fertilization in different phases of plant development.

   In the article the results of itinerary inspection (2011–2016) of main grain crops for perennial weed plants infestation before yield harvest of main winter and spring grain crops in Belarus are presented.

   Western floral thrips (Frankliniella occidentalis Perg.) Has the status of a quarantine pest in Ukraine and is potentially dangerous for vegetable and ornamental crops in greenhouses in Ukraine. The total area under quarantine for today is 12,62 hectares, thrips is distributed in greenhouses of 6 regions. As a result of the phytosanitary examination, it was established that western floral thrips falls into Ukraine in samples taken from imported potted plants, cut flowers, greens, lettuce and tomatoes. High efficiency against imago and larvae of the western flower thrips is provided by the Spintor 240 sc, ks (spinosad, 240 g / l) with a rate of flow of 0.03–0.05 l / 100 l of water with two sprayings during the growing season in vegetable crops 83,5–88,7 %, flower – 94,5-97,7 %.

   The article presents the results of application of the PCR method for the diagnosis of Belarusian Apple mosaic virus isolates (ApMV) in hop. It was established that the PCR method with the use of a pair of primers to the gene of viral coat protein (PAPMCP-5/PAPMCP-3) can successfully be used to detect ApMV in hop in Belarus. As a result of the molecular genetic analysis, sections of genomes of three Belarusian ApMV isolates in hop were sequenced for the first time, the nucleotide sequence of which was placed in the international database (EMBL/GenBank) with identification numbers: LT546544, LT546545 and LT546546. Phylogenetic analysis of nucleotide sequences of isolates of ApMV in hop showed that the grouping of the isolates did not depend on their geographical origin. The analyzed virus isolates formed three subgroups, and the Belarusian isolates were in two of them.

   On the basis of tests carried out in 2014–2016 the positive impact of a growth stimulant and micronutrient fertilizers on the
accumulation of sugars in root of the neck, which ensured a high percentage of overwintering plants of winter rape.

   Data on taxonomic spider structure on the fields of winter rape are listed. We estimated the species composition, abundance and meeting of spiders on the winter rape fields. Our data on the structure of species composition allow to optimize the use of protect means on the winter rape fields.

   The article presents the results of many years of research on the number of interspecific populations of grasshoppers in the field on winter wheat crops, taking into account the vegetative period of the crop: autumn and spring-summer.

   Fungi Alternaria alternata, Alternaria tenuissima, Alternaria infectoria, Sclerotinia sclerotiorum, Botrytis cinerea growth and development features in laboratory and field conditions were determined. Their pathogenic properties and influence on crop during the growing season were established. Thermal factors effects on the sclerotia fungi formation in S. sclerotiorum and B. cinerea were shown. Sunflower seeds’ overall contamination dependence on the average daily temperature and precipitation during the budding-flowering period was revealed (r = 0.98).

   The article analyses the condition of planting material production of fruit crops in the Republic of Belarus. The results of studies on nursery growing are generalized. The main directions of further nursery development and its scientific supply are determined.

   The article presents the results of studies on the effectiveness of pre-harvest treatment application of chemical and biological agents on the susceptibility of apple fruit diseases during vegetation and storage. Determined that use of chemical and biological agents affects the reduction of fruit losses from infectious diseases during the growing season and during prolonged storage. The most effective among tested preparations was chemicals agents: Bellis, Luna tranquility and biologicals agents Ekosad and Alirin B at three time application.

   Recently, strawberries and raspberries are becoming intensive type crops, as the main emphasis is put on obtaining high and stable yields due to the use of modern complex water-soluble fertilizers. A study of the components of productivity and yield was carried out on zoned strawberry variety 'Kimberly' and raspberry variety 'Babie leto'. As a result of the conducted studies it was found that the use of the preparation Volat-24 promoted an increase in the number of both flower stalks and the number of berries in strawberry experimental plantations compared to the control (75 % and 65,4 %, respectively). When using Volat-24, the yield of strawberry was experimental plantations 13,7 t/ha, which exceeded the control by 60 %; raspberry in the repair – 13,3 t/ha or 17,8 % higher in comparison with the control variant.

   The article describes the results of researches on studying of influence of agrotechnical methods on productivity, chemical structure of plants and quality of production of broccoli cabbage.

   It is established that when a watermelon is cultivated with the help of seeds, the root system is formed at the depth of 4,1–28,9 cm from the soil surface in the early tierum variety, at the depth of 4,2–49,2 cm from the soil surface in the mid-late Icarus variety. Watermelon root system during the cultivation with the help of cassette seedlings develops at 4,0–8,5 cm soil layer, with the help of the potted plant – at 4,1–12,5 cm soil layer regardless of the variety. When sowing seeds with a shift from the seeding capacity center, a single-sided root system development takes place, which makes it difficult for mechanically plant and reduces the yield by 28,2–29,2 further. As the watermelon grows and develops, the osmotic pressure of the root increases from 2,25 to 5,2 atm, which reflects the watermelon drought resistance increase in ontogeny.

   On November 16, 2017, the session of the General Meeting of the NAS of Belarus and the election of full members (academicians), corresponding members of the NAS of Belarus took place. In the Department of Agrarian Sciences, Ivan Ivanovich Golub, Director of RUE "Flax Institute" of the National Academy of Sciences of Belarus, was elected a full member (academician) in the specialty "Agro-industrial Technologies", a corresponding member in the specialty "Breeding and seed
production of agricultural plants" was elected Deputy Director General for scientific work of RUE "Scientific and Practical Center NAS of Belarus on Agriculture" Eroma Petrovich Urban.