The goal of the research was to determine the nitrogen-fixing ability of perennial leguminous grasses and their use of biological nitrogen to form the crop of fodder in different environmental conditions of Western Siberia. The nitrogen-fixation coefficient (Cf) was determined by the method of comparison with a non-leguminous plant. It has been established that in the southern forest-steppe on meadow-chernozem soil biological nitrogen is used more efficiently using Medicago varia, Galega orientalis, Onobrychis arenaria и Astragalus galegiformis. Plants of these species fix up to 233–379 kg/ha of air nitrogen during the growing season, Cf is equal to 0.56–0.78. The accumulation of symbiotic nitrogen by leguminous grasses is 1.1–4.6 times less in the northern forest-steppe in solonetz fine than in meadow-chernozem soil. Medicago varia at solonetz forms due to biological nitrogen to 58% of yield and Astragalus galegiformis only 10-22%.

The article presents the five-year results of the studying the adaptation of varieties, and hybrids of Jerusalem artichoke in the forest-steppe of the Omsk region. The analysis of biometric indicators and crop yield structure is presented. The dynamics of the accumulation of herbage, as well as the periods of the passage of phenological phases are shown. The chemical composition of plants is determined. The studies show that many hybrids and varieties in Western Siberia do not go through the flowering phase, but at the same time form a full-fledged tuber crop. At the same time, the high yield of the aerial mass of Jerusalem artichoke does not always ensure a high yield of tubers. On average, for five years of research, the French D-5 hybrid, Canadian sample and variety samples’ No. 1 and No. 9 we distinguished in terms of herbage productivity. This indicator was 49.4-58.9 t / ha. In terms of tuber productivity, the best varieties were No. 9 and No. 12, as well as the Sireniki-1 variety (29.1-30.2 t / ha). The distinguished varieties and hybrids of Jerusalem artichoke are recommended for the introduction into production in order to improve the forage base of agricultural enterprises. The research on the selection of varieties and hybrids in order to obtain high-tech tubers (large and aligned) for processing in the food industry will be continued.

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The method of holographic interferometry is finding ever wider use when studying the deformation properties of cement and concrete for detecting cracks under mechanical loads [I]. With the use of the possibilities of holography [2], in the present work displacements during plastic deformation and the effect of temperature on nonioaded specimens were analyzed.We investigated compressive strain of concretes (grade 300) (with granite aggregate) and cement (grade 500). The concrete specimens (20 x 30 x 80 nun) with a 56% volume content of granite aggregate (particle size from 2 to 20 mm) were tested under longitudinal loading, and the cement specimens (4 x 40 • 80 mm) under transverse loading at the center with respect to a 50-mm generatrix. Deformation of concrete specimens with granite and haydite aggregates at temperatures from 20 to 60~ was also determined.