Vol 43, No 1 (2017)

The analysis of the effect of deficiency of mineral elements on a number of traits characterizing morphotypes and productivity of rice varieties of Russian, Italian, and Chinese selection was performed in the study. Russian varieties exceeded all studied foreign variety by the weight of the root system, but they exceeded only Italian varieties by the length of root system. The results of the study demonstrated that the deep root system provides significantly higher productivity of the main panicle of plants under stress (phosphorus deficiency). Phosphorus deficiency increased the length of the root system in both groups with shallow and deep root systems, but the increase was more significant in the group with shallow root system.

To assess the potential use of pea defensin gene for protection from phytopathogens, some independent transgenic lines Medicago lupulina L. cv. Mir were obtained by agrobacterial transformation. Regenerants and their seed progeny were analyzed by PCR. To evaluate the potential resistance of the seed progeny selected by field experience (T1, which confirmed the presence of the target transgene by PCR), the mixture of cultural filtrate of highly virulent isolates of Fusarium (F. culmorum, F. sambucinum, F. oxysporum, F. avenaceum, F. gibbosum) was used. An increase in resistance of the studied transgenic lines was demonstrated to the toxic effects of Fusarium damage.

In the present study, 39 endophytic bacteria were isolated from different crops with main focus on maize roots and seeds. Endophytes were screened for drought stress tolerance, plant growth promoting (PGP) traits and antifungal activity. Out of 39 isolates, 32 could show drought tolerance up to–1.02 matric potential (MPa) and exhibited most of the plant growth promoting traits. But, only five isolates could show antagonistic activity against plant fungal pathogens. Based on the results, 10 promising isolates namely FTR, NFTR, FMZR9, FMZR2, MZ30V92, MRC12, MRC31, MRC33, MRC41 and MRR2 were selected and identified using biochemical and 16S rDNA gene sequencing as Pseudomonas aeruginosa (strains FTR and NFTR), Pseudomonas monteilii (strain FMZR2), Pseudomonas putida (strain FMZR9), Acitenobacter brumalii (strain MZ30V92), Enterobacter asburiae (strain MRC12), Sinorhizobium meliloti (strain MRC31), Pseudomonas thivervalensis (strain MRC33), Pseudomonas fulva (strain MRC41), and Pseudomonas lini (strain MRR2). Further, at–1.02 MPa all the 10 isolates showed PGP traits, and 3 isolates (FTR, NFTR and MRC12) showed antifungal activity. Thus, indicating that drought tolerant plant growth promoting antagonistic endophytic bacteria (PGPAE) helps in plant growth and disease management under drought stress.

It has been indicated that the use of continuous fallow and monoculture farming systems tend to decline the soil humus content, transform the soil-absorbing complex, decrease rapidly the cellulose decomposition rate and the Fenzyme (oxidoreductase and hydrolase) activities, and sharply increase the phytotoxicity. The annual applications of fertilizers at the medium doses to corn in the crop rotation have favorable effects on the leached black soil fertility. However, their long-term applications in both the corn monoculture and the crop rotation can contribute to the insignificant increase in the soil actual and hydrolytic acidity.

It is shown that the optimal value of the photosynthetic potential determining the level of productivity of agricultural crops is achieved mainly by selecting varieties and hybrids that are adapted for every growing area and taking into account the time of their physiological activity and the high intensity of photosynthesis. A model of photosynthetic potential in irrigated light-brown soils in the system of forest belts is given. The regularity of the functioning of agroforestry systems in the form of exponential dependence has been revealed for forecasting maize bioproductivity.

The aim of this paper is to study effects of GH and DGAT1 gene polymorphisms on feeding qualities of Hereford and Limousin bull calves bred in conditions of the Cis-Ural steppe zone. SNPs of genes GH and DGAT1 are investigated by polymerase chain reaction (PCR) and DNA restriction fragment length polymorphism (RFLP). The studied population of animals was assessed by defining the allele frequency and animal genotype occurrence for the studied gene SNPs, indicators of the actual and expected heterozygosity, and Pearson’s test. A study of polymorphism C214G of gene GH revealed that genotype LL prevails in Hereford and Limousin animals, 47.37 and 57.7%, respectively, while frequency of allele L is higher in Limousin bull calves (0.731). A study of polymorphism K232A of gene DGAT1 gene in both the populations showed absence of genotypes AA, which can be related to the low number of the studied animals. Expected heterozygosity indicators of gene GH are higher than the observed ones, and the observed heterozygosity is higher for DGAT1. The number of efficient alleles for the studied genes is higher for Hereford bull calves. In general, according to Pearson’s test, both the studied populations are in equilibrium. There is a significant effect of GH gene polymorphism on live weight gain rates at the end of sagination and total and average daily weight gains during animal raising.

The objective of this paper was to study in vitro the complexing ability of anionic polyelectrolyte in relation to model protein to develop a new type of polymeric feed additive for agricultural animals. It has been established that the investigated polymer with a molecular weight of 1 × 10⁶ forms interpolymer complexes with model protein, namely, bovine serum albumin (BSA). The degree of the formation of these complexes significantly depends on the acidity of the medium and the ratio of components. It has been established that these complexes are formed in a wide interval of the ratio of components, i.e., both in the excess of protein in relation to polymer and in the excess of polymer in relation to protein. It has been revealed that 2.0–2.5% of BSA is complexed under conditions that are similar to the conditions of ruminant forestomachs at reaction medium pH 5.0–6.5 and a polymer-to-protein weight ratio of approximately 0.3 × 10^–3.

In the model system mice–A. tetraptera, cancelation of the nematode activity of Nilverm, in case of combined application with Imunofan, was detected. It was ascertained that Imunofan in a dose of 0.025 mg/kg, in case of double introduction, does not possess protective and selective effect on immune reactions. Joint effect of the drugs is determined by the primary stimulation of humoral immune response, which is dependent on T-helpers.

This article considers the conditions for creating the soil-cutting blade wear model proceeding from abrasive wear mechanics. The basic determiners of the nature and rate of blade wear are identified. The influence of external factors is considered that are related to power consumption for overcoming the soil resistance to destruction. The soil resistance forces include the ones that deform the soil at compaction, and the inertia forces that originate at the uplift and displacement of the soil layer. The necessary and sufficient conditions for creating a model similar to natural in the domain of desired properties are considered. The similarity criteria of the model-nature system are determined that characterize the processes observed during the blade wear in actual soil conditions. The numerical values of the similarity criteria determined for the model are identical to the natural loamy soil.

Grass meal is as good as the grain components by its nutritional value, but excels them in nutritional value of protein and vitamins. One kilogram of the grass meal contains 0.7–0.8 feed units, 16–18% of the digestible protein, and up to 30 mg of carotene. During the high-temperature drying of the green material of the perennial grasses, these indices can be increased 1.5–2 times. The heat balance of the unit AVM-0.4 is represented permitting to analyze the possibility to reduce the heat carrier consumption of some processes. The line of the high-temperature drying of the grass in the pseudo-fluidized bed is offered where the optimal conditions of heat transfer and yield of the finished product and its separation into fine and coarse fractions are provided.

A conceptual model for managing productivity of estuary agroameliorative landscapes that makes it possible to take into account the basic parameters of the agroecosystem and the features of the technological process to optimize its operation and to reach a planned level of productivity is presented. The agroecological model that guarantees hay yield at the level of 4–4.5 t/ha is developed for long-term sustainable use of irrigated estuaries with heavy soils. The models are developed for the operation of agroameliorative landscapes and the equations are worked out for correlation dependences of hay yield on the most important factors (contents of humus, phosphorus, and water soluble salts), duration of inundation, and sum of effective air temperatures as applied to the conditions of key segments of estuary irrigation.