EVALUATION OF THE INITIAL MATERIAL OF THE FESTULOLIUM FOR THE STEPPE CONDITIONS OF THE CENTRAL CHERNOZEM REGION

In recent decades, a new feed crop, festulolium, has been widely used in the feed production of Russia. In this regard, an important task is the permanent creation of a line of festulolium varieties that ensure high efficiency of using this crop in various climatic and ecological conditions. The article presents the material on the assessment of the initial material of the festulolium in the steppe conditions of the Central Chernozem region.

Nitrogen deposition enhanced productivity of sweet sorghum (Sorghum bicolor L.) in the arid region of China

<p>Terrestrial ecosystems worldwide are experiencing increasing atmospheric nitrogen (N) deposition because of fossil-fuel combustion and fertilizer applications. As a C<sub>4</sub> feed crop, sweet sorghum (<em>Sorghum bicolor L.</em>) is widely used in the arid region of China since its high sugar content, good palatability and high yield. However, impacts of atmospheric N deposition on production of sweet sorghum are poorly understood in arid land ecosystems where soils are typically low in plant available N. At Hui Autonomous Region, Ningxia, China, a complete random block design was used to study the effects of four levels of N additions (45, 169, 197, and 224 kg ‍‌‌‍ha<sup>-1</sup> year<sup>-1</sup>) on sorghum, node number, stem diameter, leaf number, plant height, yield per plant, dry matter, and sugar Brix of stem. Nitrogen application significantly affected the above parameters. When the amount of N applied was 224 kg ‍‌‌‍ha<sup>-1</sup> year<sup>-1</sup>, the plant height (mean ± standard deviation, 256.9 cm ± 10.7, n=9), stem diameter (16.9 mm ± 1.1 ,n=9), number of leaf (10.8 ± 1.3, n=6) and node (4.9 ± 0.4, n=9), and dry matter per unit area (1.48 t ha<sup>-1</sup> ± 0.3, n=9) was highest. While N application did not affect sugar Brix of stem. Therefore, N deposition plays a linearly positive role in enhancing the productivity of sweet sorghum in the arid region of China.</p><p>Keywords: Agronomic traits, C<sub>4</sub> plant, Feed crop, Nitrogen addition</p>

Agrogenic evolution of organic matter in peat soils of Western Siberia

The influence of the groundwater level (GW), vegetable crop rotation and mineral fertilizers on the change in the composition of organic matter of medium-thick peat soil was determined. The study was conducted on lysimeters with an adjustable level (0.5; 1.0; 1.5 and 1–2.0 m) of groundwater occurrence; in a vegetable-feed crop rotation spread in time and space; under perennial grasses without prior cultivation of annual crops. It was established that in the arable layer (0.2 m) of peat soil, the bitumen content at GW level of 0.5 m was lower by 1.65% than at a depth of 1.0 m, and by 4.34% than at a depth of 1.5 m. The maximum amount of water-soluble substances (5.68%) and substances hydrolyzable by 2% HCl (34.25%) was established at GW level of 0.5 m. It was 1.2 and 3.4–3.8% higher than at groundwater level of 1–1.5 m, respectively. With GW level of 1.5 m, the amount of humic acids decreased by 4.5% compared to their occurrence at a depth of 0.5 m. The amount of fulvic acids in the arable layer depends on the GW level (r = 0.79). The content of substances hardly hydrolyzable by 80% H2SO4 in the arable layer decreased from 2.82 to 2.31% with an increase in groundwater depth from 0.5 to 1.5 m. It was observed that the amount of lignin decreased with an increase in groundwater depth from 0.5 (6.66%) to 1.5 m (5.30%). Five- year cultivation of crops in the vegetable-feed crop rotation did not lead to significant changes in the composition of the organic matter of peat. Grassing of peat soils with perennial grasses without sowing pre-crops ensures preservation of peat organic matter and prevents its substantial transformation. Mineral fertilizers reduce the rate of accumulation of hardly-hydrolyzable and non-hydrolyzable forms due to more severe oxidative-hydrolytic conditions in the soil and because of an increase in the amount of fresh plant material as a result of crop and root residues.

Ecological adaptivity of grass swards with inclusion of festulolium in the conditions of the Republic of Karelia

An assessment of the environmental adaptability of a promising feed crop - festulolium as a part of two-component and three-component grass swards mixtures was made in the conditions of the Republic of Karelia. Based on the results of ten years of research, parameters of plasticity and stability of dry yield weight have been determined by calculating the regression coefficient (bi) and the standard deviation (Si2). All studied grass stands are characterized as highly plastic (bi equal to or close to 1) and stable (Si2 tends to zero): crop productivity increases at a high soil fertility and is relatively uniform in different environmental conditions.