Wheat is one of the most widely distributed crops worldwide and is of primary importance as food for human nutrition. Increasing the productivity of the new wheat varieties according to the specific climate of the region is a permanent major task. The impact of environment and some agronomy practices (previous crop and mineral fertilization) on the productivity and the structural elements of yi...

nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertilization and soil cultivation practices were studied. field trial was conducted in the institute of forage crops, pleven, bulgaria on leached chernozem subsoil type and no irrigation. the next treatments were tested: i) for fertilization as follows: n0p0k0 (control); n60p100k80 (an accepted technology...

The effect of different systems of N fertilization on nitrogen balance and N transformation in the soil was studied in long-term stationary experiments (1991–2002) with successive growing of maize. Average dry matter yield for the control without fertilization in the period 1991–2002 was 11.67 t of dry matter per ha, which was by 2–2.9 t less than for fertilization treatments. Statistically sig...

The purpose of this study was to examine: 1) whether caffeine in the fertilization medium under mineral oil is essential for bovine in vitro fertilization by fully capacitated spermatozoa, 2) the minimum concentration of caffeine that shows an adverse effect on the motility of preincubated spermatozoa. Cumulus-oocyte complexes with heterogeneous-appearing ooplasm were matured in in vitro cultur...

The pool of soil organic carbon (SOC) in the Arctic is disproportionally large compared to those in other biomes. This large quantity of SOC accumulated over millennia due to slow rates of decomposition relative to net primary productivity. Decomposition is constrained by low temperatures and nutrient concentrations, which limit soil microbial activity. We investigated how nutrients limit bacte...

Physiological investigations of nitrogen content and relation between nitrogen and chlorophyll content at some wheat cultivars were carried out at the outset of the flowering phase. Dependence of nitrogen content from mineral elements in the soil was established at the same time. Investigations were guided on unfertilized soil and four fertilization variants (N, NPK, NP and NK). The results ind...

Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertilization and soil cultivation practices were studied. Field trial was conducted in the Institute of Forage Crops, Pleven, Bulgaria on leached chernozem subsoil type and no irrigation. The next treatments were tested: i) for fertilization as follows: N0P0K0 (control); N60P100K80 (an accepted technology...

Supplying mineral nutrients at the proper rate and in the proper balance has a major effect on seedling growth rate but, more importantly, on seedling quality. In addition, mounting concerns about fertilizer pollution are increasing awareness of the benefits of precision fertilization. Because they reflect actual mineral nutrient uptake, plant tissue tests are the best way to monitor a fertiliz...