Comparative Study Effect of Urea-Sulfur Fertilizers on Nitrogen Uptake and Maize Productivity.

Combined nitrogen (N) and sulfur (S) fertilization is a good management strategy to reduce N loss and increase the efficiency of N fertilizers to achieve high grain yields and quality. Field trials for 2 yrs. (2018-2019) were conducted to evaluate the comparative advantage of conventional urea (150 N kg ha-1) compared to urea+ ammonium sulfate (150 N kg ha-1), urea+ calcium sulfate (150 N kg ha-1), and urea cocrystals (CaSO4.4urea) (150 N kg ha-1) when applied as nitrogen fertilizers to the maize. The statistics show a significant treatments effect on developed corn cobs, fresh and dry cob yields and grain yield, with 1000 grains with better results in 2019 than in 2018. The fertilization treatments affected grain yields significantly for 2018 and 2019, respectively. Urea+ ammonium sulfate and urea cocrystal provided a significant increase in grain yields by 10.5% and 7.50%, respectively, compared to urea in 2018, w1hereas, in 2019, urea cocrystal supplied the grain yields with a significant increase of 23.07% compared to urea, followed by urea + calcium sulfate which provided a 10.46% increase compared to urea. The study highlights that using urea-sulfur fertilizers enhanced the release of mineral nitrogen in the soil, improved the grain's N uptake by the plant and increased maize grain yields.

The influence of fulvic acid on spring cereals and sugar beets seed germination and plant productivity.

The vegetations and fields experiments were conducted in 2017-2018 at Rumokai Experimental Station of the Lithuanian Research Centre for Agriculture and Forestry. The influence of naturally occurring fulvic acids on the germination of spring wheat and barley and sugar beet seeds, development of plants and their yield and quality was investigated. The use of fulvic acids for seed dressing reliably increased the final germination percentage and decreased the mean germination time in spring wheat, spring barley, and sugar beet. It significantly reduced the number of spring wheat sprouts damaged by Fusarium sp. and the number of spring barley sprouts damaged by Fusarium sp. and Microdochium nivale. Fulvic acids increased the length of spring wheat and barley shoots and the air-dry weight of shoots and roots. The use of fulvic acids during plant vegetation reliably increased spring wheat grain yield and sugar beet roots yield, and improved yield quality. Combinations of fulvic acids with pesticides were also investigated. The use of fulvic acids in combination with pesticides used in sugar beet crops improved the action of those pesticides, so it was possible to reduce the rates used, thus reducing environmental pollution.

Relationship between CO2 emissions and soil properties of differently tilled soils.

Different tillage technologies have different effects on CO2 emissions from soil. Unfortunately, little information exists about the impact of different types of tillage as compared with no-tillage, and the main controls. The aim of this research is to determine the relationship between physicomechanical, chemical and biological properties of soil and CO2 emissions from differently tilled soils under the climatic conditions of central Lithuania before and after autumn tillage. The studies were conducted in 2009-2012 and 2014 at the Experimental Station of Aleksandras Stulginskis University in Central Lithuania. Different tillage technologies were applied: deep ploughing at 23-25 cm depth (DP); shallow ploughing at 12-15 cm depth (SP); deep cultivation with a cultivator at 25-27 cm depth (DC); shallow cultivation with a disc harrow at 12-15 cm depth (SC); and no-tillage (NT). The correlation of physicomechanical, chemical and biological soil properties with CO2 emissions was determined. During all the experimental period total CO2 emissions from soil in DP, SP, DC, SC and NT technologies were respectively 6.05, 4.25, 4.97, 4.42, 3.94 µmol m-2 s-1 before autumn soil tillage and 29.88, 22.50, 16.73, 13.72, 10.00 µmol m-2 s-1 after autumn tillage. Negative correlation between soil temperature and CO2 emissions before the autumn tillage from soil was evidenced (r = -0.98). A strong negative correlation between soil respiration and total soil porosity was observed. Correlation between aeration soil porosity and CO2 emissions was strong. After autumn tillage, the strongest correlations were found between soil penetration resistance and respiration in the upper (r = -0.75) and deeper (r = -0.71) layers. In autumn, a significant strong correlation (r = 0.78) between soil respiration and aeration porosity was obtained in the upper soil layer under ploughing or cultivation. This study revealed that CO2 emissions were significantly higher immediately after autumn ploughing technologies compared to deep and shallow cultivation and no-tillage.