Winter wheat growing in ecological and low-input farming system in term of energy balance

The aim of this study was observation of effect of two different farming systems (ecological and low-input) and two levels of nitrogen fertilization defined according to the regulations valid for water protection zones (Nl - 50% of permissible dose in protected zone of water resources, N2 - full permissible dose in the protected zone of water resources, i.e. 80 kg N per ha) on grain yield, dry matter and selected energy balance traits of winter wheat variety Astella. In years 1999-2002 the stationary field experiment was established on degraded Chernozem on loess (Luvihaplic Chernozem) in a maize-barley growing region in south-western Slovakia (near Piešťany town) with good content of available potassium, normal content of available phosphorus and high content of available magnesium, with the humus content 1.8 - 2.0 %. The area has a continental climate with the average annual temperature 9.2 degree C and means annual precipitation 593 mm. The experimental field crop (winter wheat, variety Astella) which was integrated into six-field crop rotation: - meadow clover (variety Margot); - winter wheat (variety Torysa) + intercrop; - field pea (variety Olivin); - winter wheat (variety Astella); - potato (variety Eta), fertilizing with farm-yard manure + intercrop; - spring barley (variety Atribut) with underseeding meadow clover (variety Margot). In ecological system winter wheat was dressed by commercial compost named Vitahum (producer EBA Bratislava, Slovakia), in low-input system winter wheat was dressed by nitreform of nitrogen. The rates of phosphorus and potassium were determined on the planned grain yield per hectare: 7 tons of winter wheat, 6 tons of spring barley, 4 tons of field peas, 20 tons of potatoes and 10 tons of clover. Besides the yield height dry matter yield, energy input per hectare and per one ton of production, gross energy per hectare, gross energy gain per hectare, per ton of production and per ton of dry matter, energy efficiency, specific energy consumption and energy effectiveness was observed. Obtained results were evaluated by variance analysis. The results show that yield height and practically all studied parameters were strongly affected by year. Higher grain yield of winter wheat variety Astella at average of four years was in low input farming system than in ecological farming system. In term of energy production rate more stabile and more certain is winter wheat growing in low input system in comparison with ecological system, and higher level of nitrogen fertilization (N2) is also preferable. However, in term of energy efficiency, energy effectiveness and specific energy consumption ecological farming system and lower level of nitrogen fertilization (Nl) appears to be more favourable. Ecological farming system and lower level of nitrogen fertilization has besides production aspect more positive effect on environment. This fact is very hardly quantified but it is important for a good and healthy life. Our results show that both farming systems of winter wheat can be advised for practice, but in term of energy production rate more certain is winter wheat growing in low input farming system. Ecological farming systems have positive effect on living environment.