Energy efficiency of winter wheat in a long-term tillage experiment under Pannonian climate conditions

One goal in sustainable agriculture is to use fossil energy more efficiently in crop production. Information on energy consumption and efficiency of different soil tillage systems for developing energy-efficient farming systems with reduced impact on climate change is missing for the Pannonian Basin. This 12-year study on a silt loam chernozem investigated the energy efficiency of four tillage systems (mouldboard plough (MP), deep conservation tillage (CTd), shallow conservation tillage (CTs), no-tillage (NT)) in rotations taking thereby into account diesel fuel consumption, total energy input (made up of both direct and indirect inputs), grain yield, energy output, net-energy output, energy intensity and energy output/input-ratio. Input rates of fertilizer, herbicides and seeds remained constant, while values of diesel fuel consumption were measured for all tillage operations. Total diesel fuel consumption for winter wheat (Triticum aestivum L.) production was 59.8 L ha−1, 60.6 L ha−1, 48.5 ha−1 and 36.0 L ha−1 for MP, CTd, CTs and NT, respectively. Between 73% and 83% of total energy input was required by indirect energy (seeds, fertilizer, herbicides, machinery). MP and CTd each required a total energy input of about 9.3 GJ ha−1; the total energy input for CTs and NT was lower by 4.8% for both. Direct energy input (diesel and lubricant oil) was much lower with no-tillage (with 1.5 GJ ha−1) than with mouldboard plough (with 2.4 GJ ha−1), deep conservation tillage (with 2.5 GJ ha−1) and shallow conservation tillage (with 2.0 GJ ha−1). Grain yield and thus energy output were mainly influenced by year. The year effect on yield and energy efficiency parameters was larger than the tillage effect. Especially in dry years, ploughless tillage systems tended to respond with competitive yields. This resulted in an increase of energy efficiency parameters. Over all twelve years, winter wheat produced in the CTs tillage system reached the highest net-energy and output/input-ratio with the lowest energy intensity.