• Energy Research

Sustainable cropping systems require efficient usage of fossil energy. This study performed on a long-term field experiment in the Pannonian Basis investigated the energy efficiency of four tillage systems (mouldboard plough (MP), deep conservation tillage (CTd), shallow conservation tillage (CTs) and no-tillage (NT)) for sugar beet and soybean production, taking fuel consumption, total energy input (made up of both direct and indirect inputs), crop yield, energy output, net-energy output, energy intensity and energy use efficiency into account. The input rates of fertiliser, chemical plant protection, and seeds were set constant across years; whereas measured values of fuel consumption were used for all tillage treatments. NT required a considerably lower energy input than MP and CTd as no fuel is needed for tillage and just slightly more fuel for additional spraying of glyphosate. Anyhow, the energy efficiency parameters did not differ between tillage treatments, as theses parameters were mainly determined by energy output, which was considerably higher than the energy input. However, year effects on the energy efficiency were observed for both crops. Nitrogen fertilisation and diesel fuel consumption were identified as the most energy-intensive inputs. Consequently, the energy input for sugar beet was higher than that for soybean, which was identified as a low-input crop. But sugar beet attained a more than 4 times higher net-energy output, a 2.5 times higher energy use efficiency, and an energy intensity for yield production of less than 3 times those of soybean.

Poppy cultivation has a long tradition in Central Europe. Growing winter poppy instead of the commonly grown spring poppy might increase seed yield, especially in the face of changing climatic conditions. However, knowledge regarding optimum sowing date and optimum sowing rate for winter poppy under Pannonian climate conditions in Central Europe is missing. Therefore, a two-year field experiment was performed in Eastern Austria with four sowing dates ranging from early September to mid/end of October and two sowing rates with 50 or 100 mg seeds m−2. Seed yields were considerably higher than values reported for spring poppy throughout all sowing dates, mainly due to a higher number of seeds capsule−1 and, thereby, a higher seed yield capsule−1. The highest seed yields were obtained by sowing in early October, while the earliest and especially the latest sowing date resulted in lower seed yields. Consequently, the optimum sowing date for winter poppy under Pannonian climate conditions in Central Europe is early October but sowing can be performed over a wider range of dates. No seed yield differences were observed between sowing rates. Consequently, the sowing rate can be much lower than the recommended sowing rate for spring poppy.

This study analyzed energy input (direct and indirect), energy output, net-energy output, energy use efficiency, energy intensity, and the energy productivity of oat:pea intercrops as affected by sowing ratio (oat:pea (%:%): 100:0, 75:25, 50:50, 25:75, 0:100) and nitrogen (N) fertilization (0, 60, 120 kg N ha−1). The two year field experiment was conducted on a calcaric Chernozem soil in the north-western part of the Pannonian Basin. The results for grain yield showed that pure stands of oat and pea had a higher energy use efficiency and energy intensity than intercrops, indicating that pure stands used the growing factors more efficiently than intercrops. The energy use efficiency was higher in pure pea than pure oat. The energy productivity for the above-ground biomass production was much more affected by the factor N fertilization than by the factor sowing ratio. The highest energy productivity of grain N yield and above-ground biomass N yield was achieved in pure pea stands (0:100). N in plant residues of the zero N fertilization variant required 68% lower technical energy than N from mineral fertilizer. The sowing rate of the intercrops is a management tool to trade-off between the benefits of the in-field biodiversity and energy efficiency.

Sustainable crop production requires an efficient usage of fossil energy. This six-year study on a silt loam soil (chernozem) analysed the energy efficiency of four tillage systems (mouldboard plough 25-30 cm, deep conservation tillage 35 cm, shallow conservation tillage 8-10 cm, no-tillage). Fuel consumption, total energy input (made up of both direct and indirect input), grain of maize yield, energy output, net-energy output, energy intensity and energy use efficiency were considered. The input rates of fertiliser, herbicides and seeds were set constant; measured values of fuel consumption were used for all tillage operations. Total fuel consumption for maize (Zea mays L.) production was 81.6, 81.5, 69.5 and 53.2 L/ha for the four tillage systems. Between 60% and 64% of the total energy input (17.0-17.4 GJ/ha) was indirect energy (seeds, fertiliser, herbicides, machinery). The share of fertiliser energy of the total energy input was 36% on average across all tillage treatments. Grain drying was the second highest energy consumer with about 22%. Grain yield and energy output were mainly determined by the year. The tillage effect on yield and energy efficiency was smaller than the growing year effect. Over all six years, maize produced in the no-tillage system reached the highest energy efficiency.

The long cultivation of field pea led to an enormous diversity which, however, seems to hold just little resistance against the ascochyta blight disease complex. The potential of below ground microbial symbiosis to prime the immune system of Pisum for an upcoming pathogen attack has hitherto received little attention. This study investigates the effect of beneficial microbes on the leaf proteome and metabolome as well as phenotype characteristics of plants in various symbiont interactions (mycorrhiza, rhizobia, co-inoculation, non-symbiotic) after infestation by Didymella pinodes. In healthy plants, mycorrhiza and rhizobia induced changes in RNA metabolism and protein synthesis. Furthermore, metal handling and ROS dampening was affected in all mycorrhiza treatments. The co-inoculation caused the synthesis of stress related proteins with concomitant adjustment of proteins involved in lipid biosynthesis. The plant's disease infection response included hormonal adjustment, ROS scavenging as well as synthesis of proteins related to secondary metabolism. The regulation of the TCA, amino acid and secondary metabolism including the pisatin pathway, was most pronounced in rhizobia associated plants which had the lowest infection rate and the slowest disease progression.A most comprehensive study of the Pisum sativum proteome and metabolome infection response to Didymella pinodes is provided. Several distinct patterns of microbial symbioses on the plant metabolism are presented for the first time. Upon D. pinodes infection, rhizobial symbiosis revealed induced systemic resistance e.g. by an enhanced level of proteins involved in pisatin biosynthesis.

SummaryCover cropping is a key agro-environmental measure in Europe. Cover crops may reduce N2O emissions by reducing soil nitrate content, while easily decomposable residues can enhance greenhouse gas losses. In a field study, emissions from the cover cropped fields compared to the fallow at two climatically different sites (semi-arid vs. humid) in Austria were measured with closed chambers and different driving factors were studied. The height of post-cover crop emissions was compared to gaseous losses during the management operations in the subsequent main crop maize. N2O and CO2emissions following the cover crops were low even at high emission moments compared to the losses induced by the main crop management operations. Highest risk of N2O losses was from mustards due to low C/N ratio and possibly as a consequence of glucosinolate decomposition. CO2emissions in the cover cropped plots were generally higher compared to the fallow, indicating an enhanced soil microbiological activity. Dissolved organic carbon was found as a sensitive indicator related to the greenhouse gas emissions. We concluded that the environmental benefits from cover cropping are not achieved at the cost of an enhanced greenhouse gas emission and that pure stands of late sown brassica cover crops should be avoided to prevent any risk of increased N2O losses.

Abstract 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.

The effect of crop sequences (CR - continuous winter rye; CropR - three-field crop rotation of winter rye-spring barley-bare fallow) and fertilisation systems (unfertilised control, mineral fertiliser (NPK), farmyard manure (FYM)) on crop yield, energy efficiency indicators and land demand were analysed in a long-term experiment under Pannonian climate conditions. Due to lower fuel consumption in the bare fallow, the total fuel consumption for CropR was 27% lower than in CR. It was for NPK and FYM fertilisation by 29% and 42% higher than in the control. Although the energy output was lower in CropR than CR, the energy use efficiency for grain production increased by 35% and for above-ground biomass production by 20%. Overall crop sequences, the NPK treatment had higher crop yields, energy outputs and net-energy output with a lower energy use efficiency than the unfertilised control. CropR increased the land demand just by 20% in comparison to CR, although one-third of the land was not used for crop production. The land demand could be decreased with fertilisation by 50% (NPK) or 48% (FYM). A bare fallow year in the crop rotation decreased the crop yield, energy input and increased the energy use efficiency and land demand.