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Legume-supported cropping systems affect environmental, production, and economic impacts. In Europe, legume production is still marginal with grain legumes covering less than 3% of arable land. A transition towards legume-supported systems could contribute to a higher level of protein self-sufficiency and lower environmental impacts of agriculture. Suitable approaches for designing legume-supported cropping systems are required that go beyond the production of prescriptive solutions. We applied the DEED framework with scientists and advisors in 17 study areas in nine European countries, enabling us to describe, explain, explore, and redesign cropping systems. The results of 31 rotation comparisons showed that legume integration decreased N fertilizer use and nitrous oxide emissions (N2O) in more than 90% of the comparisons with reductions ranging from 6 to 142 kg N ha−1 and from 1 to 6 kg N2O ha−1, respectively. In over 75% of the 24 arable cropping system comparisons, rotations with legumes had lower nitrate leaching and higher protein yield per hectare. The assessment of above-ground biodiversity showed no considerable difference between crop rotations with and without legumes in most comparisons. Energy yields were lower in legume-supported systems in more than 90% of all comparisons. Feasibility and adaptation needs of legume systems were discussed in joint workshops and economic criteria were highlighted as particularly important, reflecting findings from the rotation comparisons in which 63% of the arable systems with legumes had lower standard gross margins. The DEED framework enabled us to keep close contact with the engaged research-farmer networks. Here, we demonstrate that redesigning legume-supported cropping systems through a process of close stakeholder interactions provides benefits compared to traditional methods and that a large-scale application in diverse study areas is feasible and needed to support the transition to legume-supported farming in Europe. [ABSTRACT FROM AUTHOR]

In organic farming the control of perennial weed species, in particular Cirsium arvense, can be a major concern for farmers, especially if there is no regulation through perennial forage production. To test whether the stubble cleaner (SC), an enhanced skim plow (PL), is as effective in the control of C. arvense and other weeds as conventional ploughing and perennial forage production, an organic field experiment was established. Three different tillage/crop rotation systems were compared: an SC system and a PL system, both in a cereal-based crop rotation and an additional PL system in a crop rotation that included a perennial alfalfa–grass mixture (PLALF). In the SC system, tillage was carried out solely with the SC, while in the PL and PLALF systems, ploughing was alternated with chiseling. In the fifth year, each main plot was divided into subplots, and seven different cover crop treatments were integrated into each of the three systems. The effects of the three systems and the cover crop treatments on weed cover and density, weed biomass, and weed diversity in the sixth and seventh year of the experiment are the subjects of this paper. The choice of cover crop species was of minor importance for weed control. The PLALF system was generally more effective in controlling C. arvense than the PL and SC systems. No significant differences between the PL and SC systems regarding the control of C. arvense could be identified in four of five assessments. The SC system had significantly higher total weed density than the PLALF and PL systems in both years. However, the differences in weed emergence between the PL and SC systems diminished until the assessment of weed cover and biomass in the main crops, when no significant differences between these two systems (2012) or no differences at all (2013) could be identified. Species richness was not significantly influenced by the tillage/crop rotation system in both years. Evenness and Shannon–Wiener index were significantly higher in the PLALF and PL systems than in the SC system on most assessment dates in 2012. In 2013 there was no clear trend regarding evenness and Shannon-Wiener index probably due to a hoeing operation.. In conclusion, for weed control, the choice of crop rotation was more important than the choice of tillage method, while for the diversity of the weed community, the choice of tillage method was more important than the crop rotation. [ABSTRACT FROM AUTHOR]

Grain legumes are important crops required for protein-rich animal fodder. The aim of this study was to (i) examine the suitability of grain legume cropping systems for cultivation as protein-rich fodder, (ii) compare the performance of winter and spring types of faba beans and peas, as well as to compare the performance of peas sown in pure stand and in mixture with cereals, and (iii) determine the impact of previous legume crop on succeeding wheat under less favorable soil conditions in organic agriculture. In a field trial on a commercial farm in Luxembourg, eight grain legume cropping systems (as given under ii plus soybean and blue lupin) and a non-nitrogen fixing control crop (triticale) were cultivated followed by wheat in two consecutive seasons, employing a randomized complete block design with four replicates. All cropping systems except for winter pea in pure stand, were suitable for cultivation as protein-rich fodder even under less favourable soil conditions. Given sufficient soil moisture, faba beans constituted the best choice (protein yield: 961-1193 kg ha-1). Semi-leafless peas reached a significantly better yield when sown in pure stand (p ≤ 0.05; 3539-4154 kg ha-1) compared with the mixture (2920-3852 kg ha-1), whereas full-leaf types should be cultivated with a cereal partner. Winter vs. spring faba beans did not perform significantly different while for peas, the spring form performed best, likely again depending on leaf type rather than sowing time. The lower previous crop value of mono-cropped cereals (yield first experimental sequence: 2056 kg ha-1) compared with cereals in mixture with grain legumes was confirmed, with best performance of wheat succeeding spring pea in pure stand (first experimental sequence, yield: 3661 kg ha-1). Grain legumes in pure stand exhibited a higher previous crop value than winter triticale or grain legumes grown in mixture. In conclusion, grain legumes were promising candidates for generating protein-rich feedingstuffs, even under less favorable soil conditions in organic agriculture in Luxembourg. [ABSTRACT FROM AUTHOR]