Landbauforschung - Journal of Sustainable and Organic Agriculture

Editorial

Hella Kehlenbeck — 2024-01-22

Editorial

Potential of pesticide reduction and effects on pests, weeds, yield and net return in winter rye (Secale cereale L.)

Bettina Klocke — 2024-01-18

Reducing the intensity of pesticide use is a societal and political issue. One way to realize this is to reduce the dose of applied pesticides. The impact of strict dose reductions on yield and net return in winter rye was examined in a longterm field trial at the experimental field of the Julius Kühn Institute in Dahnsdorf (Brandenburg) over a 13-year period (2004-2016). Pesticide treatments included a situation-related strategy (100% strategy) and two other strategies in which the doses were reduced by 25% and 50% compared to the 100% strategy. Treatment decisions were based on control thresholds in the 100% strategy. Fungal pathogens and weeds occurred in all years and had to be controlled. Insect pests were negligible. Averaged over all years, there was a significant difference of 4% in yield between the 100% strategy and the 50% strategy. In contrast, no differences were found in terms of net return. There was also no accumulation of weeds in the reduced strategies. This positive result is due to the close monitoring of the plots as well as the six-year crop rotation and shows that it is possible to reduce pesticide use in winter rye.

Assessing pollen beetle dynamics in diversified agricultural landscapes with reduced pesticide management strategies

Emily Dovydaitis — 2024-01-22

The European Farm to Fork strategy strives to reduce pesticide use and risk by 50% by 2030, preserving agricultural productivity, biodiversity, and human health. Novel research on crop diversification and new field arrangements, supported by digital technologies, offers sustainable innovations for pest control. This study evaluates digital yellow water traps, equipped with a camera and associated artificial intelligence model for continuous pollen beetle monitoring in diversified agricultural landscapes. Data were collected in oilseed rape from three harvest years (2021-2023) at the experimental site patchCROP, a landscape experiment established to study the effects of spatial and temporal crop diversification measures on yield, ecosystem services, and biodiversity. In patchCROP, crops were planted in smaller, 0.5 ha (72 × 72 m) squares called "patches" with different pesticide management strategies and were compared to surrounding commercial fields. The digital yellow water traps and AI were evaluated and found to be useful for gauging pollen beetle immigration into the crop. Across all years, higher insect pest pressure was recorded in the patches compared to commercial fields but did not necessarily compromise yields. Implementation of pesticide management strategies, including targeted insecticide applications at specific insect pest thresholds, were not associated with reduced yields in patches with flower strips. Future studies should consider examining the role of field size and alternative diversification approaches to fine-tune insecticide reduction strategies at the landscape scale.

Costs and benefits of preventive strategies to reduce pesticide use

Jovanka Saltzmann — 2024-01-18

Plant pests, diseases and weeds threaten agricultural crops and require control methods. However, the largely used pesticides are associated with undesirable effects on environment and health. To reduce pesticide use, Integrated Pest Management (IPM) offers a comprehensive toolbox. The two selected IPM strategies (1) wide crop rotation and (2) cultivation of pathogen resistant cultivars were analysed economically based on two different field trials. Crop rotation (long-term field trial at Dahnsdorf, Brandenburg, Germany, with a sixunit crop rotation) and pesticide reduction by 25% and 50% resulted in no decline in gross margins and thus profitability in silo maize, wheat (E- and A-quality), barley and rye. However, a 25% and 50% reduction in pesticides led to a decline in gross margins by -6.3% (-331 € ha^-1) and -8.3% (-437 € ha^-1) in potatoes. The use of pathogen resistant wheat cultivars and IPM based fungicide application (tested at five field sites across Germany) resulted in reduced fungicide applications and higher gross margins compared to the “non-IPM” strategy by about +45 to 70 € ha^-1. Based on these findings, we conclude that preventive IPM strategies have a good potential to reduce pesticide use and are also economically viable for farmers.

Yield Potential of Cropping Systems without Chemical Synthetic Plant Protection Products in NOcsPS field trials in Germany

Ingrid Claß-Mahler — 2024-01-18

In endeavors to manage agricultural cropping systems without the application of chemical-synthetic plant protection products (CSPs), one of the greatest challenges is ensuring yield performance. The literature provides a wealth of data on organic farming yields and the gap between organic and conventional systems, but little knowledge on the yield performance of cropping systems that use mineral fertilizers but not CSPs. This paper presents the first results of field trials at two locations in Germany comparing cultivation systems that are free of chemical-synthetic plant protection, but use mineral fertilizers, with both conventional and organic cropping systems. These system trials are part of the joint research project "Agriculture 4.0 without chemical-synthetic plant protection (NOcsPS)". Initial results show that CSP-free cultivation systems generally achieve lower yields than conventional systems, but considerably higher yields than organic systems.

Factors influencing the acceptance of pesticide-free farming systems by farmers

Marius Jahnke — 2023-12-21

Pesticides have been an integral part of modern agriculture, aiding farmers in their fight against pests and increasing crop yields (Damalas, 2009). However, the widespread use of pesticides has resulted in numerous negative consequences, including environmental degradation, health hazards and increased resistance among pest populations (Godfray et al., 2010; Hawkins et al., 2019; Powles & Yu, 2010; Riyaz et al., 2022). In particular, pesticide residues in food are becoming an increasingly critical issue for consumers (Nitzko et al., 2022). As a result, there has been a growing interest in pesticide-free farming practices that focus on natural methods of pest control as for instance established in organic farming approaches (Stehle & Schulz, 2015).
Agriculture without synthetic chemical pesticides is a new concept in plant cultivation with the aim of achieving the highest possible yields through the use of mineral fertilisers while at the same time reducing environmental impacts by avoiding the use of chemical plant products (Zimmermann et al., 2021). By avoiding pesticides entirely, this concept has the potential to make a significant contribution to the reduction of pesticides targeted by the EU and to avoid the problems of pesticide residues in food and loss of biodiversity. However, the adoption of pesticide-free farming is still limited (Christensen et al., 2011; Finger & El Benni, 2013; Möhring & Finger, 2022). In this context, pesticide-free agriculture is understood as more than the mere substitution of chemical plant protection measures by non-chemical (e.g. technical) measures. Rather, pesticide-free agriculture is a system-level approach that aims to redesign the farming system to incorporate both new technologies and agroecological practices (Jacquet et al., 2022; Zimmermann et al., 2021). Comprehensive information on the drivers, barriers and challenges faced by farmers is needed for the widespread uptake of pesticide-free farming systems.
In this paper, we examine the acceptance of pesticide-free farming from the farmers' perspective. Specifically, we investigate the factors that influence farmers' decision-making regarding the adoption of pesticide-free farming practices and the challenges they face. We also explore the role of knowledge and experience in shaping farmers' acceptance of pesticide-free farming. In addition, we are evaluating possible scenarios for the implementation of pesticide-free farming systems. To do this, we use a qualitative approach, interviewing both conventional farmers and farmers who already farm partially without pesticides.
The research paper is part of the research project Agriculture 4.0 without chemically synthetic pesticides. Through our research, we aim to provide insights into the factors that influence the acceptance of pesticide-free farming practices among farmers. We hope that our findings will inform policy decisions and promote the adoption of sustainable farming practices that benefit both farmers and the environment.

Claim preferences of consumers for vegetables from pesticide-free agriculture: a survey experiment

Sina Nitzko — 2024-01-18

Sustainable consumption decisions can be promoted by claims on food. It is essential that the claims are consumeroriented. In this light, the consumer evaluation of different labelling variants for pesticide-free vegetables was recorded for three claims on the pesticide renunciation and four claims on sustainability-related consequences of the pesticide renunciation. An online survey was conducted with 953 German consumers. Each participant was randomly assigned to one of seven subsamples. Each subsample evaluated one of seven claims. The evaluations show that all claims were rated as “moderately” to “quite understandable” and appropriate to the cultivation form and would “perhaps” to “quite probably” be helpful in the purchase decision. Further, the claims on pesticide renunciation were perceived as more understandable, more appropriate for the cultivation form and more helpful for the purchase decision compared to the claims on sustainability-related consequences. The findings are useful for actors in the agricultural and food sector.

Reduction of plant protection products in sensible areas in Germany in context of the SUR Proposal

Burkhard Golla — 2024-01-25

In agriculture, the application of plant protection products to cropland is important to prevent quality and yield reduction. The use of plant protection products implies negative effects on human health and the environment. Thus, a legal measure towards reducing the use of plant protection products is its restriction or ban especially in sensitive areas.
This is the first national study to use publicly and freely available geodata to access the area of agricultural land located in different types of sensitive areas according to the proposal for a new EU Regulation on the Sustainable Use of Plant Protection Products (SUR). We assess the impact of different scenarios for a German implementation. In this study we analyse publicly available geodata of CORINE land cover 5 ha of 2018 with geographic information systems (GIS) for different scenarios.
The results show that the impact of a pesticide ban or restriction for sensitive areas differs between regions and the type or combination of sensitive area. Using the CLC5-2018 data we estimate 19.6 million hectares of national agricultural area. Landscape Protection Area, Nature Parks and Water Protection Areas contain the largest proportion of agricultural land. A scenario which considers National Parks, Nature Reserves, Biosphere Reserves, Nature Parks, Natural Monuments, Landscape Protection Areas and Natura 2000 sites with Fauna-Flora-Habitat areas and Special Protected Areas for bird sanctuaries and Ramsar sites would affect 46.6% of the agricultural land use in Germany, ranging from 33.4% to 77.9% across different states.
Comparing our CLC5-2018 results to a similar study from 2023, which used LBM-DE as land use data, we find that there is little difference between the results of identical scenario definitions when expressed as proportions. Whereas different SUR scenario definitions can lead to significantly different outcomes.