Which measures are suitable for significantly reducing pesticide use in field crops? In the PestiRed project, farmers rate the implemented measures as largely positive; with a differentiated result for economic efficiency.
The PestiRed project aims to significantly reduce the use of chemical plant-protection products (PPPs) in field crops via the systematic application and further development of integrated pest management. The target is to reduce plant-protection product use by 75% with a maximum 10% decline in economic efficiency.
PestiRed is sponsored as part of the Federal Office for Agriculture’s resources programme. Sixty-seven farms in the Cantons of Geneva (GE), Vaud (VD) and Solothurn (SO) are involved in the project. The project is supported by IP-SUISSE, the agricultural offices of the Cantons of SO, VD and GE, as well as agricultural extension organisations.
Survey of the participating farmers
The farmers involved in the project are surveyed annually once the growing season is over in order to test the acceptance of and refine the measures. The results of the surveys for the first two growing years, 2019–2020 (harvest year 2020) and 2020–2021 (harvest year 2021) are now available.
All farmers participating in the PestiRed project implement five basic measures:
- More-resistant varieties
- Adapted nitrogen use
- Optimised sowing
- Control thresholds and forecasting systems
- Drift minimisation
Besides this, the farms can choose further specific measures.
The measures are divided into four areas:
A – Reduction of initial harmful organisms (preventive)
B – Prophylactic measures (preventive)
C – Non-chemical control (curative)
D – Chemical control (curative)
The expenditure for implementing these measures (machinery costs, labour, seed) is reimbursed via the PestiRed ressources programme.
Herbicide reduction measures rated most positively
The farmers overwhelmingly rate the alternative plant-protection measures as ‘fairly positive’ or ‘positive’ in terms of their potential for reducing chemical plant-protection use (Tab. 1). Individual measures lie in the ‘neutral-to-fairly-positive’ range.
Non-chemical control measures are perceived by the farmers as relatively effective for reducing the use of chemical PPPs. Measures that reduce herbicide use are rated most positively. Mechanical weed control in particular is deemed effective for saving on herbicides.
The basic measures ‘variety selection’ and ‘control thresholds’/‘forecasting systems’ occupy the upper middle range. Measures from areas A (‘reduction of initial harmful organisms’) and D (chemical control, e.g. ‘subarea treatment’ and ‘drift-reducing PPP techniques’) are also perceived as comparatively effective.
Companion planting, optimisation of sowing and nitrogen use, variety mixtures, and (in particular) flower strips for beneficials were viewed as less effective, but still having a positive effect in terms of their potential for reducing PPP use.
Tab. 1: Rating of the measures according to their potential for reducing PPP use (PPP Reduction, in descending order) and their economic efficiency. Averages of a 7-point scale are shown, from 1 = very negative, 4 = neutral up to 7 = very positive. Only measures with at least 10 responses (N) are listed.
Economic efficiency rated more critically
Despite the measure-specific project contributions that are meant to offset the additional costs, the economic efficiency of the measures is rated more critically by the farmers. With one exception, economic efficiency is rated lower in each case than PPP-reducing potential (Tab. 1). The economic efficiency of a production process and of the applied measures depends on the performances achieved as well as the costs. The latter are for the most part rated fairly negatively.
Rating the areas of intervention
Comparing the four areas of intervention in terms of their ratings for reducing the use of plant-protection products, the following ranking emerges:
- Non-chemical methods
- Measures for reducing initial harmful organisms
- Chemical control
- Prophylactic measures.
For economic efficiency, the ranking is the exact reverse.
Optimising measures together with project partners
The interim results of the PestiRed project are meant to support the co-innovative nature of the project. Cooperation and exchange between practice, extension and research is intended to optimise existing measures and develop new alternative measures.
- Non-chemical control methods are perceived by the farmers as relatively effective in reducing PPP use. In particular, methods for saving on herbicides, such as mechanical weed control, are rated positively in terms of their reduction potential.
- Despite direct payments and measure-specific contributions from the project, economic efficiency is rated as neutral and in some cases fairly negative.
- Certain preventive measures such as the choice of resistant varieties, the application of control thresholds and forecasting systems or optimised intercropping are rated as fairly good both in terms of their PPP-saving potential and their economic efficiency.
- The higher the effectiveness rating of the areas of intervention in terms of their potential for reducing PPP use, the lower their average rating for economic efficiency.