PART 1. A FEW DEFINITIONS

1. Pest, crop protection and natural regulation

•Pest: from injuries to economic losses

•Natural regulation in crop protection strategies

2. Plant diversification in agricultural areas

•Increasing crop intraspecific diversity: varietal mixtures, use of heterogeneous varieties (farmer, traditional), etc.

•Increasing the interspecific diversity of the cultivated cover: mixed cropping, service plants, agroforestry, etc.

•Increasing the temporal diversity of cultivated plants: diversified rotations

•Diversity of semi-natural vegetation in the landscape: hedgerows, permanent grasslands, groves, etc.

•Managing the level of diversity in the landscape

PART 2. LESSONS LEARNED FROM THE COLLECTIVE SCIENTIFIC ASSESSMENT

3. Agroecological impacts of plant diversification

•Diversifying the vegetation on agricultural fields and landscapes is a crop protection lever

•Plant diversification is good for the associated biodiversity and the ecosystem services provided to farmers and society

•Diversified systems often provide higher yields than poorly diversified systems

4. Implementing plant diversification to protect crops

•Introduction

•Plant diversification has contrasting effects on short-term farm profitability

•To encourage plant diversification, several obstacles must be removed both within agricultural supply chains and at the territorial level

•Public policies are a key factor in the deployment of plant diversification

PART 3. OUTLOOK AND RESEARCH NEEDS

5. Perspectives: plant diversification and environmental challenges

•What role can plant diversification play in the transition to pesticide-free agriculture?

•Plant diversification of agricultural systems to meet the challenges of climate change

•To what extent should we diversify? Some recommendations from the scientific literature

6. Further research and studies needed

•Gaining a better understanding of the natural regulation mechanisms of pests

•Gaining a better understanding of socio-economic organisations

•Building on long-term research and using digital tools…

•… to design public policies that foster diversification

Conclusion

Annex. The turning point in the Common Agricultural Policy that paved the way for plant diversification

•Greening the 2014 reform: An admission of failure?

•The promises of the post-2020 CAP reform

Selected references

Composition of the working group

Image and photo credits