Why It Matters
Soil health is foundational to sustainable agriculture, influencing crop productivity, environmental quality, and long-term farm viability. This project addresses the need for tailored crop rotation systems in the Eastern Free State, focusing on dryland potato and summer grain production. By integrating cover crops and evaluating their impact on soil microbial, chemical, and physical properties, the study promotes practices that enhance soil resilience and suppress crop pathogens. The findings offer region-specific insights that support more sustainable and profitable farming systems, benefiting producers and the broader agricultural industry.
Research Approach
This long-term study evaluates crop rotation systems over nine years, comparing fallow and cover crop treatments across multiple rotations. Soil samples are analyzed mid-season for microbial functionality (using Biolog EcoPlates), respiration (CO₂ release), and microbial diversity (DNA-based analysis of bacterial and fungal communities). Enzyme activity and soil chemical properties are also assessed. The project tracks seasonal changes and functional diversity to understand how different crop sequences influence soil health. Data is collected from replicated field trials and interpreted to guide optimal rotation strategies for the region.
Research Impact to Farmers
Farmers in the Eastern Free State and beyond benefit from practical, science-based recommendations for crop rotation planning. The study identifies crop combinations that improve soil health and suppress pathogens, enhancing productivity and reducing input costs. Cover crops, in particular, show promise for boosting microbial activity and soil resilience. These insights help producers make informed decisions about rotation schedules, contributing to long-term sustainability and profitability. The research also supports broader industry goals by promoting ecological farming practices and improving the viability of dryland potato and grain systems.
Resources
Articles:
- Doran & Zeiss (2000). *Soil health and sustainability*
- Larkin & Griffin (2007). *Control of soilborne potato diseases using Brassica green manures*
- Snapp et al. (2005). *Evaluating cover crops for benefits, costs and performance
Collaborators & Research Leads
Lead Researcher:
- Prof JM Steyn (University of Pretoria)
Collaborative Institutions:
- University of Pretoria (UP)
- Agricultural Research Council – Vegetable and Industrial Crops (ARC-VIMP)
- Potatoes South Africa
- Grain SA
Key Contributors:
- Ms Taryn Armfield (UP)
- Dr Elsie Cruywagen (ARC-VIMP)
- Prof Quenton Kritzinger (UP)