Disease control in organic tomato production – combined biological control with microorganisms and biofumigation
In organic tomato production, soil-borne plant diseases are one of the main yield reducing factors. Two of the most problematic diseases are the corky root disease, caused by Pyrenochaeta lycopersici, and fusarium crown and root rot, caused by Fusarium oxysporum f.sp. radicis-lycopersici.
These pathogens are producing resting structures in the soil, and their control is difficult since the soil cannot be sanitized between crop cultures - existing methods such as changing the soil, soil fumigation or heating are problematic and also restricted due to rules for organic production, costs, energy consumption and working safety requirements.
Biological control in organic tomato production
Therefore, we will evaluate the potential of biological control agents (BCAs) already available on the Swedish market or in the development process, and soil amendments that can sanitize the soil and stimulate naturally occurring soil organisms with antagonistic activity against plant pathogens.
Although the interest for such methods to control diseases is high, the current use is limited. The variation among soils leads to differences in efficacy of BCAs and in the way the soil microbial communities respond to additions of organic material. Increased understanding about this variation and how the control measures can be adjusted depending on the soil will increase the potential for successful biological control in soil-based plant production systems.
To give new recommendations
A range of soils from Swedish tomato growers will be investigated concerning the ability of (BCAs) to colonize the soil and control soil-borne diseases, alone or following addition of organic material. The results will be of direct importance for organic tomato production, and the in depth findings are of interest for biological control of plant diseases in all types of soil-based plant production systems.
- Christoffer Berner, Department of Forest Mycology and Pathology/Centre for Biological Control, SLU
- Hanna Friberg, Department of Forest Mycology and Pathology/Centre for Biological Control, SLU
- Anna Mårtensson, Department of Soil and Environment
- Birgitta Rämert, Department of Plant Protection Biology, SLU
- Associated partner: Elisabeth Ögren, advisor for vegetable production at Länsstyrelsen Västmanland
This project is financed by SLU EkoForsk.