Corky root in tomato production

Last changed: 06 December 2023

Management of the soil-borne disease corky root in organic tomato production through the use of compost

Project manager: Paula Persson, Department of Crop Production Ecology, SLU

The idea of this project is to investigate the possibility to suppress corky root through adding composts produced from local on-farm resources. We will study composts from green manure (red clover), horse manure and garden waste and initially test the suppressive effect in a 10-week bio test together with full-scale experiments with tomato plants and Pyrenochaeta.

  • We aim to identify physical, chemical and microbiological parameters that indicate disease suppression by the compost. 
  • We will also study the possibility to strengthen the antagonistic effect of the composts by adding fungivorous nematodes previously studied in vitro and known to have a preference for the corky root fungus. 

The project is a PhD study with MSc Hasna Mahbuba Kaniz as postgraduate student. 


Tomato is the dominant crop in organic greenhouse production in Sweden. The soil-borne disease corky root, caused by the pathogenic fungus Pyrenochaeta lycopersici, is the most serious production problem. In intensive production systems or when the soil is reused for three to four years, the yield reduction can reach 30 to 40%. Earlier research has shown that compost can suppress disease development.