Optimization of solarization and steaming to eradicate TMV from cocopeat

This collaborative study by TECNOVA (Spain) and Landwirtschaftskammer Nordrhein-Westfalen (Germany) within the VIRTIGATION project evaluates solarization and steaming for eradicating Tobacco Mosaic Virus (TMV) from contaminated cocopeat. Solarization using 37.5 µm polyethylene film over 60 days (Sept–Nov) achieved temperatures up to 46.2 °C, with all tomato plants in treated bags remaining symptom-free; PCR detected TMV in only one line with sustained high temperatures (>40 °C for 10–13 days). Infected plant material increased peak temperatures by up to 4 °C. Steaming protocols (90 °C for 20 or 40 min) showed negative outcomes: reduced plant fitness, mold growth, and inability to store treated substrate. Results were presented at the 2022 Symposium on Soil Disinfection in Almería.