Therefore, it is important that compost undergoes sufficient pasteurisation treatment and that strict hygiene methods are followed.
The aim of HDC project M 057 was to identify the pasteurisation conditions needed to eradicate moderate inoculum levels of Trichoderma aggressivum from compost and to identify the most effective disinfectants in killing Trichoderma spores and mycelium.
The project found that compost should be pasteurised at 60 degsC for 12 hours in a Trichoderma outbreak and that shorter periods should only be used if Trichoderma is not a problem. Boosting ammonia levels during pasteurisation did not improve Trichoderma kill or reduce the temperature or time requirement of the treatment.
Phenolic disinfectants were found to be the most suppressive to Trichoderma mycelium growth but should not be used where they can come into contact with the crop because they are detectable at very low levels. Omnicide M was the most effective non-phenolic disinfectant in killing spores and Sporekill was most suppressive to mycelial growth. They can be used for disinfecting trays and shelves, which should then be washed down.
The EU-funded project "MushTV" follows this work and is identifying alternative disinfectant products for large pieces of machinery as well as investigating Trichoderma aggressivum and Mushroom Virus X.
Horticultural Development Company
For details on all HDC activity, visit www.hdc.org.uk