By Frank Parker, Ballstone Farm, Quarnford, Buxton, Derbyshire, UK
The problems of disease in mushroom growing houses means that a section of the workforce are continually and constantly exposed to whatever antifungal and disinfectant substances are used to keep the sheds sterile. These synthetic commercial sterilants fall into a number of categories phenols, chlorophenols, aldehydes, quaternary ammonium compounds and various types of chlorine yielding products all of which have very low toxicity levels from occasional exposure, but are much worse for continual exposure situations.
A further drawback nowadays is that sterilants are not permitted to come into contact with the crop in many countries.This necessitates that the disinfectant must be washed away well before the growing crop is put in the room. All the surfaces within this room are now clean, but have no residual protection whatsoever from subsequent re-infection from the new cropping cycle and accidental introduction of infectious pathogens onto the clean room surfaces.
Also many of these chemicals have a strong and persistent smell. Once the crop is underway no subsequent disinfection is possible in case the vapour smell is absorbed by the crop causing a potentially toxic residue in the mushrooms.
The short and long term toxicity levels for some of these synthetic chemical products is given in the table below.
SporeKill has been specifically developed for the mushroom industry to avoid these problems. First problem- the SAFETY of the clean out team
The short and long term toxicity level for SporeKill is >2575ppm.
This low toxicity has been achieved by using naturally occurring fungicidal and fungistatic substances which have been dissolved at high PH which creates a pathogen destructive solution with super low surface tension with very powerful detergency and aggressive penetration effects. These characteristics make sure that the product is absorbed into any porous (Wood or concrete) surfaces and any particles of old compost which may be remaining from the previous crop.
SporeKill also contains a strong natural film forming substance. As the product starts to dry off the concentration gets higher until a dry film is formed which incapacitates and traps all free spores and mycelium fragments. Because this film is non toxic and has no odour it should be left on the surfaces providing future protection against subsequent infection from whatever source during cropping. In fact in the UK we have approval from the Soil Association which is an Organic Accrediting organisation not to wash off after use. This film which is highly alkaline soon becomes exposed to CO2 in the growing room from the metabolism of the mushroom beds. The effect of this CO2 is to lower the PH of the SporeKill film. As this happens the antifungal effect of the product is increased by a factor of five times. So SporeKill first destroys pathogens by pH, then secondly by surface activity and film forming action and then finally as a lower PH fungicide.
The low odour and toxicity also means that floors and walls may be re-treated in cases of difficult crops during cropping.
In the situation where a quick clean down is required (not enough time for drying) e.g. outside the growing rooms on yards, machinery etc, SporeKill can be mixed with hydrogen peroxide (H202). It is very stable and provides a quick acting antifungal with a very low environmental impact. The effect on organic matter, mycelia debris and spores can be seen within seconds of applications and can be seen in the photograph below.
If you need any further information or details on rates, then please contact Nutrigain Ltd at www.nutrigain.com
