A challenge to mushroom growers: the green mould disease of cultivated champignons

The aim of this minireview is to give an overview of the literature about the green mould disease of cultivated champignons (Agaricus bisporus) caused by Trichoderma species. The first significant green mould epidemic appeared in Northern Ireland in 1985, which was quickly followed by subsequent outbreaks in several countries. The symptoms of green mould appear as large patches of compost turning green rapidly. Epidemic outbreaks are due to two varieties of the species T. aggressivum. This species competes efficiently for space and nutrients, produces extracellular enzymes, toxic secondary metabolites and volatile organic compounds, which results in drastical crop losses. The natural habitat of T. aggressivum is still unknown. Possible routes of infection include the air, vehicles, contaminated clothes and animal vectors. A primer pair for the specific identification of T. aggressivum is available for the fast and cheap monitoring of the causal agent. Possible management strategies include the application of disinfectants, pasteurization, adjustment of casing pH, chemical treatments, biological control by antagonistic bacteria as well as the cultivation of resistant Agaricus varieties.