Unraveling the viral complex associated with la france disease of the cultivated mushroom, agaricus bisporus

In 1962, a landmark paper published in Nature (London) describing virus-like particles (VLPs) in diseased mushrooms, Agaricus bisporus, created a new branch of science called mycovirology (fungal virology). Besides setting a precedent for the previously unconsidered notion that a mere fungus could be infected by a virus, it established a new line of research to elucidate the etiologic agent of a devastating malady affecting the mushroom industry. This disorder, which is most commonly referred to as La France disease, was first reported in 1950 by Sinden and Hauser following a severe episode on the La France mushroom operation located in southeastern Pennsylvania. For more than a decade, the cause of La France disease baffled scientists, who had searched endlessly for the presumptive causal bacterium, fungus, or nematode, but to no avail.