THE MYCOGONE DISEASE OF MUSHROOMS AND ITS CONTROL. 15 



The investigators (Costantin and Dufour, 18926, p. 145) described 

 cultural experiments of the parasite, using sulphur dioxid produced 

 by burning sulphur. It was concluded that " sulphur dioxid has a 

 very destructive effect upon the spores of the parasite." Directions 

 are given (Costantin and Dufour, 18936, p. 411) for the fumigation of 

 mushroom caves by burning sulphur. These investigators in a later 

 publication say that the sulphur method of fumigation is attended 

 with such inconvenience that spraying with lysol is preferable (Dela- 

 croix, 1900). 



The Great Britain Board of Agriculture and Fisheries (1905) recom- 

 mends the thorough spraying of the house or other structure in which 

 the mushrooms are grown with a solution of sulphate of copper, 1 pound 

 of sulphate to 15 gallons of water, three times at intervals of 10 days. 

 This treatment has been recommended to English growers since 1905 

 (Gardeners 7 Chronicle, 1906-1912). 



Costantin and Dufour (1893a, p. 510) found that copper sulphate 

 had a very feeble antiseptic action on the parasite. In America the 

 attempts to control the disease by this fungicide have been discourag- 

 ing to the majority of the growers using it. 



Costantin (18936, p. 530) and Dufour (Costantin and Dufour, 1893a, 

 p. 504), from the results obtained in experiments in a mushroom cave, 

 advised the use of a 2.5 per cent solution of lysol. When the cave is 

 dry, one spraying is said to be sufficient, but if it is very damp two 

 thorough sprayings are to be given. A 2 per cent solution of lysol in 

 water was used to check the spread of the disease in the mushroom 

 bed in an infected cave. Places where the diseased mushrooms ap- 

 peared in the beds were watered with the solution and the disease 

 destroyed. In one of these places, watered with the disinfectant, a 

 cluster of healthy, normal mushrooms later developed. 



So-called " sanitary fluids," of which there are quite a number on 

 the market, composed of coal-tar derivatives, saponified, are of a 

 nature similar to the lysol used abroad. 



Several experiments have been made with such fluids. Although 

 the number of these experiments was limited and the results not abso- 

 lutely conclusive, in view of the previous French experiments with a 

 similar disinfectant it is thought that these sanitary fluids will be 

 effective for the uses mentioned, while the price is not prohibitive. 



PRACTICAL EXPERIMENTS TO CONTROL THE DISEASE. 



A practical application was made of the information acquired from 

 the results obtained in the laboratory experiments with formaldehyde 

 gas in the inauguration of experiments for the control of the disease. 

 This economic phase of the work received attention during several 

 years. Continuous observations were made of the same houses 

 during this period, but each succeeding year additional houses, with 



