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THE INFESTATION OF FUNGUS CULTURES 

 BY MITESi 



(ITS NATURE AND CONTROL TOGETHER WITH SOME 

 REMARKS ON THE TOXIC PROPERTIES OF PYRIDINE) 



By sibyl T. JEWSON, M.Sc. 

 {Department of Mycology, Rothamsted Experimental Station, Harpenden), 



AND F. TATTERSFIELD, B.Sc, F.I.C. 

 (Rothamsted Experimental Station). 



(With 4 Text-figures.) 



CONTENTS. 



1. Introduction .... 



2. Nature of Infestation . 



3. The Problem of Control 



4. Experimental .... 



5. Quality of Pyridine 



6. Toxicity of Pyridine to the eggs of Mites 



7. Action of Pyridine on Mites (Quantitative) 



8. Toxic action of Pyridine on Fungi 



9. Discussion of Results .... 



10. Application of Method 



11. Summary and Conclusions . 



PAGE 



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1. Introduction. 



The infestation of pure cultures of fungi by mites is a considerable 

 source of trouble in mycological laboratories. This difficulty having arisen 

 at Rothamsted, it was considered advisable to make a careful study of 

 the nature of the infestation and the toxic effect of a number of volatile 

 organic chemical compounds on these pests and on fungi. The object of 

 the investigation was to find a method of controlling the mite infection 

 without injuring the fungi. Once having gained access to the laboratory 



^ A grant in aid of publication has been received for this communication. 



