BULLETIN 292 

 POTATO MOSAIC. 1 



Donald Folsom. 

 SUMMARY 



(1) Potato mosaic has been known in Europe for many- 

 years and in Maine since 1912. At present it is well established 

 in this state. It is also well distributed over the United States. 



(2) The mosaic of tobacco, a plant related to the potato, 

 has been thoroughly studied and apparently is quite similar to 

 potato mosaic. However, there are important differences be- 

 tween the two maladies. 



(3) Potato mosaic has certain marked effects upon the ap- 

 pearance, physiology, and yield of potatoes. 



(4) It is transmitted by the tubers of infected plants^ 

 whether or not these plants have had time to show the usual 



2 This bulletin is largely based upon investigations conducted as a 

 cooperative project between the Office of Cotton, Truck and Forage Crop 

 Disease Investigations of the Bureau of Plant Industry, U. S. Depart- 

 ment of Agriculture, and the Department of Plant Pathology of the 

 Maine Agricultural Experiment Station. Such results of this cooperative 

 investigation as are included herewith have already been published in 

 different form as follows : Schultz, E. S., Folsom, D., Hildebrandt, F. M., 

 and Hawkins, L. A. Investigations on the mosaic disease of the Irish 

 potato. Jour. Agr. Research 17:247-274. PL A-B (col.), 25-30. 1919. 

 Schultz, E. S. and Folsom, D. Transmission of the mosaic of Irish 

 potatoes. Jour. Agr. Research 19:315-337. PL 49-56. 1920. The articles 

 just mentioned are not, however, available to the general reader, except 

 in libraries. Moreover they are written more from the standpoint of 

 the investigator. It is believed that the information contained in them 

 and certain other general information relative to the nature and impor- 

 tance of potato mosaic should be given to the potato growers of Maine 

 as a Station bulletin. Dr. Folsom's name as author of the present pub- 

 lication implies no assumption of credit for work done other than that 

 he has been the Station representative actively engaged in the prosecu- 

 tion of the cooperative investigations on potato mosaic and thus is the- 

 logical person to put the results obtained into form for a Station bul- 

 letin. Chas. D. Woods, Director. 



