TOBACCO WILDFIRE^ 



By Frederick A. Wolf, Plant Pathologist, and A. C. Foster, Assistant Plant Path- 

 ologist North Carolina Agricultural Experiment Station 



INTRODUCTION 



During the past season (191 7) a leaf disease of tobacco {Nicotiana 

 tahacum) has been the cause of much concern to tobacco growers because 

 of its destructiveness. Attention was first directed to it during June 

 when tobacco was being transplanted. Subsequently during the entire 

 growing season numerous complaints of this disease were received by 

 members of the staff of the North Carolina Agricultural Experiment 

 Station and of the State Department of Agriculture. Because of the 

 severity of the epidemic and the insistence by growers that this disease 

 was manifestly different from any they had ever seen, an investigation 

 was begun. 



A preliminary survey of the literature on diseases of tobacco revealed 

 the fact that this disease was clearly unlike any which had previously 

 been described. Furthermore, the apparently water-soaked margin of 

 the diseased areas, the tissues of which, upon microscopic examination, 

 were found to be teeming with bacteria, suggested that the disease was 

 probably of bacterial origin. Accordingly, attention in the first studies 

 was centered upon the etiology of the disorder. A brief statement (7) ^ 

 concerning this work, in which attention was directed to the presence of 

 the disease, was duly prepared. 



It was also pointed out that the causal organism was undescribed, 

 and the name "Bacterium tahacum Wolf and Foster" was suggested. 

 Promise was made in that report of a description of the morphological and 

 cultural studies upon Bact. tahacum. Besides making this description, it 

 is the present purpose to adequately describe the disease and to indicate 

 our present knowledge of its economic importance, distribution, and 

 dissemination. 



HISTORY AND DISTRIBUTION OF THE DISEASE 



While the disease was first definitely recognized in June, 191 7, near 

 Wendell, N. C, it is impossible to determine with certainty for how many 

 seasons prior to the present one the disease has existed. It is quite 

 probable, to judge from the testimony of several reliable informants, that 

 the disease caused the loss of practically the entire crop in one field, near 

 Wendell, in 191 6. Mr. E. G. Moss, Assistant Director, in Charge of the 

 Granville Branch Tobacco Station, Oxford, N. C, is convinced, as is also 



' Approved tor publication by B. W. Kilgore, Director, North Carolina Agricultural Experiment Station. 

 * Reference is made by nimiber (italic) to "Literature cited," p. 458. 



Journal of Agricultural Research, Vol. XII, No. 7 



Washington, D. C. ^ Feb. 18, 1918 



ma ' KeyNo. N.C— 9 



(449) 



