446 EXPEKIMENT STATION RECORD. 



Cotton anthracnose, H. W. Bakre {South Carolina Sta. Circ. 1, pp. 3). — 

 This circular gives a survey of the situation in South Carolina in relation to 

 the cotton anthracnose, describes the symptoms of the disease and methods for 

 combating it, and requests information from planters in relation to various 

 factors of distribution and control. 



Cotton anthracnose, H. W. Baeke (South Carolina Sta. Bui. 164, PP- ^2, pi. 1, 

 figs. 6). — The author has for a number of years been conducting investigations 

 on cotton anthracnose, the technical results of which have been published in 

 the reports of the station (E. S. R., 26, p. 647). The present bulletin brings 

 together in a nontechnical form the information gained to date. The author 

 shows that the disease is spread principally by infected seed and that the 

 fungus retains its vitality in diseased seed for probably 2 years or more. In 

 the field the fungus does not remain alive for more than 1 year. It is claimed 

 that crop rotation and seed selection will control this disease, which is widely 

 spread and very destructive. 



Investigations on potato diseases (third report), G. H. Pethybridge {Dept. 

 Agr. and Tech. Instr. Ireland Jour., 12 (1912), No. 2, pp. 33^-359, pis. 3)j— 

 This report gives an account of further studies on various diseases of the 

 potato and means for their control (E. S. R., 25, p. 454). Among the diseases 

 investigated were the ordinary potato blight, sclerotium disease, black stalk 

 rot, corky or powdery scab, leaf cui'l, leaf roll, sprain, and a new form of 

 potato rot. 



In spraying experiments for the potato blight, due to Phytophthora infestans. 

 Burgundy mixture, Bordeaux mixture, and lime-sulphur solution were com- 

 pared. On account of the difficulty of obtaining good lime the Burgundy 

 mixture is given preference over Boi'deaux mixture. The lime-sulphur solution 

 was found practically useless in warding off potato blight. 



For the sclerotium disease, due to Sclerotinia sclerotiorum, no efficient method 

 of treatment has been found, though spraj hig and cultural methods were tested. 



The effect of heating tubers infected with the organism of the black stalk 

 disease (Bacillus melanogenes) for 4 hours at 50° C. was tested but without 

 any striking results. When the tubers were subjected to lower temperatures 

 the rot seemed to be accentuated. 



The author definitely establishes the fact that Spongospora subterranea, the 

 cause of the corky or powdery scab, produces galls on the roots of the potato 

 plant. Soil fungicides were found to reduce the injury due to this organism. 



Attention is called to the differences between leaf curl and leaf roll of the 

 potato. 



A new tuber rot was investigated which the author states can not be classed 

 as a wet or a dry rot, as it does not exhibit the characteristics of either. The 

 disease occurs in a number of regions in Ireland. It attacks the lai'ger tubers 

 and may cause serious losses in the crop. A study of material demonstrated 

 that it was not due to bacteria, while a fungus was isolated from some of the 

 diseased tubers which is believed to be the cause of the rot. The fungus 

 resembles P. omnivora. This form of tuber rot is to be investigated further. 



The Alternaria blight of ginseng, H. H. Whetzel (Spec. Crops, n. ser., 11 

 (1912), No. 117, pp. 91-95). — The Alternaria blight, due to A. panax, is said 

 to be the most common, widespread, and best known disease of ginseng. It is 

 reported as occurring quite widely throughout the United States, practically 

 in every region where the plant is grown. The symptoms of the disease and the 

 life history of the parasite are described at some length and suggestions given 

 for its control. 



According to the author, great care should be exercised to exclude the fungus 

 from the ginseng gaxdeu, as its eradication after once becoming established is 



