DISEASES OF PLANTS. 245 



In the light of the above facts the author coucludes that for the present and 

 until evidence is found to the contrary, Neocosmospora should be regarded as 

 simply an accidental saprophyte, having no relation to the wilt of cowpeas or 

 to the internal fungus (F. vasinfcctum) , which Is probably the true cause of 

 the wilt. 



A new disease (Sclerotinia) of the mang'old, E. S. Salmon (Jour. Southeast. 

 Agr. Col. ^Vye, 1909, No. 18, ;>/>. 328-333, pis. 2). — Attention is called to a storage 

 rot of mangolds which in its earlier stages produces dark brown or blackish dis- 

 colorations of portions of the interior of the root. Later, definite areas on the 

 surface of the root soften, turn brown, and finally culminate in a rapid rot which 

 destroys the entire root. 



An examination of the discolored interior parts of the roots showed the pres- 

 ence of a fungus mycelium which penetrated the cells and occupied the inter- 

 cellular spaces. These hyphie secrete two ferments, one which softens and dis- 

 solves the cell walls, while the other attacks and kills the protoplasm of the 

 cells, turning it a brown color. By means of cultures the fungus is demonstrated 

 to be a parasite belonging to the Botrytis genus. The disease was produced on 

 both swedes and mangolds by inoculation with Botrytis conidia obtained from 

 attacked mangolds. 



As a remedy for this rot the author advises gowl ventilation and drainage of 

 the storage pit, the rejection of all cut and bruised roots, and the avoidance of 

 turnip, swede, mangold, or potato tops as a covering for the pit. 



Field experiments on the control of the potato scab, A. Beenhaed (Deut. 

 Landw. Presse, 38 {1911), Nos. 15, pp. 168, 169, figs. 3; 16, pp. 179, ISO, fig. 1).— 

 The author reports the results of further experiments (E. S. R., 23, p. 744) with 

 sulphur in combating the potato scab. Marked beneficial results were obtained 

 by using the sulphur in controlling the scab, in greater resistance to leaf-roll 

 disease, and in obtaining yields of potatoes less subject to rot. 



Wart disease or black scab of potatoes, E. S. S.vlmon {Jour. Southeast. 

 Agr. Col. Wye, 1909. Xo. IS. pp. 29-^-318, pis. 5).— The author discusses the life 

 history of the organism, characters of the disease, its continued dissemination, 

 present distribution in England, Wales, Scotland, and Ireland, and the prohibi- 

 tion of exportation of potatoes on account of the prevalence of wart disease in 

 Great Britain. It is claimed that under the existing laws and conditions farm 

 lands generally are in great danger of becoming infected, that land once infected 

 remains so for eight years, and that the use of sulphur, lime, and soot have 

 proved absolutely valueless in combating the disease. 



Wart disease of potatoes, and horse-radish disease in Cheshire, T. H. Mid- 

 DLETON {Bd. Agr. and Fisheries [London], Intel. Div., Ann. Rpt. Proc. 1909-10, 

 pp. 36-61, 66, 67). — In a report on the Destructive Insects and Pests Order of 

 1910 the status of these diseases in England is given, including the present dis- 

 tribution of the wart disease of the potato, susceptible and resistant varieties, 

 the results of experiments in soil disinfection with sulphur, lime, lime and sul- 

 phur, soot, and soot and sulphur, the results of variety tests at many centers of 

 the disease as to the immunity or susceptibility of some 18 varieties of potatoes, 

 and a brief note on the horse-radish disease in Cheshire. 



In soil disinfection for controlling the wart disease of the potato, the treat- 

 ment in every case was a complete failure. In the variety test the Langworthy 

 type was found to be immune to the disease, while many other varieties under 

 the same conditions of soil infection were badly diseased. It is stated that the 

 disease is dangerous and very difficult to eradicate, and that cleanliness and the 

 destruction of infected tubers, stems, and all other potato debris is a most 

 important factor in combating the disease. 



