444 EXPEEIMENT STATION RECORD. 



fungus wilt and bacterial ring diseases which attack the vascular tissues, and 

 a Rhizoctonia and a blackleg which are classed as foot diseases. 



An account is included of the system of inspection adopted in Germany to 

 secure certification of seed potatoes. 



A preliminary study of ergot of wild rice, Faith Fyles (Phytopathology, 

 5 {1915). No. 3, pp. 186-102, pi. 1). — In connection with studies of the Canadian 

 wild rice {Zizania aqiiatica and Z. palustris) the author reports often hav- 

 ing noticed ergot among the seed, and the questions arose whether this ergot 

 was identical with the typical ergot of rye, and whether other cereals and 

 other grasses growing in the neighborhood would be in danger of infection 

 by it. Material was collected and a series of experiments carried on in which 

 only negative results were obtained for species other than wild rice. 



The author believes, from certain morphological and other differences, that 

 the form experimented with is a distinct species, and it will be a subject for 

 further report 



The loose kernel smut of sorghum, A. A. Potteb (Phytopathology, 5 (1915), 

 No. 3, pp. lJt9-15Jf, pi. 1, figs. 2). — In a previous publication (E. S. R.. 27, p. 

 545) the author reported the occurrence of Sphacelotheca ciuenta on sorghum 

 in this country, and in the present paper au attempt is made to clear up 

 confusion between this species and K. sorghi. Both species are present as 

 kernel smuts of sorghum, /S. cnicnta being now kuoN\Ti to have occurred in 

 America as early as 1.SN5. 



It is claimed that infection may be prevented by the usual seed-disiufectiug 

 treatments. 



A bibliography is given. 



Experiments on the susceptibility of sweet potato varieties to stem rot, 

 L. L. Habtek and Ethel C. Field (Phytopathology, 5 (1915), No. 3, pp. 163- 

 jQS).—ln a previous publication (E. S. R., 32, p. 50) the authors gave an account 

 of investigations, which had extended over two years, on stem rot of sweet 

 potatoes due to Fusariuin hypcroxy.'ipuntm and /•'. baiatatis. 



In the present paper an account is given of the results of variety tests, 

 carried, on in the seasons of 1013 and l'.»14, which showed marked resistance 

 on the part of some varieties, but the authors claim that a substitution of one 

 variety of sweet potatoes for another can not be made based solely on the 

 resistance to these diseases. Some varieties which produce potatoes of excei>- 

 tional merit in certain localities are said to be practically worthless in other.s. 



How to disinfect tobacco plant beds from root rot fungus (Thielavia), 

 A. D. Selby, T. Hovsek, and J. G. Humbert (Ohio Sta. Circ. 156 (1915), pp. 5-8, 

 fig. i).— Soil sterilization of seed beds by means of steaming and the use of 

 formalin is described, the advantages and disadvantages of each method being 

 pointed out. 



Apple rust and its control in Wisconsin, L. R. Jones and E. T. Babtholo- 

 mew (Wiftconsin Sta. liul. 257 (1915), pp. 1-30, figs. 15).— \ description is given 

 of the apple rust due to Gyiinwsporaiujium glohosum and O. juiiipcri-virgiuiana\ 

 The latter species is said to be the more widely spread and injurious in 

 Wisconsin. 



Attention is called to the relation between the fungus occurring on the 

 cedar and the applo, and, as orchard planting is said to be on the increase 

 in the regions where red cedars abound, suggestions are given for the avoid- 

 ance of loss through the control of the disease by spraying, cutting out the 

 cedar trees, and use of relatively resistant varieties of apples. 



Varietal resistance of plums to brown rot. W. D. Valleau ( V. S Dcpt. Agr., 

 Jour. Agr. Research, 5 (1915), No. 9, pp. 365-396. pis. 3).— The results arc 

 given of studies made at the Minnesota Experiment Station on the resistance of 



