250 EXPERIMENT STATION RECORD. [Vol.36 



No soil treatment was found beneficial in eradicating the disease, though sulphur 

 at the rate of 900 lbs. per acre reduced the amount of the disease. 



Several types of dry rot were found to follow attacks of S. subterranea. 

 Among these, a dry rot due to a species of Phoma is described under the name 

 P. tuberosa n. sp. 



The potato powdery scab quarantine, R. K. Beattie {Abs. in Phytopathology, 

 6 {1916), No. 1, pp. 95, 96). — An account is given of the quarantine established 

 in 1914 because of the potato powdery scab, and it is stated that a careful sur- 

 vey of the potato-growing States which use Maine seed showed that the disease 

 has established itself in only one place, this being in northeastern Florida, 

 whore a slight infection is reported. Experiments by the Bureau of Plant 

 Industry, of the U. S. Department of Agriculture, confirm the probability that 

 this disease would not become serious outside of the northern, cooler regions. 

 Consequently, it was considered unnecessary to continue the quarantine, which 

 was removed September 1, 1915. 



The black leg' disease of potatoes caused by Bacillus solanisaprus, P. A. 

 Murphy {Canada Expt. Farms Bat. Circ. 11 {1916), pp. 8, figs. 6). — A brief de- 

 scription of the symptoms and injuries due to black leg of potato, also of the life 

 history and control of the causal organism, B. solanisaprus, is given. The au- 

 thor suggests the careful selection of seed tubers and steeping those which are 

 to be so used for three hours in corrosive sublimate (2 oz. to 25 gal. water) or 

 for two hours in foi'malin (1 pint to 30 gal. water), with careful disinfection 

 of knives used in cutting seed tubers and the use of well-drained soil for 

 planting. 



Late blig"ht and rot of potatoes caused by the fungus Phytophthora in- 

 festans, P. A. Murphy {Canada Expt. Farms Bot. Circ.^0 {1916), pp. 13, figs. 

 2). — Discussing briefly the symptoms, life history, and control of P. infestans, 

 the cause of late blight of potato, this circular gives directions for preparing 

 and mixing the components of Bordeaux mixture, timely use of which has been 

 found to be effective and profitable in this connection. 



Studies in the control of storage rots of the sweet potato, J. J. Taubenhaus 

 {Abs. in Phytopathology, 6 {1916), No. 1, p. 106). — In connection with investi- 

 gations of sweet-potato diseases and their control (E. S. R., 34, p. 156), atten- 

 tion is called to the necessity for proper ventilation, fumigation, and the use of 

 fungicides for the control of these diseases. 



Two interesting diseases on greenhouse tomatoes, M. T. Cook and C. A. 

 ScHWARZE {Abs. in Phytopathology, 6 {1916), No. 1, p. 104). — A leaf spot which 

 is due to a fungus resembling Ascochyta lycopcrsici and a fruit rot due to 

 Botrytis sp. are described as occurring on greenhouse tomatoes. 



Observations on fire blight in the Yakima Valley, Washington, J. W. 

 HoTSON {Phytopathology, 6 {1916), No. 3, pp. 288-292, pis. 2; abs. in No. 1, pp. 

 115, 116). — The author reports that in the summer of 1915 a number of un- 

 usual conditions were observed in the study of fire blight. The organism is 

 now known to occur on cherries, to gain entrance to pear trees through leaves, 

 to produce a red streak in the sapwood of some varieties of pears, to infect 

 the Yakimine (a cross between a prune and a peach), and to produce an ab- 

 normal amount of fruit infection. The fruit infection in some cases was traced 

 to injuries produced in thinning apples. 



Black rot, leaf spot, and canker of pomaceous fruits, L. R. Hesler {New 

 York Cornell Sta. Bid. 379 {1916), pp. 51-1^8, pis. 8, figs. 20).— The results are 

 given of an extensive study of the black rot, leaf spot, and canker of pomaceous 

 fruits. A study was made of the host plants, varietal susceptibility, history 

 of the disease, etc., and notes are given on its geographic distribution and 

 economic importance. The symptoms of disease on the different parts of the 



