DISEASES OF PLANTS. 243 



" Grey leaf " or " dry leaf " on oats (Edinb. and East of Scot. Col. Agr. Rpt. 

 SO {1013), pp. 22, 2S; abs. in Jour. Bd. Agr. [London'\, 20 {191 Jt), No. 11, p. 

 1010). — This disease, noted recently as attacking certain varieties of oats 

 named, is said to cause early decoloration, without yellowing, however, of the 

 leaves along the margins and near the bases, these effects spreading upward 

 with the growth of the plant. The upper leaves may show a healthy color or 

 else red stripes. Heads are absent, or late and small, grains being few or 

 poorly developed. Some varieties, as Polish White, show only slight attack. 

 While the disease is regarded as due to some condition not yet fully understood, 

 it is thought to be favored by fertilizers which produce an alkaline soil, as 

 sodium nitrate and basic slag, and to be lessened by such fertilizers as ammo- 

 nium sulphate and superphosphate. Manganese sulphate is also credited with a 

 beneficial influence. 



Leaf cut, or tomosis, a disorder of cotton seedlings {Agr. News [Barbados}, 

 13 {1914), No. 312, pp. 126, 127). — ^The occurrence in St. Croix is reported of 

 a serious infection of cotton closely resembling that which has been previously 

 described by Cook as occurring in the United States (E, S. R., 29, p. 47). 



Tikka disease and the introduction of exotic groundnuts in the Bombay 

 Presidency, E. J. Butler {Agr. Jour. India, 9 {191^), No. 1, pp. 59-70, figs. 4)- — 

 Reviewing briefly circumstances connected with the decline in yield of the 

 peanut ascribed to Septogloeum arachidis in the period from 1895 to 1902 

 in parts of India and the progress toward recovery since 1903, the author dis- 

 cusses the apparent influence of the introduction of foreign and the possible 

 development of resistant native varieties, suggesting, however, that probably 

 not all the factors involved have as yet received full recognition. 



Potato scab and potato canker, G. Kock {Ztschr. Landw. Versuchsw. Osterr., 

 16 {1913), No. 10, pp. 1005-1008, figs. 2).— Noting from specimens sent to the 

 station as supposed cases of potato canker, the existence of an apparent con- 

 fusion of this disease due to Chrysnphlyctis cndobiotica with scab ascribed to 

 Oospora scabies, Spongospora solani, etc., the author gives illustrated descrip- 

 tions of each disease in typical form. 



Powdery scab of potatoes, W. J. Mokse {Maine Sta. Bui. 227 {1914), PP- 89- 

 104, pl^i. 4). — An account is given of the history and distribution of the powdery 

 scab of potatoes due to Spongospora subtcrrunea, the ocurrence of which in 

 the United States has been previously noted (E. S. R., 29, p. 448). While the 

 fungus has not been present in this country long enough to secure exact data 

 regarding its behavior, the author describes its principal characteristics, and 

 some diseases for which it may be mistaken, discusses its economic importance, 

 and gives suggestions relative to means to be employed for the prevention of 

 its spread, the information being largely drawn from the work of Pethybridge 

 (E. S. R., 29, pp. 44S, 549) and Giissow (E. S. R., 29, p. 448). 



[Orders regarding plant diseases] {Jour. Bd. Agr. [London], 20 {1914), 

 No. 11, pp. 1020-1024). — This article covers substantially the same ground as 

 that previously noted on wart disease of potatoes (E. S. R., 31, p. 149). 



Yellowing of sugar beets, A. Malaqxjin and A. MoiTifi {Engrais, 29 {1914), 

 No. 9, pp. 24I-243). — Giving a brief discussion of the history, characters, and 

 effects of beet yellowing, the authors state that the disease may be spread by 

 the mother beets, by seed, and by debris left in the soil. To recommendations 

 as given by Delacroix (E. S. R., 16, p. 479) in connection with his description 

 of the alleged cause. Bacillus tabificans, are added their own suggestions, 

 namely, drying the seed at from 40 to 55° C. to a water content of from 5 to 7 

 per cent, also rigorous selection of roots '■o be used for production of seed. 



