No. 2, June, 1921] PATHOLOGY 205 



the first appearance of mildew in Ireland and its subsequent spread into Sweden and other 

 European countries. Digging and burning were the first methods of control advocated. 

 Henning in 1907 reported good results from pruning and spraying. Results with other con- 

 trol methods are discussed. The production of good resistant varieties by means of crosses 

 between European and American varieties is considered possible. The results of spraying 

 experiments with 17 different spray materials are given. The mildew is said to be most 

 severe on bushes grown in moist locations or fertilized with nitrogenous materials. A brief 

 discussion of the quarantine laws in several European countries is given. Control methods 

 advocated include the cutting out and burning of diseased portions in the fall, together with 

 liming and cultivating the bushes. The eradication of nearby wild bushes is advised. In 

 the spring, the tops of plants to be set out should be dipped in 1-40 formalin solution, and 

 plants should be sprayed with a formalin solution. If buds have not started, a 1-40 or 1-60 

 solution is recommended; but if plants have begun to bud, a 1-100 solution should be used. — 

 Mr. and Mrs. W. W. Gilbert. 



1421. HoLBERT, J. R., J. F. Frost, and G. N. Hoffer. Wheat scabs as afifected by 

 systems of rotation. Phytopath. 9 : 45-47. 1919.— A report of a survey of 1500 acres of wheat 

 in 28 fields in central Illinois. Wheat following corn showed considerably more scab (Gib- 

 berella saubinetii (?) than when following wheat, oats, or clover in the rotation. In 1 field, 

 wheat following 2 years of corn yielded 25 bushels with 20 per cent scab; wheat following 1 

 year of com yielded 33 bushels with 2 per cent scab. The most severe scab infestations were 

 foimd in low places where trash from the preceding crop had collected. — C. W. Bennett. 



1422. Murphy, Paul A., and E. J. Worthy. Relation of climate to the development and 

 control of leaf roll of potato, Phytopath. 10: 407-414. 1 fig. 1920.— Hill selections of leaf- 

 roll plants from Prince Edward Island in 1916 were planted in 1917 in tuber units at Charlotte- 

 town, Prince Edward Island; Bermuda; and Ottawa, Canada. Plants from the same hills 

 reacted similarly at each station. The next year the Bermuda seed at Charlestown showed 

 97.5 per cent leaf-roll compared with 60.7 per cent in local stock. Authors suggest wholesale 

 introduction of potato seed from disease-free districts as a practical means of control. — 

 R, E. Vaughan. 



1423. Peyronel, B. Sevrnamento di Marsonia juglandis sui rami e polloni del note. 

 [The overwintering of Marsonia juglandis on the branches and shoots of the walnut. Staz. 

 Sperim. Agrarie Ital. 53: 168-171. 1920.— The author found in the winter months, on the 

 young branches and twigs of Juglans, the conidial form of Marsonia juglandis, and suggests 

 a close examination of the branches of infected plants, since these are exceedingly good 

 sources of infection in early spring. — A. Bonazzi. 



\^2A. Stevenson, John A. Control of sugar cane mottling disease. Sugar 22: 539-541. 

 Fig. 1. 1920.— An article reprinted from Jour. Dept. Argic. Porto Rico. Methods being 

 used in Porto Rico to control the mosaic disease of sugar cane are discussed. — C. W. Edgerton. 



1425. TicE, C. Seed-potato inspection. Agric. Jour. [British Columbia] 5:276. 1920. 



1426. TicE, C. Potato certification in B. C. British Columbia Dept. Agric. Circ. Bull. 

 32. 6 p. 1921. 



1427. Walker, J. C. Experiments upon formaldehyde-drip control of onion smut. Phy- 

 topath. 10:323-327. 1920.— Experiments conducted near Racine, Wisconsin, from 1913 to 

 1918 show that the application of approximately 200 gallons of 1 : 128 formaldehyde solution 

 per acre gives satisfactory control of onion smut. When the quantity of solution is reduced 

 to 120-150 gallons the writer advises increasing the concentration to 1:64. — R. E. Vaughan. 



