1916] DISEASES OF PLANTS. 351 



In a few instances, there was some indication that concentrations lower than 

 those causing injury might reduce the development of the leaf parasites to 

 some extent. This was true of iMJtassium nitrate, sodium acetate, morphine 

 sulphate, calcium nitrate, copper sulphate, lime water, sodium tungstate, and 

 potassium permanganate. In some cases there was less leaf disease developed, 

 particularly in case of S. lycopcrsici, on the higher concentrations where these 

 were not strong enough to cause injury, but in general the results were negative. 



Some orchard diseases and their treatment, C. R. Obton {Proc. State Hort. 

 Assoc. Penn., 55 {19 H), pp. 4-^-56, pis. 6). — Tlie author discusses some of the 

 more destructive orchard diseases prevalent in Pennsylvania, the number of 

 which has greatly increased during recent years, naming their several orchard 

 and wild hosts, describing their symptoms, and pointing out various control 

 measures. Those taken up are fire blight {BaciUus amylovarus), bitter rot 

 (Glomerella rufomaculans), black rot (Sphceropsi^ malorum), apple rust 

 {Crymnosporangium junipert-iHrginianas) , orange rust of quince (G. germinale) , 

 and brown rot of peach, plum, and cherry (Sclerotinia cinerea), with mention 

 of others of less importance. 



Experiments with rust and Coryneum of fruit trees, A. Cadoret and A. 

 Desmoumns {Prog. Agr. et Vit. {Ed. VEst-Centrc), 36 {1915), No. ^6, pp. 468- 

 471). — Discussing the characters, importance, and extension of those two dis- 

 ea.ses, also tests with remedial measures made or reported, the authors conclude 

 that the higher concentrations of the sprays sometimes used are unnecessary, 2 

 per cent being considere<l as suflicient for Bordeaux mixture or neutral copper 

 acetate. The materials added to the sprays to increase their capacity for 

 spreading and adhesiveness do not appear to have been very successful except 

 in case of gelatin added to copper acetate. Lime sulphur sprays are said to 

 have been very inferior in their results to the preparations based on copper. 



The development of perithecia in Venturia ineequalis, K. Kiluan {Bcr. 

 Deut. Bot. Gc^elL, 33 {1915), No. 4, pp. 164-168, figs. 2).— The author gives an 

 account of his observations, so far as completed, on the developmental history, 

 in relation to apple leaves, of Fusicladium dendriticum (the conidial stage of V. 

 inwquaUs) associated with apple and pear scab. 



Influences affecting cherry culture, Sprenger {CuUiira, 27 {1915), No. 325, 

 pp. 291-295). — Among the conditions mentioned as influencing returns from 

 cherry culture in southerly portions of the Netherlands are various biological, 

 physiological, and weather conditions, and pathological fungi, including Monilia, 

 Coryneum, Valsa Icucostoma, and Armillaria mcllca. 



Common diseases of the grape, M. T. Cook {New Jersey Stas. Circ. 55 

 {1916), pp. 3-8, figs. 2). — Descriptions are given of some of the more common 

 diseases of the grape and suggestions offered for their control. 



A brief report Is also presented of grape-spraying experiments in 1915, in 

 which an early spraying was given certain plats, and the results contrasted 

 with those from plats sprayed as in the general practice in that vicinity. The 

 plats receiving the extra spraying were given six applications, the first early in 

 May, while the others received five applications, beginning June 17. At har- 

 vest, rows were selected for measurement from the dilTerent plats, and those 

 which had received the extra spraying in May yielded an average of 6G.5 

 baskets, or 25 baskets per four rows more than those treated in the ordinary 

 manner. 



A vine disease due to a Hypochnus, A. Lendnkr {Bui. Sor. Bot. QenCvc, 2. 

 ser., 6 {1914), No. 4, pp. 104-106, fig. 1). — A fungus doscribod as H. burnati 

 n. sp. is considered as secondarily parasitic or saprophytic on grapevines. It 

 may be related to the lime content in the soil. 



