1078 EXPERIMENT STATION RECORD. 



Among the recent observations, attention is called to the fact that in connection 

 with shriveled grains the authors found spore beds containing both uredospores and 

 teleutospores beneath the bran layer, and this seemed to indicate that possibly the 

 wheat rust could attack the plant directly from the seed. Infected seed generally 

 may be recognized by black-pointed grains, the black points being situated at the 

 germ end of the grain. A number of seeds of this character were planted in glass 

 cases, but the resultant plants did not show any rust. If later experiments should 

 confirm this possible mode of rust propagation, new light may be thrown on the 

 entire rust problem, and the importance of proper seed selection would be shown. 



Suggestions are given as to precautionary measures to be taken by farmers in order 

 that the amount of rust may be reduced as much as possible. These include the 

 thorough drainage of fields, the early and even maturity of the crop, thorough prepa- 

 ration of the soil and the use of clean seed, the selection of seed of pure varieties, 

 treatment for prevention of smut so as to insure healthy plants if possible, keeping 

 down weeds and volunteer plants which may carry the rust, destruction of all bar- 

 berry shrubs, thorough grading of seed grain, and the rotation of crops. 



Plant diseases, J. J. Thornber (Arizona Sta. Rpt. 1905, pp. 21, 22). — Brief notes 

 are given on the alfalfa leaf spot (Pseudopeziza medicaginis) and the common grain 

 rust (Puccinia grarninis) . 



Notes on Puccinia graminrs, J. Joannides (Trans, and Proc. Bot. Soc. Edinb., 

 23 (1905), pt. 1, pp. 63-67). — The author records observations on the occurrence of 

 Puccinia grarninis in Egypt and describes the continued existence of the rust during 

 several years without the usual presence in the life cycle of the teleutospore condi- 

 tion and the subsequent recidial stage on the barberry. 



Culture experiments with rust fungi, H. Klebahx (Ztschr. Pfianzenkrank., 15 

 (1905), No. 2, pp. 65-108, pi. 1, figs. 4)- — Notes are given on experiments carried on 

 by the author during 1903 and 1904 w r ith some 30 species of rust fungi. 



Among the data given are special references to the wintering of Puccinia dispersa; 

 the specialization of P. digraphidis; the alternate hosts of P. stipte; the specialization 

 of P. caricis; notes on P. polygoni amphibii, P. violse, etc. ; a new form of Uromyces 

 dactylidis; the specialization of U. scirpi; notes on Gymnosporangium clavariveforme 

 and G. juniperinum; the relationship between Ochrospora sorbi and JEcidium leuco- 

 spermum; infection experiments with Cronartium ribicola on white pine, etc. 



Helminthosporium gramineum and Pleospora trichostoma, F. Noack 

 (Ztschr. Pfianzenkrank., 15 (1905), No. 4, PP- 193-205, pi. 1). — A report is given of the 

 investigations of the author on the possible relationship between these two species 

 of fungi, and he agrees with Diedicke (E. S. R., 16, p. 64) in holding that Pleospora 

 trichostoma is the perithecial form of Helminthosporium gramineum, the cause of the 

 stripe disease of barley. 



Investigations with IT. teres and H. avenx have thus far failed to reveal their 

 perithecial stage. 



The prevention of stinking* smut of wheat and loose smut of oats, W. T. 

 Swingle ( U. S. Dept. Agr., Farmers' Bui. 250, pp. 16, figs. 7). — The author describes 

 means for the prevention of the stinking smut of wheat and loose smut of oats, the 

 methods detailed being the treatment with sar, which consists of a mixture of sul- 

 phur, alkali, and resin; the bluestone or copper sulphate and lime treatment; for- 

 malin treatment; and hot-water treatment. Directions are given for the use of these 

 fungicides and for the handling of the grain after treatment. 



The smut of wheat, C. Macias {Com Par. Agr. [Mexico], Circ. 27, pp. 4)- — A 

 brief account is given of smut of wheat, with directions for its prevention. 



Disease resistance of potatoes, W. Stuart ( Vermont Sta. Bid. 122, pp. 107-136, 

 dgms. 4). — In previous publications (E. S. R., 17, pp. 262, 670) accounts are given 

 of studies of disease resistance of potatoes. The present bulletin gives the results of 

 investigations on the resistance of vines to blight and tubers to rot. Investigations 



