J0161 DISEASES OF PLANTS. 845 



remained entirely Immune, while another gave 75 per cent Infection. Most of 

 the varieties tested belonged to the si>eoies Triticitm durum and T. vulgnrc 



The oat mildew was tested on 6 sinx-ies and varictk's of Avona, and wltli one 

 exception (.4. barbatn), these tests pive 100 ix-r cent infection. Additional tests 

 were made with both the wheat and the oat mildew on varieties studli'd, with 

 results that confirm previous work (E. S. U.. Xi. p. 244). 



Bacterial blights of barley and certain other cereals, L. K. Jones, A. G. 

 Johnson, and C. S. Reddy {Science, n. ser., J,^ (1916), No. 113^, pp. 4.'{2, 438 ; 

 abs. in Phytopathology, 6 (1916), No. 1, p. 98).— A brief account Is given of a 

 bacterial di.sease of barley which Is characterized by water-soaked lesions with 

 a bacterial exudate on the leaf sheaths and glunie.s. Laboratory and field studies 

 have been made of the organism, which appears to be a species of I'scudomonas. 



Similar diseases have been found and studle<l on wheat, spelt, and rye, and 

 from each of these hosts the causal organism has been Isolated and Its patho- 

 genicity fully determined. The organisms from the.se three sources are believed 

 to be all one species which is quite similar to the barley blight organism. 



A detailed account of the study of barley blight, together with a technical 

 description of the organism, is expected to appear soon. 



B>egarding the changes in the chemical composition of rye resulting from 

 the activity of certain Fusarium forms, A. PomaskiI (Hat. Mikol. i Fitopittol. 

 Ross., 1 (1915), No. 4, pp. 77-106). — Analytical and biological study of the dis- 

 ease of grain known in Russip as " drunk bread " is said to have shown that 

 in the cases under investigation F. roseum and F. subulatum were present. It Is 

 thought that other species may be concerned in this trouble. 



F. roseum and F. subulatum appear to act similarly on grains, di.ssolving 

 starch and decomposing albumins. Loss of these substances, and in a less degree 

 of others, totaled in cultures one month old 25.1 per cent. Great changes were 

 also noted in the pentosan, fiber, and fat. There was a decrease of the iodln 

 number and an increase of the acid number. Among the products of the decom- 

 position of the albumins was a toxin, probably a nitrogenous glucosld. Further 

 study is to be made of this toxin and of other products of the action of certain 

 Fusarium forms. 



Observations on the pathological morphology of stinking smut of wheat, 

 M. F. Babsus (Phytopathology, 6 (1916), No. 1, pp. 21-28, figs. 3).— An oppor- 

 tunity having been presented to watch the development of plants in experimental 

 plats in reference to control of the stinking smut of wheat, caused by Tilletia 

 fwtens, the author made a careful study of the plants from the time they were 

 in bloom until harvest. The symptoms of the various parts of the host as In- 

 fluenced by the parasite are described at length. 



Grain smut investigation and control, G. M. Reed, Emma B. Mundy, and 

 N. M. GiBBs (Missouri Sta. Bui. 141 (1916), p. 26). — Continuing previous work 

 (E. S. R., 33, p. 245), experiments were conducte<l to determine the rate of 

 infection of bunt in wheat, the susceptibility of the various species of oats to 

 loose smut, the relation of early and later planting of oats to the amount of 

 smut, and the effect of temperature, soil conditions, depth of planting, and 

 germination of seed on the amount of smut. 



Avena strigosa proved to be the only variety of oats immune In all the experi- 

 ments, while A. sterilis gave the highest percentage of infection. Most of the 

 species of common oats proved susceptible to the loose smut. Late planting, 

 contrary to the belief among plant pathologists, generally resulted in a higher 

 percentage of infection than early planting. 



Fiingicidal treatment of seed grains, L. Malpeaux (Jour. Ayr. Prat., n. ser., 

 29 (1916), No. 5, pp. 98, .99).— Reporting results of tests made In 1914, the 

 author states that copper sulphate solutions of 0.5 per cent or more as use<l 



