DISEASES <>F PLANTS. 7<S7 



in a protoplasmic form in the tissues of the host, from which is developed mycelium 

 and spores under certain conditions of environment, is an important one and one 

 which may possibly solve some of the phenomena of the life history of other fungi. 



Three-spored rusts, M. C. Cooke (Gard. Chron., 3. ser., 36 {1904), No. 938, p. 

 418, fig. /). — In commenting upon a note given in Bureau of Plant Industry Bulletin 

 63 ( E. S. K., 16, p. 274), in which three forms of spores are described for Puccinia 

 vexans, the author calls attention to this peculiar species for the purpose of drawing 

 an analogy with others, and mentions having observed similar phenomena in Puc- 

 cinia pruni, in which this fungus produces uredospores, teleutospores, and amphi- 

 spores. 



TJredineous infection experiments in 1904, W. A. Kellerman \.Imir. Mycol., 

 11 (1905), No. 75, i>/>. 26-33). — In continuation of previously recorded experiments 

 (E. S. R., 15, p. 6S7), the author gives the resnlts of his third season's work with 

 various species of Uredinese. The principal species investigated were the maize rust 

 ( Puccinia sorghi), sunflower rust (P. helianthi), and pine rust I Peridermium pini). 



The maize rust was found capable of producing uredospores directly from teleuto- 

 spores. The uredo stage of this rust was found to he indiscriminately transferred to 

 the different biologic species of maize, seeming to indicate that there are no biologic 

 forms of this rust. In addition to maize it was found to be successfully transferred 

 to teosinte, hut inoculations on sorghum, sugar cane, and Tripsacum dactyloides 

 failed. 



Inoculation experiments with a rust taken from the artichoke showed that this 

 species is the same as the one frequenting the sunflower, /'. helianthi. Teleutospores 

 of I', thompsonii were grown on Sambucus canadensis, showing that this rust is iden- 

 tical with V. sambuci. Successful inoculations on Campanula americana were made 

 with Peridermium pini, showing that this form is contained in the life cycle of Coleo- 

 sporium campanula . 



Oat and barley smut investigations, R. A. Moore ( Wisconsin Sta. J!/>L 1904, pp. 

 317-320). — In continuation of previous investigations on oat smut ( E. S. R., 15, p. 

 1087; 16, p. 64), the author gives the results of his investigations to determine the 

 amount of smut present in oat fields throughout Wisconsin. Personal examinations 

 were made of 201 fields where the seed had not been treated for the prevention of 

 smut and in. 5 per cent of the oats was found to be diseased, while in 79 fields where 

 the seed had been treated only 0.4 per cent of smut was found. 



A tabulation is given of data collected through the Wisconsin Agricultural Experi- 

 ment Association showing that of 1,315 farmers reporting, 313 had treated their seed 

 oats for the prevention of smut, and the crop from the treated seed showed 2. 'M per 

 cent smut, while the average per cent of smut in the fields where the seed had not 

 been treated was 7.04. In a similar way 134 farmers reported on the occurrence of 

 barley smut, 14 of whom had treated their seed barley. The average percentage of 

 smut present in the fields sown with treated seed was 2.25 per cent, as compared 

 with 6.08 per cent from untreated seed. 



The author strongly urges the treatment of oats ami barley with formaldehyde for 

 the prevention of smut. He says that barley smut is on the increase in Wisconsin, 

 and from personal investigations in 176 barley fields he found that an average of 4.5 

 per cent of the crop was lost due to the disease. As the barley crop of the State 

 amounts to 13,500,000 bu., this loss, which to a great extent maybe prevented, is 

 quite serious. 



Treating seed wheat to prevent smut, E. V. Pernot (Oregon Sta. Ii/>t. 1903, 

 />/>. ■',>;, 57). — A brief account is given of the effect of treating seed wheat with differ- 

 ent strengths of solution of copper sulphate and formaldehyde and of heating the 

 dry seed for half an hour at a temperature of 150° F. The treated seed was planted, 

 and the total number of plants and the number of heads formed for each 100 seeds 

 are shown. 



22868— No. 8—05 5 



