50 EXPERIMENT STATION RECOED. 



Ji't-J)6). — Brief accounts are given of diseases observed during the year. Among 

 them are grape mildew, peach mildew, rasjiberry yellows, asparagus rust, bac- 

 terial blight to tomatoes, strawberry leaf blight, and Rhizoctonia of sugar beets. 



Report of the horticulturist, F. M. Rolfs (Florida SKi. Rpt. 1905, pp. 

 29-47). — A report is given of observations made relating to the diseases of a 

 large number of plants of economic importance, the diseases being listed under 

 the different host plants. Directions are given for the preparation and use of a 

 number of standard fungicides. 



Fungi as related to weather, B. D. Halsted. E. J. Owen, and J. K. Shaw 

 (Netc Jer.scu Ktas. Rpt. lUil.'). pp. .510-.517). — A tabular account is given showing 

 the rainfall, temperature, and sunshine, and also statement-^ regarding the occur- 

 rence of plant diseases during the months from April to September. The rainfall 

 was somewhat below the average during the early part of the sunnner, but it 

 exceeded the normal in August and September. Comparing the rainfall, dryness, 

 temperature, etc., with the reported occurrence of diseases there seems to be 

 shown a close relationship between the occurrence of diseases and the meteoro- 

 logical conditions. The occurrence of fungi on various economic plants in the 

 station grounds is briefly noted. 



Channels of entrance and types of movement in bacterial diseases of 

 plants, E. F. Smith (Abs. in Science, n. ser.. 23 (1906), No. 585, pp. Ji2J,, 

 Ji25). — A discussion is given of the various ways in which bacteria enter living 

 plants, and some doubt is expressed as to whether certain stomatal infections 

 may not take place through the action of drops of water standing on the plant, 

 causing the destruction of cells underneath the epidermis. While this may 

 account for infection through stomata, it does not remove the possibility of infec- 

 tion through the water pores. The various means by which the bacteria are 

 distributed through the plants are briefly mentioned, and the author states that 

 the transpiration stream appears to have little to do directly with the movement 

 of bacteria in the stems of diseased plants. It appears that in some cases bac- 

 teria are able to pass from cell to cell through the pits or thin places in the cell 

 wall without any extensive solvent action being necessary. Attention is also 

 called to the distribution of starch in young potato tubers affected by Bacterium 

 solanaceariini. This organism has little diastatic action on potato starch, and 

 the irregular distribution of the starch in affected tubers seems to indicate the 

 paralysis or destruction of considerable areas of tissue surrounding the bacterial 

 foci, so that it is impossible for the plant to store up the starch in such cells. 



Cultures of Uredineae in 1905, J. C. Arthur (.Jour. Mycol., 12 (1906), No. 

 81, pp. 11-27). — An outline is given of culture experiments with some 30 species 

 of rusts which have been successfully grown during 100.^. particular attention 

 being called to the plum rust (Puccima pnnii-sjiiiiosd). The author investigated 

 the possilde relationship between JEci<liu)ii pKiictaiinii occurring on various spe- 

 cies of Anemone, llepatica, etc., in the United States and the rust of plums, and 

 as a result of his investigations he arrives .at the conclusion that there is no 

 doubt of the general identity of the American and European plum and cherry 

 rusts and their connection with J^Jcidiuni punctatum. 



Experiments with Puccinia sorghi in 1905, W. A. Keleermais' (.Jour. 

 Mycol, 12 (1906), No. 81, pp. 9-11).— In a previous report (E. S. R.. 1«, p. 787) 

 the author gave a brief account of some experiments with the ni.-iize rust, and in 

 the present publication a summary of previous work is included and the results 

 of his experiments in 1905 are described. 



Attention is called to the discovery of the ppcidium stage on Oxalis by Dr. J. C. 

 Arthur (E. S. R., IG, p. 986), and the author states that by using teleutospores 

 of the maize rust he has been able to secure the oecidium on Oxalis, thus com- 



