352 EXPERIMENT STATION RECORD. 



it is considered that the fungus secretes an enzym which hydrolyzes xylan to 

 xylose. 



Apple mildew, W. S. Ballard (Abs. in Phytopathology, 5 {1915), No. 5, p. 

 292; Science, n. ser., 42 (1915), No. 10S6, p. 581). — Efforts which have been 

 made to control this disease are referred to, including the use of colloiilal 

 sulphur, prepared by dissolving sulphur in melted resin, grinding, and putting 

 into ammonia water, as well as some of the difficulties involved in the use of 

 Bulphur and the reasons for the use of dilute sprays. 



Coryneum fniit spot of apricots, J. T. Barrett (Abs. in Phytopathology, 5 

 (1915), No. 5, p. 293; Science, n. ser., 42 (1915), No. 1086, p. 582).— A descrip- 

 tion is given of this disease, which is said to be not so widely disti'ibuted on 

 apricots as was supposed. Spraying operations carried out for its control 

 have not been satisfactory in all cases. 



An established Asiatic Gymnosporangium in Oregon, H. S. Jackson (Abs. 

 in Phytopathology, 5 (1915), No. 5, p. 293; Science, n. ser., 42 (1915), No. 1086, 

 p. 582). — The author reports the results of .studies and inoculations with a 

 newly imported Gymnosporangium discovered on oriental pears in Oregon. 



Observations on prune rust (Puccinia pruni-spinosae) in southern Cali- 

 fornia, J. T. Baekett (Abs. in Phytopathology, 5 (1915), No. 5, p. 293; Science. 

 n. ser., 42 (1915), No. 1086, p. 582). — This fungus is said to be serious at times 

 in southern California on apricots and peaches. In some cases early fall prun- 

 ing has stimulated fall growth in which foliage stays alive through the winter, 

 and rust development in Oils foliage has caused early spring infection with 

 very detrimental effects to orchards. 



A Nectria and its Fusarium generation on raspberry roots, A. Oster- 

 WAI.DEB (Landtc. Jahrb. Schiceiz, 29 (1915), No. 1, pp. SO, 31).— It is stated that 

 the fungus, N. ruhi, noted as apparently parasitic on roots of the raspberry 

 (E. S. R., 26, p. 450) has been studied In pure cultures and by means of infec- 

 tion tests on healthy roots both wounded and uninjured, but without result 

 as regards proof of its really parasitic activity. The author also notes the 

 view of WoUenweber (E. S. R., 30, p. 537), according to which this fungus is 

 classed as Hypomyces rubi. 



Preliminary note on some sprays for American gooseberry mildew, J. M. 

 Hector and S. J. M. Auld (Card. Chron.. 3. ser., 58 (1915), No. 1493, pp. 79, 

 80). — The authors state that under the conditions obtaining In these preliminary 

 tests the action of American gooseberry mildew Is checked by the use of col- 

 loidal sulphur (prepared by precipitnting lime sulphur with acid in the pres- 

 ence of gelatin under suitable conditions), precipitated lime sulphur, various 

 lime sulphurs, and soda. The.se sprays se^-med also to delay the formation of 

 the perithecia. The treatments are undergoing further trial. 



Beports of the commission on control of American gooseberry mildew, 

 W. T. C. VAN DooRN ET AL. (Tuinbouw, 2 (1914), ^o. 36. pp. 429-431; 3 (1915). 

 No. 27, pp. 301-304). — Tests in 1914 with two preparations reported only by 

 number, gave good results in reducing attack by American gooseberry mildew. 

 The " California mixture " lessened attack, but the bushes suffered from leaf 

 cast and the size of the fruits was decreased. A preparation designated as 

 " Nasfa " lessened attack somewhat, but was associated with a characteristic 

 form of injury. 



The 1915 tests showed less favorable results from the first two preparations 

 mentioned above. 



Recent studies on infection of grape by Plasmopara (Peronospora) viti- 

 cola, H. MtJLLER-THUBGAU (Laixdw. .Jahrb. Schiceiz, 29 (1915), No. 1, pp. 26- 

 28). — Reviewing the results of studies previously noted (E. S. R., 28, p. 244) 

 tending to show that proper application of fungicides to the lower or stomatal 



