986 EXPERIMENT STATION RECORD. 



with powdered bisulphid of soda are recommended as preventive treatments. The 

 application of dry fungicides is said to be preferred to ordinary sprayings as being 

 less liable to scatter the spores of the fungus. 



The must from diseased grapes should receive the same treatment as is recom- 

 mended above for cuttings and dried fruits. 



Experiments in controlling- black rot in Loire, L. Rougier (Rev. Vit., 24 

 (1905), No. 628, pp. 713-719). — Descriptions are given of a number of experiments 

 carried on for the prevention of black rot of grapes. The use of acetic acid added 

 to fungicides has been recommended, and the author undertook to determine the 

 amount of this acid that would be dangerous to plant growth. It was sprayed upon 

 grapes in various concentrations alone and with neutral copper acetate. As a result 

 'of the investigations the author finds that the disease could be successfully con- 

 trolled by the use of an acidulated copper acetate. 



A new disease of grapes, G. de Istvanffi (Ann. Inst. Cent. Ampelol. Roy. Hon- 

 grois, 3 (1905), No. 3, pp. 167-182, pi. 1). — In 1900 a disease of grapes was observed 

 in Hungary that superficially resembled an attack of black rot on the foliage. An 

 examination showed that it was in no way associated with the black rot, but was due 

 to a distinct fungus, Phyllosticta bizzozeriona. Since its first observation the disease 

 has spread, but most injury is noted in the original center. The fungus attacks the 

 leaves only, never being observed on the fruit, and it has no relation to the black 

 rot, but is often associated with the anthracnose, the two fungi seeming to work 

 together. 



Frequent and thorough treatment with fungicides such as are recommended for 

 grape mildew is suggested, and on account of the association with anthracnose, late 

 autumn and early spring treatments for preventing anthracnose are advised. All 

 European varieties of grapes as well as the variety Isabella seem subject to attack. 

 A technical description of the fungus is given, and its relation to other species of 

 Phyllosticta is discussed. 



The bud rot of cocoanuts, J. H. Hart (Trinidad Bot. Dept., Bid. Misc. Inform., 

 1905, Xo. 48, pp. 242, 243). — A summary is given of the author's observations regard- 

 ing the bud rot disease of cocoanuts. The evidence presented seems to indicate that 

 the disease has been present on the plantation examined for a great many years, as 

 there is a succession of trees which have been planted on areas vacated by the 

 destruction of former occupants. 



A preliminary microscopical examination showed bacteria present in great quan- 

 tity, especially in the heart or growing portion of the tree. The specimens examined 

 were found to be infected from the ground upward, and when the stem was cut 

 through a ring of red discoloration was found between the woody exterior and the 

 interior parts of the stem. This discoloration became more prominent as it reached 

 the growing points and appeared especially to affect the base of the leaf stalks and 

 the spathes inclosing the flowering organs. Eventually these portions become badly 

 infested, the leaves fall, and the tree dies. 



From previous descriptions of diseased cocoanut trees from various sources the 

 author believes that there is little doubt as to the identity of the disease under exam- 

 ination. So far he has been unable to find that there was any relation between the 

 occurrence of the disease and the injury done by the palm beetle (Rhyncophorus 

 j)abnarum) . In addition to bacteria, numerous fungi are to be found in the diseased 

 stems, and further investigations will be necessary to determine the true cause of the 

 disease and methods for its control. 



Cacao diseases (Bid. Dept. Agr. [Jamaica'], 3 (1905), No. 12, p. 270).— A brief 

 account is given of the disease of cacao due to the fungus Phytophthora omnivora. 

 The presence of this fungus may be recognized by the darkening of the pods and the 

 occurrence of a delicate white mold on the outside. 





