380 EXPERIMENT STATION RECORD. 



DISEASES OF PLANTS. 



Report of the government mycologist, J. I». Cakruthers (Admr. Rpts., Roy. 

 Bot. Gardens, Ceylon, 190S, Misc., pt. 4, pp. 5-10).— Considerable attention is given to 

 a disease of tea leaves due to the fungus Pestalozzia guepini. This fungus causes a dis- 

 ease known as "gray blight'" and occasions at times serious losses to tea plantations. 

 Another serious disease of tea is due to the root fungus Rosellinia radiciperda. A third 

 disease which is said to rarely attack tea in Ceylon, though abundant in other dis- 

 tricts, is due to the fungus Marasmius mrmentosus. 



In addition notes are given on the witches' broom of cacao, caused by a species of 

 Exoascus, and rubber canker which are to be discussed in future publications. A 

 brief note is given on the resistance of the spores of Hemileia vastatrix to sunlight, so 

 far the spores resisting the direct action of the sun to a very high degree. 



Annual report on the diseases and injuries of economic plants, A. A. 

 Yacheoski (St. Petersburg: Min. Agr. and Imp. Domain?,, 1904). — This is the first 

 annual record for 1903 of the Central Phytopathological Station, established by the 

 Imperial Botanical Garden. The present record deals with, the diseases of cereals, 

 fodder grasses, garden plants, fruit trees, berries, vines, forest species, orchard and 

 decorative plants, and tropical and subtropical plants. — p. fireman. 



Diseases of cereals, D. McAlpixe [Jour. Dept. Agr. Victoria, 2 (1904), No. 8, pp. 

 709-721, pis. 2, dgm. 1). — In an address delivered before a convention the author 

 describes a number of diseases of cereals, paying particular attention to rust and 

 take-all. He presents statistics to show the losses attributed to rust in Australia, 

 and reviews the various experiments for its control. The most promising method 

 for the control of rust seems to be in the selection of resistant varieties, and a variety 

 known as Rerraf is said to be able to withstand the rust when other varieties along- 

 side of it were almost entirely destroyed. Other promising rust-resisting varieties 

 are mentioned. For the prevention of take-all the author recommends a series of 

 rotations which does not include wheat or other susceptible plants for a number Of 

 years. 



Clover rot, W. Freckmanx ( Deut. Landw. Presse, 31 (1904), No. 5, pp. 452-454, figs- 

 6; Bid. Mens. Off. Kenseignements Agr., 3 (1904), No. 8, pp. 915-918). — A description is 

 given of a clover disease caused by Sclerotinia trifoliorum, which is said to have been 

 quite prevalent in portionsof Europe, causing greatinjury to clover fields. It becomes 

 conspicuous in September and October, when the leavespresent brown spots bordered 

 with yellow, and in about 15 days the entire leaf is affected and finally falls, leaving 

 the plant bare. The development of the fungus is discussed at considerable length. 

 In addition to the ordinary red clover, it has been found to attack crimson, alsike, 

 and white clovers, sainfoin, alfalfa, and other leguminous plants. 



Where a field becomes infested with this fungus it is recommended that the. culti- 

 vation of clover and similar crops be abandoned for a time and the land seeded to 

 grass or given to the cultivation of cereals. If the disease appears to a slight extent 

 in clover fields its effect may be diminished by sowing grass seed, which will gradu- 

 ally replace the clover as it is destroyed and finally result in the production of a 

 meadow. 



A disease of endive (Bid. Mens. Off. Renseignements Agr., 3 (1904), No. 3, pp. 295, 

 296). — A brief account is given of a notice published elsewhere of a disease of endive, 

 which has been quite prevalent in parts of Italy. The disease seems to be caused 

 by the fungus Puccinia prenanthidis, which causes rusted spots upon the leaves, 

 destroying the plant for use as salad. The progress of the disease is said to be quite 

 rapid, the pustules spreading until the leaf is fully involved and later transformed 

 into a worthless mass. 



On account of the use of the plant as a salad, fungicides can not be readily used 

 for its protection. On this account the author recommends careful selection of plants, 



