746 EXPERIMENT STATION TSECORD. 



with suggestions for their control. The different diseases are grouped according 

 to the liost plants under the followlnii heads : Field crops, grasses, garden plants, 

 A'egetahles. and fruit trees. 



Report of assistant in botany and horticulture, H. S. Fawcett {Florida 

 Sta. Rpt. 1906, pp. XXI-XXVII). — Notes are given on a number of diseases of 

 plants that have been under observation during the past year, and a brief 

 account of a study of the fungus parasites of the wliite fly, which is proving 

 very destructive in orange groves. Among the more important plant diseases 

 noted are authracnose and wilt of beans, leaf blight of cantaloupes, rust of 

 celery, scab and wither tip of citrus fruits, cucumber mildew, mango bloom 

 blight, peach crcnvn gall, and tomato leaf blight, leaf mold, wilt, and bacterial 

 blight. For the prevention of most of these diseases thorough spraying with 

 Bordeaux mixture has proved successful. 



Annual report of investigations on plant diseases, M. Hollrung et al. 

 (Jahresber. Pflanzenkraiilc. 8 (IDO,')). pp. YlII+3.',0).— This report, published 

 in 1907, gives a review of the literature relating to plant diseases and insect 

 injuries issued during 1905, about 2,200 articles being noted by abstract or 

 otherwise. The arrangement of the topics is essentially the same as that previ- 

 ously given (E. R. R.. 12, p. (J.oS). 



Root diseases of sugar beets, L. Peters {(•mschaii, 11 (1907), Xu. 5, pp. 

 85-87, flfffi. .'/). — The author describes diseases of sugar-l)eet seedlings due to 

 Pythium debaryainnti, Plioma hcltr, and Aphaiiomi/ccfi hrrifi. The methods of 

 attack and the effect upon the host plants are described, after which notes are 

 given on the prevention of these diseases, the means suggeste<l including treat- 

 ment of the seed with fungicides, soil treatments, etc. 



The occurrence of alumina and iron oxid in diseased beets, II. Pellet 

 (Sucr. Indig. ct Colon., 69 (1907), Xo. '>. pp. 118-120). — In his investigations 

 regai'ding the bacteriosis of sugar beets (E. S. R.. 12. p. 4.")8) Stiff has shown 

 that as a result of disease the ash content as well as the proportion of iron oxid 

 and ahnnina are increased 



The author has reviewed the experiments of Stiff and carried on investiga- 

 tions with beets attacked by the heart rot {PJiouia hctw). He has confirmed 

 the previous investigations in that his analyses of the asli of the diseased por- 

 tions of the roots showed a decided increase in the percentage of ash and a 

 higher amount of iron oxid and alumina. These amounts were found to fluc- 

 tuate widely in different specimens, and the author believes that the increase is 

 not directly due to the disease, but that the roots are rendered much more 

 spongy by reason of the fungus attack. Consequently the fine particles of the 

 soil adhere to them and are not removed in tlie ordin.-iry jirocess and scrul>bing 

 preliminary to analysis. 



A fungus disease of greenhouse lettuce, J. B. Dandeno (Rpt. Mich. Acad. 

 Sci., 8 (1900), PI). J.7-J7. fiijN. 2). — A brief account is given of a disease of green- 

 house lettuce, which is reported as being caused by Marsonia perforans. This 

 fungus causes characteristic perforations in the leaves and is frequently very 

 troublesome in lettuce houses. A study by the author has led him to the con- 

 clusion that the fungus has been wrongly referred, and he proposes for it the 

 name Didymaria perforans, a technical description of which is given. 



Some notes on the destruction of plum trees, E. Rabat^ (Semaine Agr. 

 [Paris], 26 (1907). No. 1339. pp. J,29. //50).— According to the author, there 

 has been known in France for many years a peculiar disease of plum trees 

 which is app.'irently becoming more frequent. Tlie affected trees are covered 

 with ginn, the flowers are aborted, and the tips of the young branches are 

 dead. Later the withered appearance of the branches descends to the trunk. 



