844 EXPERIMENT STATION RECORD. [Vol. 35 



DISEASES OF PLANTS. 



The control of experimental conditions in phytopathological research, A. A. 

 Potter (Phytopathology, 6 (1916), No. 1, pp. 81-88). — The author calls attention 

 to the necessity for the improvement of methods of phytopathological research in 

 order that experiments may be more definitely controlled. 



Effect of meteorological conditions on development of plant diseases, II, 

 G. N. DoROGiN (Mat. Mikol. i Fitopatol. Ross., 1 (1915), No. 4, pp. 3-5, fig. l).-— 

 This is the second report (E. S. R., 34, p. 840) on the meteorological conditions 

 in the region of Petrograd in connection with plant diseases. It covers the 

 spring months of 1915. 



Report of the assistant plant pathologist, C. D. Sherbakoff (Florida Sta. 

 Rpt. 1915, pp. XCIV-XCVIII).—A brief report is given of investigations begun 

 by the author, the principal ones being in connection with seed bed diseases of 

 celery and tomatoes. While a number of diseases of these truck crops are de- 

 structive in parts of Florida, the work has been carried on chiefly with damping 

 off. This, the author thinks, is due to several organisms, among them a Rhizoc- 

 tonia, a Fusarium, a species of Gloeosporium, and Sclerotinia libertiana. Brief 

 notes are given on the prevailing fungus diseases of a number of vegetables. 

 These include lettuce drop, early blight of celery, Phomopsis of eggplants, 

 Cercospora spots of peppers, cucumber rust, and tomato rust. 



Notes on parasitic fungi in Wisconsin, I, II, III, J. J. Davis (Trans. Wis. 

 Acad. Sci., Arts, and Letters, 18 (1915), pt. 1, pp. 18-109, 251-211).— The three 

 parts of this contribution are supplemental to a provisional list and give some- 

 what detailed discussion of a large number of forms. Some of these species 

 are claimed to be new, while others are provisionally so considered. Several 

 species not previously reported for Wisconsin are listed, also additional hosts 

 of these fungi. Alphabetical indexes of hosts are also given. 



On fungus parasites of cultivated plants, V. Kazanovskii (Khoziaistvo, 

 1915, p. 696; ahs. in Mat. Mikol. i Fitopatol. Ross., 1 (1915), No. 4, p. 124).— U 

 is stated that many Russian varieties of wheat and a minority of introduced 

 ones are attacked by yellow rust. 



A survey of plant parasites in 1913 in the Province of Tula, N. P. Tbusova 

 (Mat. Mikol. i Fitopatol. Ross., 1 (1915), No. 4, pp. 35-56).— During the wet 

 summer of 1913 in the Province of Tula, Russia, the author observed 152 differ- 

 ent diseases on cultivated, and 102 on wild, plants. These include many well- 

 known fungus enemies of field and forage crops and of garden, orchard, and 

 forest plants. Several new species are also described. 



New species of mycoflora in the Province of Astrakhan, found in 1914, 

 S. Shembel (Szembel) (Mat. Mikol. i Fitopatol. Ross., 1 (1915), No. 4, pp. 

 107-112, figs. 10). — The author gives descriptions of four species which are con- 

 sidered as new and named respectively Didymosphwria (Didymclla) alhaginis 

 on Alhagi camelorum, supposedly the winter stage of Septoria alhaginis, previ- 

 ously reported by the author (E. S. R., 34, p. 842) ; Rhabdospora dodartice and 

 Hendersonia dodartice on Dodartia orientalis; and Cercospora zygophylli on 

 Zygophyllum fabago. 



A Gymnosporangium with repeating spores, J. C. Arthue (Anier. Jour. 

 Bot., 3 (1916), No. 1, pp. 40-45, fig. 1). — Evidence is presented and discussed 

 regarding the supposed identity of Uredo nootkatensis and /Ecidium sorbi, the 

 name proposed for the new combination being O. nootkatensis. 



The physiological relation of the powdery mildews to their hosts, G. M. 

 Reed (Missouri Sta. Bui. 14 1 (1916), p. 25). — A brief summary is given of in- 

 vestigations of powdery mildews in relation to their hosts, 22 varieties of wheat 

 having been tested, all but 3 of which gave 100 per cent infection. Two varieties 



