Lind, Jens, and Ravn, Frederik Kølpin. Forsøg med midler mod byggets stribesyge. Tidsskr. Planteavl 25: 56-116. Litteratur, p. 115-116. 1918. 125. Beretn. fra Stat. Forsøgsvirks. i. Plantekult. Ludwig, Clinton Albert. The effect of tobacco smoke and of methyl iodide vapor on the growth of certain microorganisms. Amer. Jour. Bot. 5: 171–177. Ap. 1918. Literature cited, p. 177. McClintock, James Albertine, and Smith, Loren B. True nature of spinach-b`ight and the relation of insects to its transmission. Jour. Agr. Research 14: 1-60, pl. Jy. 1, 1918. McCubbin, William A. Public school survey for currant rust. Phytopathology 8: 294-297. Je. 1918. Mackie, D. B. Some observations on citrus canker. California Citrograph 3: 231, 244-245. Ag. 1918. List of susceptible varieties, especially in the Orient, cost of eradication in Florida, etc. MacMillan, H. G. Sunscald of beans. Jour. Agr. Research 13: 647–650, pl. 64-66. Je. 17, 1918. Martin, William H. Dissemination of Septoria lycopersici Speg. by insects and pickers. Phytopathology 8: 365–372. Jy. 1918. Literature cited, p. 372. Matz, Julius. Report of the laboratory assistant in plant pathology. Florida Agr. Expt. Sta. Rpt. [1916]/17: 87R-94R, illus. 1918. Pecan dieback, Botryosphaeria berengeriana; an undescribed Gnomonia on pecan leaves. Orton, William Allen. Breeding for disease resistance in plants. Amer. Jour. Bot. 5: 279-283. Je. 1918. Literature cited, p. 284. Pammel, Louis Hermann. Recent literature on fungous diseases of plants. Rpt. Iowa State Hort. Soc. 52: 193 -251. 1918. Pierce, Roy Gifford. Notes on Peridermiums from Ohio. Need of pathological viewpoint in nursery inspection. Phytopathology 8: 292–294. Je. 1918. Reddick, Donald. Lightning injury to grape vines. Phytopathology 8: 298 Je. 1918. Rees, Charles C. The rusts occurring on the genus Fritillaria. Amer. Jour. Bot. 4: 368-373, illus. Je. 1917. Rhoads, Arthur S., Hedgcock, George Grant, Bethel, Ellsworth, and Hartley, Carl. Rosenbaum, Joseph, and Ramsey, Glen B. Influence of temperature and precipita- Kuehneola rosae n. sp. In Japanese, description of species in English. Schoevers, T. A. C. Meer staatsbemoeiing op het speciale gebied van bestrijding van plantenziekten en schadelijke dieren. Cultura 30: 164–171. My. 1918. Seaver, Fred Jay, and Horne, William Titus. Life-history studies in Sclerotinia. Mem. Torrey Bot. Club 17: 202–206, pl. 3. Je. 1918. S. geranii sp. nov. Sherbakoff, Constantin Demetry. Report of the associate plant pathologist. Florida Agr. Expt. Sta. Rpt. [1916]/17: 76R-86R, illus. 1918. Damping off; phomopsis of egg plant; buckeye rot of tomato, Phytophthora terrestria; bacterial spot of pepper; pepper pink joint; other diseases of importance. Smith, Erwin Frink, and Godfrey, George Harold. Brown rot of Solanaceae on Ricinus. Science n.s. 48: 42-43. Jy. 12, 1918. South, F. W. Buried coconut trunks and root diseases of rubber. Agr. Bul. Fed. Malay States 6: 269. Mr. 1918. Stakman, Elvin Charles, Parker, John Huntington, and Piemeisel, Frank Joseph. Can biologic forms of stemrust on wheat change rapidly enough to interfere with breeding for rust resistance. Jour. Agr. Research 14: 111-123, pl. Jy. 8, 1918. Stevens, H. E. Lightning injury to citrus trees in Florida. Phytopathology 8: 283-285, illus. Je. 1918. Report of plant pathologist. Florida Agr. Expt. Sta. Rpt. [1916]/17: 66R 75R, illus. 1918. Citrus diseases—gummosis, melanose, canker, foot rot; some diseases of the season. Stewart, Vern Bonham. Exclusion legislation and fruit tree production. Phytopathology 8: 360-364. Jy. 1918. U. S. Department of Agriculture. Federal Horticultural Board. Quarterly letter of information no. 27, 17 p. Ap. 1918. Service and regulatory announcements. March: 25-38, My. 9; April: 39-52, Je. 18; May: 53-63, Je. 28. 1918. U. S. Department of Agriculture. Bureau of Plant Industry. Plant Disease Survey. Plant disease bulletin 2: 19-41, My. 15; 42–53, Je. 1; 54 65, Je. 15; 66-80, Jy. 1. 1918. Van der Bijl, Paul Andries. A study on a "mottled" disease of the black wattle. Union S. Africa Dept. Agr. Div. Bot. Sci. Bul. 4, 20 p., 9 fig. 1914. Van Fleet, Walter. Hybrids and other chestnuts for blight districts. Rpt. Proe. Ann. Meeting North. Nut. Grow. Assoc. 7:54-57. 1917. Voglino, Pietro. Intorno al marciume radicale del gelso. Bul. Agr. Milan 51, no. 29: [1-2]. Ag. 10, 1917. Weir, James Robert. Forest disease surveys. U. S. Dept. Agr. Bul. 658, 23 p.. illus. 1918. Wilson, Guy West. Studies in North American Peronosporales VII. New and noteworthy species. Mycologia 10: 168-169. My. 1918. Peronospora grisea, P. seymourii, Rhysotheca acalyphae n. sp. Wormald, H. "Brown rot" of apples. Jour. Bd. Agr. [London] 25: 299-302, pl. Je. 1918. Young, Harry C. A method for determining the fungicidal coefficient of lime sulphur and other common fungicides. Ann. Rpt. Michigan Acad. Sci. 19: 221-236. 1917. Bibliography, p. 235–236. Zeman, V. Consideraciones sobre el carbón y la carie de los cereales. Rev. Facult. Agron. y Vet. La Plata 12: 330-340. 1917. [PHYTOPATHOLOGY for September, 1918 (8: 457-506), was issued September 12, 1918. Ginseng growers have long been familiar with certain diseases of the root of American ginseng, Panax quinquefolium L., to which they have given the popular name, rust. While this term has in all probability been used somewhat indiscriminately for diseases of different origin, there can be little doubt that it has to a large extent served to specify a definite root disease which has come into prominence because of increasing losses due to its presence. The disease was first observed by the writer during the summer of 1913 in a shipment of affected roots from Belleville, Washington. It was also noted in 1914, by Rosenbaum on roots from Newtown, Pennsylvania. In the fall of 1915 the writer received a quantity of dryrotted roots from Wausau, Wisconsin, and from Fulton, New York. These latter roots furnished excellent material for a detailed study of the disease. THE DISEASE SYMPTOMS Diseased roots show dark brown, dry lesions, which at first are small and scattered, but at length become more or less widespreading and deepseated (figs. 1 and 2). The surface of the lesion is slightly if at all sunken, except in advanced stages of decay. It is usually smooth but may often be somewhat roughened due to the emergence of the stromata produced by the internal mycelium of the pathogene. In general there are two types of lesions. In the first type the injury is merely superficial and is confined to a few layers of cells immediately 1 The writer wishes to express his thanks for suggestions received in the course of this work from Professor H. H. Whetzel. Thanks are also due Mr. J. G. Koehler of Wausau, Wisconsin, for his kindness in furnishing the ginseng roots required for the investigation. beneath the epidermis. In this case the affected tissue may be readily sloughed off by rubbing it beneath the ball of the thumb, thereby exposing to view the healthy tissue below. This character has undoubtedly given to the disease its popular name of rust. In many cases the root seems to be able to prevent the further ravages of the disease, by cutting off the tissue attacked by the formation of a centripetal cork cambium. In such cases, the decayed tissue sloughs off after a time, leaving peculiar pockings or pittings on the surface of the root. Such roots are frequently observed in gardens where the rust occurs. FIG. 1. SURFACE VIEW OF GINSENG ROOTS ATTACKED BY RUST. (NAT. SIZE) The second type of lesion, instead of being confined merely to the subepidermal cells, extends through the cortex, frequently involving the stele. In many cases the rot extends throughout the entire cross-section of the root, which finally separates at the point of attack, leaving a stub as shown in the root to the right in figure 1. Sometimes the crown of the root together with the bud is rotted, and in others all of the root but the bud is destroyed. In either event the plants fail to develop the following spring. On digging to ascertain the cause of the trouble very frequently |