864 EXPEEIMENT STATION EECORD. 



germ as that which causes the tomato disease, and that this disease also occurs in 

 Capsicum annum, although neither of these cases has been confirmed by inoculation. 



A series of experiments to determine the manner in which Bacillus solanacearam 

 finds entrance resulted in the conclusion that uninjured tomato plants can not be 

 infected, and that when the bacteria do gain an entrance by way of the water pores, 

 they get no farther than the air spaces immediately below the water pores. The 

 germ gains entrance most commonly by means of injuries to the roots caused by the 

 attacks of parasites or by careless planting. For this reason the author considers the 

 bacillus to be a secondary rather than the primary cause of the tomato disease. A 

 wound of some kind is believed to be in every case the primary cause. This may be 

 caused by (1) careless planting, (2) climatological influences, (3) chemical and 

 physical condition of the soil, and (4) attacks of parasites. In the last class are 

 included all attacks by fungi, insects, and nematodes. Infection most commonly 

 follows the attacks of nematodes. As preventive measures, greater care in planting 

 and the destruction of the Heterodera are urged. Since the latter is, however, 

 almost impossible, it is suggested that the tomato be grafted on a solanaceous stock 

 that is resistant to the attacks of Heterodera. — h. m. pieters. 



A bacterial disease of potatoes, G. Delacroix {Comi)t. Rend. Acad.' Sci. Paris, 

 133 {1901), No. 9, pp. ^i7--^i5).— Attention is called to a bacterial disease of the 

 potato which has been observed in central and western France, being more or less 

 widely distributed through 13 departments. The disease, which is described, is 

 believed to be that caused by Bacillus solanacearum, an account of which was given 

 in U. S. Dept. Agr., Division of Vegetable Physiology and Pathology Bui. 12 (E. S. 

 R., 8, p. 895). This disease is said to be quite distinct from that described by the 

 author under the name gangrene, which is said to be caused by Bacillus caulivoris. 

 As suggested methods of treatment the author recommends the rotation of crops in 

 which potatoes or allied plants shall not occupy the soil for a number of years. 



A bacterial disease of beets, M. C. Potter [Centhl. Bakt. u. Par., 2. AhL, 7 

 {1901), Nos. 8, pp. 282-2S8; 9-10, pp. 353-362, figs. 6).— This article has been pre- 

 viously noted from another source (E. S. R., 13, p. 467). 



The finger-and-toe disease of turnips {Trop. Agr., 20 {1900-1901), p. 258). — 

 The occurrence of the finger-and-toe disease, or club root, of turnips is mentioned 

 and the writer states that its ravages seem to be increased by the use of superphos- 

 phate manures or upon soils subject to short rotations. In his experience, land 

 which had been sown to grass for 8 or 9 years, and afterwards cultivated in turnips, 

 grew a crop without any diseased roots. Where the fields had been in grass for but 

 3 years the turnip crop was practically ruined, showing that the fungus remains in 

 the soil for a longer time than 3 years. 



Observations on root rot (Dongkellanziekte), J. D. Kobus {Meded. Proefstat. 

 Oost Java, 3. ser., 1901, No. 25, pp. 11). — Formerly many diseases were known by 

 this name, but since 1897 the use of the name has l)een confined to a single well- 

 characterized disease. At the East Java station it has been proved that the trouble 

 is not due to differences in the chemical composition of the soil, and that the disease 

 is not inherited. The method of working the soil is, however, of importance. Shal- 

 low planting or planting in loose soil tends to increase the disease, while a heavy 

 application of nitrogenous fertilizer delays or prevents its appearance. Irrigation 

 after the west monsoon has likewise been found helpful in overcoming the disease. 

 The mud deposited from the irrigating water appears to exert a beneficial effect, but 

 the reason for this is not understood since the amount deposited is too small to have 

 any appreciable influence either on the fertility or on the mechanical structure of 

 the soil. One of the most promising fields of work is the development of resistant 

 varieties. Some varieties are already known to be nearly or quite free fi'om the 

 root rot, but these are poor in sugar content. — h. m. pieters. 



