110 



PLASMODIOPHORALES 



Tillantin B in solution sprinkled over seed beds 

 gives complete control, according to Mothes ('25). 

 Hertel ('26), however, reported that 20 gms. per 

 10 1. water poured over each plant or used as dust 

 in conjunction with uspulun are ineffective. Like- 

 wise, tillantin B dust alone (100 to 150 gms. per 

 sq. m. of soil) has no effect on club root, according to 

 Blunck ('28). 



Cheshunt compound, clubicide, and 0.2 per cent 

 h/sol are ineffective, according to Preston ('28). 

 Carbon bisidphide when applied to the soil is also 

 ineffective (Miiller and Osterwalder, '24). 



Copper sulphate powder applied at the rate of 

 600 and 1.200 lbs. per acre (Halsted, '96), or as a 

 solution (1:1,664, 1 gal. per .30 ft. row) directly to 

 growing plants (Glo3'er and Glasgow, '24) has no 

 effect on club root. Miiller and Osterwalder ('24) got 

 similar negative results. 



Bewley's solution (2 oz. copper sulphate and am 

 monium carbonate) applied in a concentration of 1 

 oz. to 2 gal. water increases infection (Gloyer and 

 Glasgow, '24). 



"Hochst mittel," according to Hertel ('26) re- 

 duces infection considerably, but Blunck ('28) 

 found that 150 gms. per sq. m. of soil is ineffective. 

 He also found Elhardt's Wurzelschuts and ftorium 

 (150 g. per sq. m.) to be of little value against club 

 root. 



Copper carbonate is reported to be fairly effective 

 by Naumov ('27) and an anonymous worker in the 

 U. S. ('22), but Vladimirskaya ('30) got only par- 

 tial control with it. 



Red copper oxide is fairly effective, according to 

 Naumov ('27) and McLeod and Howatt ('34). 



Lime copper dust increases infection, according to 

 Gloyer and Glasgow ('34). 



Sodium carbonate, 3,000 lbs. per acre is ineffec- 

 tive, according to Halsted ('96). Lindfors ('24) 

 confirmed Halsted's results, but Naumov ("27) and 

 Vilkaites ('33) found it to be slightly effective. 



Bordeaux mixture alone in amounts up to 5,280 

 gals, per acre or mixed with corrosive sublimate has 

 little or no effect on club root, according to Halsted 

 ('96, '99), but later an anonymous worker (U. S. A., 

 '22) reported it to be effective. 



Sodium chloride, 300 to 600 lbs. per acre, has no 

 appreciable effect on club root, according to Hal- 

 sted ('96). Naumov ('97), however, found that cal- 

 cium and barium salts (KmCO;,, NaOH, KOH, and 

 Ba(OH)o) are to some degrees effective, while 

 CaCU and BaCU are of little value. Wellman ('30), 

 on the other hand, reported that K'^COs does not in- 

 hibit club root. 



Radium, x-rai/, and ultraviolet light treatments 

 are reported by Petri ('24) to be effective in reduc- 

 ing club root infection. 



LIMING 



Liming the soil before planting appears to be the 

 most widely used and practical control measure in 

 the field, although numerous workers have failed to 

 secure satisfactory results by such treatment. Who 

 first discovered the efficacy of lime is not known, but 

 Ellis reported that before 1742 farmers in England 

 had been using clay or marl for dressing diseased 

 fields before planting turnips. In 1831 Farquahar- 

 son advocated the addition of powdered lime shells 

 to manure before using, while Abbay (1831) recom- 

 mended the addition of 256 bushels of "knottingsley" 

 lime per statute acre as a control measure. Subse- 

 quent workers, including Anderson ('55), Hunter 

 ('57), A. Voelcker ('59), and Henderson ('67), of 

 this early period also noted the great prevalence of 

 club root in lime-free soils and reported varying de- 

 grees of control with the addition of lime, ground 

 oyster shells, and flour of bone to the soil, but they 

 found tliat the effectiveness of these substances varied 

 markedly and that all kinds of lime were not equally 

 effective. At the close of the 19th century numerous 

 other pathologists, including J. A. Voelcker ('94), 

 Evcleshvmer ('91), Sommerville ('94-97), Massee 

 ('95), Halsted ('96-99), Seltensperger ('96), Pot- 

 ter (■96-'97), Sitensky ('98), Gilchrist ('98-'00), 

 L. R. Jones ('01 ), and others reported varying bene- 

 ficial results from the use of lime. Halsted. in par- 

 ticular, carried out an extensive series of tests in 

 America, and after seven years of field experimenta- 

 tion concluded that air-slaked lime at the rate of 75 

 bushels per acre was commercially satisfactory as a 

 control measure. Later, however, Cunningham ('14) 

 reported that 150 bu. per acre were necessary for 

 effective control. Extensive experiments along the 

 same line were carried out in Denmark by Ravn and 

 his associates ('02-'ll) with calcium carbonate and 

 calcium oxide in quantities varying from 2.5 to 

 nearly 10 tons per acre. They found that the largest 

 treatments were the most effective, and although in- 

 fection still occurred the crops produced were com- 

 mercially satisfactory. Following these long-time ex- 

 periments of Halsted and Ravn, beneficial results 

 from the use of lime in the field have been reported 

 by numerous workers, including the following: Dia- 

 kanoff ('11), Brick ('13), Cunningham ('14), 

 Georgeson ('16), Bos ('18), Weiss ('18), Popp 

 ('19), Miiller-Thurgau and Osterwalder ('19, '23). 

 Janson ('20), Whitehead ("22, '36), Jorstad ('23). 

 Katterfeld ('23), Harter and Jones ('23), Bremer 

 ('23-24), Hollrung ('23), Anony. (Nova Scotia, 

 '23), Montietli ('24), Darnell-Smith ('24), Lind- 

 fors ('24), Kindshoven ('24), Naumov ('25, '27), 

 Tennent ('25, '30), Siemaszko ('25), Riehm ('25). 

 Gleisberg ("26), Tessenow ('26), Vaughan and 

 Wellman ('26), Appel ('27), Chupp ('28), :Martin 

 ('28, '34), Blunck ('28), Wellman ('30), Rabbas 

 ('30), Gibhs ('31, '32), Anony. (Germany, '31), 

 Kreuzpointer ('31), Beaumont and Staniland ('33, 

 ■34), Nielsen ('33), Wilson ('34), Potts ('35). 



