It is noteworthy that often great numbers of beet seedUngs are diseased, 

 and yet frequently perfectly healthy plants may be formed close to the dis- 

 eased ones. It should be emphasized further that, when the disease develops at 

 all it is found simultaneously in all parts of the field, and that, as a rule, iso- 

 lated spots are not attacked in the middle of diseased fields. As the plants be- 

 come older, the rootblight ceases. The healed plants usually, however, remain 

 below the healthy ones in size and sugar content and show a tendency to- 

 ward root splitting and other deformities. Stoklasa^ emphasizes the fact 

 that all varieties are not equally susceptible to rootblight. 



The disease has been known since the increase in beet culture in the 

 30's of the last century and, according to Stift^, the discussion as to the 

 cause of the phenomenon began in 1858 at the meeting of the beet sugar 

 manufacturers of the Zollverein. At that time the opinion was expressed 

 by practical growers that the trouble was due to the physical condition of 

 the soil, i. e., a too great solidity of the soil. It was emphasized that root- 

 blight was found only where the upper surface of the soil was bard and had 

 not been loosened on which account a thorough cultivation and stirring were 

 advisable. 



At the time scientists took up the question, the parasitic theory was 

 already at the crest of its development. At first Julius Kiihn in 1859 gave 

 expression to the opinion that the moss button beetle (Atomaria linearis 

 Stephn.) attacked the plants, and, where it had eaten, the rootblight made its 

 appearance. I have observed something similar^. The centipede and such 

 animals were also cited as causes. This theory which prevailed for many 

 years was first upset when Hellriegel found that the disease could be pro- 

 duced without animal injury and in many cases came from the beet- 

 seed. As a result he advised a soaking of the beet-seed for 20 hours in a 

 one per cent, carbolic acid solution*. Karlson, at about the same time, 

 ascribed the phenomenon to a special fungus and in this emphasized the fact 

 that only weak specimens succumbed to rootblight. Seedlings from very 

 good seed or those which were strengthened by an energetic growth, would 

 not be overcome by the fungus carried in these seed balls (Scleranthus)^. 

 The experiments in sterilizing with carbolic acid and with copper sulfate 

 showed a decrease of the'rootblight. In spite of the advantage due to ster- 

 ilization, Karlson lays especial stress on the selection of especially strong 

 seedlings and lays the responsibility for the spread of rootblight on our 

 present cultural methods*', which aim only at obtaining large amounts of 

 seed and neglect the quality. 



1 Stoklasa, Jul., Wurzelbrand der Zuckerriibe. Centralbl. f. Bakteriologie. Sec- 

 tion II, 1898, p. 687. 



~ Stift, Anton, Die Krankheiten der Zucl\:ei-riibe. Wien 1900. Verlag des Cen- 

 tralver. f. Riibenzuckerindustrie. 



3 Zeitschr. f. Pflanzenkr., 1892, p. 278. 



4 Hellriegel, Ueber die Schadigung junger Riiben durch Wurzelbrand etc. 

 Deutsche Zuckerindustrie, Jalirg. XV, p. 745. Biedermann's Centralbl. 1S90. p. 647. 



f* HoUrung also found a lesser degree of disease in sowing large beet seed balls 

 (Scleranthus). Dritt. Jahresb. d. Versuchsstat. f. Nematodenvertilgung. 1892. 

 6 Blatter fiir Zuckerriibenbau, 1900, No. 17. 



