158 



Journal of Agricultural Research 



Vol. IV. No. 2 



Table V. — Results of pot experiments with Rhizoctonia ro/— Continued 



UNINOCULATED POTS 



"Two of these beets were diseased with Rhizoctonia rot. One of them eventually recovered, and the 

 other died, 

 b The additional beet is known to have resulted from seed delayed in germination. 



Other inoculations with Rhizoctonia were made on beets growing in 

 the field at Madison, Wis., Garden City, Kans., and Rocky Ford, Colo. 



Of 30 plants inoculated at Madison on July 23, i escaped infection, 2 

 were infected but recovered, and 27 were killed. The fungus was re- 

 covered in culture from several of them. The control plants, of which 

 there were several hundred, remained healthy. 



The inoculations at Garden City were made on July 27 on beets fur- 

 nished by Dr. C. F. Clark, of the Bureau of Plant Industry, who kindly 

 made the field observations. The field was known to be somewhat 

 infected with Rhizoctonia. One row was inoculated, those adjacent on 

 either side being reserved as controls. The same procedure was observed 

 in the inoculations with Phoma betae, previously reported, but since these 

 did not produce disease, five rows, or 150 beets, became available for 

 controls. Of the 30 inoculated plants, 23 were killed, 2 others were 

 so seriously injured at the crown as to become entirely defoliated and 

 apparently dead but developed a few new leaves late in the fall (October) , 

 and 5 escaped infection. The rate of progress of the disease is shown in 

 Table VI. Three control beets became infected during the season. 



