1921] 
MATSUMOTO—SPECIALIZATION IN RHIZOCTONIA 48 
general, when the strains attack such old seedlings as were used 
in this experiment, no pronounced symptoms are observed. 
In spite of the lesions mentioned most of the plants seemed to be 
quite healthy. However, such plants have a tendency to break 
easily in the region of the infected part. 
Experiment 3 (Inoculation of navy beans with the six strains).— 
Seeds used for the experiments were soaked in 10 per cent Javelle 
water for 2 hours and dried at room temperature. The seeds 
were sown with the mycelium of the 6 strains in sterilized pots. 
The final observations were made after 3 weeks, and are given 
below. 
TABLE XXVIII 
INOCULATION OF NAVY BEANS 
P1 P4 P7 B1 H B3 | Check 
Seeds used 20 20 20 20 20 20 20 
Seeds germinated 2 9 11 8 1 10 10 
Number damping off 2 0 0 1 1 0 0 
TABLE XXIX 
INOCULATION OF LETTUCE 
P1 P4 P7 B1 H B3 | Check 
Number of plants used 12 11 12 12 12 12 12 
Number damping-off 9 2 0 4 11 0 0 
Experiment 4 (Inoculation of lettuce with the six sirains).— 
Young plants, 2 inches high, were inoculated with the 6 strains 
by placing some mycelium obtained from potato cultures of the 
same age near the plants about one-third inch below the surface 
of the ground. For 2 days all the plants were covered with 
wet newspaper, and the results above are after 10 days. 
Experiment 5 (Inoculation of potato tubers with the six strains). 
—The tubers were sterilized with formalin and inoculated with 
