244 
Journal, oj Agricultural Research 
Vol. XXX, No. 3 
Table I.— Greenhouse experiments 
showing relative nodulation of different 
varieties of soy beans when inoculated 
with organisms isolated from several 
varieties a 
The field tests were conducted in 
cooperation with the State homes at 
Vineland and Skillman, N. J. Soil 
that had not been planted in soy beans 
for years was selected for the plots. 
Acid phosphate applied at the rate of 
250 lbs. per acre was the only fertilizer 
employed. The inoculations were made 
by applying the organisms directly to 
the seeds. The crop was harvested at 
approximate maturity, the roots of.a 
number of plants being dug in order to 
obtain the nodulation data. The re¬ 
sults of the Vineland experiment are 
reported in Table II. 
The Table II data from Skillman have 
not been reported, but they are practi¬ 
cally identical with those from Vine- 
land. The field tests were limited to 12 
plots each. Organisms isolated from 
Wilkon, Haberlandt, and Mammoth 
Yellow soy beans were used in inoculat¬ 
ing these varieties; uninoculated beans 
were also planted. Since the unin¬ 
oculated seeds gave none, or at most 
but few, nodules, they have not been 
reported on. In the field tests, with¬ 
out exception, Mammoth Yellow pro¬ 
duced the greatest number of nodules, 
Wilson an intermediate number, and 
Haberlandt the fewest. As in the case 
of the greenhouse tests, the varieties 
showed always the same relative ability 
to nodulate, regardless of the source of 
the organism. No data were collected 
which showed a tendency on the part 
of the organism to become adapted to 
a specific variety of soy beans. 
Table II.— Field experiments showing 
relative nodulation of several varieties 
of soy beans when inoculated with 
organisms isolated from the same var¬ 
ieties .“ 
Variety planted 
Average number of nodules 
per plant of soy beans when 
inoculated with organisms 
isolated from— 
Haber¬ 
landt 
Mam¬ 
moth 
Yellow 
Wilson 
Haberlandt. 
20 
18 
22 
Mammoth Yellow. 
40 
45 
- SO 
Wilson. 
30 
26 
24 
« Plants grown to approximate maturity under 
field conditions. 
CONCLUSIONS 
The soy bean Radicicola organism 
does not tend to become adapted to 
specific'host varieties of soy beans. 
The differences in nodulation shown 
by the several varieties of soy beans 
may be due to some physiological dif¬ 
ference in the varieties, possibly a dif¬ 
ference in ability to conduct carbohy¬ 
drates to the roots or-proteins away 
from the roots. 
