2 5 8 
Journal of Agricultural Research 
Vol. I, No. 3 
Experiments Nos. 4, 5, 6, and 7.—On November 18 four sets of inoculations were 
made of 10 plants each (40 plants in all) with organism No. 101 (culture No. 8 of Oct. 
31), as follows: (No. 4) By smearing pycnospores on the leaves and spraying the 
foliage with spores suspended in sterile water and covering the plants with bell jars 
for 24 hours, (No. 5) by smearing pycnospores on the base of the stem, (No. 6) by pour¬ 
ing pycnospores suspended in sterile water about the plants, and (No. 7) by insert- 
ing pycnospores and hyphae into the base of the stem. Six plants were left as checks. 
Results.—(No. 4) No infection. (No. 5) On December 30 one plant, on January 
8 one, on January 13 two, on January 15 one, on January 23 one, and on January 
30 one, or a total of seven plants, were infected. Pycnidia were abundant on all 
when lifted. (No. 6) On December 26 one plant, on December 30 one, on January 
4 two, on January 6 one, on January 10 one, and on January 13 one, or a total of seven 
plants, were infected. The infected plants were lifted on January 24 and pycnidia 
were present on all. (No. 7) On December 21 two plants, on December 26 one, on 
December 28 two, on January 6 one, on January n one, on January 13 one, on January 
14 one, and on January 17 one, a total of ten plants, or all of those inoculated, were 
infected. Pycnidia were present on nine of these plants when lifted and developed 
on the other one after three days in a moist chamber. None of the checks were 
diseased. The experiment was terminated on February 27. 
Experiment No. 8.—On December 9 six 5-weeks-old sweet-potato plants in pots 
were sprayed with pycnospores and hyphae of organism No. 101 (culture No. 1 of Nov. 
12) suspended in sterile water. The plants were covered with bell jars and shaded 
with paper for 24 hours. Six plants were left as checks. 
Results.—No infection. The experiment was terminated February 27, 1913. 
Experiment No. 9.—On December 28 eight 4-months-old sweet-potato plants 
grown in pots were inoculated by inserting pycnospores and hyphae of organism No. 
100 (culture No. 2 of Dec. 10) into the base of the stem. Six plants pricked with a 
sterile needle were left as checks. 
Results.—On January 23 one plant, on February 4 one, on February 7 three, and 
on March 8 one, or a total of six plants, were infected. The checks remained healthy. 
Pycnidia were present on all the infected plants when lifted. The organism was 
recovered from two of the infected plants. The experiment was terminated March 27. 
Only young plants were used in the first eight experiments. Experiment No. 9 
was made with old plants (as compared with those used in experiment No. 8) for the 
purpose of determining whether they were as susceptible as young ones to the foot rot. 
The results indicate that they are. 
Experiment No. 10.—On January 23, 1913, six sweet-potato plants (three old and 
three young) grown in pots were sprayed with pycnospores of organism No. 100 
(culture No. 3 of Dec. 28) suspended in sterile water. All the plants were making 
a good growth. As soon as the plants were sprayed, they were covered with bell jars 
and manila paper for 48 hours. Six plants were left as checks. 
Results.—None of the plants were infected. The experiment was terminated 
March 27, 1913. 
Experiments Nos. ii and 12.—On January 17 ten young plants, each of Ipomoea 
purpurea (E.) Roth, and Ipomoea hederacea Jacq. were inoculated with organism No. 
100 (culture No. 4 of Dec. 28). Seven plants were left as checks. 
Results.—No infection. 
Experiment No. 13.—On December 2 five young plants of Ipomoea coccinea L. 
in pots were inoculated at the base of the stem with organism No. 101 (culture No. 2 
of Nov. 12). Five plants were left as checks. 
Results.—On February 28, 1913, three plants were infected. The organism from 
two of the plants was recovered by pouring plates from the pycnidia and from the 
third plant by planting bits of diseased tissue in plates of synthetic agar. 
