350 
Journal of Agricultural Research 
Vol. II, No. s 
rest of the tests being performed with fungicides. For the latter, forma¬ 
lin, copper sulphate, cresol, and potassium sulphid were tried. Kafir, 
broom corn, and sorgo were used, and of these the first two developed so 
little infection that the results were of no significance. 
With the more sus¬ 
ceptible sorgos (chiefly 
the Red Amber va¬ 
riety), however, quite 
heavy infections oc¬ 
curred in some sea¬ 
sons. The important 
features of the results 
are brought out in the 
summaries presented 
in figures 3 to 7, in¬ 
clusive. The first and 
last of these figures 
present results ob¬ 
tained with several 
varieties of sorgo, the 
one being a summary 
of treatments per¬ 
formed with hot water 
without presoaking 
and the other a sum¬ 
mary of the whole 
work on seed treat¬ 
ments, including both 
thermal and chemical 
methods. The three 
others (figs. 4, 5, and 
6) show the results 
of modified hot-water 
treatments 1 of Red 
Amber sorgo (S. P. I. 
No. 17548) according 
to the three elements 
of the treatment: fig¬ 
ure 4, according to the 
length of presoaking 
given the seed; figure 
5, according to the duration of the hot-water treatment; and figure 6, 
according to its temperature. 
Fig. 4.— Curves summarizing for different years the percentages of infec¬ 
tion: First, in plantings of Red Amber sorgo after modified hot- 
water treatments at all temperatures and of all durations, but after 
presoakings of various duration; and, second, in control plantings (not 
treated with hot water). 
1 This method was originated by Jensen (1888). See Freeman and Johnson (1909) and Appel and Riehm 
(1911). Tepid water for presoaking was tried in a few of these treatments of sorghum, but without any 
difference in results. 
