Treatment of Cotton Seed 
1 o 
of treatment which can be used at will to effectually destroy all seed-borne 
infection. It is the purpose of the present paper to present such a treatment 
for the elimination of cotton anthracnose from infected seed. 
TREATMENT OF INFECTED SEEDS WITH DRY HEAT 
Within the last two decades, investigators interested in the control of 
plant diseases have attempted to eliminate seed-borne infection by the 
application of heat, hoping to discover a differential tolerance of the seed 
and the invading fungus. In this work, both dry and moist heat have 
been employed with varying degrees of success. In 1908, Kuhle 22 stated 
that he was able to free barley of loose smut infection by the use of dry 
heat, but was only partially successful in eliminating wheat smut. By 
first drying wheat and barley seeds for short periods at successively higher 
low temperatures then finally subjecting them to dry heat at 90° C. to 
110° for ten minutes, Stormer 31 decreased greatly the amount of loose smut 
on barley, but accomplished very little decrease of wheat smut. Tempera¬ 
tures of 80-100° applied for 45 minutes resulted in little or no reduction 
of smut in summer wheat and summer barley. 32 In 1911, Appel and Riehm 1 
treated smut-infected seeds of wheat and barley by soaking them for 
periods of 2 to 8 hours then heating them for 10 minutes in water at 
4S-50° C. In the cas« of the longer periods of soaking, the per cent of 
smut was markedly reduced. In other trials, it was found that better con¬ 
trol was obtained by heating in water for 10 minutes at 54-56° C. No 
disease developed when seed were permitted to imbibe about 17 per cent 
of water and were then heated for 20 minutes in an oven at 55-60° C. In 
1916, Naumov, 25 attempting to develop a treatment for cereal seeds in¬ 
fected with fungi (Gibberrella saubinetti, Fasarium roseum ' and 
F. subulatum ) believed to be the cause of the condition known in Russia 
as “intoxicating bread,” heated rye at 66° C. and wheat, oats and barley 
at 60° C. for periods ranging from 24 hours to 3 days. He believed that 
by this method he was able to kill these seed-borne fungi without reducing 
the germinability of the seed. Atanasoff and Johnson, 2 however, in tests 
with scab of wheat and barley were unable to verify Naumov’s experiments. 
However, when they subjected wheat, rye, oats and barley to treatment with 
dry heat at a temperature of 100° C. for 30 hours, they found that these 
seeds withstood the prolonged treatment remarkably well, the reduction of 
germination ranging between 10 and 40 per cent exclusive of a very few 
extreme cases. Moreover, seed-borne infections of the bacterial blight of 
oats and barley were killed and wheat scab and spot blotch of barley 
practically eliminated by this treatment. Also, the Helminthosporium blotch 
diseases and the loose smuts of oats and barley were greatly reduced. 
In 1922 Blodgett 14 heated Bliss Triumph potato tubers infected with mosaic 
in water at temperatures from 35 to 80° C. for varying times. He concluded 
that at the temperatures used the potatoes were killed in less time than 
was required to destroy the mosaic virus. In 1923 Schitikova 28 reported 
that dry heat at 60° C. to 66° C. for 24 to 48 hours and 85° for 30 minutes 
does not injure germination of wheat and is efficaceous against smut, but 
