26 BULLETIN 1383, U. S. DEPARTMENT OF AGRICULTURE 
treatments to determine the possibility of using the commercial 
grain drier in connection with the steam treatment of grain, followed 
by drying the grain with warm air. 
Single-bath hot-water treatments were applied by immersing 
wheat in half-filled sacks in water held at a constant temperature 
during definite periods, the duration of treatment extending from 30 
minutes to 4 hours and the temperatures from 46° to 51° C. 
A number of the single-bath treatments completely controlled 
loose smut and effectively controlled bunt, but the treatments at 
48° C. for 1 hour and 50 minutes and at 49° C. for 1 hour and 35 
minutes gave the best results. Although the resulting germination 
was somewhat poorer than that of the untreated seeds, these treat- 
ments did not seriously reduce or retard germination, and they 
reduced yield less and required a shorter period of application than 
any of the other treatments which approximated them in general 
effectiveness. 
Wheat treated at 48° C. for 1 hour and 50 minutes or at 49° C. 
for 1 hour and 35 minutes in comparison with untreated seed showed 
poorer germination, the seedlings emerged more slowly, the plants 
yielded slightly less, and the yield was more adversely affected by 
unfavorable soil conditions. 
Wheat treated at 48° C. for 1 hour and 50 minutes or at 49° for 
1 hour and 35 minutes, in comparison with wheat treated by the 
modified hot-water method invariably germinated better, the seed- 
lings emerged more rapidly, the plants yielded considerably more, 
and the yield was not so adversely affected by unfavorable soil con- 
ditions. In general, therefore, these single-bath treatments pro- 
duced notably better results than the modified treatment. 
As in the case of the modified method, the effects of the single- 
bath method on germination were dependent on the physical condi- 
tion of the seed coats. Hand-threshed seed with unbroken coats 
suffered some retardation, but little, if any, reduction in germination. 
When the coats of hand-threshed seed were broken at definite loca- 
tions over the endosperm the treatment reduced germination con- 
siderably, and when the coats were broken over the embryo the treat- 
ment reduced germination very markedly- The germination of 
wheat with coats broken over the embryo or endosperm was reduced 
less by the single-bath method, however, than by the modified 
method. 
When the seeding rate of treated seed was increased so that the 
quantity of viable seed sown was the same as that of untreated 
wheat, plants from the latter outyi elded plants from treated seed. 
The results seem to indicate that the injurious effects of hot-water 
treatments, especially the modified treatment, are not confined to 
germination, but may extend into later stages of plant growth. 
There were no appreciable differences in the bushel weight of 
wheat grown from untreated seed and from seed treated with hot 
water by the modified or the single-bath method. 
With a simplifying of the application of single-bath hot-water 
treatments in view, experiments were conducted to determine whether 
agitation of the hot water could be substituted for agitation of the 
sacks in the water. When cotton and burlap sacks half filled with 
wheat and tied at the top were placed on slatted shelves suspended 
in mechanically agitated water at 48° C, the period required for the 
