490 
Journal of Agricultural Research 
Vol. XXVIII, No. 5 
20° C., inclusive, found that a germination test indicated no injury, but in the sub¬ 
sequent growth it became evident that the plants from the soaked seed were less 
in size and weight than an equal number of plants from untreated seed. 
Braun ( 1) by soaking wheat seed for 10 minutes in water, then draining and 
covering them for six hours, found that the efficiency of the disinfectant used was 
increased, due to the stimulation of the dormant bacteria on the seed into a grow¬ 
ing condition, in which state they are more easily destroyed and that the harmful 
effects of long continued soaking were thus largely obviated. In his general work 
on the internally borne seed disease Chen (2) used this same method to free the 
seed coats from live organisms by disinfection. 
DISTINCTION BETWEEN BLIGHT AND WILT 
# 
The disease to which this paper makes especial reference is produced by Bacte¬ 
rium flaccumfaciens Hedges and has been called bean wilt. Unfortunately the 
earlier literature makes no distinction between the bean disease caused by this 
organism which was only recently isolated and named, and the bean blight by 
Bad. phaseoli Erw. Sm. The statements in this brief review of the literature will 
apply to either or both of the diseases and the term blight will be applied to the 
disease not specifically ascribed to Bad. flaccumfaciens. As the two diseases 
mentioned are very closely allied and likely to be confused, it might be well to call 
attention to the differences between them as recently brought out by Florence 
Hedges (5, 6): 
1. The wilt organism apparently does not produce stomatal infection as does 
the blight organism and is not accompanied by conspicuous yellowing of the 
leaves. 
2. Wilt organisms resist desiccation for a much longer period (even 5 years) 
than that previously reported for Bad. phaseoli. 
3. In pod infections the wilt follows the sutures whereas Bad. phaseoli 
produces spots. 
FACTORS AFFECTING THE BEAN BLIGHT 
With the idea of disinfection Edgerton and Moreland (3) treated bean seed in¬ 
fected with the blight organism by soaking for eight minutes in water at 50° C. 
They found that this treatment not only did not affect the blight organisms 
seriously but that the plants from the seed thus treated were more affected by 
the disease than the plants from the untreated seed. This anomalous condition 
they explained was probably due to the reduction of the vitality of the seed by 
the treatment, this contributing to the susceptibility of the plants to the disease. 
It is quite possible too that the stimulation of the seed-borne organisms occasioned 
by the water was an important factor. If so small an amount as is added by the pro¬ 
cess of inoculation can produce noticeable results, the moisture which naturally 
comes in contact with the seed must have a bearing on the development of the 
disease. Sackett (12) is of the opinion that warm wet weather favors the bean 
blight and Muncie (10) making observations in Michigan found that the disease 
is more widespread under wet and muggy conditions. Rapp (11) observed 
that cool wet weather does not favor the development of the disease but found 
that it continues to spread following warm wet weather. He considers rain 
and dew important factors in the transmission of the disease. Halsted (4) corre¬ 
lated an increase in bean blight to irrigation, and Sackett (13) thinks this is one 
of the factors for disseminating the disease. 
THE RESULTS OF 1922 
Since the harvest of seed from the 1922 experiments has not been reported 
hitherto, it seems advisable to give the results here (Table I) as a corroboration 
