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Joumal of Agricultural Research voi. xxvra, no. 3 
The difference in the germination results obtained by the two methods is 
indicated best by a few examples. A typical sensitive sample germinated 71 
per cent and 54 per cent in two tests by the standard method; however, the 
sample contained a large per cent of live seed as indicated by germinations of 
95 and 94 per cent, respectively, by the prewetting method. On the other 
hand, a typical strong sample germinated 95 per cent by the standard method 
and 98 per cent after prewetting. Prewetting the seed not only prevents the 
molding of sensitive samples, but greatly hastens the germination of all samples 
(PL 1, A and B). Evidence of the prevalence of sensitive samples,.and of the 
effect of prewetting is shown by the results of one hundred and fourteen tests 
taken at random from the reports of the Texas Branch of the Seed Testing 
Laboratory; by the standard method the one hundred and fourteen tests aver¬ 
aged 66.9 per cent germination, by the prewetting method 87.5 per cent. Of 
these 114 tests, 93 were of typically sensitive samples. Of the remaining 21 
tests, 4 were of samples from Louisiana, 7 were separate tests of a single strong 
sample, 6 were of other strong samples, and 4 indicated samples with a large 
proportion of dead seeds. 
The effect of prewetting on the germination of the three types of samples is 
shown in Plates 1 and 2, Plate 1, A and B, show No. 483—a strong sample. 
The germination by the standard method (A) is as good as by the prewetting 
method (B), although slower. Plate 1, C and D, shows No. 446—a sensitive 
sample. -The excessive mold when germinated by the standard method (C) is 
typical of this type of sample. The vigorous clean germination after prewetting 
(D) indicates the high percentage of live seeds. In contrast to the above, the 
poor germination by both methods (A, standard method) (B, prewetting method) 
of a typical weak sample, No. 375851, is shown in Plate 2, A and B. 
HOW TO USE THE PREWETTING METHOD 
In the use of the prewetting method, the seeds are put in a glass jar with 
enough water to cover. This is shaken vigorously until the seeds appear uni¬ 
formly dark colored, indicating that all the air has been displaced from the fuzz 
and that the surfaces of the seeds are thoroughly wet. Then they are drained 
and the film of excess water blotted off (on account of the danger of causing 
dormancy because of too much water). The seeds are then put between folds of 
wet paper towels and germinated at the usual 20°-30° C. (68°-86° F.) alter¬ 
nation. It has not been possible to standardize the amount of shaking, as some 
samples are more difficult to wet than others. 
During the course of these investigations, the substratum for germinating 
cottonseed was changed from cloths to an absorbent quality of paper toweling. 
The germination has been found practically identical with either material, but 
the convenience and economy of the paper makes it very desirable. 
FIELD BEHAVIOR OF SENSITIVE SAMPLES 
Although we found that the sensitive samples contained a large proportion 
of live seed, which could be germinated by various simple methods, we were 
uncertain how to interpret to the planter of the seed the results of the germina¬ 
tion tests. It was necessary to know the behavior of sensitive samples in 
comparison with strong samples under different field conditions. Accordingly, 
we selected, for field study, six samples which had been tested in the laboratory 
under a wide range of conditions. Arrangements were made through the co¬ 
operation of the Office of Crop Acclimatization and Adaptation Investigations 
of this Bureau and of the Texas Agricultural Experiment Station, to have these 
samples planted at Lawton, Okla.; Greenville, San Antonio and College Station, 
