EFFKCT OF CLIMATIC CONDITIONS. 17 



K\i'\\ tliouuli llic columns in hotli T;il)los I mid II arc arran^'cd in 

 tlio order of the loss in vitality as shown l)y the aveni»^os of the 

 various places, it will at once be seen that the relative deoroeof injury 

 did not remain the same throuofhout the experiment. This is prol)al)ly 

 best explained by a variation in the climatic influences. It is evident 

 that in some of the places ^vherc seeds were stoi-ed the effects were 

 moi-e deleterious during- the time between the first and second tests 

 than they were durin«^- the first period of storaj^e of 12S days. The 

 results given in Table II are of the greater value in showing the 

 relative merits of the different localities as places for storing seeds, 

 extending as they do over a longer period of time. 



As a result of the second series of tests it was found that the average 

 percentage of germination of all of the samples of seed that were, 

 stored in trade conditions at Mobile for 202 days Avas onl}' 24.81 per cent. 

 This is equivalent to a loss in vitality of 71.98 per cent as compared 

 with the average percentage of germination of the control samples, the 

 average germination of the controls ])eing 86.77 per cent. The pansy, 

 phlox, onion, and beans stored at Mobile wholly lost their power of 

 o-ermination. The tomato seed, which proved to be the most resistant 

 to unfavorable conditions, gave a germination of 75). 5 per cent, or a 

 loss in vitalit}^ of 18.1:6 per cent, as compared with the control sample, 

 which germinated 97.5 per cent. The degree of deterioration in the 

 seeds stored at the other places was much less marked than for those 

 stored at Mobile. The loss in vitality was only 41.89 per cent in the 

 seeds returned from Baton Rouge. The results from the seeds which 

 were stored at Durham. AulKirn, Lake City, Wagoner, and San Juan 

 differed l)ut little from ihose from Baton Rouge. The relative losses 

 in vitality are in the order given. The seeds kept in the packages 

 which were stored under trade conditions in the laboratory at the 

 [Jniversity of Michigan showed a loss in vitality of only 2.52 per cent 

 as compared with the control, the seeds of which were stored in a cool, 

 dry closet on the fourth floor of the botanical lal3orator3\ Ordinarily 

 a loss of 2.52 per cent would be considered as a normal variation due 

 to sampling and testing, and such was probal)ly true in these two sets, 

 with the exception of the greater deterioration of the phlox, pansy, 

 and "B" sweet corn, which were undoubtedly injured by the unfa- 

 vorable trade conditions, as repeated tests have shown. 



From Table II it will also be seen that the "A" sweet corn, peas, 

 tomato, and watermelon, with the exception of those returned from 

 Mobile, sliow a fair percentage of germination. In some cases the final 

 percentages of germination were even higher than the controls; ])ut, as 

 previously stated, the final germination is not alwaj'S a good criterion 

 for the determination of vitality, it being necessary to consider the 

 germinative energy as a basis for comparison. In order to show this 

 more fully some of the detailed results are herewith given in Tal)le III. 

 These results show to a good advantage the degree to which germina- 

 tion has been retarded. 



25037— No. 58—04 2 



