28 



BULLETIN 102, U. S. DEPARTMENT OF AGRICULTURE. 



to the arrival upon the market of the new crop, when practically 

 all of the corn is graded down because of its excessive moisture and 

 not because of inferior quality. 



As already stated, these investigations have shown that 22 c. c. 

 most closely approximates the maximum degree of acidity found to 

 be contained in sound or normally perfect corn. 



Table XIII shows the average percentage of sound corn, the 

 average percentage of germination, and the average degree of acidity 

 of each commercial grade. In comparison with these general aver- 

 ages there is likewise shown the relation of the amount of sound corn 

 and the percentage of germination found in samples having a degree 

 of acidity greater than 22 c. c. to the amount of sound corn and 

 the percentage of germination found in samples showing a degree of 

 acidity less than 22 c. c. 



Table XIII. — Relation of the -percentage of germination and the percentage of sound corn 

 to the degree of acidity found in samples above and below 22 c. c. acidity, by grades, for 



a year. 



Grade. I Item of comparison. 



1 



Number gound Germj . 

 samples. com - Dation ' 



Acidity. 



| 

 (General average of all samples 



21S 

 63 



Per cent. 

 90.61 

 91.20 

 90.60 



88.60 

 87.10 

 89.38 



87.72 

 81.25 

 88.15 



75.20 

 53.58 

 87.23 



Per cent. 

 44.40 

 28.23 

 51.23 



48.80 

 30.28 

 54.45 



48.60 

 25.94 

 53.57 



32.50 

 13.60 

 44.90 



C.c. 

 20.11 

 24.21 





155 



731 

 171 

 546 



962 



185 

 744 



230 

 85 

 133 



18.48 





19.63 





24.84 





18.00 



[General average of all samples 



19.64 





27.44 



[Average of samples below 22 c. c. aciditv 



17.70 





22.42 





30.47 





18.00 









Table XIV further establishes the same relationship between the 

 percentage of sound corn, the percentage of germination, and the 

 degree of acidity. In this table, which represents No. 2, No. 3, 

 No. 4, and sample-grade corn, respectively, the samples are grouped 

 by months and the amount of sound corn and the percentage of 

 germination of samples above and below 22 c. c. acidity is compared. 



This table shows that less sound corn and lower germinative 

 power were found in the samples which ranged above 22 c. c. acidity. 

 In the lower grades the decrease is more marked in both the percent- 

 age of sound corn and the percentage of germination. In the case 

 of No. 2 corn the percentage of sound corn remains quite constant 

 whether the sample showed acidity greater or less than 22 c. c, but 

 the percentage of germination decreases with the increase in degree 

 of acidity. The acid test detects deterioration of the germ where 

 the eye does not, and it discriminates against the kernels of low ger- 

 minative power. 



