660 
Journal of Agricultural Research 
Vol.XXXI, No 7 
Table VI. — Mean sulphate content {in terms of grams of SO 4 per liter) of tissue 
fluids of Egyptian and Upland cotton grown under irrigation at Sacaton, Ariz. y 
1922 and 1923 
Comparison of Pima Egyp¬ 
tian and Meade Upland 
cotton, 1922: 
First series, July 25 to 
Aug. 9. Comparison 
of Pima and Meade __ 
First comparison of Pima 
Egyptian and Lone Star 
Upland cotton, 1923: 
First series, July 29 to 
Aug. 14. Compari¬ 
son of Pima and Lone 
Star__ 
Second comparison of Pima 
Egyptian and Lone Star 
Upland cotton, 1923: 
Second series Aug. 18 to 
Aug. 31. Compari¬ 
son of Pima and Lone 
Star_ 
N 
Mean 
sulphate 
content for 
Egyptian 
cotton 
Mean 
sulphate 
content for 
Upland 
cotton 
Difference between Egyptian and 
Upland cotton 
Absolute 
difference 
and probable 
error 
Ratio of 
absolute 
differ¬ 
ence to 
probable 
error 
Percent¬ 
age 
differ¬ 
ence 
29 
10.5517±0. 4447 
14. 6724±0. 5385 
-4.1206±0.4189 
9.84 
28.08 
67 
12.5373± . 1022 
16.2164± .0801 
—3.6791± .1410 
26.10 
22.69 
70 
14.1642± .1294 
17.3357± . 1793 
-3.1714± . 1750 
18.12 
18.29 
SUMMARY AND CONCLUSION 
The sulphate content of the leaf-tissue fluids of Meade and Lone 
Star Upland cotton has been investigated in comparison with that of 
Pima Egyptian cotton as grown under irrigation in the Gila Kiver 
Valley, Sacaton, Ariz. 
The sulphate content of the Upland varieties (Meade and Lone 
Star) is higher than that of the Egyptian variety (Pima). The dif¬ 
ferences are clearly significant in comparison with their probable 
errors and range from 3 to 4 grams per liter, or from 18 to 28 per cent 
of the Upland value. 
These results as compared with those of the earlier study of chloride 
content show that, as far as the varieties investigated are concerned, 
the behavior of these two types of cotton with respect to the absorp¬ 
tion of chlorides and sulphates is quite different, the Egyptian type 
taking up larger quantities of chlorides, and the Upland types ab¬ 
sorbing larger quantities of sulphates. 
The relationship between the concentration of these ions in the plant, 
the relation of their concentration in the plant to that of their con¬ 
centration in the soil solution, and their behavior in inheritance are 
under investigation. 
