Feb. 9, 1924 
Resistance of Wheat to Puccinia graminis tritici 
395 
In setting up this series of cultures two liters of sand were placed in 
each crock, to which was added 1,900 cc. of distilled water containing the 
entire amount of the salts used. A constant water table was maintained 
by adding distilled water. A water gauge was inserted in the hole at 
the bottom of the crock and paraffined in to insure a ready means of 
observing the water table for each pot. In addition to the water gauge 
from the bottom of the crock, an inverted thistle tube was placed in the 
center, so that the bell of the tube, covered with cheesecloth, was 2 inches 
from the bottom. This furnished good aeration and permitted excellent 
root development. 
Two series were set up on different dates, January 29, 1922, and June 
14, 1922. Haynes Bluestem wheat, C. I. 2874, from the same seed lot, 
was sown in each series. Tables VI and VII give the salt combinations 
used. 
Table VI .—Salts used in series of sand cultures started January 2Q, IQ 22 , to determine 
the relation of nutrient salts to development of stem rust 
Series No. 
Salt. 
Grams per 
liter. 
Gram molecules 
per liter. 
fCa(NO :j )j. 
1.279 
0. 0078 
IOI. 
kh 2 po 4 . 
I. 471 
0.361 
. 0108 
MgS 0 4 . 
. 0030 
fCa(NO ;! ) 2 . 
I. 279 
. 0078 
102. 
kh 2 po 4 . 
I. 471 
. 0108 
MgS 0 4 . 
O. 361 
. 0030 
kno 3 . 
I. 729 
. 0171 
Ca(N 0 3 ) 2 . 
I. 279 
. 0078 
kh 2 po 4 . 
I. 471 
. 0108 
io 3 . 
MgS 0 4 . 
O. 361 
. 0030 
MgHP 0 4 . 
2. 982 
. 0171 
(Ca(NO.,>,. 
I. 279 
. 0078 
104. 
kh 2 po 4 . 
I. 47I 
. 0108 
MgSO,. 
0.361 
. 0030 
k 2 so 4 . 
2. 980 
. 0171 
fCa(N 0 3 )o. 
I. 279 
. 0078 
io 5 . 
kh 2 po 4 “. 
I. 47I 
. 0108 
MgS 0 4 . 
O. 361 
. 0030 
NaN 0 3 . 
I- 454 
. 0171 
(Ca(N 0 3 )o. 
i. 279 
. 0078 
106. 
kh 2 po 4 . 
I. 47I 
. 0108 
MgSO,. 
O. 361 
. 0030 
CaHP 0 4 . 
2. 943 
. 0171 
fCa(N 0 3 ) 2 . 
I. 279 
. 0078 
107. 
kh 2 po 4 . 
I. 47I 
O. 361 
. 0108 
# 
MgS 0 4 . 
. 0030 
