Feb. 9 ,1924 Effect of Fertilizers on Stem Rust of Wheat 355 
Table V.— The effect of commercial and natural fertilizers on the percentages of stem 
rust and leaf rust , and the total number of days for maturity for Haynes Bluestem and 
the resistant hybrid in 1915 on University Farm , St. Paul, Minn. 
Infection and growing period. 
Fertilizer, kind and amount per acre. 
50 tons of manure per acre, plus— 
j 
i 
1 
1 
None. 
Noth¬ 
ing. 
Sodium 
nitrate, 
500 
pounds. 
Acid 
phos¬ 
phate, 
1,000 
pounds. 
Potas¬ 
sium 
chlorid, 
1,000 
pounds. 
CABBAGE SOIL 
Percentage of stem rust, Haynes Bluestem.... 
Percentage of stem rust, hybrid. 
Percentage of leaf rust, Haynes Bluestem. 
Percentage of leaf rust, hybrid. 
Days for maturity of Haynes Bluestem. 
87 
30 
7 
27 
“5 
88 
30 
15 
27 
114 
8S 
37 
IO 
25 
114 
90 
40 
12 
30 
114 
70 
40 
15 
20 
94 
CLOVER SOIL 
Percentage of stem rust, Haynes Bluestem.... 
Percentage of stem rust, hybrid. 
Percentage of leaf rust, Haynes Bluestem. 
Percentage of leaf rust, hybrid. 
Days for maturity of Haynes Bluestem. 
85 
40 
12 
30 
“3 
80 
43 
I S 
27 
114 
86 
48 
12 
25 
114 
87 
46 
12 
20 
113 
70 
35 
20 
28 
104 
alfalfa soil 
Percentage of stem rust, Haynes Bluestem.... 
Percentage of stem rust, hybrid. 
Percentage of leaf rust, Haynes Bluestem. 
Percentage of leaf rust, hybrid. 
Days for maturity of Haynes Bluestem. 
80 
38 
25 
'37 
114 
74 
38 
30 
35 
“5 
76 
35 
25 
32 
115 
78 
3 6 
25 
35 
115 
70 
25 
35 
35 
no 
On July 1 a few uredinia of stem rust were found on Haynes Bluestem 
but not on the hybrid. On July 27 Bluestem in all plats was quite 
uniformly infected with stem rust, although the percentage of infection 
on the plants in the cabbage soil was slightly higher than that on those 
in the clover soil, and those in the clover soil were slightly more severely 
affected than those on the alfalfa soil. The cause of these differences 
lay in the fact that the plats on the cabbage soil were nearest to heavily 
rusted barberry bushes. Therefore, a comparison between the amount 
of stem rust on plants in cabbage soil and those in alfalfa and clover soils 
can only be general. The degree of rust infection in these different series 
is correlated with the proximity of the plats to the rusted barberry 
bushes. On August 6 stem rust was spreading rapidly to stems and 
leaves on Bluestem in all the plats, but the spread on the hybrid was only 
moderate. The hybrid lodged severely in all of the manured plats, while 
the Bluestem lodged moderately in a few of them. Both varieties stood 
up perfectly in all of the control plats, except one in which the hybrid 
lodged somewhat. 
