STERILITY OF OATS. 
pension retarded growth more than the sterile water. In a number 
of cases the panicles did not push out of the sheaths, remaining un- 
developed inside, and were so moldy that it was practically impos- 
sible to make counts. How much the mold had to do in retarding 
development could not be determined. Counts from these panicles 
are given where possible. 
Table IV. — Relation of halo blight and stripe organisms to sterility in oats, as shown 
by inoculation experiments tciih Wisconsin Pedigree 5 (Swedish StUct) at Madison, 
Wis., June 25, 1920. 
[The extreme and average percentages of sterility are shown in boldface figures.] 
Normal and sterile spikelets in treated and untreated panicl 
es. Inoculum in sheaths. 
Untreated, 
bundle 1. 
Sterile water. 
Halo-blight organism. 
Stripe or- 
Panicle. 
Bundle 2. 
Bundle 3. 
Bundle 4. 
Bundle 5. 
bundle 6. 
3 
o 
3 
i 
c 
Ster- 
ile. 
3 
o 
3 
g 
o 
Ster- 
ile. 
3 
o 
3 
g 
o 
Ster- 
ile. 
3 
o 
En 
3 
g 

Ster- 
ile. 
3 

3 

Ster- 
ile. 
3 

£h 
3 
g 

Ster- 
ile. 
33 
1 
© 
Si 
a 
PL, 
,P 
Pi 
© 
© 
Pm 
2 : H 
rO ! © 
£ IPh 
2 ta 
g Is 
£ jPH 
© 
© 
© 
p-i 
© 
JO 
-A 
1 
Ph 
No.l 
52 
38 
14 
•m 
22 
30 
37 
25 
33 
21 
39 
25 
23 
24 
21 
23 
37 
28 
26 
19 
30 
12 
in 
45 
31 
34 
20 
26 
20 
11 
30 
18 
13 
9 
16 
8 
3 
16 
13 
11 
7 
9 
8 
9 
16 
9 
7 
14 
16 
13 41 
21 61 
11 55 
10i 50 
12 60 
8 : 72 
14 46 
9 40 
17 60 
12 63 
18 66 
13 61 
14j 60 
121 42 
16 j 64 
8 53 
17 
16 
10 
10 

71 41 
in 
5 
No. 2 
64 51 
58 46 
471 26 
531 44 
50! 38 
36' 24 
25; 21 
43 41 
44j 32 
41 28 
58 51 
13; 20 
12; 20 
21 44 
9 16 
12 21 
12 33 
4 16 
2 4 
12 27 
13 21 
7 12 
18 12, 40 
23 14 37 
13 12 48 
6 37 ( 27 
. . . IOO! 12 
18 
9 
31 
8 
33 
53 
'29 
"43 
46 

100 
No. 3 
11 1 
14j 7 
13! # 15 
12 17 58 
No. 4 
50; 21 
55! 28 
42i 19 
100... 
100 21 
54 21 
52 32 
0' inn 
No.5 
18 
15 
25 
11 
12 
13 
12 
16 
26 
19 
10 
15 
13 
15 
6 
14 
14 
11 
11 
45 
27 
35 
20 
28 
"22 
19 
23 
9 
16 

11 
12 
31 12 
30 16 
?7 
No. 6 
11 8 42 
34 
No. 7 
0... 
13; 8 
10 11 
17 15 
100 
3s 
52 
46 
5 
No. 8 
56 22 

No. 9 
47 
4 _ ! 
28 
19 
27 
21 
23 
28 
25 
15 
24 
29 
20 
24 
33 
33 
26 
22 
24 
10 
9 
11 

4 
8 
12 
10 
12 
No. 10 
No. 11 
9 42 
52 
166 
No. 12 
7 
11 
9 
16 
5 
17 
30 
29 
32 
61 
21 
56 
No. 13 
No. 14 
No. 15 
' 
8 
No. 16 
No. 17 
10 
13 
41 
44 
50 
5S 
45 
4S 
50 
36 
50 
No. 18 i... 
1 
No. 19 
10| 10 
10! 14 
18 15 
No. 20 
------ 

No.21 
No. 22 
' ' 
17 
13 
14 
12 
16 
13 
8 
12 
No. 23 
...1... 
No. 24 
l 
. 1 
No. 25 
1 

Average 
47 36 
10 21 
27 15 
11 
40 24 
11 
12 
52 
65 
i... 
44 
63 
j 
GENERAL SUMMARY. 
Considerable sterility occurs on oat panicles without any apparen 
connection with halo blight and in fields where there are no bacterial 
lesions. The amount seems to vary with different varieties of oats, 
some showing more sterility than others during the same season under 
similar conditions. 
The amount of sterility does not appear to be in proportion to 
susceptibility to halo blight. Wisconsin Pedigree No. 14 oats is the 
most susceptible to halo blight of the 11 varieties tested, but does not 
