 |
 |
|
|
Approximate number of hours of wetting required for conidial infection by the leaf spot fungus at different air temperatures (a)
| Wetting Period (hr) (b) |
Average temperature |
|
Light infection |
Moderate infection |
Heavy infection |
| |
|
|
|
|
| (F) |
(C) |
|
|
|
| 81 |
27.2 |
28 |
43 |
- |
| 80 |
26.7 |
21 |
35 |
- |
| 79 |
26.1 |
18 |
30 |
- |
| 78 |
25.5 |
16 |
27 |
42 |
| 77 |
25.0 |
14 |
24 |
36 |
| 76 |
24.4 |
12 |
21 |
32 |
| 75 |
23.8 |
11 |
19 |
29 |
| 74 |
23.3 |
9 |
18 |
27 |
| 73 |
22.7 |
8 |
16 |
25 |
| 72 |
22.2 |
7 |
15 |
23 |
| 71 |
21.6 |
7 |
14 |
22 |
| 70 |
21.1 |
6 |
13 |
21 |
| 69 |
20.5 |
6 |
13 |
20 |
| 63 - 68 |
17.2 - 20.0 |
5 |
12 |
19 |
| 62 |
16.6 |
6 |
12 |
19 |
| 61 |
16.1 |
6 |
13 |
20 |
| 60 |
15.5 |
7 |
13 |
20 |
| 59 |
15.0 |
7 |
14 |
21 |
| 58 |
14.4 |
8 |
15 |
22 |
| 57 |
13.8 |
9 |
16 |
23 |
| 56 |
13.3 |
10 |
17 |
24 |
| 55 |
12.7 |
11 |
18 |
25 |
| 54 |
12.2 |
12 |
19 |
27 |
| 53 |
11.6 |
14 |
21 |
29 |
| 52 |
11.1 |
15 |
23 |
31 |
| 51 |
10.5 |
17 |
25 |
33 |
| 50 |
10.0 |
19 |
27 |
35 |
| 49 |
9.4 |
20 |
29 |
38 |
| 48 |
8.8 |
23 |
32 |
42 |
| 47 |
8.3 |
25 |
34 |
46 |
| 46 |
7.7 |
28 |
38 |
51 |
(a) Adapted from Eisensmith and Jones, 1981. Plant Dis. 65:955-958 and Phytopathology 71:728-732.
(b) The infection period is considered to start when rain begins.
Please send any comments or suggestions
regarding this site to:
Bill Klein, kleinw@msu.edu
Last Revised: 3-5-99
|
|
|
|
|