Cercospora Leaf Spot Control Research Sidney, MT
Barry J. Jacobsen, MSU-Bozeman Joyce Eckhoff and
Jerry Bergman, Cooperators
Cercospora leaf spot caused by the
fungus, Cercospora beticola, is an important sugar beet disease in the Holly Sugar
producing area. It causes losses in tonnage, sugar content and decreases extraction
efficiencies.
Table 1. 1998 Sidney Variety Performance When Treated or not Treated for
Cercospora Leafspot Control
| |
%
Sugar |
Sucrose
/ Acre |
| Variety |
Treated |
Untreated |
Treated |
Untreated |
| HH90 |
12.1 |
10.5 |
5427 |
3306 |
| HH111 |
12.9 |
11.2 |
5418 |
4264 |
| KW2262 |
13.2 |
11.6 |
5110 |
3812 |
| Monarch |
13.1 |
11.1 |
4989 |
3371 |
| Maribo 9581 |
12.9 |
10.7 |
4519 |
3067 |
| Beta Z702 |
12.7 |
10.9 |
4949 |
2476 |
| |
LSD 5 % = 0.63 |
LSD 5 % = 849 |
| Treatments initiated July 5
and performed at 14 day intervals Spray #1 -
Benlate 2 lb/A
Spray #2 - Supertin 3.75 oz/A
Spray #3 and #4 - Benlate 2 lb/A % Supertin 3.75 oz/A
Previous Crop: Sugarbeets |
Table 2. Results of
1998 Sugar beet Cercospora leaf spot fungicide control trials
| |
|
Sucrose |
|
| Treatment 1,2 |
AUDPC
3 |
lb
/ a |
%
Sugar |
| |
|
|
|
| BAS 500-00 0.15 |
51.19 |
6408 |
14.23 |
| BAS 500-00 0.20 |
21.99 |
6300 |
14.07 |
| BAS 500-00 0.25 |
16.28 |
7245 |
14.31 |
| BAS 500-01 0.15 |
20.4 |
6541 |
14.37 |
| BAS 500-00 0.15+BACJ |
35.84 |
6378 |
13.67 |
| QUADRIS 0.15 |
35.78 |
5613 |
13.96 |
| QUADRIS 0.15+BACJ |
58.58 |
5909 |
13.39 |
| TILT 4 oz |
32.07 |
5797 |
13.90 |
| TILT 4 oz +CGA 279202 7oz |
8.39 |
6760 |
13.81 |
| TILT 4 oz +BACJ |
42.71 |
5562 |
13.92 |
| SuperTin 3.75 oz |
33.58 |
6311 |
13.69 |
| BENLATE 0.50 |
9.07 |
6996 |
14.24 |
| BENLATE 0.50+BACJ |
18.57 |
6073 |
13.54 |
| EMINENT 25 ml+BACJ |
18.99 |
6101 |
14.30 |
| EMINENT 25 ml+ECHO 100 ml |
2.65 |
6651 |
14.54 |
| EMINENT 37.5+ECHO 100 ml |
3.39 |
5889 |
13.96 |
| EMINENT 50 ml+ECHO 100 ml |
3.73 |
6442 |
13.64 |
| BACJ |
87.19 |
5136 |
13.63 |
| CGA 2792002 7oz |
13.17 |
6069 |
14.38 |
| Untreated |
176.61 |
4820 |
12.93 |
| LSD 5% |
37.57 |
1356 |
0.63 |
Rate in lb/A unless other
units are listed
First application on 7/7/97 with 3
additional sprays @ 14 day intervals
Area Under the Disease Progress
Curve-disease ratings on 8/12, 8/27 and 9/25/98
A severe hailstorm defoliated these plots
on 9/2/98 |
