Volume 9, Issue 20 August 10, 2001
Volume 9, Issue 20 August 10, 2001
Vegetables
Vegetable Insects
- Joanne
Whalen, Extension IPM Specialist; jwhalen@udel.edu
Cabbage.
Economic levels of diamondback and cabbage looper larvae can both be found in fall cabbage. A treatment is recommended when 5% of the plants are infested with larvae. If both species are present, Avaunt (3.5 oz/acre), a Bt, Proclaim (3 oz/acre), or Spintor (4-5 oz per acre) will provide control. If cabbage looper is the predominant species, a pyrethroid or Confirm (8 oz/acre) will also provide control.
Cucurbits.
Striped cucumber beetle and squash bug populations continue to be found in cucurbits. Both can cause defoliation and damage to the rinds of fruit. A treatment should be applied for cucumber beetles if populations are increasing and before rind damage occurs. A treatment should be applied for squash bugs if you find just one egg mass per plant or when nymphs are first detected. Thiodan or a pyrethroid generally provide effective cucumber beetle control; however, multiple applications may be needed. Multiple applications of the highest labeled rate of a pyrethroid are generally needed for squash bug control.
Lima Beans.
Corn earworm larvae can now be found in the earliest planted lima beans. As soon as pin pods are present, you should sample for earworm, lygus and stinkbugs. A treatment should be applied if you find one corn earworm per 6 foot of row or 15 tarnished plant bugs and/or stinkbugs per 50 sweeps. Lannate or Capture can be used to control all 3 insects on lima beans.
Peppers.
At the present time, all peppers that have fruit ½ inch in size or larger should be sprayed on a 7-10 day schedule for corn borer and pepper maggot control. A continuous pyrethroid program should not be used to avoid aphid explosions.
Snap Beans.
All processing snap beans in the bud and pins stages should be treated with Orthene for corn borer control. A third treatment with Asana, Capture or Lannate will be needed within a week of harvest. If corn borer catches increase, multiple applications will be needed between the pin spray and harvest. In addition, when corn earworm catches increase to 10 per night, a pyrethroid should be combined with Orthene at the pin spray. As soon as pin pods are present, fresh market snap beans should be sprayed on a 7-day schedule with Lannate or Capture.
Sweet Corn.
All fresh market silking sweet corn should be sprayed on a 3-4 day schedule throughout the state.
Lima Bean Irrigation- Ed Kee, Extension Vegetable Crops Specialist; kee@udel.edu
As lima beans begin to flower and set pods, remember they
can use 0.25 to 0.33 inches per day when temperatures are in the 90s. It has been demonstrated in research and in
commercial settings that keeping adequate soil moisture is important to
obtaining good yields, especially on earlier beans that may undergo more heat
stress.
Daily Price Report for Laurel Auction Market
Prices for daily
sales at the Laurel Auction Market are available at the following website:
http://www.delmarvaproduce.com
At the mainpage,
click on Daily Price Report and select the date you wish to review. The following is an example of the price
listings:
Users can sort lots
by produce type for specific produce items. Size, weight, unit price quantity,
and lot price information are also included.
Vegetable Diseases
- - Bob Mulrooney,
Extension Plant Pathologist; bobmul@udel.edu
Late Blight Update
|
Date |
Total DSV |
Spray Recommendation |
|
5/16 |
0 |
|
|
5/17 |
11 |
|
|
5/20 |
29 |
|
|
5/30 |
51 |
5-day, low rate |
|
6/3 |
57 |
5-day, low rate |
|
6/5 |
57 |
5-day, low rate |
|
6/7 |
57 |
7-day, low rate |
|
6/11 |
59 |
10-day, mid rate |
|
6/13 |
60 |
10-day, mid rate |
|
6/17 |
76 |
7-day mid rate |
|
6/20 |
76 |
7-day high rate |
|
6/24 |
88 |
7-day high rate |
|
6/27 |
88 |
7-day high rate |
|
7/1 |
89 |
10-day, high rate |
|
7/4 |
90 |
10-day, high rate |
|
7/8 |
92 |
10-day, high rate |
|
7/11 |
94 |
10-day, high rate |
|
7/15 |
94 |
10-day, high rate |
|
7/18 |
99 |
7-day, high rate |
|
7/22 |
102 |
7-day, high rate |
|
7/25 |
106 |
10-day, high rate |
|
7/30 |
116 |
5-day, mid rate |
|
8/1 |
117 |
5-day, mid rate |
|
8/6 |
120 |
7-day, high rate |
This will be the last regular late blight report for 2001. With this week’s 90°F + forecast late blight will not be an issue for Delaware growers. No one in the region reported late blight on potatoes again this season.
Vegetable Diseases - Kate
Everts, Extension Vegetable Pathologist, University of Delaware and University
of Maryland; everts@udel.edu
EFI Values (Environmental Favorability Index)
Do
not use MELCAST if there is a disease outbreak in your field, it is a preventative program. Any questions,
please call David Armentrout at (410) 742-8788 or e-mail: da88@umail.umd.edu
|
Location |
8/1 |
8/2 |
8/3 |
8/4 |
8/5 |
8/6 |
8/7 |
8/8 |
|
Bridgeville, DE |
1 |
1 |
2 |
2 |
3 |
4 |
1 |
0 |
|
Laurel, DE (Collins Farms) |
1 |
1 |
3 |
4 |
4 |
7 |
2 |
3 |
|
Galestown, MD |
1 |
1 |
3 |
2 |
2 |
6 |
2 |
2 |
|
Georgetown, DE |
1 |
1 |
3 |
3 |
4 |
4 |
2 |
1 |
|
Hebron, MD |
1 |
2 |
3 |
2 |
3 |
7 |
3 |
3 |
|
Salisbury, MD |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
Laurel, DE (Vincent Farms) |
1 |
1 |
2 |
2 |
2 |
3 |
0 |
0 |
Watermelon
Fields should be sprayed with a fungicide when 30 EFI values have been
accumulated by the weather station nearest your fields. Add 2 points for every overhead
irrigation. After a fungicide spray,
reset your counter to 0 and start over.
If a spray has NOT been applied in 14 days, apply a fungicide and reset
the counter to zero. The first and last
day above can be partial days so use the larger EFI value of this report and
other reports for any specific day
More detailed information
concerning MELCAST and sample data sheets are available on the web at http://www.agnr.umd.edu/users/vegdisease/vegdisease.htm.
. v
Field
Crops
Field Crop Insects - Joanne Whalen, Extension IPM Specialist;