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XXII.
Vegetable Insects
D. B.
Adams and D. G. Riley
Vegetables were
planted on an estimated 178,000 acres, or a 2% increase over the 1994 acreage. The
top five vegetables in terms of dollar value in 1996 were (1) onions, $54 milion, (2)
tomatoes, $44 million, (3) cabbage, $34 million, (4) watermelon, $32 million, and (5)
sweet corn, $24 million. The estimated control costs and crop damage associated with
vegetable arthropod pests totaled $28,844,000. The total value of vegetables based
on USDA estmates was approximately 22% less than the $434 million in 1995 because of price
drops, or an estimated $340 million, so losses were averaging less than 10% over all
vegetables. However, certain vegetable pests, such as thrips vectored tomato spotted
wilt virus (TSWV) in tomatoes and peppers, caused much higher losses in certain locations
in south Georgia.
Insect management in
vegetables is a very dynamic and often difficult process in Georgia because of the
diversity of crops and associated pests in the state, the long growing seasons
(particularly in the south), the constant change in pest status from season to season, the
movement of pests into and across the state, and the interaction of insect pests with
virus and other diseases. The following lists of pests by crop illustrates in part
the complexity of insect pests in vegetables. Some of the estimates of damage, for
example thrips + TSWV in tomatoes, are probably too conservative and do not reflect the
seriousness of this pest complex which has the potential to destroy 30% or more of the
tomato crop annually. Besides the existing vegetable pests that occur annually in
the State, some potential upcoming pests in Georgia vegetables include root aphids in fall
cole crops and broad mites in peppers and various other crops. Whitefly, beet
armyworm, and diamondback moth and others can display high levels of resistance to various
insecticides and therefore become serious problems when insecticide applications are made
without before-hand knowledge of the product's efficacy and side effects on the vegetable
pest and beneficial complex.
The 1996 estimated acreage planted, average yield, and average season prices for
each commercial crop in Georgia were as follows:
Crop |
Planted Acreage |
Average Yield |
Average Price Yield-Unit |
Cabbage |
9,791 |
497 boxes |
$ 6.20 |
Cantaloupe |
6,938 |
185 cartons |
7.39 |
Cucumbers |
10,147 |
379 cartons |
9.10 |
Leafy greens |
19,439 |
363 cartons |
8.20 |
Okra |
1,563 |
500 bushels |
6.00 |
Onions |
17,196 |
275 bags |
16.20 |
Peppers |
5,688 |
832 boxes |
8.20 |
Beans (snap, pole, and Lima) |
13,209 |
105 bushels |
13.80 |
Southern peas |
5,886 |
125 pounds |
10.50 |
Squash (summer) |
15,772 |
460 boxes |
9.80 |
Sweet corn |
18,919 |
385 crates |
6.70 |
Sweetpotatoes |
1,092 |
470 cartons |
8.70 |
Tomatoes |
5,729 |
1538 boxes |
6.80 |
Watermelons |
35,622 |
304 cwt |
5.20 |
|
Estimates of Losses and Control Costs |
Insect |
Cost of Control |
Damage |
Total |
Peppers
1 Pepper weevil
2 Thrips
3 Beet armyworm
4 Corn earworm
5 Tarnished plant bug
Subtotal |
$410,000
455,000
662,000
17,000
3,000
$1,547,000 |
$3,927,000
2,805,000
533,000
112,000
50,000
$7,427,000 |
$4,337,000
3,260,000
1,195,000
129,000
53,000
$8,974,000 |
Squash (Summer)
1 Aphid (virus)
2 Sweetpotato whitefly (silverleaf)
3 Cucumber beetles
4 Pickleworm
Subtotal |
$647,000
505,000
55,000
156,000
$1,363,000
|
$2,720,000
543,000
527,000
217,000
$4,007,000 |
$3,367,000
1,048,000
582,000
373,000
$5,370,000 |
Sweet corn
1 Corn earworm/fall armyworm
2 Stink bugs
Subtotal |
$2,705,000
62,000
$2,767,000
|
$1,087,000
44,000
$1,131,000
|
$3,792,000
106,000
$3,898,000
|
Leafy greens
1 Diamondback moth/
cabbage looper
2 Aphids
3 Grasshoppers
4 Silverleaf whitefly
5 Yellowmargined leaf beetle
Subtotal |
$1,155,000
350,000
82,000
17,000
6,000
$1,610,000 |
$315,000
608,000
405,000
3,000
1,000
$1,332,000 |
$1,470,000
958,000
487,000
20,000
7,000
$2,942,000 |
Southern peas
1 Cowpea curculio
2 Thrips
3 Beet armyworm
4 Stink bugs
5 Aphids
Subtotal |
$205,000
34,000
8,000
6,000
4,000
$257,000
|
$1,627,000
0
17,000
1,000
2,000
$1,647,000
|
$1,832,000
34,000
25,000
7,000
6,000
$1,904,000
|
Tomatoes
1 Thrips(+TSWV)
2 Fruitworm (corn earworm)
3 Stink bugs
4 Sweetpotato whitefly
5 Pinworm
6 Leafminer
Subtotal |
$284,000
114,000
15,000
29,000
8,000
26,000
$479,000
|
$891,000
95,000
105,000
89,000
55,000
24,000
$1,259,000 |
$1,175,000
209,000
120,000
118,000
63,000
50,000
$1,735,000
|
Cabbage
1 Diamondback moth/loopers
2 Silverleaf whitefly
3 Seedcorn maggot
4 Aphids
Subtotal |
$705,000
12,000
14,000
6,000
$737,000
|
$392,000
45,000
39,000
10,000
$486,000
|
$1,097,000
57,000
53,000
16,000
$1,223,000
|
Watermelon
1 Cucumber beetles
2 Aphids
3 Rindworms
(corn earworm/loopers)
Subtotal |
$481,000
68,000
35,000
$584,000
|
$169,000
79,000
12,000
$260,000
|
$650,000
147,000
47,000
$844,000
|
Snap beans
1 Thrips
2 Corn earworm
3 Stink bugs
Subtotal |
$296,000
99,000
39,000
$434,000
|
$43,000
51,000
50,000
$144,000
|
$339,000
150,000
89,000
$578,000
|
Cucumber
1 Pickleworm
2 Cucumber beetles
Subtotal |
$137,000
134,000
$271,000
|
$104,000
47,000
$151,000
|
$241,000
181,000
$422,000
|
Sweet potatoes
1 Soil insects
2 Beet armyworm/soybean looper
Subtotal |
$63,000
3,000
$66,000
|
$239,000
13,000
$252,000
|
$302,000
16,000
$318,000
|
Onions
1 Seedcorn maggot
2 Thrips
Subtotal |
$184,000
66,000
$250,000
|
$38,000
16,000
$54,000
|
$222,000
82,000
$304,000
|
Cantaloupe
1 Cucumber beetles
2 Pickleworm
Subtotal |
$83,000
14,000
$97,000
|
$119,000
1,000
$120,000
|
$202,000
15,000
$217,000
|
Okra
1 Stink bugs
2 Corn earworm
Subtotal |
$12,000
15,000
$27,000
|
$72,000
16,000
$88,000
|
$84,000
31,000
$115,000
|
Grand Total |
$10,486,000 |
$18,358,00 |
$28,844,000 |
|
| Information Pertaining to Control of Major Vegetable
Insect Pests in Georgia in 1996 |
Insect |
No. Acres Needing Control |
No. Acres Treated |
No. of Unit Applic. |
Avg. Cost Per Units Treated1 |
Yield Loss on Units Treated2 |
Yield Loss on Units Untreated2 |
Peppers
Pepper weevil
Thrips
Beet armyworm
Corn earworm
Tarnished plant bug |
4,000
6,000
5,000
0
0
|
5,000
6,000
6,000
1,000
0
|
8.0
8.0
8.0
2.0
1.0
|
$10.00
10.00
15.00
10.00
10.00
|
478,000
341,000
65,000
14,000
3,000
|
0
0
0
0
3,000
|
Squash (Summer)
Aphid (virus)
Sweetpotato whitefly (silverleaf)
Cucumber beetles
Pickleworm |
10,000
10,000
3,000
5,000
|
13,000
10,000
6,000
5,000
|
5.0
5.0
1.0
3.0
|
$10.00
10.00
10.00
10.00
|
135,000
22,000
5,000
10,000
|
174,000
39,000
54,000
15,000
|
Sweet corn
Corn earworm/fall armyworm
Stink bugs |
18,000
4,000
|
18,000
6,000
|
15.0
1.0
|
$10.00
10.00
|
162,000
5,000
|
0
1,000
|
Leafy greens
Diamondback moth/
cabbage looper
Aphids
Grasshoppers
Silverleaf whitefly
Yellowmargined leaf beetle
False chinch bug/stink bugs |
19,000
7,000
3,000
0
0
0
|
19,000
9,000
3,000
1,000
1,000
0
|
6.0
4.0
3.0
1.5
1.0
1.0
|
$10.00
10.00
10.00
10.00
10.00
10.00
|
35,000
74,000
49,000
0
0
0
|
4,000
0
0
0
0
0 |
Southern peas
Cowpea curculio
Thrips
Beet armyworm
Stink bugs
Aphids |
4,000
1,000
0
0
0
|
4,000
2,000
0
1,000
0
|
5.0
2.0
2.0
1.0
1.5
|
$10.00
10.00
10.00
10.00
10.00
|
128,000
0
1,000
0
0
|
27,000
0
1,000
0
0
|
Tomatoes
Thrips(+TSWV)
Fruitworm (corn earworm)
Stink bugs
Sweetpotato whitefly
Pinworm
Leafminer |
6,000
5,000
2,000
1,000
0
1,000
|
6,000
6,000
3,000
1,000
1,000
2,000
|
5.0
2.0
1.0
3.0
1.5
1.5
|
$10.00
10.00
5.50
10.00
10.00
10.00
|
131,000
14,000
2,000
13,000
6,000
3,000
|
0
0
13,000
0
2,000
0
|
Cabbage
Diamondback moth/loopers
Silverleaf whitefly
Seedcorn maggot
Aphids |
8,000
0
0
0
|
9,000
1,000
2,000
0
|
8.0
1.0
1.0
1.5
|
$10.00
20.00
8.00
10.00
|
39,000
2,000
1,000
0
|
24,000
5,000
5,000
1,000
|
Watermelon
Cucumber beetles
Aphids
Rindworms (corn earworm/loopers) |
21,000
2,000
2,000
|
32,000
7,000
3,000
|
1.5
1.0
1.0
|
$10.00
10.00
10.00
|
32,000
4,000
1,000
|
0
11,000
1,000
|
Snap beans
Thrips
Corn earworm
Stink bugs |
11,000
2,000
3,000
|
12,000
10,000
5,000
|
2.5
1.0
1.0
|
$9.50
10.00
8.50
|
3,000
4,000
3,000
|
0
0
0
|
Cucumber
Pickleworm
Cucumber beetles |
5,000
8,000
|
5,000
9,000
|
3.0
1.5
|
$10.00
10.00
|
2,000
3,000
|
10,000
2,000
|
Sweet potatoes
Soil insects
Beet armyworm/soybean looper |
1,000
0
|
1,000
0
|
2.0
1.0
|
$30.00
10.00
|
25,000
2,000
|
3,000
0
|
Onions
Seedcorn maggot
Thrips |
1,000
0
|
8,000
6,000
|
2.0
1.5
|
$12.00
8.00
|
1,000
1,000
|
1,000
0
|
Cantaloupe
Cucumber beetles
Pickleworm |
6,000
0
|
6,000
0
|
1.5
3.0
|
$10.00
10.00
|
10,000
0
|
6,000
0
|
Okra
Stink bugs
Corn earworm |
1,000
0
|
1,000
1,000
|
1.5
2.0
|
$8.00
10.00
|
11,000
2,000
|
1,000
0
|
|
|
1 Includes application costs.
2 See Note 1 for specific yield units. |
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