Cabbage aphid (Brevicoryne brassicae)
Turnip aphid (Lipaphis pseudobrassicae)
Green peach aphid (Myzus persicae)
During summer the life cycle of the cabbage-infesting aphids is similar to that of other aphids. Female aphids give live birth to daughter aphids and no sexual reproduction occurs. Aphids may mature in less than two weeks under summer temperatures and can produce several young daily for a period of a couple of weeks. In the absence of natural controls aphid populations increase rapidly.
Cabbage aphids and turnip aphids solely develop on mustard family plants. Winter is spent on winter annual mustard weeds or surviving crop debris of cole crops. Green peach aphid has a much wider range of summer hosts and is important on several vegetable crops, including pepper, potato, and lettuce. Green peach aphid host alternates during the cool season months and winters as an egg stage on various stone fruits, such as peach, apricot, and certain plums.
The three cabbage-infesting aphids can be distinguished, in part, by the way covering on the insect. Cabbage aphid is blue-gray and covered with fine wax particles. Wax also covers the body of the turnip aphid, which ranges in shades of brown. Green peach aphid does not have the powdery wax cover, is smooth bodied and is often straw colored.
Cabbage aphid feeding on expanding leaves causes twisting and discoloration. Aphids can also be serious contaminant of marketed heads and is very commonly damaging to Brussels sprouts.
Turnip aphid and green peach aphid are much less damaging to growth of cole crops. Problems with these species sometimes occur with contamination of produce.
Natural Controls
Aphids can be heavily attacked by several natural enemies. Parasitic wasps are perhaps the most conspicuous of these, causing aphids to swell and stick to plants when dead, a form known as an 'aphid mummy'. General predators include larvae of syrphid (flower) flies, damsel bugs, and minute pirate bugs. Green lacewing larvae and lady beetles also feed on aphids, although cabbage aphid is not a preferred host.
Cultural Control
Overwintering crop debris of cole crops should be destroyed to eliminate cabbage aphid winter hosts.
Chemical Control
Plant coverage is critical to aphid control since aphids can locate in folds of developing leaves. Insecticides with systemic activity can improve coverage and provide better control. On Brussels sprouts applications made as sprouts begin to form will be more effective than applications made after aphids have migrated underneath leaves.
Almost all insecticides used on cole crops suggest use of wetting agents to improve coverage due to the waxy leaves
Product List for Aphids on Cabbage, Cauliflower, Broccoli and Brussels sprouts:
Insecticide |
Product (Fl oz. or oz. product per acre) |
Preharvest Interval, remarks |
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Planting Time Treatments |
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Admire 2F |
10-24 fl. oz./A |
12 hour reentry. Planting time treatment or transplant drench. Neonicotinoid insecticide (imidacloprid) with systemic activity
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Foliar Applications |
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Fulfill |
2.75 oz./A |
7 day PHI, 12 hour reentry. Selective insecticide (pyrmetrozine) with minimal impact on natural enemies of aphids. |
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Provado 1.6F |
3.75 fl. oz./A |
7 day PHI, 12 hour reentry. Neonicotinoid insecticide (imidacloprid) with systemic activity |
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Assail 70WP |
0.8-1.2 oz./A |
7 day PHI, 12 hour reentry. Has systemic activity. Neonicotinoid insecticide (acetamiprid) |
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dimethoate |
several formulations |
7 day PHI, 48 hour reentry. Organophosphate insecticide (dimethoate) with systemic activity. Registered use on cauliflower, broccoli and cabbage. |
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Fulfill 50WDG |
2.75 oz |
7 day PHI, 12 hour reentry. A specific aphicide (pymetrozine) |
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Orthene 75S |
2/3-1 1/3 lbs./A |
14 day PHI, 24 hour reentry. Organophosphate insecticide (acephate) with systemic activity. Registered use on cauliflower and Brussels sprouts only. |
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endosulfan (Phaser, Thiodan, Thionex, etc.) |
as labelled |
7 day PHI for cabbage and broccoli; 14 day PHI for cauliflower and Brussels sprouts. 24 hour reentry. Chlorinated hydrocarbon insecticide (endosulfan) |
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Danitol |
10 2/3-16 fl. oz./A |
7 day PHI, 24 hour reentry. For aphid control designed to be used with Orthene. Pyrethroid insecticide (fenpropathrin) with some aphid activity. Restricted Use because of extreme toxicity to aquatic organisms. |
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Warrior |
2.56-3.84 fl. oz./A |
1 day PHI, 24 hour reentry. Pyrethroid insecticide (lambda-cyhalothrin). Restricted Use because of extreme toxicity to aquatic organisms. |
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Capture 2E |
2.1-6.4 fl. oz./A |
7 day PHI, 24 hour reentry. Pyrethroid insecticide (bifenthrin). Restricted Use because of extreme toxicity to aquatic organisms. |
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RRestricted use pesticide 1 Labeled for chemigation 2 Generic active ingredient, several formulations |
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The information herein is supplied with the understanding that no discrimination is intended and that listing of commercial products, necessary to this guide, implies no endorsement by the authors or the Extension Services of Nebraska, Colorado, Wyoming or Montana. Criticism of products or equipment not listed is neither implied nor intended. Due to constantly changing labels, laws and regulations, the Extension Services can assume no liability for the suggested use of chemicals contained herein. Pesticides must be applied legally complying with all label directions and precautions on the pesticide container and any supplemental labeling and rules of state and federal pesticide regulatory agencies. State rules and regulations and special pesticide use allowances may vary from state to state: contact your State Department of Agriculture for the rules, regulations and allowances applicable in your state and locality. |
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Categories: Cole Crops, Heading Brassicas, Insects, Aphids
Date: 01/19/2004