Cabbage Aphid
|
Cabbage Aphid .jpg) Cabbage aphids are green gray with a white, waxy coating. They commonly occur in dense colonies, often covered with waxy droplets. They prefer to feed on the youngest leaves and flowering parts and are often found deep within the heads of cabbages or Brussels sprouts. The aphid has a simple life cycle with adult females giving birth to live offspring throughout the year in warmer climates. Both winged and wingless adults occur; the winged adults have a black thorax and lack the waxy coating. The aphid does not infest noncruciferous crops but can survive on related weed species when cole crops are not in the field. Susceptible Plants- Brassicas
Symptoms- Dense colonies of aphids cause distortion and discoloration of leaves. A severe infestation can check and kill shoot tips and young plants.
Prevention and Control- Check for cabbage aphid in the youngest, highest, and innermost leaves of young plants. After heading, check the flowering parts of broccoli and cauliflower and pull back wrapper leaves of cabbage. Also check for natural enemies. Broccoli and cauliflower crops can tolerate up to 100 aphids per plant up to heading. Once heads begin to form, cabbage aphids must be controlled even if only a few are present. Because of the overlapping growth of their leaves, cabbage crops require more careful management and have less tolerance for aphids even during the early vegetative stages; treat as soon as 1 to 2% of plants are infested with one or more aphids. After treating, recheck frequently and treat if populations reappear. Destroy crop remnants immediately after harvest and remove or control alternate hosts, including mustards and related weeds, around field borders. Infestations on Brussels sprouts can start in seedling beds, so be sure transplants are clean before taking them to the field. Removal and destruction of infested plants from the field can be effective early in the crop cycle. Biological Control- Aphid Parasites: Aphidius matricariae Pesticide Control- Bonide Insecticidal Soap
|
|
.png){kind=small}
.jpg)
