Agriculture: Lettuce Pest Management Guidelines

Foxglove Aphid

  • Aulacorthum solani
  • Description of the Pest

    Foxglove aphid is usually light green with dark green spots at the base of the cornicles but has several color forms, ranging from green to orange to pink. Some of the wingless aphids have many black markings on the top of the abdomen as well. The winged adults are browner than the wingless forms, but also have various black markings.

    Foxglove aphid is a pest of lettuce in California's Central Coast, although it may also occur on other crops. Winged aphids are nearly indistinguishable in the field from another pest of lettuce, the lettuce aphid. These two aphids, however, can be distinguished from green peach aphid, which has prominent, converging antennal tubercles.

    Foxglove aphid has a very short life cycle and numbers can increase rapidly. It has a wide host range.

    Damage

    Foxglove aphids feed deep inside the plant on younger leaves, but can be found scattered all over the lettuce head. It is known to vector several virus diseases including Lettuce mosaic virus.

    Management

    Monitoring and Treatment Decisions

    Monitor carefully in order to not miss early infestations that are hidden within the lettuce. This aphid has a tendency to disperse in the plant rather than forming colonies like green peach aphid. Control of foxglove aphid is difficult because of its rapid population growth combined with its preferred locations deep within the head.

    Common name Amount per acre** REI‡ PHI‡
    (Example trade name) (hours) (days)
    Not all registered pesticides are listed. The following are ranked with the pesticides having the greatest IPM value listed first—the most effective and least harmful to natural enemies, honey bees, and the environment are at the top of the table. When choosing a pesticide, consider information relating to air and water quality, resistance management, and the pesticide's properties and application timing. Always read the label of the product being used.
    A. FLUPYRADIFURONE
    (Sivanto Prime) 10.5–12 fl oz 12 1
    MODE-OF-ACTION GROUP NUMBER1: 4D
    COMMENTS: Foliar application.
    B. DINOTEFURAN
    (Venom) 6 oz 12 21
    MODE-OF-ACTION GROUP NUMBER1: 4A
    COMMENTS: Apply as a soil application at planting.
    C. IMIDACLOPRID
    (Admire Pro) 7–10.5 fl oz 12 21
    MODE-OF-ACTION GROUP NUMBER1: 4A
    COMMENTS: Apply as a soil application. Do not apply more than 0.38 lb a.i. of imidacloprid/acre per year.
    D. ACETAMIPRID
    (Assail 70WP) 0.8–1.2 oz 12 7
    MODE-OF-ACTION GROUP NUMBER1: 4A
    COMMENTS: Foliar application. Allow 7 days between applications with a maximum of 5 applications per season.
    E. PYMETROZINE
    (Fulfill) 2.75 oz 12 7
    MODE-OF-ACTION GROUP NUMBER1: 9B
    F. FLONICAMID
    (Beleaf 50SG) 2–2.8 oz 12 0
    MODE-OF-ACTION GROUP NUMBER1: 9C
    G. SPIROTETRAMAT
    (Movento) 4–5 fl oz 24 3
    MODE-OF-ACTION GROUP NUMBER1: 23
    H. THIAMETHOXAM
    (Actara) Label rates 12 7
    MODE-OF-ACTION GROUP NUMBER1: 4A
    I. DIMETHOATE
    (Dimethoate 400EC) 0.5 pt 48 Leaf lettuce: 14
    MODE-OF-ACTION GROUP NUMBER1: 1B
    COMMENTS: Some products only allow use on leaf lettuce; be sure to confirm on label the type of lettuce product is registered for.
    Restricted entry interval (REI) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (PHI) is the number of days from treatment to harvest. In some cases the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest.
    1 Rotate chemicals with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a group number of 1B; chemicals with a 1B group number should be alternated with chemicals that have a group number other than 1B. Mode-of-action group numbers are assigned by IRAC (Insecticide Resistance Action Committee).
    Text Updated: 04/17
    Treatment Table Updated: 04/17