Disease Directory

    Lettuce Mosaic Virus

    Lettuce mosaic virus (LMV), Potyvirus

    Virus
    Leaves
    Whole Plant

    Overview

    A seed-borne virus of lettuce causing mosaic patterns, stunting, and reduced head formation. Transmitted by aphids and through infected seed.

    Symptoms

    Mosaic patterns of light and dark green on leaves. Leaf distortion and reduced size. Stunted growth. Poor head formation. Necrotic spots in some cultivars. Bolting.

    Environmental Conditions

    Variable

    Prevention

    Use virus-indexed seed (tested negative). Plant resistant varieties. Control aphid vectors. Remove weed hosts. Destroy crop residues.

    Management

    No cure. Remove infected plants. Use tested seed. Control aphids. Remove weed hosts including wild lettuce species.