The Fruit IPM Report for the week shows an upward trend with more Sharp-nosed Leafhopper (SNLH) adults maturing and moving around fields, making transmission of stunt disease to previously uninfected bushes more likely. This insect in the only regular target for post harvest sprays. Now is an appropriate time to treat.

Sharp-nosed Leafhopper Life Cycle

SNLH feeds and reproduce on blueberry, huckleberry, cranberry, and other related plants. SNLH feeding causes little direct damage but it transmits the phytoplasma that causes stunt disease in blueberries. They are small brown insects with a pointed head (Figure 1). SNLH picks up the disease while feeding on infested bushes and carries it to other plants in subsequent feedings. Usually only adults will carry the disease from plant to plant, since nymphs are wingless and can’t fly (Figure 2). This insect completes two generations in New Jersey. Adults are abundant in the woods, where many alternative hosts are present, and may move to commercial blueberry fields in the spring. Eggs overwinter inside fallen leaves and hatch in mid-May. Nymphs complete 5 instars. Nymphs from the first generation reach adult stage in mid-June, while nymphs from the second generation reach adulthood in early August. Adults move back to the woods in the fall. Monitoring these generations is critical for timing of control strategies.

Fig 1:
Sharp-nosed leafhopper adult

Fig 2: Sharp-nosed leafhopper nymph (L)
and adult (R)

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