Impact of Variety, Planting Date and At-plant Insecticide on Thrips and Tomato Spotted Wilt Virus Management in Alabama Peanuts

Peanuts grown in Alabama are at risk of thrips injury and tomato spotted wilt virus (TSWV) infection, which could result in reduced yield and seed quality at harvest. Feeding from thrips can cause severe seedling injury and potential stand loss, but the primary concern is transmission of TSWV. To control this disease, management practices such as planting date, varietal selection, and insecticides use are utilized. The objective of this experiment was to evaluate how three planting dates of varying thrips infestation risk, three varieties of varying susceptibility to TSWV, and the use of Thimet insecticide impacts thrips injury, TSWV incidence, and yield. A field study was done in 2022 and 2023 at the Wiregrass REC in Headland, AL, where the research plots were grown near other fields of row crops such as cotton, corn, soybeans, and peanuts. Treatments included three varieties (GA-06G, GA-12Y and AU-NPL 17) planted at high (April), low (May) and mid (June) TSWV risk planting dates with and without Thimet in-furrow insecticide. Overall, planting date was the driving factor for thrips injury, TSWV incidence and yield. Peanuts planted in April tended to have higher injury and TSWV with lower yields. While it did not significantly impact TSWV incidence, peanuts treated with Thimet had significantly lower injury ratings and higher yields than those not treated, when averaged across planting dates and varieties. Based on these data, peanut growers in Alabama should focus on avoiding April planting dates to reduce their risk of TSWV infection and maintain yield potential.