Evaluating the host-plant selection of tobacco thrips (Frankliniella fusca) on peanut and cotton

Tobacco thrips, Frankliniella fusca (Thysanoptera: Thripidae), is an early-season annual pest of seedling cotton and peanut in the southeastern United States. The planting window and timing of thrips infestations into these crops overlap in the region. Current management strategies for thrips and tomato spotted wilt virus (TSWV) in peanuts rely heavily on pre-plant cultural practices and systemic insecticides applied in-furrow. ThryvOn is a relatively new cotton variety with a new Bt trait (Cry51Aa2) that protects against thrips and plant bugs. However, unlike other Bt varieties that protect against lepidopteran species, this variety is non-lethal to thrips and plant bugs but reduces egg-laying and feeding behavior. While ThryvOn effectively reduces thrips pressure in cotton, its non-lethal characteristics raise questions about thrips dispersal and host utilization, as cotton and peanuts are often grown in proximity in the Florida Panhandle and across the Southeast. This study evaluated the host preference of adult tobacco thrips in ThryvOn and non-ThryvOn cotton in greenhouse and field settings. Choice tests were conducted at three plant growth stages: seedling, two true leaves, and four true leaves. Thrips were released into experimental arenas and field plots containing all three host types, and their distribution was assessed after a standardized exposure duration. The objective was to determine whether ThryvOn cotton alters thrips host selection behavior, potentially influencing population dynamics and TSWV risk in adjacent peanut crops. These findings will provide insight into the ecological consequences of ThryvOn adoption and update integrated management strategies in peanut-cotton production landscapes.