Thrips and INSV Management in Desert Lettuce

Abstract

Thrips and Impatiens Necrotic Spot Virus (INSV) have become a major threat to desert lettuce production, particularly since 2021 with the arrival of INSV-infected transplants from Salinas. Western flower thrips (WFT) transmit INSV through a two-stage infection process: primary infection by incoming viruliferous adults and secondary spread via larvae that acquire the virus in the field. This guide outlines key recommendations for preventing INSV outbreaks, including season-long sanitation, early and aggressive insecticide applications in high-risk areas, and strategic insecticide rotations. The goal is to disrupt the thrips lifecycle and reduce virus transmission potential in desert cropping systems.