Overwintering of flower thrips in blueberry crops

Flower thrips (Thysanoptera: Thripidae) pose a significant threat to blueberries, causing feeding injuries, degrading fruit quality, and transmitting viral diseases. In the southern United States, flower thrips undergo a slow winter development, while in northern regions, they overwinter as pupae beneath plant litter in the soil. As spring progresses, thrips populations surge on wild plant hosts, and with the senescence of spring flowers, agricultural fields become isolated hubs for thrips aggregation. Patches of uncultivated plants often serve as overwintering sites, and the thrips migrate into cultivated systems as spring emerges. This study investigated the overwintering biology of flower thrips in blueberry crop systems, with a focus on identifying alternative hosts and locations. Investigating overwintering sites involved the use of emergence traps and the collection of plant materials from various weed species. Preliminary results indicate that flower thrips overwinter in alternative weed hosts, including wild radish, heartwing sorrel, dandelion, and other species. Additionally, within the blueberry field, the area between rows emerges as a potential reservoir for thrips during the winter. This research offers critical insights into alternative hosts, life cycles, and seasonal dynamics, empowering growers to implement targeted interventions for effective pest management and crop protection. Understanding the overwintering behavior of flower thrips is vital for developing proactive strategies to mitigate their impact on blueberry crops.