Advances in Control of Onion Thrips (Thysanoptera: Thripidae) in Cabbage

Abstract

Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), feeding injury results in discoloration and a rough texture on cabbage, Brassica oleracea capitata (L.), leaves, and damage may occur deep inside the head. It has become a key pest of cabbage in the United States and many other countries. Previous studies have indicated poor control using insecticides. The present study identified imidacloprid drenches and sprays of acetamiprid, dimethoate, spinosad, and imidacloprid as insecticides that performed better than the industry standard, lambda-cyhalothrin. However, additional tests with foliar sprays of dimethoate and acetamiprid indicated there was not an ideal crop stage (precupping, cupping, or postcupping) at which either insecticide could be applied for reliable control of T. tabaci, possibly because of multiple flights of thrips into the crop or the asynchrony of flights and susceptible crop stages. In tests in a commercial field, a soil drench of imidacloprid 4 wk after transplanting reduced the number of damaged leaves in the head by 32%, whereas five sprays of acetamiprid reduced damage by 51%. Combining both insecticide regimes reduced damage by 85%, but resulted in a very costly management program. Cabbage varieties varied considerably in susceptibility with some having negligible thrips injury, regardless of being treated with an insecticide. Planting date affected susceptibility of cabbage to some degree, but not as much as other tactics. Overall, these studies indicate that increased emphasis should be placed on breeding cabbages to be resistant to T. tabaci as the foundation for its management.

Cover Crop Mulch and Weed Management Influence Arthropod Communities in Strip-Tilled Cabbage

“…An oligophagous cabbage pest, Phyllotreta cruciferae (Goeze) (Coleoptera: Chrysomelidae) and two generalist herbivores, the cabbage looper, Trichoplusia ni (Hü bner) (Lepidoptera: Noctuidae), and onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), are also of economic importance throughout the United States (Hines and Hutchison 2001, Shelton et al 2008). Specialized natural enemies, such as the parasitic wasps Cotesia rubecula (Marshall) Habitat management techniques, such as ßowering strips (PÞffner et al 2009) and companion plants (Hooks and Johnson 2003) have been studied to enhance biological control of cabbage pests and populations of these natural enemies.…”

Potential New Insecticides for the Control of Western Flower Thrips (Thysanoptera: Thripidae) on Sweet Pepper, Tomato, and Lettuce

“…Thiamethoxam and acetamiprid are group 4A chemicals commonly known as second generation neonicotinoids that affect the nicotinic acetylcholine receptor in the insectÕs nervous system (IRAC 2007). The neonicotinoids represent a major new class of insecticides for the control of thrips and other sucking insects (Horowitz et al 2004, Shelton et al 2008). Acetamiprid has contact, translaminar, and systemic activity, whereas thiamethoxam has systemic activity and long residual activity in several plants (McLeod et al 2002).…”

Evaluation of different insecticides for the management of onion thrips (Thrips tabaci Lindeman, 1889) (Thysanoptera, Thripidae) on onion (Allium cepa L.) crops

“…reduced the Thrips tabaci Lind., population for more than 2 weeks. In contrast, SHELTON et al (2008) showed that acetamiprid, dimethioate, spinosad and imidacloprid performed better than lambda-cyhalothrin against thrips on cabbage. ULLAH et al (2010) sprayed Thiodan, Confidor, Tracer, Megamos and Actara for the control of thrips on onion crops.…”