Evaluation of Application Methods for the Chemical Control of Striped Cucumber Beetle (Coleoptera: Chrysomelidae) Attacking Seedling Cucurbits

ABSTRACT

Bioassays of treated field-aged leaves were conducted in 1998 and 1999 to determine the efficacy of various chemicals for control of striped cucumber beetle (SCR), Acalymma vittatum. In 1998, imidacloprid (GAUCHO® 480F) as a seed treatment was evaluated on cucumber (Cucunus sativis), cv. Pioneer, and squash (Cucurbita maxima), cv. Mini Green Hubbard. Three rates, 1.0 mg, 5.0 mg and 10.0 mg a.i./seed were evaluated for squash and one rate, 1.0 mg a.i./seed, for cucumber. Cucumber seeds treated with GAUCHO at rates higher than 1.0 mg a.i./seed did not germinate in this trial. All treatments protected growing cucumber and squash seedlings from SCB feeding. In 1999, the study was expanded to include foliar, seed, and planting water treatments. A single foliar application of endosulfan (THIODAN® 4EC), azinphosmethyl (SNIPER® 50WP), cypermethrin (RIPCORD® 400 EC) or imidacloprid (ADMIRE® 240F) applied to both cucumber cv. Calypso and pumpkin (Cucurbita pepo), cv. Howden, did not adequately protect rapidly growing seedlings from SCB. GAUCHO® 480F applied to cucumber, cv. Calypso, as a seed treatment at 0.75 mg and 1.0 nig a.i./seed effectively protected seedlings. Imidacloprid (ADMIRE® 240F) applied to squash transplants, cv. New England Blue Hubbard, in the starter solution at 15.0 and 25.0 ml/1000 plugs protected seedlings in the Held. Imidacloprid as both a seed and a planting water treatment provided systemic protection of developing cucurbits from adult SCB.

KEYWORDS:

• Cucurbits
• striped cucumber beetle
• control
• imidacloprid