EFFICACY OF THREE OMRI LISTED MATERIALS, ALONE AND IN COMBINATION, FOR CONTROL OF STRIPED CUCUMBER BEETLE IN CUCUMBER, 2009

Three Organic Materials Review Institute (OMRI) listed foliar treatments for control of striped cucumber beetle in cucumbers were compared at the University of Massachusetts Crops Research and Education Center in South Deerfield, MA. Each material was tested alone and in combination with the other materials. Treatments included spinosad (Entrust 80W), pyrethin (PyGanic EC 5.0), and kaolin clay (Surround WP). Control plots were treated with water. Untreated seeds of 'Marketmore' pickling cucumber were planted in a heated greenhouse on 29 Apr 2009 and transplanted into the field on 27 May using a RCB design with 8 treatments and 4 replicates. Each treatment plot consisted of a 1.22m bed of two rows, 0.46m apart and 4.57m long, separated from other plots by 1.83m. Beds were covered in black plastic with one run of drip irrigation centered between the rows. Treatments were applied on 1, 8, and 15 Jun, using a CO2 R&D backpack sprayer with a flat fan nozzle delivering 19.2 gpa water at 40 psi. On 3, 10, and 17 Jun, five plants were randomly selected from each row of each plot and sampled for number of live SCB present, number of dead SCB, feeding damage to cotyledons, and feeding damage to true leaves. Feeding damage was rated as a percentage of total leaf surface defoliated, on a scale of 0-5: 0 (no damage), 0.5 (1-10% defoliation), 1 (11-20%), 2 (21-40%), 3 (41-60%), 4 (61-80%) or 5 (over 80 %). Data were averaged over sampling dates and analyzed with ANOVA; means separation used Tukeys, P=0.05.