Evaluation of fungicides for control of downy mildew on cucumber, Kinston 2018

摘要

The experiment was conducted at the Cunningham Research Station in Kinston, NC. Plots were single raised beds on 5-ft centers covered with white plastic mulch; 14-ft long with 5-ft fallow borders on each end with non-treated guard rows on each side. The previous year the field was planted with sweetpotato. Cucumber was direct seeded on 24 Jul (2-ft in-row spacing, 2 seed/hill) and thinned to one plant per hill after emergence (7 plants/plot). Irrigation and fertilization (4-0-8, N-P-K) were applied via drip tape. Treatments were randomized into four complete blocks. Fungicide treatments were applied using a CO2-pressurized backpack sprayer equipped with a handheld boom with a hollow cone nozzle (TXVS-26). Applications were made on 16, 23 and 30 Augand 6 and 12 Sep. Disease severity was assessed on 23 and 30 Aug and 6 and 12 Sep as percent leaf area with necrosis per plot. Fruit were harvested on 29 Aug and 6 and 12 Sep. Data were analyzed in the software ARM (Gylling Data Management, Brookings, SD) using analysis of variance (AOV) and Fisher's Protected LSD test to separate means.