Evaluation of fungicides and cultivars 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 and non-treated guard rows on each side. The previous year the field was planted with sweetpotato. Cucumber was direct seeded on 17 Jul (2-ft in-row spacing, 2 seed/hill) and thinned to one plant per hill after emergence (7 plants/plot). Two non-treated commercial cucumber varieties were includedin the trial in addition to non-treated Liszt and Liszt treated with different fungicide applications. 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 hollow cone nozzle (TXVS-26). Applications were made on 8, 14, 21 and 28 Aug and 4 Sep. Disease severity was assessed on 14, 21 and 28 Aug and 4 and 12 Sep as percent leaf area with necrosis per plot. Fruit were harvested on 7, 13, 21 and 27 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.