Control of Rice Water Weevil on Drill-Seeded Rice with Diflubenzuron at Eagle Lake, 1996

Abstract

Abstract The experiment was conducted at the TAES Western Area Operations at Eagle Lake. The experiment was designed as a RCB with 8 treatments and 4 replications. Each plot was 15 ft X 8 ft surrounded by a metal barrier to prevent movement of insecticide. Plots were drill planted (7.5 inches between rows) on 3 Api at 100 lb seed/acre. Soil type was Nada. Plots were fertilized at planting with 30 lb nitrogen, 38 lb phosphorus, and 40 lb potassium/acre. On 8 Apr, Facet 50WP and Bolero 8EC were applied at 0.35 lb and 2 pt/acre, respectively. Rice emerged 14 Apr after which rice was flush irrigated as needed until application of the permanent flood on 3 May (19 d after rice emergence). On 1 May, Bolero 8EC, Stam 4E, Ordram 8E, and Facet 75DF were applied at 2 pt. 2 qt, 2 pt, and 0.33 lb/acre, respectively. Plots were fertilized immediately before the permanent flood with urea at 70 lb nitrogen/acre. Diflubenzuron treatments were applied with a 4 nozzle (tip size 800067, 50 mesh screens), hand-held, CO2-pressurized spray rig. Final spray volume was 37 gpa. Furadan 3G was applied with a hand-held shaker jar. On 22 May, Londax was applied at 0.1 lb/acre. On each of 29 May and 18 Jun (26 d and 46 d, respectively, aftei application of the permanent flood) five 4 inch diam X 4 inch deep soil cores (each core containing at least 1 rice plant) were removed from each plot. Rice plants in cores were washed and immature RWW recovered from the roots. Plots were fertilized at panicle differentiation (7 Jun) with urea at 50 lb nitro-gen/acre. Thus, total applied nitrogen/acre was 150 lb. The middle 8 rows of each plot were harvested with a small plot combine on 7 Aug. Yields were adjusted to 12% moisture. Insect counts were transformed using x+ 0.5. All data were analyzed by 2-way ANOVA and DMRT