Control of Rice Water Weevil With Fipronil in A Dry-Seeded, Delayed Flood Culture, 1996

Abstract

Abstract The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont. The experiment was designed as a RCB with 10 treatments and 4 replications. Each plot was 15 ft X 8 ft and surrounded by a metal barrier to prevent movement of insecticides. On 8 Apr, plots were fertilized by hand with urea at 68 lb nitrogen/acre. On the same day, plots were dry-seeded by hand with fipronil-treated or untreated seed at 90 lb/acre. Fipronil-treated seed was provided by Rhone-Poulenc Ag Company. Pre-plant incorporated treatments were applied on 8 Apr with a 4 nozzle (tip size 800067, 50 mesh screens), hand-held, spray rig pressurized with CO2. Final spray volume was 29.7 gpa. After spray applications, fertilizer, seed, and spray treatments were incorporated into dry soil (League) with a rake. Immediately after incorporating, plots were flush irrigated (temporarily flood for 24 h then drain). Rice emerged through the soil on 18 Apr. From emergence to application of the permanent flood on 10 May (22 d after rice emergence through soil), rice was flush irrigated as needed. On 30 Apr, plots were treated with Stam 4E and Basagran at 4.0 lb and 1.0 lb (AI)/acre, respectively. On 9 May, plots were treated again with Stam 4E and Basagran at 2.0 lb and 1.0 lb (AI)/acre, respectively. On 10 May (immediately before application of the permanent flood), plots were fertilized with urea at 51 lb nitrogen/acre. Furadan 3G was applied with a hand-held shaker jar 14 d after application of the permanent flood. On 4 Jun (approximately panicle differentiation), urea was applied by hand at 51 lb nitrogen/acre; thus, total nitrogen applied to rice was 170 lb/acre. On each of 6 and 25 Jun (27 and 46 d after application of the permanent flood) five 4 inch diameter by 4 inch deep soil cores (each core containing at least 1 rice plant) were removed from each plot, washed, and inspected for immature RWW. At maturity (5 Aug) plots were harvested with a small plot combine and yields adjusted to 12% moisture. Insect counts were transformed using (x + 0.05) and all data analyzed by 2-way ANOVA and DMRT.