Control of Rice Water Weevil with Exp 80698A 75 Fs in a Water-Seeded, Pinpoint Flood Culture, 1997

Abstract

Abstract The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont and was designed as a RCB with 6 treatments and 4 replications. Each plot was 15 ft X 8 ft and surrounded by a metal barrier to prevent movement of insecticide. On 19 Apr, plots were fertilized with urea at 113 lb nitrogen/acre and treated with Ordram 15 G at 17 lb/acre. Selected plots were sprayed with selected insecticide treatments on 19 Apr using a 4 nozzle (tip size 800067, 50 mesh screens); hand-held spray rig pressurized with CO2. Final spray volume was 16 gpa. The insecticides were incorporated into dry League soil using a rake. Immediately after incorporation, plots were flooded. On 22 Apr, plots were planted with sprouted seed at 120 lb dry seed/acre. Sprouted seeds were prepared by soaking untreated, dry seed for 24 h followed by draining and drying for 24 h. Selected plots were hand planted with selected seed treatments which were applied using the “Le Sak” method in which sprouted seed was placed in a plastic bag and insecticide poured over the seed. The seed and insecticide were mixed inside the bag until seed adsorbed all insecticide. The bag was opened and insecticide allowed to dry on seed. On 25 Apr, plots were drained and reflooded 29 Apr. Rice in most treatments emerged through water on 1 May; however, untreated rice and rice seed treated with EXP 80698A at 0.05 lb (AI)/acre did not emerge through water for 1 to 3 d later. On 10 May (9 d after emergence of rice through water), selected plots were treated with Furadan 3 G at 20 lb/acre using a hand-held shaker jar. On each of 22 May, 11 Jun, and 10 Jul, plots were fertilized with urea at 30 lb nitrogen/acre; thus, total nitrogen applied to plots during the growing season was 203 lb/acre. On each of 28 May and 10 Jun (27 and 43 d, respectively, after emergence of rice through water), five 4-inch diam X 4 inch deep soil cores (each containing at least 1 rice plant) were removed from each plot. Rice plants in cores were washed and immature RWW recovered from the roots. At maturity, plots were harvested (15 Aug = 106 to 109 d after emergence of rice through water) with a small plot combine. Yields were adjusted to 12% moisture. Insect counts were transformed using x + 0.5 and all data analyzed by 2-way ANOVA and DMRT.