Spray Rig Research Articles

An Evaluation of Spray Rig Designs for California Strawberries Using Water-Sensitive Paper

ABSTRACT The aim of this work was to fill the gap in California pest management by evaluating coverage and spatial uniformity of spray rig designs used in California strawberry production. Coverage can be improved up to 30% if the important design parameters are identified, which would reduce pests. Field evaluations were conducted in beds with 4 canopy lines in Santa Maria, CA on 162 cm beds and in Oxnard, CA on 172 cm beds as well as in beds with 2 canopy lines in Watsonville, CA on 122 cm beds and 132 cm beds. Water-sensitive paper cards placed adaxial and abaxial, both horizontally and vertically on plant canopies located near the middle and edge of the bed were used as the evaluation criteria. Data were analyzed by regression. Results from spray evaluations (n = 21) included recording the nozzle used, manifold height, number of nozzles per bed, volume sprayed, nozzle pressure, and tractor speed, as well as determining the percent coverage from 1,568 water-sensitive spray cards. Increasing nozzle pressure can potentially increase coverage by 9.18%. Positioning the nozzle closer to the canopy level can also significantly increase coverage.

Apparent Soot Size and Concentration in Combusting Diesel Jets at High Gas Pressures and Temperatures Measured by Combining Quasi-Simultaneous LII, Elastic Light Scattering and Light Extinction

<div class="section abstract"><div class="htmlview paragraph">A method for measuring apparent soot particle size and concentration in turbulent combusting diesel jets with elevated and inhomogeneous optical density is presented and discussed. The method is based on the combination of quasi-simultaneous Laser Induced Incandescence (LII), Elastic Scattering (ELS) and Light Extinction (LE) measurements exhibiting a high potential for spatially resolved measurements of carbonaceous particles in flames and residual gases at a given instant. The method evaluates the LII signal by calculating the laser fluence across the flame and compensating for signal trapping, allowing measurements where laser extinction between the flame borders reaches values up to <i>90%.</i> The method was implemented by measuring particle size and concentration in the middle sagittal axis of optically dense, combusting diesel jets at a certain time after the start of combustion. Experiments were carried out in the Chalmers High Pressure, High Temperature spray rig under conditions similar to those prevailing in direct injected compression ignition engines. Measurements of apparent particle size and concentration together with volume fraction conferring an instantaneous single-shot case and an average measurement from several consecutive jets are presented and discussed.</div></div>

Investigation of Small Pilot Combustion in a Heavy-Duty Diesel Engine

Factors influencing pilot-injection combustion were investigated using heat release analysis in a heavy-duty diesel engine fuelled with standard diesel fuel. Combinations of pilot-injection parameters i.e. pilot start of injection, pilot mass, pilot-main injection separation, and rail pressure were studied for various operating conditions and combustion phases. An experiment was designed to investigate the factors influencing the combustion of the pilot. For improved injected fuel-mass accuracy, reference data for the injectors were measured in a spray rig prior to the engine experiments. Results show that cycle-to-cycle variations and cylinder-to-cylinder variations influence pilot autoignition and the amount of heat released. Rail pressure and injected pilot mass affect the obtained variance depending on the chamber conditions. The obtained combustion modes (premixed, diffusive) of pilot combustion were found to be a function of the injected mass and rail pressure. (Less)

Droplet dynamics and size characterization of high-velocity airblast atomization

Airblast atomizers are especially useful and commonplace in liquid fuel combustion applications. However, the spray formation processes, the droplet dynamics and the final drop size distributions are still not sufficiently understood due to the coupled gas-liquid interactions and turbulence generation. Therefore, empirical and semi-empirical approaches are typically used to estimate the global spray parameters. To develop a physical understanding of the spray evolution, a plain-jet airblast atomizer was investigated in an atmospheric spray rig using the phase-Doppler technique. The simultaneous drop size and axial and radial velocity components were measured on radial traverses across the spray at various axial distances from the nozzle for a range of atomizing pressures. The droplet turbulent and mean kinetic energies were found to be proportional to the atomizing pressure. Hence, the scatter of the radial motion of the droplets increased with the atomizing pressure. A droplet stability analysis was performed to locate the regions characterized by ongoing secondary atomization. The volume-to-surface diameter, D32, of the fully developed spray was compared with estimates provided by five published formulae. The role of liquid viscosity, hence the Ohnesorge number, was found to be negligible in the investigated regime. Three commonly used size distribution functions were fitted to the measured data to analyze their dependence on the atomizing pressure. The Gamma distribution function was found to give the best approximation to the atomization process.

Application of disinfectant sprays after chilling to reduce the initial microbial load and extend the shelf-life of chilled chicken carcasses

The objective of this study was to evaluate the effects of various disinfectant sprays on initial microbial load and conduct a shelf-life study of chilled chicken carcasses. Chilled chicken carcass samples obtained after chilling were sprayed for 15 s in a purpose-built spray rig with sodium hypochlorite (SH, 50 & 100 mg/L), chlorine dioxide (CD, 50 & 100 mg/L), lactic acid (LA, 1 & 2%), acid electrolyzed oxidizing water (AEOW) and slightly acid electrolyzed oxidizing water (SAEOW). Untreated carcasses were used as the control. Back, leg and breast skin were removed from each carcass after treatment to determine the total viable counts (TVC) and total coliforms. Sprays of 2% LA, AEOW and SAEOW were the most effective treatments with reductions of 0.47–0.83 log CFU/cm2 and 0.49–0.96 log MPN/cm2 in TVC and total coliforms, respectively. Samples treated with AEOW and SAEOW had 2 days of microbial shelf-life extension compared to the controls, which exceeded the TVC limit of 7 log CFU/cm2 at day 6. Even longer extension was obtained for the 2% LA treated samples. The total coliforms, pH and total volatile basic nitrogen (TVBN).TVBN values of the 2% LA, AEOW and SAEOW treated samples were significantly (P < 0.05) lower than those of the controls during storage. Predominantly, the TBARS values of the AEOW and SAEOW treated samples were not statistically different from those of the controls (P > 0.05); however, the 2% LA treatment accelerated lipid oxidization, manifested as the highest TBARS value (2.09 mg MDA/kg) at day 8. Conclusively, this study indicated that the application of AEOW and SAEOW sprays to chilled chicken carcasses after chilling can reduce initial microbial load and maintain quality attributes during refrigerated storage.

Interior flow and near-nozzle spray development in a marine-engine diesel fuel injector

A consolidated effort at optically characterising flow patterns, in-nozzle cavitation, and near-nozzle jet structure of a marine diesel fuel injector is presented. A combination of several optical techniques was employed to fully transparent injector models, compound metal-glass and full metal injectors. They were all based on a common real-scale dual nozzle hole geometry for a marine two-stroke diesel engine. In a stationary flow rig, flow velocities in the sac-volume and nozzle holes were measured using PIV, and in-nozzle cavitation visualized using high-resolution shadowgraphs. The effect of varying cavitation number was studied and results compared to CFD predictions. In-nozzle cavitation and near-nozzle jet structure during transient operation were visualized simultaneously, using high-speed imaging in an atmospheric pressure spray rig. Near-nozzle spray formation was investigated using ballistic imaging. Finally, the injector geometry was tested on a full-scale marine diesel engine, where the dynamics of near-nozzle jet development was visualized using highspeed shadowgraphy. The range of studies focused on a single common geometry allows a comprehensive survey of phenomena ranging from first inception of cavitation under well-controlled flow conditions to fuel jet structure at real engine conditions.

Characterization of viscous biofuel sprays using digital imaging in the near field region

The atomization of biodiesel, vegetable oil and glycerin has been studied in an atmospheric spray rig by using digital imaging (PDIA). Images of the spray were captured in the near field, just 18 mm downstream of the atomizer, and processed to automatically determine the size of both ligaments and droplets. The effect of the spray structure in this region is of major interest for the combustion of biofuels in gas turbines. The sprays were produced by a pressure-swirl atomizer that originates from the multifuel micro gas turbine (MMGT) setup. Various injection conditions have been tested to investigate the influence of viscosity on the spray characteristics and to assess the overall performance of the atomizer. The spray measurements have been compared to combustion experiments with biodiesel and vegetable oil in the micro gas turbine at similar injection conditions. The results show that the primary breakup process rapidly deteriorates when the viscosity is increased. A higher viscosity increases the breakup length, which becomes visible at the measurement location in the form of ligaments. This effect leads to an unacceptable spray quality once the viscosity slightly exceeds the typical range for conventional gas turbine fuels. The SMD in the investigated spray region was not significantly affected by viscosity, but mainly influenced by injection pressure. The data furthermore indicate an increase in SMD with surface tension. It was found that the penetration depth of ligaments can have major impact on the combustion process, and that the droplet size is not always the critical factor responsible for efficient combustion. The measured delay in primary breakup at increased viscosity shows that pressure-swirl atomization is unsuitable for the application of pure pyrolysis oil in an unmodified gas turbine engine

Comparison of Acidified Sodium Chlorite, Chlorine Dioxide, Peroxyacetic Acid and Tri-Sodium Phosphate Spray Washes for Decontamination of Chicken Carcasses

The objective of this study was to directly compare the antimicrobial effect of acidified sodium chlorite (ASC), chlorine dioxide (CD), peroxyacetic acid (PAA) and tri-sodium phosphate (TSP) on naturally occurring Campylobacter, Enterobacteriaceae and Pseudomonas spp. on the breast and neck skin of chicken carcasses treated post-evisceration and prior to primary chilling. Naturally contaminated Campylobacter-positive chicken carcasses, obtained from a commercial processing line immediately post-evisceration but prior to the inside–outside wash, were treated in a purpose-built automated spray rig. Replicated batch treatments for 15 and 30 s of chemical and water-only spray wash were performed. Untreated control carcasses were examined to provide baseline data for the initial numbers. Numbers of colony-forming units (CFU) per gram of skin excised from neck and breast locations were determined using selective agar media. For analysis, the results were subdivided into six microbe type/skin location combinations with each subdivision ranked by the following: (a) CFU remaining after treatment, (b) mean reductions and (c) the proportional change in numbers of samples below the limit of detection (LoD). The three groups of bacteria responded similarly to the chemicals applied. Campylobacter spp. were no more susceptible than the other two groups. No single chemical treatment gave the best effect across all ranking methods. Generally, ASC and TSP were more effective in reducing microbial counts than PAA, with CD and water having the least effect. A 30-s chemical treatment was usually more effective than a 15-s treatment. Where only a short (15 s) spray time is possible, ASC appears to be the most effective of the chemicals tested. Where longer treatments are possible, TSP becomes the most effective choice.

Time and Spatially Resolved Temperature Measurements of a Combusting Diesel Spray Impinging on a Wall

The interaction between a combusting diesel spray and a wall was studied by measuring the spray flame temperature time and spatially resolved. The influence of injection sequences, injection pressure and gas conditions on the heat transfer between the combusting spray and the wall was investigated by measuring the flame temperature during the complete injection event. The flame temperature was measured by an emission based optical method and determined by comparing the relative emission intensities from the soot in the flame at two wavelength intervals. The measurements were done by employing a monochromatic and non intensified high speed camera, an array of mirrors, interference filters and a beam splitter. The studies were carried out in the Chalmers High Pressure High Temperature (HP/HT) spray rig at conditions similar to those prevailing in a direct injected diesel engine prior to the injection of fuel. Fuel was injected into the combustion chamber by a common rail system using an injector with a single hole nozzle. The combusting spray impinged on a wall whose temperature was similar to the combustion chamber gas temperature. Results of these experiments show variations in the flame temperature as a consequence of the interaction between the combusting spray and the wall. There is a reduction in the flame temperature after impingement followed by a temperature rise as the wall is heated up by the flame. The effects caused by injection pressure, injection sequences and gas temperature lead to differences

Electronic height indicator for agricultural machines

This paper addresses the design and development of a low cost electronic height indicator for a self-propelled spray rig. The prime objective is to give a spray rig operator an accurate indication of the boom height above the ground by using an electronic display in the tractor cabin to improve the efficiency of chemical application. This indicator is implemented using a microcontroller and a Hall-effect sensor. The field test proves that this indicator has improved the spraying performance by eliminating human error in estimating boom height, especially during night-time and dusty conditions.

Models of fuel spray penetration

A brief review of models of diesel fuel spray penetration, developed at the University of Brighton, are presented. These refer to the initial stage of spray penetration and the two-phase flow stage, when the relative velocity between droplets and gas can be ignored. The predictions of the two-phase models of spray penetration are compared with the results of experimental studies. A rapid compression diesel spray rig, based at Brighton University, and a high-pressure dimethyl ether spray chamber, based at Chungbuk National University, have been used. In both cases the experimental results are shown to be in agreement with the prediction of theoretical models.

EVALUATION OF TADS 12253 AND KARATE FOR CONTROL OF INSECT PESTS OF SOYBEANS, 1998

The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont, TX, in 1998 and was designed as an RCB with three treatments and four replications. Plot size was six rows x 50 ft long (30 inches between rows). Treatments are described in the tables. Plots were planted with ‘Haskell’ (Maturity Group VII) on 9 Jun. Seeding rate was eight viable seeds per ft of row. Soybeans emerged 16 Jun. On 7 Oct, when stink bug populations were increasing, selected plots were sprayed with the treatment insecticides. Insecticides were applied with a two-person, 20-ft spray rig (11 nozzles) pressurized with CO2. Nozzle tip size was 800067 and nozzles were equipped with 50 mesh screens. Final spray volume was 29 gpa. Five days before treatment applications, plots were sampled for arthropods with a 15-inch-diameter sweep net. Ten consecutive sweeps were taken in each plot. Arthropods from each sample were transferred to a plastic bag, which was frozen. At a later date, the contents of the bags were thawed, identified, and counted. One, 3, 9, 16, and 23 d after treatment applications, plots were sampled as described above. On each sample date, stage of development of soybeans was recorded. Plots were not harvested because of summer drought conditions that drastically reduced soybean yields. Arthropod counts were transformed using, O x + 0.5 and all data analyzed by ANOVA and means separated by DMRT (P = 0.05).

Control of a Sharpshooter with Exp 80698A and Karate, 1997

Abstract The experiment was conducted in a greenhouse at the TAMU Agricultural Research and Extension Center at Beaumont and was designed as a RCB with 6 treatments and 4 replications. The greenhouse was maintained at 31° C, 70% relative humidity, and 12 h light:12 h dark. Each experimental unit was a pot (6 inch diam X 6 inch deep) filled with sifted League soil. On 30 Sep, selected pots were planted with 8 untreated or EXP 80698A 75 FS-treated seeds. Seeds were treated at the rates shown in the table using the “Le Sak” method developed by Rhone-Poulenc Ag Company. On the same day, selected pots were sprayed with EXP 80698A 75 FS at the rates shown in the table using a 4 nozzle (800067 tip size, 50 mesh screens), hand-held spray rig pressurized with CO2. Final spray volume was 9.0 gpa. On the same day, pots were fertilized with urea at 51 lb nitrogen/acre. Immediately following planting, and spraying, soil in each pot was “raked” with forceps to simulate incorporation. On 5 Oct, rice emerged through soil. On 21 Oct, selected pots were treated with Karate at the rate shown in the table using the same spray rig and final spray volume as before. Immediately after spraying Karate, a plastic cylinder was placed over 2 plants in each pot. Cylinders were 3 inch in diam so that the plant density within a cylinder was equal to a seeding rate of 90 lb/acre, given 100% emergence and survival of seeds. The cylinders were ventilated with screen windows and tops. After securing the cylinders, which served as cages, each was infested on 21 (Oct 17 d after emergence of rice through soil) with 5 adult sharpshooters. Insects were collected from untreated rice using a sweep net. Two d later, cages were inspected for live and dead sharpshooters. Data were expressed as % mortality which was transformed using arcsine. Transformed data were then analyzed by 2-way ANOVA and means separated by DMRT.

Control of Rice Stink Bug with Selected Insecticides, 1997

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. Plot size was 25 ft X 6.5 ft of heading (milk stage) rice. On 4 Aug, selected plots were treated with EXP 61096A 100 EC, Sevin XLR Plus, Fury, and Karate at the rates shown in the table. Insecticides were applied with a 4 nozzle (800067 tip size, 50 mesh screens), hand-held spray rig pressurized with CO2. Final spray volume was 12 gpa. Immediately after application and 24 h, 72 h, and 7 d after application, 4 panicles were randomly removed from each plot. Immediately after removal, severed panicles were transported to a greenhouse maintained at 31° C, 70% relative humidity, and 12 h light: 12 h dark. Each set of 4 panicles was caged in a transparent plastic cylinder ventilated with screen windows and a screen top. The severed ends of the panicles were inserted in moist sand contained in a styrofoam cup. The bottom of the cage was secured in the moist sand. Once panicles and cages were in place, each cage was infested with 10 adult RSB collected by sweep net from untreated rice. Forty-eight h after infestation, cages were inspected for live and dead insects. Data was expressed as % mortality which was transformed using arcsine. Transformed data were then analyzed by 2-way ANOVA and means separated by DMRT.

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

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.

Control of Rice Water Weevil with Dimilin 2 L in a Drill-Seeded, Delayed Flood Culture at Eagle Lake, 1997

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 and surrounded by a metal barrier to prevent movement of insecticide and fertilizer. Plots were drill planted (7.5 inches between rows) on 15 Apr at 80 lb seed/acre. Soil type was Nada. Plots were fertilized at planting with 45 lb nitrogen/acre, 38 lb phosphorus/acre, and 40 lb potassium/acre. Rice emerged through soil on 25 Apr. From emergence of rice through soil to application of the permanent flood on 22 May (27 d after application of the permanent flood), plots were flushed irrigated (24 h temporary flood then drain) as needed. On 24 Apr, plots were sprayed with Wham EZ at 1 qt/acre, Bolero 8 EC at 2 pt/acre, and Facet 75 DF at 0.25 lb/acre. On 16 May, plots were sprayed with Wham EZ at 3 qt/acre. Facet 75 DF at 0.25 lb/acre, and Londax at 0.05 lb/acre. On 21 May, plots were fertilized with urea at 60 lb nitrogen/acre. On 24 May (2 d application of the permanent flood), selected plots were sprayed with Dimilin 2 L at the rates shown in the table. On 2 Jun (lid after application of the permanent flood), selected plots were sprayed with Dimilin 2 L at the rates shown in the table. Sprays were applied with a 4 nozzle (tip size 800067, 50 mesh screens), hand-held spray rig pressurized with CO2. Final spray volume was 16.0 gpa. On 5 Jun (14 d after application of the permanent flood), selected plots were treated with Furadan 3 G at 20 lb/acre using a hand-held shaker jar. On 13 Jun, plots were sprayed with Londax at 0.05 lb/acre. On 25 Jun, plots were fertilized with urea at 50 lb nitrogen/acre; thus, total nitrogen applied during the entire growing season was 155 lb/acre. On each of 12 Jun and 25 Jun (21 and 34 d, respectively, after application of the permanent flood), 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. On 12 Jul, plots were sprayed with Sevin XLR Plus at 1 qt/acre to control rice stink bug. The middle 8 rows of each plot were harvested on 26 Aug (123 d from emergence of rice through soil). Yields were adjusted to 12% moisture. Insect counts were transformed using x + 0.5 and all data analyzed by 2-way ANOVA and DMRT.

Control of Rice Water Weevil with Karate in a Water-Seeded, Pinpoint Flood Culture, 1997

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 and fertilizer. On 19 Apr, plots were fertilized with urea at 113 lb nitrogen/acre and treated with Ordram 15 G at 27 lb/acre. Fertilizer and herbicide were applied by hand and incorporated into dry League soil with a rake. Immediately after incorporation, plots were flooded. On 21 Apr, plots were hand-planted with sprouted seed at 120 lb dry seed/acre. Sprouted seed was prepared by soaking untreated seed for 24 h in water and then draining and drying for 24 h. On 25 Apr, plots were drained and 4 d later plots were reflooded. On 1 May, rice emerged through water. (On 5 May (4 d after emergence of rice through water), selected plots were sprayed with Karate at the rates shown in the table. At this time, adult RWW feeding scars were observed on rice foliage; indicating the presence of active adults in the plots. 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 19 May (18 d after emergence of rice through water), selected plots were treated a second time with Karate at the rates shown in the table. Karate was applied with a 4 nozzle (tip size 800067, 50 mesh screens), hand-held spray rig pressurized with CO2 to deliver 16 gpa. Final spray volume was 16.0 gp. On 22 May, 6 Jun, and 10 Jul, plots were fertilized by hand with urea at 30 lb nitrogen/acre; thus, total nitrogen applied during the growing season was 203 lb/acre. On each of 27 May and 9 Jun (26 and 39 d 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, washed, and inspected for immature RWW. At maturity, plots were harvested (16 Aug = 107 d after rice emergence 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.

Control of Rice Water Weevil with Karate in a Drill-Seeded, Delayed Flood Culture at Eagle Lake, 1997

Abstract The experiment was conducted at the TAES Western Area Operations at Eagle Lake. The experiment was designed as a RCB with 4 treatments and 4 replications. Each plot was 15 ft X 8 ft and was surrounded by a metal barrier to prevent movement of insecticide and fertilizer. Plots were drill planted (7.5 inches between rows) on 15 Apr at 80 lb seed/acre. Soil type was Nada. Plots were fertilized at planting with 45 lb nitrogen/acre, 38 lb phospho-rus/acre, and 40 lb potassium/acre. Rice emerged through soil on 25 Apr. From emergence of rice through soil to application of the permanent flood on 22 May (27 d after application of the permanent flood), plots were flush irrigated (24 h temporary flood then drain) as needed. On 24 Apr, plots were sprayed with Wham EZ at 1 qt/acre, Bolero 8 EC at 2 pt/acre and Facet 75 DF at 0.25 lb/acre. On 16 May, plots were sprayed with Wham EZ at 3 qt/acre, Facet 75 DF at 0.25 lb/acre, and Londax at 0.05 lb/acre. On 21 May, plots were fertilized with urea at 60 lb nitrogen/acre. On 24 May (2 d after application of the permanent flood), selected plots were sprayed with Karate at the rates shown in the table using a 4-nozzle (tip size 800067, 50 mesh screens), hand-held spray rig pressurized with CO2. Final spray volume was 1.60 gpa. At the time of Karate application, adult RWW were present in the plots. On 5 Jun (14 d after application of the permanent flood), selected plots were treated with Furadan 3 G at 20 lb/acre using a handheld shaker jar. On 13 Jun, plots were sprayed with Londax at 0.05 lb/acre. On 25 Jun, plots were fertilized with urea at 50 lb nitrogen/acre; thus, total nitrogen applied during the entire growing season was 155 lb/acre. On each of 12 Jun and 25 Jun (21 and 34 d, respectively, after application of the permanent flood), 5, 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. On 12 Jul, plots were sprayed with Sevin XLR Plus at 1 qt/acre to control rice stink bug. The middle 8 rows of each plot were harvested on 26 Aug (123 d from emergence of rice through soil). Yields were adjusted to 12% moisture. Insect counts were transformed using x + 0.5 and all data analyzed by 2-way ANOVA and DMRT.

Control of Rice Water Weevil with Exp 80698A 75 Fs Applied After the Permanent Flood in a Dry-Seeded, Delayed Flood Culture, 1997

Abstract The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont and was designed as a RCB with 5 treatments and 4 replications. Each plot was 15 ft X 8 ft and surrounded by a metal barrier to prevent movement of insecticides and fertilizer. On 1 May, plots were fertilized with urea at 113 lb nitrogen/acre and planted with 100 lb of untreated or EXP 80698A 75 FS-treated seed/acre at the rate shown in the table. Fertilizer and seed were incorporated into dry league soil with a rake. Immediately after incorporation, plots were flushed (24-48 h temporary flooding, then draining). Rice emerged through soil on 9 May. On 28 May, plots were sprayed with Facet 75 DF at 0.5 lb/acre, crop oil concentrate at 2 pt/acre, Prowl 3.3 EC at 2 pt/acre, and Basagran at 1.5 pt/acre. Herbicides were applied by hand with a 20 ft spray boom pressurized with CO2. Immediately before the permanent flood on 30 May (21 d after emergence of rice through soil), selected plots were treated with EXP 80698A 75 FS at 0.05 lb (AI)/acre. On 2 Jun, (3 d after application of the permanent flood), selected plots were treated with EXP 80698A 75 FS at 0.05 lb (AI)/acre and Karate at 0.03 lb (AI)/acre. All liquid insecticides were applied with a 4 nozzle (tip size 800067, 50 mesh screens) hand-held, spray rig pressurized with CO2. Final spray volume was 16.0 gpa. On 16 Jun and 10 Jul, plots were fertilized with urea at 50 and 30 lb nitrogen/acre, respectively; thus, total nitrogen applied during the growing season was 193 lb/acre. On each of 25 Jun and 10 Jul (26 and 41 d, respectively, after application of the permanent flood), 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 (5 Sep = 119 d from emergence of rice through soil) 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.

Control of Rice Water Weevil with Exp 61096A 100 Ec and Exp 60949A 1.5 G in a Dry-Seeded, Delayed Flood Culture, 1997

Abstract The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont and was designed as a RCB with 7 treatments and 4 replications. Each plot was 15 ft X 8 ft and surrounded by a metal barrier to prevent movement of fertilizer and insecticides. Or 2 May, plots were fertilized with urea at 113 lb nitrogen/acre and hand planted with 100 lb seed/acre. Fertilizer and seed were incorporated into dry League soil with a rake. Immediately after incorporation, plots were flush irrigated (temporary flood for 24-48 h then drain). On 10 May, rice emerged through the soil. From emergence of rice through soil to application of the permanent flood on 30 May (20 d after rice emergence through soil), rice was flush irrigated as needed. On 28 May, plots were sprayed with Facet 75 DF at 0.5 lb/acre, crop oil concentrate at 2 pt/acre, Prowl 3.3 EC at 2 pt/acre, and Basagrar at 1.5 pt/acre. Herbicides were applied with a 2-person, 20 ft spray boom pressurized with CO2. Immediately before application of the permanent flood EXP 61096A 100 EC and EXP 60949A 1.5 G were applied at the rates in the table to selected plots. Granular insecticide was applied with a hand-held shaker jar. On 2 Jun (3 d after application of the permanent flood), EXP 61096A 100 EC and Karate 1 EC were applied at the rates in the table to selected plots. Liquid formulations of insecticides were applied with a 4 nozzle (tip size 800067, 50 mesh screens), hand-held spray rig pressurized with CO2. Final spray volume was 16.0 gpa. On 16 Jun and 10 Jul, plots were fertilized with urea at 50 and 30 lb nitrogen/acre, respectively; thus, total nitrogen applied during the growing season was 193 lb/acre. On each of 28 Jun and 9 Jul (29 and 40 d, respectively, after application of the permanent flood), 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 (22 Aug = 104 d from emergence) with a small plot combine. Yields were adjusted tc 12% moisture. Insect counts were transformed using x + 0.5 and all data analyzed by 2-way ANOVA and DMRT.