Oil-based Spray Research Articles

Farm Fields as Toxic Sinkhole

Farm Fields as Toxic Sinkhole

Influence of encapsulating materials on spray-dried palm oil-based powder

The present study was carried out to study the development of palm oil-based spray dried fat powder using three different encapsulating wall materials namely TSLP (Sodium caseinate + Lactose), TSMP (Sodium caseinate + Maltodextrin), and TSHAP (Sodium caseinate + Hi-Cap + Acacia gum). Results revealed that TSHAP has the lowest moisture content (6.66%) and water activity (0.591%) after 60 days of storage at the room temperature. Further, higher surface oil values (nearly 30% of total oil) were obtained for all three combinations of wall material. The peroxide value of encapsulated palm oil increased with an increase in storage period but was found to be less than unencapsulated oil. Bulk density ranged from 0.2974 to 0.342 g/cm3 for TSLP and TSHAP, respectively whereas, tapped density was found to range from 0.3875 to 0.4675 g/cm3. These developments can find relevant applications in the bakery and dairy industry.

Challenges of Aircraft and Drone Spray Applications

Crop protection on major crops is now required to follow the principles of integrated pest management so the timing and accuracy of any application of a pesticide or biopesticide has to be more precise to minimize adverse effects on non-target species. The development of UAVs (unmanned aerial vehicles) provides a means of providing a more targeted application of the correct dose, especially by using formulations that are more persistent, thus minimizing loss of spray in areas subject to rain. Avoiding use of too high a dosage allows greater survival of natural enemies and reduces the selection pressure for pests becoming resistant to specific modes of action. The downward flow of air from a UAV should also provide better distribution and impaction of droplets within a crop canopy, reduce soil impaction caused by taking heavy loads of spray applied with 200 l ha–1 of water, and allow treatments when fields are too wet to access with ground equipment. In Asia, many smallholder farmers are using a drone in preference to using a knapsack sprayer. According to Matthews, it has been shown that ULV spraying can be effective, but it needs a narrow droplet spectrum with the droplets remaining stable and not shrinking to become too small. Formulation research can reduce the volatility of the spray, hence the success of oil-based sprays. However, instead of petroleum-based oils, there is a chance to develop vegetable oil carriers with micro-sized particle suspensions to deliver low toxicity pesticides in droplets that can be deposited within the crop and not drift beyond the crop boundary. Oil deposits will be less prone to loss after rain so less should be lost in neighbouring ditches and water courses, especially as rainfall patterns are forecast to change. More studies are needed to evaluate the swath for deposition, buffer zones, formulation, nozzle selection, to guide future specific legislation for UAV applications.

Assessment of Barrier Materials to Protect Plants from Florida Leatherleaf Slug (Mollusca: Gastropoda: Veronicellidae)

Potential barrier materials (diatomaceous earth, hydrated lime, sulfur, fumed silica, wood ash) and chemical repellents (2 essential oil-based sprays) were evaluated for their efficacy to prevent herbivory by the Florida leatherleaf slug, Leidyula floridana (Leidy, 1851) (Gastropoda: Veronicellidae) by placing a band of material around the plant tissue or by direct application to foliage. Hydrated lime and sulfur effectively prevented foliage damage compared with the other 3 materials when presented as barriers. Dusting or sprinkling these barrier materials on foliage generally did not inhibit feeding by slugs, but sprinkling hydrated lime or wood ash onto foliage significantly reduced herbivory. Two commercially available essential oil formulations were evaluated for their effectiveness at repelling L. floridana. Pure ‘N’ Natural Snail & Slug Away (a cinnamon oil-based product) was quite effective whereas Slug & Snail Defense (containing cedar oil, pine oil, peppermint oil, and white pepper) was ineffective. Contact toxicities of barrier materials and essential oil products were assessed, and compared with a metaldehyde-based bait (Corry's Slug and Snail Pellets), an iron phosphate-based bait (Ecosense Slug and Snail Pellets), and a sulfur-based bait (Ortho Bug-getta Snail and Slug Killer2). Mortality of slugs was high when slugs were exposed to metaldehyde, hydrated lime, and the cinnamon oil-based spray. Iron phosphate bait, sulfur bait, and fumed silica were less effective but provided some reduction in herbivory. Soil moisture adversely affected efficacy of barrier materials, significantly compromising functionality relative to dry soils. Water uptake from soil by barrier materials was positively correlated with foliage consumption but pH was negatively correlated. Because of the negative correlation of pH with consumption, the negative effects of soil moisture on barrier effectiveness, and the rapid physiological response of slugs to some materials, these barrier materials are perhaps better considered to be physiochemical barriers rather than physical barriers.

Multiyear Evaluation of an Orange Peel Oil-based Spray Additive for Managing Insect Pests and Brown Rot of Nectarine

Adjuvants are often added to pesticide formulations to enhance their effectiveness. In this multiyear field study, a proprietary formulation of orange peel oil-based spray additive containing alcohol ethoxylate (OPO-AE) was used alone or in combination with the pyrethroid insecticide esfenvalerate or the demethylation inhibitor fungicide fenbuconazole for pest and disease control of nectarine. Field performance of fenbuconazole for preharvest and postharvest brown rot control was not improved when OPO-AE was added to the spray tank. However, OPO-AE alone reduced preharvest but not postharvest fruit rot compared to the nontreated control. Esfenvalerate was consistently the best treatment to control chewing insects but the insecticidal effect of the pyrethroid was negated when the adjuvant was added. Leaf damage likely due to insect feeding was significantly higher in the esfenvalerate + OPO-AE treatment compared to esfenvalerate alone. The OPO-AE treatment by itself had significantly greater leaf damage compared to the untreated control indicating that the orange peel oil-based formulation is an insect attractant likely due to the presence of d-limonene. In conclusion, our studies do not support claims that OPO-AE formulated as Vintre increases insecticidal or fungicidal efficacy of commercial products. Accepted for publication 14 May 2012. Published 17 June 2012.

Samplers for Evaluation and Quantification of Ultra-Low Volume Space Sprays1

A field study was conducted to explore the suitability of 5 pesticide deposition samplers for airborne spray and ground deposits from ultra-low-volume (ULV) space sprays. Samplers included horizontally stretched stationary cotton ribbons at 2 heights, rotating ribbon, rotating Teflon slides, and filter paper. Slides were also used for droplet-size analysis. A set of 7 samplers of each type was placed at 1, 7, 15, 25, 40, 65, and 90 m from the spray line along the spray swath. Water and BVA13 oil with fluorescent dyes as tracers were sprayed with the use of a truck-mounted ULV sprayer at dusk and dawn. Results suggest that the horizontal and rotating cotton ribbons are best for quantification of airborne spray and filter paper is best for ground deposition collection. The rotating slide samplers only detected the BVA13 oil-based sprays.

Spray Characterization of Ultra-low–volume Sprayers Typically Used in Vector Control1

Numerous spray machines are used to apply pesticides for the control of human disease vectors, such as mosquitoes and flies, and the selection and setup of these machines significantly affects the level of control achieved during an application. The droplet spectra produced by 9 different ultra-low-volume sprayers with oil- and water-based spray solutions were evaluated along with 2 thermal foggers with the use of diesel-based spray solutions. The droplet spectra from the sprayers were measured with the use of laser diffraction droplet sizing equipment. The volume median diameter from the sprayers ranged from 14.8 to 61.9 microm for the oil-based spray solutions and 15.5 to 87.5 microm for the water-based spray solutions. The 2 thermal foggers generated sprays with a volume median diameter of 3.5 microm. The data presented will allow spray applicators to select the spray solution and sprayer that generate the droplet-size spectra that meet the desired specific spray application scenarios.

Efficacy of Entomopathogenic Fungi in Suppressing Pecan Weevil,Curculio caryae(Coleoptera: Curculionidae), in Commercial Pecan Orchards

Abstract. The pecan weevil, Curculio caryae (Horn), is a key pest of pecans, Carya illinoinensis (Wangenh.) K. Koch. The entomopathogenic fungi Beauveria bassiana (Balsamo) Vuillemin and Metarhizium anisopliae (Metschnikoff) Sorokin are pathogenic to and are being developed as microbial control agents for pecan weevil. One approach to suppressing pest populations and the resultant damage might be to apply entomopathogenic fungi when adult pecan weevils are emerging from the soil. Here we report the efficacy of B. bassiana (GHA strain) and M. anisopliae (F52 strain) applied to trees in orchards at three locations: Byron, GA, Fort Valley, GA, and Comanche, TX. At Fort Valley, treatments included B. bassiana as an oil-based spray with a UV-protective screen applied to the trunk, M. anisopliae applied as an impregnated fiber band stapled onto the trunk, and a nontreated check. At Byron, GA, we compared the B. bassiana trunk treatment to a nontreated check. Treatments at the Texas location were the B. bassiana...

CHARACTERIZATION OF TRUCK-MOUNTED ATOMIZATION EQUIPMENT TYPICALLY USED IN VECTOR CONTROL1

The control of medically important arthropod vectors of human and animal disease is a high priority for both public health and military officials. Because droplet size of pesticide spray material is a critical factor affecting vector control applications, the droplet-size spectra produced by 11 sprayers and 3 spray formulations were evaluated. Droplet-size spectra were measured by a laser diffraction instrument, a hot-wire system, and rotating slides. There were considerable differences in the droplet-size spectra produced by the different sprayers tested. The volume median diameter (Dv0.5) for the water-based sprays ranged from 4.7 to 211 microm, depending on the sprayer, and the percent of spray volume contained in droplets less than 20 microm (%vol <20 microm) ranged between 0.5% and 98.9%. The Dv0.5 measurements for the oil-based sprays ranged from 9.4 to 125.3 microm and the %vol <20 microm ranged between 2.4% and 97.9%. The correlations between the Dv0.5 measured by the laser system (Dv0.5-laser) and the mass median diameter, Sauter diameter, and Dv0.5 measured by the AIMS probe were all significant. Generally, the slide Dv0.5s were numerically similar to the Dv0.5 from the laser system and the Sauter diameter from the Army Insecticide Measuring System probe. There was less consistent agreement between the % <32 microm values obtained from the slides and those from the other 2 samplers. The information presented can be used by applicators to select the sprayer that produces the droplet-size spectra needed for their particular application situation.

Study of lubricant-induced changes in chronic snorers (SLICCS)

The efficacy of many of the noninvasive treatments for snoring has not been evaluated in controlled trials. This paper seeks to evaluate the efficacy of an oil-based spray in the treatment of snoring, in a double-blinded, placebo-controlled, crossover trial using objective acoustic analysis and subjective questionnaires. Participants were randomized to use both oil-based oral spray (treatment) and water-based oral spray (placebo) during a two-night in-home study period. Questionnaires were completed by participant and bed-partner in addition to audio-tape recordings which were analyzed for frequency, duration, and mean energy of snoring. Greatest snoring rate demonstrated 30% = benefit; 40% = no change; 30% = adverse effect (n = 20). Percent time snoring yielded: 30% benefit; 15% no change; 55% adverse effect (n = 20). Study data results for mean energy were (n = 12): benefit = 17%, no change = 33%, adverse effect = 50%. Bed-partner observations (n = 17) demonstrated 37% = benefit; 38% = no change; 25% = adverse effect. Objective and subjective evaluation of the performance of the oil-based Snoreless spray in comparison to placebo demonstrated a lack of efficacy in snoring reduction.

Study of lubricant-induced changes in chronic snorers

Problem: The efficacy of many of the noninvasive treatments for snoring has not been evaluated in controlled trials. This study seeks to evaluate the efficacy of an oil-based spray in the treatment of snoring, in a double-blinded, placebo-controlled, cross-over trial using objective acoustic analysis and subjective questionnaires. Methods: Participants were randomized to use both oil-based oral spray (treatment) and water-based oral spray (placebo) during a 2-night in-home study period. Questionnaires were completed by the participant and his/her bed-partner; these were evaluated along with audiotape recordings, which were analyzed for frequency, duration, and mean energy of snoring. Results: Greatest snoring rate demonstrated 30% = benefit; 40% = no change; 30% = adverse effect (n = 20). percent time snoring yielded: 30% = benefit; 15% = no change; 55% = adverse effect (n = 20). Study data results for mean energy were (n = 12): 17% = benefit; 33% = no change; 50% = adverse effect. Bed-partner observations (n = 17) demonstrated 37% = benefit; 38% = no change, 25% = adverse effect. Conclusion: Objective and subjective evaluation of the performance of the oil-based Snoreless spray in comparison to placebo demonstrated a lack of efficacy in snoring reduction. Significance: Study findings indicate that oil-based oral sprays are not effective in the treatment of snoring. Support: None reported.

The Effects of an Entomopathogenic Fungus, Beauveria bassiana (Balsamo) Vuillemin (Hyphomycetes), on Prostephanus truncatus (Horn) (Col.: Bostrichidae), Sitophilus zeamais Motschulsky (Col.: Curculionidae), and Grain Losses in Stored Maize in the Benin Republic

A fungal entomopathogen, Beauveria bassiana, was used to treat maize ears placed in traditional grain stores against Prostephanus truncatus in a field experiment conducted from September 1997 to March 1998 in the Benin Republic, West Africa. Treatments included oil-based spray with and without conidia, maize stored with and without the husk, and stores with and without artificial infestation. Additional treated ears kept in insect-proof cages under field conditions were sampled weekly and exposed to insects to estimate the virulence and persistence of the pathogen during the storage season. P. truncatus densities were significantly lower in treatments that included conidia, although densities were high in all artificially infested treatments and grain losses were severe. The effect of the pathogen was modeled with an exponential decay function and incorporated in a published P. truncatus simulation model. The effects of hypothetical pathogens with different virulence and persistence characteristics were evaluated in terms of insect density and percentage grain loss.

Dengue vector control: present status and future prospects.

Dengue Fever (DF) and Dengue Haemorrhagic Fever (DHF) have been the most common urban diseases in Southeast Asia since the 1950s. More recently, the diseases have spread to Central and South America and are now considered as worldwide diseases. Both Aedes aegypti and Aedes albopictus are involved in the transmission of DF/DHF in Southeast Asian region. The paper discusses the present status and future prospects of Aedes control with reference to the Malaysian experience. Vector control approaches which include source reduction and environmental management, larviciding with the use of chemicals (synthetic insecticides and insect growth regulators and microbial insecticide), and adulticiding which include personal protection measures (household insecticide products and repellents) for long-term control and space spray (both thermal fogging and ultra low volume sprays) as short-term epidemic measures are discussed. The potential incorporation of IGRs and Bacillus thuringiensis-14 (Bti) as larvicides in addition to insecticides (temephos) is discussed. The advantages of using water-based spray over the oil-based (diesel) spray and the use of spray formulation which provide both larvicidal and adulticidal effects that would consequently have greater impact on the overall vector and disease control in DF/DHF are highlighted.

Control of Spruce Budworm (Lepidoptera: Tortricidae) Eastern Canada with the Experimental Mexacarbate Formulation Zectran UCZF19

The experimental mexacarbate formulation Zectran UCZF19 was effective in controlling spruce budworm, Choristoneura fumiferana (Clemens), in a trial conducted during 1984 in eastern Canada. The formulation was mixed in both water and an oil-based diluent and applied as double applications at 70 g (AI) in 1.5 liters tank mix per ha with an aircraft (Cessna Ag-truck) equipped with four atomizers (Micronair AU3000). The aqueous mix produced significantly greater percentages of <50 μm-diameter droplets than oil-based sprays. High spruce budworm population reductions (85 and 84% corrected mortality) and low defoliation of balsam fir, Abies balsamea (L.) Mill., in blocks treated with oil-based and aqueous sprays (8.6 and 17.3%, respectively) were significantly different from those in untreated blocks.

Evaluation of insecticide residues and droplet drift following aerial application to cotton in New South Wales.

In a study to determine the extent of off target drift from aerial spraying, insecticides were applied to cotton crops in various strengths of crosswind by an aircraft fitted with rotary atomizers. Both water-based and oil-based sprays were applied, at 20 and 2 litres/ha respectively. Compared with the mean insecticide deposit across a 16-m target swath, in seven runs, the mean recoveries of insecticide 15, 165 and 3 15 m downwind from the edge of the swath were 6.8, 0.13 and 0.002% respectively. Deposition on plants was nearly twice that on the ground, but the proportional decline downwind was similar. Counts of droplets deposited on paper targets fixed to masts showed that the dispersing cloud of water-based spray contracted more rapidly than did that of the oil-based spray, probably because of greater evaporation of the former. The results indicate that a 300-m wide buffer zone between target crops and areas susceptible to contamination should be adequate under most conditions.

Deposition and biological efficacy of a fungicide applied in charged and uncharged sprays in cereal crops

Barley and wheat crops were both sprayed at growth stages 30 and 61–75 with boom-mounted conventional hydraulic nozzles (250 ℓ/ha), experimental hydraulic electrostatic nozzles (66 ℓ/ha), electrically driven spinning discs (2 ℓ/ha, oil-based sprays and 5 ℓ/ha, aqueous spray) and ‘Electrodyn’ nozzles (1 and 2 ℓ/ha, oil). The ULV spray systems (up to 5 ℓ/haS) were used with or without air assistance. The distribution of both oil and aqueous sprays within the crops was measured with fluorescent tracers on plant parts and on whole plants. An experimental triazole fungicide (mixed with tracer) was applied to the crops by all the spray systems and the degree of control of leaf blotch (scald) caused by Rhynchosporium secalis (Oudem.) J.J. Davis in barley and mildew ( Erysiphe graminis DC) in wheat compared with the deposit data. The two highest-volume spray systems gave similar results for disease control and there was no significant difference between the charged and uncharged sprays at 66 ℓ/ha. The Micron Ulva spinning disc and ‘Electrodyn’ systems with air assistance also performed well. Unassisted ULV sprays were often unevenly distributed within the crops and gave inferior disease control. The ‘Electrodyn’ system often produced large total deposits relative to other spray systems but unassisted sprays were mainly deposited on the upper plant parts. The results indicate that application at volumes as low as 1 ℓ/h can be as biologically effective as conventional high-volume spraying, when compared at the same dose rate of fungicide (90 g/ha). Relationships between spray distribution within cereals and the sites for pest and disease attack are discussed with regard to different methods of application.

THE DISTRIBUTION OF AERIALLY-APPLIED SPRAY DEPOSITS IN SPRUCE TREES

AbstractA plot of 6 m tall white spruce trees was treated with an aerial application of an oil-base spray containing a non-toxic compound, Tris (2 ethyl hexyl) phosphate (referred to as TOF), which was amenable to gas-liquid chromatographic analysis The spray was formulated and applied at a rate to approximate the eastern Canadian operational spruce budworm control sprays. Meteorological measurements were made in the airspace from mid-crown height to the height of spray emission for the period of spray application and deposition. Spray deposit collection units (kromekote cards and glass plates) were used to record spray deposit at ground level.Foliage samples and complete branches were taken from each of three trees at a series of heights and each of the four compass quadrants and returned to the laboratory for chemical analysis. Spray deposit was determined in terms of ppm TOF on the foliage. The kromekote cards provided information from which the drop size characteristics of the spray cloud and the deposit in terms of drops/cmK were determined; a colorimetric analysis of spray deposit on the glass plates indicated the volume of spray deposited.Analysis of the spray deposits on the foliage indicated gradients in deposits with most on the upper, outer, upwind portions of the trees and least on the lower, inner, downwind portions. These differences were significant. These gradients can be attributed to two weather factors (a) the prevailing wind drifting the pesticide cloud through the forest canopy resulting in a filtering to produce a decreasing gradient from upwind to downwind side of the tree, and (b) air eddies around the tree tops resulting in an increased deposit and slight penetration of the spray cloud on the outer downwind portions of the tree.This study demonstrates that a finely atomized spray applied to a white spruce forest under suitable weather conditions will give a deposit on the outer portions of the tree with a variation of only about 50% in spray deposit but with significantly less deposit on the inner, lower portions of the tree.

Oil-based and water-based Ciodrin sprays for fly control on dairy cattle.

Tests were conducted during the summer of 1964 to compare the effectiveness of oil-based and water-based sprays containing 2% Ciodrin® ( alpha -methylbenzyl 3-hydroxycrotonate dimethyl phosphate) against flies on dairy cows. Major species infesting the animals were the face fly, Musca autumnalis DeGeer; the stable fly, Stomoxys calcitrans (L.); and the horn fly, Haematobia irritans (L.). Forty lactating and 10 dry Holstein cows on the Pennsylvania State University Farm were employed as treated animals and untreated controls. The sprays were applied by a newly developed “pushbutton“ spraying device, manually operated and especially designed to give thorough coverage of the faces of the cows. The major parts of the device included an inverted U-shaped pipe system plus an extension in front, 4 nozzles each connected to a solenoid valve, a pump and motor assembly, and an extension wire terminating in a push-button switch. Counts of flies were made daily. Effectiveness of treatments was evaluated on the basis of average reduction percentages in fly populations on treated animals calculated by comparing numbers of flies on treated and control groups. Eight applications were made during 6 weeks in July and August. Results of the tests show that both the oil-based and water-based sprays provided good control against face flies and stable flies for 28 hours and significant reductions of fly populations for 52 or 76 hours following spray application. Both sprays gave near-perfect control of horn flies for 124 hours or longer. The oil-based spray showed greater initial toxic effect than the water-based spray against the face fly but the latter demonstrated a more lasting residual effect. Significant reductions in fly populations were noted on the untreated control group that was milked in the same barn as the treated cows, but in a separate section. The groups were grazed in separate pastures.

Chemical control of Eremophilla mitchellii

Experiments to test the effectiveness of the butoxyethanol ester of 2,4,5-trichlorophenoxyacetic acid on seedling growth and regrowth from old root-stocks of Eremophila mitchellii Benth. were conducted in two localities in south-western Queensland. The treatments were applied during April, May, July, and October 1963, as both water and diesel distillate based emulsions. Phthalic acid and dimethyl phthalate were added to half of the water and half of the diesel treatments respectively, to determine whether either of these chemicals would enhance the effect of the hormone. At no time of application was any water based treatment effective, but the hormone in diesel distillate was effective at all times of the year. A high percentage kill of E. mitchellii was obtained with 0.5 and 1.0 per cent 2,4,5-T in diesel distillate, except on plants having a basal diameter greater than 3 inches. The addition of dimethyl phthalate to the oil-based sprays gave a quicker initial effect, but did not increase the final percentage kill. Diesel distillate alone and in combination with dimethyl phthalate, killed some of the smaller plants, but was ineffective on the larger timber sprayed. At the higher concentrations of 2,4,5-T in diesel distillate, large plants were killed, provided complete wetting of the base of the stem was achieved.

Insecticide Tests on the Douglas-Fir Cone Midge, Contarinia oregonensis Foote

AbstractThree insecticides — lindane, dieldrin, and Sevin — were tested for control of the Douglas-fir cone midge, Contarinia oregonensis Foote (Diptera: Cecidomyiidae). They were applied to infested duff samples at the rate of 1.5 pounds of insecticide in 15 gallons of diesel oil per acre. Lindane was the most effective, causing a 98.5% reduction in the number of midges emerging from the duff. Dieldrin also caused a significant reduction in emergence, but Sevin was no more effective than diesel oil alone.The results of this test suggest that oil-based sprays applied to the duff before the cone midges emerge might give satisfactory control more consistently than the water-based sprays which are usually applied to the trees. The test procedure would avoid the timing and formulation problems involved in treating developing cones on the trees.