The study was conducted at the University of Nebraska Pesticide Application and Technology Laboratory in North Platte, Nebraska in July 2015. Two application volume rates (100 and 200 l · ha−1) and three nozzle types (XR, AIXR, TTI) were selected at two flow rates (0.8 and 1.6 l · min−1) and at a single application speed of 7.7 km · h−1. Each collector type [Mylar washed (MW), Mylar image analysis (MIA), water-sensitive paper (WSP), and Kromekote (KK)] was arranged in a randomized complete block design. Each nozzle treatment was replicated twice, providing six cards of each collector type for each nozzle treatment. A water + 0.4% v/v Rhodamine WT spray solution was applied, given the fluorescent and visible qualities of Rhodamine, which allows it to be applied over all the collector types. MW had the highest coverage at 18.3% across nozzle type, followed by WSP at 18%, KK at 12% and lastly by MIA at 4%. MW resulted in a 58% increase in coverage, WSP in a 56% increase, and KK only an increase of 39% when the volume rate was doubled from 100 l · ha−1 to 200 l · ha−1 across nozzle type. MW coverage was similar to KK for half of the nozzles (XR 11002, XR 11004, AIXR 11002). Droplet number density fixed effects were all significant for nozzle type and collector type (p < 0.001) as was the interaction of nozzle type and collector type (p < 0.001). Results from this study suggest a strong correlation to data produced with WSP and MW collectors, as there was full agreement between both types except for the TTI 11004. Using both collector types in the same study would allow for a visual understanding of the distribution of the spray, while also giving an idea of the concentration of that distribution.
The authors acknowledge the Grains Research and Development Corporation of Australia (GRDC) for their support of this work through the project UWA 00165 titled “Options for improved insecticide and fungicide use and canopy penetration in cereals and canola.” The authors also would like to thank John Moore of the Department of Agriculture and Food WA for his support of travel in this study.
The authors acknowledge the Grains Research and Development Corporation of Australia (GRDC) for their support of this work through the project UWA 00165 titled “Options for improved insecticide and fungicide use and canopy penetration in cereals and canola.”
The authors have declared that no conflict of interests exist.
ASABE/ANSI. 2018. Spray Nozzle Classification by Droplet Spectra. Standard 572.2 American Society of Agricultural and Biological Engineers, St. Joseph, MI.
Creech C.F. 2015. Herbicide application technology impacts on herbicide spray characteristics and performance. Ph.D. Dissertation. University of Nebraska, Lincoln, NE. Available on: http://search.proquest.com/doc... [Accessed: 30 June, 2017].
Derksen R.C., Zhu H., Ozkan H.E., Hammond R.B., Dorrance A.E., Spongberg A.L. 2008. Determining the influence of spray quality, nozzle type, spray volume, and air-assisted application strategies on deposition of pesticides in soybean canopy. Transactions of ASAE 51: 1529-1537.
Derksen R.D., Ozkan H.E., Paul P.A., Zhu H. 2014. Plant canopy characteristics effect on spray deposition. Aspects of Applied Biology 122: 227−234.
Dorr G.J., Kempthorne D.M., Mayo L.C., Forster W.A., Zabkiewicz J.A., McCue S.W., Belward J.A., Turner I.W., Hanan J. 2014. Towards a model of spray-canopy interactions: Interception, shatter, bounce and retention of droplets on horizontal leaves. Ecological Modelling 290: 94−101. DOI: https://doi.org/10.1016/j.ecol....
Dorr G.J., Wang S., Mayo L.C., McCue S.W., Forster W.A., Hanan J., He X. 2015. Impaction of spray droplets on leaves: influence of formulation and leaf character on shatter, bounce and adhesion. Experimental Fluids 56 (7): 143. DOI: 10.1007/s00348-015-2012-9.
EPA. 1999. Spray drift on pesticides. EPA Publication No. 735 F99024, United States Environmental Protection Agency, Washington, D.C.
Ferguson J.C., O’Donnell C.C., Chauhan B.S., Adkins S.W., Kruger G.R., Wang R., Urach Ferreira P.H., Hewitt A.J. 2015. Determining the uniformity and consistency of droplet size across spray drift reducing nozzles in a wind tunnel. Crop Protection 76: 1−6. DOI: https://doi.org/10.1016/j.crop....
Ferguson J.C., Chechetto R.G., Hewitt A.J., Chauhan B.S., Adkins S.W., Kruger G.R., O’Donnell C.C. 2016. Assessing the deposition and canopy penetration of nozzles with different spray qualities in an oat (Avena sativa L.) canopy. Crop Protection 81: 14−19. DOI: https://doi.org/10.1016/j.crop....
Forster W.A., Gaskin R.E., Strand T.M., Manktelow D.W.L., van Leeuwen R.M. 2014. Effect of target wettability on spray droplet adhesion, retention, spreading and coverage: artificial collectors versus plant surfaces. New Zealand Plant Protection 67: 284−291. DOI: 10.30843/nzpp.2014.67.5727.
Fritz B.K., Kirk I.W., Hoffmann W.C., Martin D.E., Hofman V.I., Hollingsworth C., McMullen M., Halley S. 2005. Aerial application methods for increasing spray deposition on wheat heads. Applied Engineering in Agriculture 22 (3): 357−364. DOI: 10.13031/2013.20453.
Hanna H.M., Robertson A.E., Carlton M.W., Wolf R.E. 2009. Nozzle and carrier application effects on control of soybean leaf spot diseases. Applied Engineering in Agriculture 25 (1): 5−13. DOI: 10.13031/2013.25424.
Hewitt A.J., Meganasa T. 1993. Droplet distribution densities of a pyrethroid insecticide within grass and maize canopies for the control of Spodoptera exempta larvae. Crop Protection 12 (1): 59−62. DOI: https://doi.org/10.1016/0261-2....
Hewitt A.J. 1997. Spray Drift Task Force study A95-010, miscellaneous study nozzle study. EPA MRID No. 44310401.
Hewitt A.J. 2000. Spray drift: Impact of requirements to protect the environment. Crop Protection 19: 623–627. DOI:10.1016/S0261-2194(00)00082-X.
Higgins A.H. 1967. Spread factors for technical malathion. Journal of Economic Entomology 62: 912−916.
Hill B.D., Inaba J. 1989. Use of water-sensitive paper to monitor the deposition of aerially applied insecticides. Journal of Economic Entomology 82 (3): 974−980. DOI: https://doi.org/10.1093/jee/82....
Hoffmann W.C., Hewitt A.J. 2005. Comparison of three imaging systems for water-sensitive papers. Applied Engineering in Agriculture 21 (6): 961−964. DOI: 10.13031/2013.20026.
Johnstone D.R. 1960. Assessment techniques 2. Photographic paper. CPRU Porton Report No. 177. Mimeographed.
Kenward M.G., Roger J.H. 1997. Small sample inference for fixed effects from restricted maximum likelihood. Biometrics 53 (3): 983−997. DOI: 10.2307/2533558.
Knoche M. 1994. Effect of droplet size and carrier volume on performance of foliage-applied herbicides. Crop Protection 13 (3): 163−178. DOI: 10.1016/0261-2194(94)90075-2.
Lee C.W., Parker J.D., Baldrey D.A.T., Molyneux D.H. 1978. The experimental application of insecticides from a helicopter for the control of riverina populations of Glossina tachinoides in West Africa. II Calibration of Equipment and Insecticide Dispersal. Pesticide Application News Sheets 24: 404−422.
Osteen C.D., Fernandez-Cornejo J. 2013. Economic and policy issues of U.S. agricultural pesticide use and trends. Pest Management Science 69: 1001−1025.
Rasband W.S. 2008. ImageJ, U.S. National Institutes of Health, Bethesda, Maryland, USA. 1997–2008.
Sidak Z. 1967. Rectangular confidence regions for the means of multivariate normal distributions. Journal of the American Statistical Association 62: 626−633.
Spillman J.J. 1984. Spray impactions, retention and adhesions: An introduction to basic characteristics. Pesticide Science 15: 97–106.
Turner C.R., Huntington K.A. 1970. The use of a water sensitive dye for the detection and assessment of small spray droplets. Journal of Agricultural Engineering Research 15 (4): 385−387. DOI: https://doi.org/10.1016/0021-8....
Uk S., Courshee R.J. 1982. Distribution and likely effectiveness of spray deposits within a cotton canopy from fine ultralowvolume spray applied by aircraft. Pesticide Science 13 (5): 529−536. DOI: 10.1002/ps.2780130511.
Wolf R.E., Daggupati N.P. 2009. Nozzle type effect on soybean canopy penetration. Applied Engineering in Agriculture 25 (1): 23−30.
Wolf T.M., Harrison S.K., Hall F.R., Cooper J. 2000. Optimizing postemergence herbicide deposition and efficacy through application variables in no-till systems. Weed Science 48 (6): 761−768.
Zhu H., Dorner J.W., Rowland D.L., Derksen R.C., Ozkan H.E. 2004. Spray penetration into peanut canopies with hydraulic nozzle tips. Biosystems Engineering 87 (3): 275−283. DOI: 10.1016/j.biosystemseng.2003.11.012.