Agronomy and Horticulture Department

 

Date of this Version

5-6-2013

Comments

A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Agronomy, Under the Supervision of Professor Greg R. Kruger. Lincoln, Nebraska: March, 2013

Copyright (c) 2013 J. Connor Ferguson

Abstract

An Ultra-Low Volume (ULV) sprayer was developed to decrease carrier volume required for pesticide applications in row and turfgrass cropping systems. The ULV sprayer can make spray applications at or below 19 L ha-1, which is far lower than a conventional sprayer in row crop or turfgrass production systems. Field studies were conducted at the University of Nebraska West Central Research and Extension Center Dryland Farm near North Platte, NE and the John Seaton Anderson Turfgrass Research Facility near Mead, NE to compare the ULV sprayer to a conventional sprayer. Studies were conducted to compare the two sprayers with herbicide applications, fungicide applications, and foliar fertilizer applications.

The row crop studies were applied over plots planted to six different species. Plant species used were non-glyphosate-resistant corn (Zea mays L.), non-corn glyphosate-resistant soybeans (Glycine max (L.) Merr.), amaranth (Amaranthus hypochondriacus L.), quinoa (Chenopodium quinoa Willd.), velvetleaf (Abutilon theophrasti Medik.), and green foxtail (Setaria viridis (L.) Beauv). Each of these species were harvested and dried to compare dry weight reductions from the herbicide applications. The row crop studies were conducted in the summer of 2011 and the summer of 2012. The row crop studies also compared droplet size and distribution on a laser diffraction instrument to correlate droplet size and efficacy in the comparison of the two sprayers. In general the ULV sprayer had a different droplet spectrum from the conventional sprayer, but differences in the droplet size did not reveal a difference in the dry weight reductions across the row crop studies over both years.

The turfgrass studies were conducted in one of three different turfgrass systems: a mixed stand of Kentucky bluegrass (Poa pratensis L.) and perennial ryegrass (Lolium perenne L.); a uniform stand of tall fescue (Festuca arundinacea Schreb.); or a creeping bentgrass ‘L-93’ (Agrostis stolonifera L.) system managed to fairway height. The turfgrass studies were conducted in the spring and summer of 2012. Differences were not observed between the two sprayers across all of the turfgrass studies.

The ULV sprayer appears to be a useful option for a variety of spray applications in row crop and turfgrass production systems.

Adviser: Greg R. Kruger