Agronomy and Crop Sciences Commons^™

In-Field Optimization Of Soil Water Parameters For Irrigation Scheduling, Ishani Lal

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Several precision technologies are being developed to assist farmers in informed irrigation decision-making. These technologies aim to enhance irrigation water efficiency, check overirrigation, boost crop water productivity, and promote the sustainable utilization of water resources. We hypothesize that soil moisture parameters used in irrigation decision tools need to be validated to best represent the correct state of soil moisture in the field. This is an important factor that affects the accuracy of the irrigation recommendations forecasted by the decision support tools. In this research, we evaluated different methods of estimating field capacity (FC) and wilting point (WP) to optimize soil …

Irrigation Increases On-Farm Soybean Yields In Water-Limited Environments Without A Trade-Off In Seed Protein Concentration, Walter D. Carciochi, Patricio Grassini, Seth Naeve, James E. Specht, Mitiku Mamo, Ron Seymour, Aaron Nygren, Nathan Mueller, Sarah Sivits, Christopher A. Proctor, Jenny Rees, Todd Whitney, N. Cafaro La Menza

Department of Agronomy and Horticulture: Faculty Publications

Context or problem: A trade-off between seed protein concentration (SPC) and yield has been reported for soybean. Therefore, assessing management practices that can nullify this trade-off is relevant to avoid further declines in SPC in the future as yield continues to increase. While the positive effect of irrigation on yield is well documented, only a few studies have assessed the impact of irrigation on SPC, showing conflicting results.

Objective or research question: The objective was to determine if the trade-off between seed yield and SPC persists when irrigation is applied and how management, soil, and weather factors influence the trade-off. …

Evaluation Of Soil Moisture Sensing Technologies In Silt Loam And Loamy Sand Soils: Assessment Of Performance, Temperature Sensitivity, And Site- And Sensor-Specific Calibration Functions, K. Sharma, Sibel Irmak, M. S. Kukal, M. C. Vuran, Amit J. Jhala, Xia Qiao

Department of Agronomy and Horticulture: Faculty Publications

Reliable soil moisture information is vital for optimal irrigation management, farm-level agronomic decision-making, hydrologic studies, and cropping systems modeling. A wide range of soil moisture sensing technologies is commercially available, but their performance must be evaluated for diverse conditions of use. In this research, we investigated nine soil moisture sensors based on time-domain reflectometry, capacitance, and electrical resistance principles in production field conditions with two installation orientations, i.e., vertical (V) and horizontal (H), in two soils (silt loam and loamy sand) and two growing seasons (2017 and 2018). Performance parameters deduced from the 2017 datasets revealed that sensor type and …

Effects Of Different Water And Nitrogen Regimens On Yield Of Winter Wheat Produced In Nebraska, Joseph Emory Davis

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Wheat is the 3rd most prominent crop in the USA and approximately 50% is exported annually. Nebraska wheat production is 11^th in the country, and it plays a major role in the state's agricultural economy, especially in western NE. Generally, wheat is grown under dryland conditions and the region grows much more wheat on unirrigated land than it does on irrigated. However, deficit irrigation has shown great value in producing high yielding wheat with much less water than needed for other crops. Finding new ways to leverage irrigation in wheat production may help address the need to produce food …

Benchmarking Irrigation Water Use In Producer Fields In The Us Central Great Plains, Katherine E. B. Gibson, Justin E. Gibson, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Efficient use of freshwater resources is necessary to balance food production and long-term sustainability of irrigated agricultural systems. Here we developed a framework to benchmark irrigation water use relative to crop yield for individual fields based on site-specific weather and soil. Subsequently, we used the framework to diagnose on-farm irrigation management, in relation to crop production, in maize and soybean producer fields in Nebraska (USA).We found actual irrigation to be similar to estimated irrigation water requirement in about half of the fields (i.e. small water surplus). Remarkably, these fields attained yields similar to fields where actual irrigation exceeded water requirements …

Assessing Explanatory Factors For Variation In On-Farm Irrigation In Us Maize-Soybean Systems, Katherine E.B. Gibson, Haishun S. Yang, Trenton E. Franz, Dean E. Eisenhauer, John B. Gates, Paolo Nasta, Bhupinder S. Farmaha, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Irrigation exhibits large variation across producer fields, even within same region and year. A knowledge gap exists relative to factors that explain this variation, in part due to lack of availability of high-quality irrigation data from multiple field-years. This study assessed sources of variation in irrigation using a large database collected during 9 years (2005–2013) from ca. 1400 maize and soybean producer fields in Nebraska, central USA (total of 12,750 field-year observations). The study area is representative of ca. 4.5 million ha of irrigated land sown with maize and soybean. Influence of biophysical (weather, soil, and crop type) and behavioral …

Long-Term Winter Wheat (Triticum Aestivum L.) Seasonal Irrigation Amount, Evapotranspiration, Yield, And Water Productivity Under Semiarid Climate, Koffi Djaman, Michael O'Neill, Curtis K. Owen, Daniel Smeal, Margaret West, Dallen Begay, Samuel Allen, Komlan Koudahe, Suat Irmak, Kevin Lombard

Department of Agronomy and Horticulture: Faculty Publications

A long-term field experiment was conducted from 2002 to 2014 for the evaluation of yield and water productivity of three winter wheat varieties—Kharkof, Scout 66, and TAM107—under sprinkler irrigation at New Mexico State University Agricultural Science Center at Farmington, NM. Winter wheat daily evapotranspiration was estimated following the United Nations Food and Agriculture Organization FAO crop coefficient approach (ETc = Kc ETo), and crop water use efficiency (CWUE), evapotranspiration water use efficiency (ETWUE), and irrigation water use efficiency (IWUE) were estimated for each growing season. There was inter-annual variation in seasonal precipitation and irrigation amounts. Seasonal irrigation amounts varied from …

Empowerment And Tech Adoption: Introducing The Treadle Pump Triggers Farmers’ Innovation In Eastern Ethiopia, Shimelis Beyene, Teshome H. Regassa, Belaineh Legesse, Martha Mamo, Tsegaye Tadesse

Department of Agronomy and Horticulture: Faculty Publications

In 2013, thirty-eight treadle pumps (TPs) were installed as low-cost technology introduction for small-scale irrigation in eastern Ethiopia. This pilot project also trained six farmers on tube well excavation, as well as the installation and maintenance of pumps. In June 2015, researchers visited nine of the thirty-eight TP villages and found only two TPs functioning as originally installed. The rest were replaced with a new technology developed by the trained farmers. Farmers, empowered by training, gained more control in developing technology options tailored to local needs and conditions of their communities. Adopters of the new technology stated that the limited …

Nitrogen And Water Effects On Canopy Sensor Measurements For Site-Specific Management Of Crops, Nicholas C. Ward

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Water and nitrogen (N) are undoubtedly the two largest agricultural inputs globally. Coupled with advances in site-specific management technology their integration into production agriculture will allow for the most efficient use these crop input resources. Active canopy sensors offer the ability to measure biophysical plant traits rapidly and make assessments about plant status. Specifically, optical sensor measurements of light reflectance assess plant N status allowing for in-season and on-the-go N recommendations and applications; while infrared thermometers (IRT) measurement of canopy temperature can be used a tool for irrigation management. To evaluate how these technologies work among different plant stress environments …

Soil And Crop Response To Stover Removal From Rainfed And Irrigated Corn, Ian Kenney, Humberto Blanco-Canqui, Deann R. Presley, Charles W. Rice, Keith Janssen, Brian Olson

Department of Agronomy and Horticulture: Faculty Publications

Excessive corn (Zea mays L.) stover removal for biofuel and other uses may adversely impact soil and crop production. We assessed the effects of stover removal at 0, 25, 50, 75, and 100% from continuous corn on water erosion, corn yield, and related soil properties during a 3-year study under irrigated and no-tillage management practice on a Ulysses silt loam at Colby, irrigated and strip till management practice on a Hugoton loam at Hugoton, and rainfed and no-tillage management practice on a Woodson silt loam at Ottawa in Kansas, USA. The slope of each soil was <1%. One year after removal, complete (100%) stover removal resulted in increased losses of sediment by 0.36–0.47 Mg ha-1 at the irrigated sites, but, at the rainfed site, removal at rates as low as 50% resulted in increased sediment loss by 0.30 Mg ha-1 and sediment-associated carbon (C) by 0.29 kg ha-1. Complete stover removal reduced wet aggregate stability of the soil at the irrigated sites in the first year after removal, but, at the rainfed site, wet aggregate stability was reduced in all years. Stover removal at rates ≥ 50%resulted in reduced soil water content, increased soil temperature in summer by 3.5–6.8 °C, and reduced tem-perature in winter by about 0.5 °C. Soil C pool tended to decrease and crop yields tended to increase with an increase in stover removal, but 3 years after removal, differences were not significant. Overall, stover removal at rates ≥50% may enhance grain yield but may increase risks of water erosion and negatively affect soil water and temperature regimes in this region.

Drivers Of Spatial And Temporal Variation In Soybean Yield And Irrigation Requirements In The Western Us Corn Belt, Patricio Grassini, Jessica A. Torrion, Kenneth Cassman, Haishun Yang, James Specht

Department of Agronomy and Horticulture: Faculty Publications

Both rainfed and irrigated soybean production are important in Nebraska (western US Corn Belt), accounting for a respective 48 and 52% of the state’s soybean production of 7 Mt on a respective 55 and 45% share of the state soybean area of 1.9 Mha. To date, no assessment of factors that may account for regional and inter-annual variation in yield and irrigation amount has been performed. To accomplish that objective, we evaluated a database containing on-farm field yields and total irrigation amount used in those fields. These data have been collected annually from ca. 1000 soybean fields in six regions …

Bionomics Of Insects Associated With Corn In The Nebraska Sandhills, J. L. Wedberg, J. B. Campbell, T. J. Helms

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Investigations were conducted in the Nebraska Sandhills to determine the impact of transition from grassland to irrigated corn on selected insect species, to identify indigenous species that may be economically important to corn production, and to provide a point of reference for future development of pest management programs for irrigated corn.

Cultural Practices For Seed Production From Established Stands Of Western Wheatgrass, D. E. Smika, L. C. Newell

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Fertilization and irrigation requirements and aftermath removal practices for maximum seed production from solid stand western wheatgrass were studied for three years near Oakley, Kansas. Conclusions from this study indicate that to obtain maximum quantity of highest quality western wheatgrass seed from established stands, the grass must be fertilized in the fall with at least 80 pounds of nitrogen per acre. Irrigation with sufficient water to fill the root zone in either the fall or early spring and again when the grass is in " boot" or heading is necessary. The practice of removing the aftermath following harvest by mowing …

Growing Proso In Nebraska, P. H. Grabouski

Nebraska Agricultural Experiment Station: Historical Circulars

Proso, sometimes called "hog millet," is receiving attention in the Nebraska Panhandle as a dryland grain crop because of acreage restrictions and limited crop alternatives.

Irrigation And Fertilization Practices For Seed Production From Established Stands Of Side-Oats Grama, D. E. Smika, L. C. Newell

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The objectives of this study of grass seed production were to determine the response of an established stand of a warm-season grass to irrigation and fertilizer practices with regard to the specific practices needed to produce maximum quantity of adequate quality seed per acre. Side-oats grama was chosen for the study because of the availability of adapted varieties.

Performance Of Alfalfas Under Five Management Systems, W. R. Kehr, E. C. Conard, M. A. Alexander, F. G. Owen

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This bulletin reports stands, forage yields, and other agronomic data on alfalfas of diverse origin or type tested under five management systems at Lincoln, Nebraska. Narrow-crowned and broad-crowned types were tested. The management systems involved non-irrigated alfalfa-bromegrass tests (a) continuously grazed with steers, (b) cut for hay, and (c) rotationally grazed with sheep; an irrigated alfalfa-bromegrass test rotationally grazed with dairy cattle; and irrigated tests of alfalfas in pure stands cut for hay.

Field Bean Production Under Irrigation In Nebraska, F. V. Pumphrey

Nebraska Agricultural Experiment Station: Historical Circulars

The purpose of this bulletin is to bring together the latest information available on the production of dry edible beans under irrigation in Nebraska. Cultural practices and disease control are stressed, but included are items on marketing, cleaning, and the use of by-products - straw and cull beans.

Aircraft In Agriculture, N. E. Shafer, J. D. Furrer, J. W. Lomax

Nebraska Agricultural Experiment Station: Historical Circulars

Airplanes were first used in agriculture shortly after the close of World War I. They proved valuable for locating mosquito breeding areas, for forest fire patrol work, as an aid in locating outlaw cotton fields in the campaign against pink bollworm, and for surveying damage caused in large forested areas by the spruce budworm.

Safflower Production In The Western Part Of The Northern Great Plains, C. E. Classen

Nebraska Agricultural Experiment Station: Historical Circulars

Recent development of new varieties with seeds averaging more than 30 per cent oil give safflower a good chance of becoming an important oil seed crop in the United States. It is the purpose of this circular to acquaint farmers with the crop and to outline the most promising production practices for those who undertake its production in the western part of the northern Great Plains.

Safflower Production In The Western Part Of The Northern Great Plains, C. E. Classen

Nebraska Agricultural Experiment Station: Historical Circulars

Recent development of new varieties with seeds averaging more than 30 per cent oil give safflower a good chance of becoming an important oil seed crop in the United States. It is the purpose of this circular to acquaint farmers with the crop and to outline the most promising production practices for those who undertake its production in the western part of the northern Great Plains.

The Scottsbluff Pinto Bean, J. H. Jensen

Nebraska Agricultural Experiment Station: Historical Circulars

Scottsbluff Pinto is the name of a new variety of pinto field bean being released this year by the Nebraska Agricultural Experiment Station. The new bean variety is a selection from a cross between Great Northern and the common pinto bean. In a bean-breeding program conducted for the past several years by the Department of Plant Pathology, attempts have been made to obtain improved varieties of both field and garden beans for Nebraska. Although the breeding program was primarily concerned with the development of disease-resistant varieties, it was observed that Scottsbluff Pinto, possessing no notable disease resistance, has been outstanding …