Life Sciences Commons^™

Using Adults To Monitor Rnai Susceptibility Of Western Corn Rootworm, Diabrotica Virgifera Virgifera Leconte, Field Populations, Matthew Welter

Department of Entomology: Dissertations, Theses, and Student Research

The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is the most damaging corn pest in the U.S. Corn Belt, costing producers over $1 billion annually in control and damage costs. Currently, corn producers rely on three control strategies for WCR management: crop rotation, chemical insecticides, and transgenic corn expressing Bacillus thuringiensis Berliner (Bt) proteins. Populations of WCR have evolved resistance to all of these tactics, limiting effective control strategies for producers. RNA interference (RNAi), is the newest mode of action developed for WCR management. In July 2017, the first RNAi plant-incorporated protectant (PIP) corn product was approved for production …

Integration Of Cover Crops Into Midwest Corn-Soybean Cropping Systems And Potential For Weed Suppression, Joshua S. Wehrbein

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

Cover crops have potential to provide benefits to agricultural systems, such as improved soil productivity, nutrient scavenging, weed suppression, and livestock forage. There are several challenges associated with cover crop integration into traditional Midwest corn-soybean cropping systems. One of these challenges is timely establishment in the fall, which is limited by the relatively late harvest of corn and soybean. Cover crop effectiveness is related to the amount of biomass produced, thus maximizing the growth period in the fall is desired. To address this challenge, we evaluated the potential to utilize early-season soybean maturity groups (MGs) to allow for earlier soybean …

Arkansas Corn And Grain Sorghum Performance Tests 2019, J. F. Carlin, R. D. Bond, J. A. Still

Arkansas Agricultural Experiment Station Research Series

Corn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers. The 2019 corn performance tests contained 74 hybrids and were conducted at the Northeast Research and Extension Center (NEREC) at Keiser, the Lon Mann Cotton Research Station (LMCRS) near Marianna, the Bell Farming Company near Des Arc, the Rohwer Research Station (RRS) near Rohwer and the Rice Research and Extension Center (RREC) near Stuttgart. The 2019 …

Statistical And Machine Learning Methods Evaluated For Incorporating Soil And Weather Into Corn Nitrogen Recommendations, Curtis J. Ransom, Newell R. Kitchen, James J. Camberato, Paul R. Carter, Richard B. Ferguson, Fabián G. Fernández, David W. Franzen, Carrie A. M. Laboski, D. Brenton Myers, Emerson D. Nafziger, John E. Sawyer, John F. Shanahan

John E. Sawyer

Nitrogen (N) fertilizer recommendation tools could be improved for estimating corn (Zea mays L.) N needs by incorporating site-specific soil and weather information. However, an evaluation of analytical methods is needed to determine the success of incorporating this information. The objectives of this research were to evaluate statistical and machine learning (ML) algorithms for utilizing soil and weather information for improving corn N recommendation tools. Eight algorithms [stepwise, ridge regression, least absolute shrinkage and selection operator (Lasso), elastic net regression, principal component regression (PCR), partial least squares regression (PLSR), decision tree, and random forest] were evaluated using a dataset …

Divergence Of Usda Trade Payments For Corn, Soybean, And Wheat Producers And ‘Nowcasts’ Of Tariff Impacts, Matthew Elliott, Lisa Elliott

Matthew Elliott

No abstract provided.

Factors Influencing The Spatial Distribution Of Southern Rust In Corn, Justin Bailey

Graduate Theses and Dissertations

Southern rust caused by the fungus Puccinia polysora (Underwood) is the most economically important foliar disease in corn (Zea mays) (Linnaeus) (Cyperales: Poaceae)) for Arkansas. The objective of this work was to determine distribution of southern rust in corn and to determine factors that may control its distribution.

During the 2017 and 2018 season, seven corn fields in Arkansas were rated for southern rust. After disease confirmation, fields were marked with GPS sample point locations in a grid pattern across the entire field. Ratings for disease severity were taken below, at, and above the ear leaf at each point every …

Utilizing Growing Degree Days For Corn Production, Dexton Lake, Matt Yost, Clark Israelsen

All Current Publications

This fact sheet explains the concepts and formulas in determining growing degree days.

Development Of A Nitrogen Recommendation Tool For Corn Considering Static And Dynamic Variables, Laila A. Puntel, Agustin Pagani, Sotirios V. Archontoulis

Department of Agronomy and Horticulture: Faculty Publications

Many soil and weather variables can affect the economical optimum nitrogen (N) rate (EONR) for maize. We classified 54 potential factors as dynamic (change rapidly over time, e.g. soil water) and static (change slowly over time, e.g. soil organic matter) and explored their relative importance on EONR and yield prediction by analyzing a dataset with 51 N trials from Central-West region of Argentina. Across trials, the average EONR was 113 ± 83 kg N ha⁻¹ and the average optimum yield was 12.3 ± 2.2 Mg ha⁻¹, which is roughly 50% higher than the current N rates used …

Evaluation Of Stabilized Fertilizer And Crop Canopy Sensors As Next-Generation Nitrogen Management Technologies In Irrigated Corn, Leonardo Mendes Bastos

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

Nitrogen (N) is often the most limiting nutrient to corn. Once applied to the field, N can be lost through different pathways, which contributes to low N use efficiency (NUE) by plants. Increases in NUE and decreases in N losses can be potentially achieved by using management options that allow a better synchrony between N supply and demand, such as stabilized fertilizers, and spatially-variable sensor-derived in-season N application. Three studies were conducted in order to assess the effects of different stabilized fertilizers and crop canopy sensors on irrigated corn yield. The first study evaluated the effect of urease inhibitor on …

Vermont Organic Silage Corn Performance Trial, Heather Darby, Sara Ziegler, John Bruce, Ivy Krezinski, Rory Malone

Northwest Crops & Soils Program

The University of Vermont Extension Northwest Crops and Soils Program conducted an organic silage corn variety trial in 2019 to provide unbiased performance comparisons of commercially available varieties. With the expansion of the organic dairy industry in our region there is increased interest in organic corn silage production. To determine varieties that are best suited to this production system and our region’s climate, we evaluated 11 commercially available organic corn silage varieties. It is important to remember that the data presented are from a replicated research trial from only one location in Vermont and represent only one season. Crop performance …

Long Season Corn Silage Performance Trials Summary, Heather Darby

Northwest Crops & Soils Program

Long season corn (96-110 day relative maturity) silage hybrids in Alburgh, VT

Planting Date: 05-13-19

Harvest Date: 10-02-19

Short Season Corn Silage Performance Trials Summary, Heather Darby

Northwest Crops & Soils Program

Short season corn (85-95 day relative maturity) silage hybrids in Alburgh, VT

Planting Date: 05-22-19

Harvest Date: 09-25-19

Vermont Flint And Dent Corn Performance Trial, Heather Darby, Sara Ziegler, John Bruce, Ivy Krezinski, Rory Malone

Northwest Crops & Soils Program

In the northeast there is a strong demand from consumers to have access to a wide range of locally produced food products. This demand creates opportunities for specialty value-added markets and crops to emerge. One market that has been gaining popularity and expanding recently in the northeast is the specialty corn market. Flint corn has very hard starch and can be ground and used in tortillas, tamales, corn meal, grits, and other products. Flint has a high proportion of hard starch in the kernel that produces a coarse meal. This is different than a soft-starch flour corn that, when ground, …

Vermont Non-Gmo Corn Silage Performance Trial, Heather Darby, Sara Ziegler, John Bruce, Ivy Luke, Rory Malone

Northwest Crops & Soils Program

In 2019, the University of Vermont Extension Northwest Crops and Soils Program evaluated yield and quality of 10 non-GMO corn silage varieties at Borderview Research Farm, Alburgh, VT. A non-GMO milk market has prompted some dairy farmers to start growing corn silage that has not been genetically modified. Conventional farmers have countless corn silage varieties available supported by performance data and trait information. To successfully transition to growing non-GMO corn, farmers are looking for more information on non-GMO varieties that are available and perform well in our region. While the information presented can begin to describe the yield and quality …

New York And Vermont Corn Silage Hybrid Evaluation Program, Joseph Lawrence, Allison Kerwin, Thomas Overton, Heather Darby

Northwest Crops & Soils Program

In 2019, the corn silage hybrid evaluation program received 75 entries from 14 seed brands. Hybrid evaluation at multiple environments helps in decision making and expands the reach of this type of data to more farmers. With this in mind Cornell, UVM, and seed companies collaborate to provide this robust evaluation. Hybrids were either entered into the 80-95 day relative maturity (RM) group (Early-Mid) and were tested at two locations in NY (n = 26; Hu-Lane Farm in Albion and the Willsboro Research Farm in Willsboro) and one location in VT (n = 26; Borderview Farm in Alburgh) …

Syngenta Silage Corn Variety Trial, Heather Darby, Rory Malone, Lindsey Ruhl, Sara Ziegler

Northwest Crops & Soils Program

The University of Vermont Extension Northwest Crops and Soils Program conducted a variety trial of silage corn from Syngenta AG (Greensboro, NC) to provide unbiased performance comparison of eight commercially available varieties, and to determine varieties best suited to this production system and local climate. It is important to remember that the data presented are from a replicated research trial from only one location in Vermont and represent only one season. Crop performance data from additional tests in different locations and over several years should be compared before making varietal selections.

Impacts Of Small Intestinal Enzyme Activity And Varying Corn Grain Processing Types On Feeding Behavior, And Growth Performance Of Finishing Beef Steers, Wyatt Smith

Electronic Theses and Dissertations

The objective of this study was to quantify the differences in activity of jejunal maltase and isomaltase between 2 groups of steers with average dry matter intake (DMI) and differing average daily gain (ADG). Dry matter intake and ADG were measured in crossbred steers (n = 69). Jejunal mucosal samples were collected from 8 steers with the greatest (high) or least (low) ADG and average DMI (± 0.55 standard deviation). Homogenates of jejunal mucosa were incubated with increasing amounts of maltose and isomaltose to determine the disaccharidase kinetics. Neither the Km of isomaltase (P = 0.15) or maltase (P = …

Wheat Stem Maggot (Diptera: Chloropidae): An Emerging Pest Of Cover Crop To Corn Transition Systems, Gabriela Inveninato Carmona, Jennifer M. Rees, Ronald C. Seymour, Robert J. Wright, Anthony J. Mcmechan

Department of Entomology: Faculty Publications

The wheat stem maggot (Meromyza americana Fitch) (WSM) is a minor pest of wheat, rye, and other grasses. In 2017, growers in Nebraska reported dead center whorls and excessive tillering in early-season cornfields that followed wheat or rye terminated after planting corn. A survey was conducted to evaluate the risk factors for this insect in cover crop to corn transition systems. In each field, management practices and the percentage of injured plants were recorded. Symptomatic corn plants were collected from each field and dissected to determine larval and plant characteristics. In a few cases, small patches of a field …

Metabolizable Energy Determination In Broiler Chickens, Andrew E. Dunaway

Theses and Dissertations--Animal and Food Sciences

Feed accounts for the highest cost associated in poultry production, with energy-containing feedstuffs being the most expensive portion of the cost of feeding. The increasing demand for poultry meat gives reason to determine accurate apparent metabolizable energy (AME) values for various feedstuff through measuring energy utilization in the birds. The adaptation length of birds fed an experimental diet may affect the determined AME value due to the diet matrix and physiochemical properties of the feedstuff. Therefore, the objective of this thesis was to evaluate a select group of energy-containing feedstuff with different diets and with factors such as coccidia challenge …

Wildlife Damage To Crops Adjacent To A Protected Area In Southeastern Mexico: Farmers’ Perceptions Versus Actual Impact, Gabriel Can-Hernández, Claudia Villanueva-García, Elías José Gordillo-Chávez, Coral Jazvel Pacheco-Figueroa, Elizabeth Pérez-Netzahual, Rodrigo García-Morales

Human–Wildlife Interactions

Human–wildlife conflicts occur when wildlife has an adverse effect on human activities (e.g., predation of livestock, crop raiding). These conflicts are increasing, particularly in areas surrounding natural protected areas, where villagers engage in subsistence agriculture. Crop damage may cause farmers to retaliate and harm wildlife species considered responsible for the damage. Among the factors that determine the intensity of the conflict are the frequency of the damage and the amount of biomass consumed relative to the perceptions, values, and cultural history of the farmers affected. To better understand the conflicts between farmers and wildlife, we compared farmer perceptions of wildlife …

Effect Of Fumonisin-Contaminated Corn On Growth Performance Of 20- To 60-Lb Nursery Pigs, Z. X. Rao, M. D. Tokach, S. S. Dritz, J. C. Woodworth, J. M. Derouchey, R. D. Goodband, H. Calderon Cartagena

Kansas Agricultural Experiment Station Research Reports

This experiment was conducted to determine the effect of feeding fumonisin (FUM) contaminated corn on growth performance of 20- to 60-lb nursery pigs. A total of 350 pigs (241 × 600; DNA, Columbus, NE; initially 19.6 lb) were used. Dietary treatments consisted of FUM-contaminated corn blended with relatively FUM-free corn to provide toxin (FB1 + FB2) of 7.2, 14.7, 21.9, 32.7, and 35.1 ppm. Experimental diets were fed in mash form for 28 d. There were 5 pigs per pen and 14 replicates per treatment. After weaning, pigs were fed common diets for 21 days before the experiment started. Then, …

Statistical And Machine Learning Methods Evaluated For Incorporating Soil And Weather Into Corn Nitrogen Recommendations, Curtis J. Ransom, Newell R. Kitchen, James J. Camberato, Paul R. Carter, Richard B. Ferguson, Fabian G. Fernandez, David W. Franzen, Carrie A. M. Laboski, D. Brenton Myers, Emerson D. Nafziger, John E. Sawyer, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Nitrogen (N) fertilizer recommendation tools could be improved for estimating corn (Zea mays L.) N needs by incorporating site-specific soil and weather information. However, an evaluation of analytical methods is needed to determine the success of incorporating this information. The objectives of this research were to evaluate statistical and machine learning (ML) algorithms for utilizing soil and weather information for improving corn N recommendation tools. Eight algorithms [stepwise, ridge regression, least absolute shrinkage and selection operator (Lasso), elastic net regression, principal component regression (PCR), partial least squares regression (PLSR), decision tree, and random forest] were evaluated using a dataset …

Effects Of Supplementation With Corn Or Dried Distillers Grains On Gains Of Heifer Calves Grazing Smooth Bromegrass Pastures, L. W. Lomas, J. L. Moyer

Kansas Agricultural Experiment Station Research Reports

A total of 150 heifer calves grazing smooth bromegrass pastures were used to compare supplementation with 0.5% of body weight per head daily of corn or dried distillers grains (DDG) in 2014, 2015, 2016, 2017, and 2018. Daily gains of heifers supplement­ed with corn or DDG were similar (P > 0.05) in all years except 2018, when heifers supplemented with DDG had greater (P < 0.05) gains than those supplemented with corn.

Southeast Kansas Crop Production Summary – 2018, G. F. Sassenrath, L. Mengarelli, J. Lingenfelser, X. Lin

Kansas Agricultural Experiment Station Research Reports

This is a summary of the crop production conditions in southeast Kansas in 2018, and the results of the variety testing for corn, soybean, sorghum, sunflower, and wheat.

Tillage Study For Corn And Soybeans: Comparing Vertical, Deep, And No-Tillage, E. A. Adee

Kansas Agricultural Experiment Station Research Reports

Trends from a tillage study conducted since 2011 have shown no clear differences between tillage systems for either corn or soybeans in lighter soils under irrigation. One out of seven years has shown a yield advantage for either corn or soybeans for any tillage system, which appears to be related to environmental conditions experienced during the season.

Changes In Soil Nitrate And Ammonium During The Corn Growing Season As Affected By Nitrification Inhibitors, F. D. Hansel, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

Nitrification inhibitors (NI) are used to delay the nitrification process, increasing nitrogen fertilization efficiency. The objective of this study was to evaluate the effect of NI on soil nitrate (NO₃-N) and ammonium (NH₄-N) content throughout the growing season for corn. The study was conducted at four locations (Manhattan, Scandia, Rossville, and Ashland, KS) during the 2017 and 2018 crop seasons. Most of the NI effects on soil NH₄-N and NO₃-N were observed early in the season and when the higher nitrogen (N) fertilizer rate was used. An increase in NO₃-N …

Kansas Field Research 2019

Kansas Agricultural Experiment Station Research Reports

Research from Kansas State University experiment fields on crop varieties, tillage, irrigation, weed management, and fertilizers.

Effects Of Grinding Corn With Different Moisture Concentrations On Subsequent Particle Size And Flowability Characteristics, M. B. Braun, K. M. Dunmire, C. E. Evans, C. R. Stark, C. B. Paulk

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to determine the effects of whole corn moisture and hammermill screen size on subsequent ground corn moisture, particle size, and flow- ability. Whole yellow dent #2 corn was used for this experiment. Treatments were arranged as a 2 × 2 factorial design with two moisture concentrations (as-received and high) each ground using 2 hammermill screen sizes (1/8 and 1/4 in). Corn was ground using a laboratory scale 1.5 HP Bliss Hammermill (Model 6K630B) at 3 separate time points to create 3 replications per treatment. Increasing initial whole corn moisture was accomplished by adding 5% …

Pre-Plant Nitrogen Rate And Application Method And Side-Dress Nitrogen Rate Effects On Corn Grown No-Till On A Claypan Soil, D. W. Sweeney, D. Ruiz-Diaz

Kansas Agricultural Experiment Station Research Reports

Corn yield in 2018 was increased by about 5 bu/a with knife application of pre-plant nitrogen (N) fertilizer compared with broadcast application. Fertilizing with increasing rates of N applied pre-plant, at side-dress, or both had little effect on yield or yield components of corn in 2018.

Alternative Cropping Systems With Limited Irrigation, A. Schlegel, D. Bond

Kansas Agricultural Experiment Station Research Reports

A limited irrigation study involving four cropping systems and evaluating four crop rotations was initiated at the Southwest Research-Extension Center near Tribune, KS, in 2012. The cropping systems were two annual systems (continuous corn [C-C] and continuous grain sorghum [GS-GS]) and two 2-year systems (corn- grain sorghum [C-GS] and corn-winter wheat [C-W]). In 2018, corn yields were similar for all rotations, although averaged across the past 6 years, corn yields were greater following wheat than following corn. There were no significant differences in grain sorghum yields in 2018, which was similar to the multi-year average. Wheat yields were near the …