Agronomy and Crop Sciences Commons^™

Transforming Unmanned Aerial Vehicle (Uav) And Multispectral Sensor Into A Practical Decision Support System For Precision Nitrogen Management In Corn, Laura J. Thompson, Laila A. Puntel

Department of Agronomy and Horticulture: Faculty Publications

Determining the optimal nitrogen (N) rate in corn remains a critical issue, mainly due to unaccounted spatial (e.g., soil properties) and temporal (e.g., weather) variability. Unmanned aerial vehicles (UAVs) equipped with multispectral sensors may provide opportunities to improve N management by the timely informing of spatially variable, in-season N applications. Here, we developed a practical decision support system (DSS) to translate spatial field characteristics and normalized difference red edge (NDRE) values into an in-season N application recommendation. On-farm strip-trials were established at three sites over two years to compare farmer’s traditional N management to a split-application N management guided by …

Dicamba Retention In Commercial Sprayers Following Triple Rinse Cleanout Procedures, And Soybean Response To Contamination Concentrations, Frances B. Browne, Xiao Li, Katilyn J. Price, Jianping Wang, Yi Wang, Greg R. Kruger, Jeff Golus, Gabrielle De Castro Macedo, Bruno C. Vieira, Tyler Sandlin

Department of Agronomy and Horticulture: Faculty Publications

The commercial launch of dicamba‐tolerant (DT) crops has resulted in increased dicamba usage and a high number of dicamba off‐target movement complaints on sensitive soybeans (Glycine max L.). Dicamba is a synthetic auxin and low dosages as 0.028 g ae ha−1 can induce injury on sensitive soybean. Tank contamination has been identified as one of the sources for unintended sensitive crop exposure. The labels of new dicamba formulations require a triple rinse cleanout procedure following applications. Cleanout efficacy might vary based on the sprayer type and procedure followed. This study was performed to quantify dicamba retention in commercial sprayers and …

Land-Use Type As A Driver Of Large Wildfire Occurrence In The U.S. Great Plains, Victoria M. Donovan, Carissa L. Wonkka, David A. Wedin, Dirac Twidwell

Department of Agronomy and Horticulture: Faculty Publications

Wildfire activity has surged in North America’s temperate grassland biome. Like many biomes, this system has undergone drastic land-use change over the last century; however, how various land-use types contribute to wildfire patterns in grassland systems is unclear. We determine if certain land-use types have a greater propensity for large wildfire in the U.S. Great Plains and how this changes given the percentage of land covered by a given land-use type. Almost 90% of the area burned in the Great Plains occurred in woody and grassland land-use types. Although grassland comprised the greatest area burned by large wildfires, woody vegetation …

Improving On Modis Mcd64a1 Burned Area Estimates In Grassland Systems: A Case Study In Kansas Flint Hills Tall Grass Prairie, Rheinhardt Scholtz, Jayson Prentice, Yao Tang, Dirac Twidwell

Department of Agronomy and Horticulture: Faculty Publications

Uncertainty in satellite-derived burned area estimates are especially high in grassland systems, which are some of the most frequently burned ecosystems in the world. In this study, we compare differences in predicted burned area estimates for a region with the highest fire activity in North America, the Flint Hills of Kansas, USA, using the moderate resolution imaging spectroradiometer (MODIS) MCD64A1 burned area product and a customization of the MODIS MCD64A1 product using a major ground-truthing effort by the Kansas Department of Health and Environment (KDHE-MODIS customization). Local-scale ground-truthing and the KDHE-MODIS product suggests MODIS burned area estimates under predicted fire …

Prediction Strategies For Leveraging Information Of Associated Traits Under Single- And Multi-Trait Approaches In Soybeans, Reyna Persa, Arthur Bernardeli, Diego Jarquin

Department of Agronomy and Horticulture: Faculty Publications

The availability of molecular markers has revolutionized conventional ways to improve genotypes in plant and animal breeding through genome-based predictions. Several models and methods have been developed to leverage the genomic information in the prediction context to allow more efficient ways to screen and select superior genotypes. In plant breeding, usually, grain yield (yield) is the main trait to drive the selection of superior genotypes; however, in many cases, the information of associated traits is also routinely collected and it can potentially be used to enhance the selection. In this research, we considered different prediction strategies to leverage the information …

Overexpression Of Ferulate 5‑Hydroxylase Increases Syringyl Units In Sorghum Bicolor, Hannah M. Tetreault, Tammy Gries, Nathan Palmer, Deanna L. Funnell-Harris, Shirley Sato, Zhengxiang Ge, Gautam Sarath, Scott Sattler

Department of Agronomy and Horticulture: Faculty Publications

Ferulate 5-hydroxylase (F5H) of the monolignol pathway catalyzes the hydroxylation of coniferyl alcohol, coniferaldehyde and ferulic acid to produce 5-hydroxyconiferyl moieties, which lead to the formation of sinapic acid and syringyl (S) lignin monomers. In contrast, guaiacyl (G) lignin, the other major type of lignin monomer, is derived from polymerization of coniferyl alcohol. In this study, the effects of manipulating S-lignin biosynthesis in sorghum (Sorghum bicolor) were evaluated. Overexpression of sorghum F5H (SbF5H), under the control of the CaMV 35S promoter, increased both S-lignin levels and the ratio of S/G lignin, while plant growth and development …

Transformative Education In Agroecology: Student, Teacher, And Client Involvement In Co-Learning, Charles A. Francis, Anna Marie Nicolaysen, Geir Lieblein, Tor Arvid Breland

Department of Agronomy and Horticulture: Faculty Publications

Educational methods have evolved rapidly in agroecology, which is a complex and holistic field without a long history or the formal tradition of any single academic discipline. Definitions of agroecology have evolved from its initial conception as a marriage of agriculture with ecology, to an aggregation of different paths including science, practices, and movements, and recently as a broad appreciation of the ecology of food systems. In contrast with traditional courses that begin with a history of the discipline and review the contributions of early leaders, we have embraced phenomenology to firmly establish roots in students’ learning through their experiences …

Urban Food Sovereignty: Urgent Need For Agroecology And Systems Thinking In A Post-Covid-19 Future, Ali Loker, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

The current COVID-19 pandemic has brought attention to challenges associated with our dominant industrial food system in the U.S. The general public now has more appreciation for farm workers and meatpacking employees, as well as those in grocery stores and in food transportation who are suddenly recognized as essential frontline workers. It apparently takes a crisis for us to focus clearly on the fragility of this system and the lives of people on whom we depend. In this commentary we discuss the definition of food sovereignty, how it manifests in urban areas, and how the COVID-19 pandemic can trigger viable …

Training For Specialists Vs. Education For Agroecologists, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

I admit to being a slow learner. Graduate school training in agronomy at the University of California, Davis and in plant breeding at Cornell University provided me with top-quality opportunities to acquire the tools for crop improvement, plus the contacts to join professionals at the International Center for Tropical Agriculture in Colombia. As a young scientist dedicated to building on successes of the Green Revolution, I was convinced that genetic changes would solve global hunger. This had been amply demonstrated with the yield increases of wheat in Mexico and India, and with rice in Southeast Asia. Should this success not …

Validation Of Predictive Empirical Weed Emergence Models Of Abutilon Theophrasti Medik Based On Intercontinental Data, Valle Egea-Cobrero, Kevin Bradley, Isabel M. Calha, Adam S. Davis, Jose Dorado, Frank Forcella, John L. Lindquist, Christy L. Sprague, Jose L. Gonzalez-Andujar

Department of Agronomy and Horticulture: Faculty Publications

Good weed management relies on the proper timing of weed control practices in relation to weed emergence dynamics. Therefore, the development of models that predict the timing of emergence may help provide growers with tools to make better weed management decisions. The aim of this study was to validate and compare two previously published predictive empirical thermal time models of the emergence of Abutilon theophrasti growing in maize with data sets from the USA and Europe, and test the hypothesis that a robust and general weed emergence model can be developed for this species. Previously developed Weibull and Logistic models …

Biological And Cellular Functions Of The Microdomain-Associated Fwl/Cnr Protein Family In Plants, Sandra Thibivilliers, Andrew Farmer, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Membrane microdomains/nanodomains are sub-compartments of the plasma membrane enriched in sphingolipids and characterized by their unique protein composition. They play important roles in regulating plant development and plant-microbe interactions including mutualistic symbiotic interactions. Several protein families are associated with the microdomain fraction of biological membranes such as flotillins, prohibitins, and remorins. More recently, GmFWL1, a FWL/CNR protein exclusively expressed in the soybean nodule, was functionally characterized as a new microdomain-associated protein. Interestingly, GmFWL1 is homologous to the tomato FW2-2 protein, a major regulator of tomato fruit development. In this review, we summarize the knowledge gained about the biological, cellular, and …

Allelic Variation In Rice Fertilization Independent Endosperm 1 Contributes To Grain Width Under High Night Temperature Stress, Balpreet K. Dhatt, Puneet Paul, Jaspreet Sandhu, Waseem Hussain, Larissa Irvin, Feiyu Zhu, Maria Arlene Adviento-Borbe, Argelia Lorence, Paul Staswick, Hongfeng Yu, Gota Morota, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

A higher minimum (night-time) temperature is considered a greater limiting factor for reduced rice yield than a similar increase in maximum (daytime) temperature. While the physiological impact of high night temperature (HNT) has been studied, the genetic and molecular basis of HNT stress response remains unexplored.

We examined the phenotypic variation for mature grain size (length and width) in a diverse set of rice accessions under HNT stress. Genome-wide association analysis identified several HNT-specific loci regulating grain size as well as loci that are common for optimal and HNT stress conditions.

A novel locus contributing to grain width under HNT …

Investigation Of Heat-Induced Changes In The Grain Yield And Grains Metabolites, With Molecular Insights On The Candidate Genes In Barley, Mona F.A. Dawood, Yasser S. Moursi, Ahmed Amro, P. Stephen Baenziger, Ahmed Sallam

Department of Agronomy and Horticulture: Faculty Publications

Heat stress is one of the abiotic stresses that cause a significant reduction in barley yield. Climate change will increase the number of heatwaves, which will result in more deterioration in the agricultural sector. Therefore, understanding the physiological changes that occur in the plant to tolerate heat stress is very important. A collection of 60 Egyptian spring barley genotypes has been tested for heat stress under field conditions. To quantify the changes in yield-related traits and the grain-reserve parameters as indicators for heat tolerance, several traits were scored. The causative genes that regulate the variation of all traits of interest …

Weather And Soil In The Us Midwest Influence The Effectiveness Of Single- And Split-Nitrogen Applications In Corn Production, Jason D. Clark, Fabián G. Fernández, James J. Camberato, Paul R. Carter, Richard B. Ferguson, David W. Franzen, Newell R. Kitchen, Carrie A. M. Laboski, Emerson Nafziger, John E. Sawyer, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Splitting the N application into two or more timings may improve corn (Zea mays L.) grain yield and N recovery relative to a single-N application. A 49 site-year study across eight U.S. Midwestern states compared the effect of an at-planting (single-N application) and two split-N applications [45 (45+SD) or 90 kg N ha−1 (90+SD) at planting with the remainder of the total rate (180 or 270 kg N ha−1) applied at V9]. For split-N applications, soil and plant responses were similar between 45+SD and 90+SD 93–98% of the time, indicating the at-planting N rate of 45 kg N ha−1 may …

Organic Fertilizer Abrasive Grits Increase Soil Available Nitrogen, Plant Height, And Biomass, Michael Carlson, Frank Forcella, Samuel E. Wortman, David Clay, Sharon A. Clay

Department of Agronomy and Horticulture: Faculty Publications

In organic cropping systems, air-propelled abrasive grits can be used to control in-row weeds. If the applied abrasive grit is an approved organic fertilizer, these applications may serve a dual purpose of weed control and crop fertility. Laboratory soil incubations examined the N mineralization rates of several grit types with differing C/N ratios (Agra Grit [crushed walnut shells, 170:1], corncob grit [91:1], Sustane [composted turkey litter, 5.0:1], Phytaboost Plant Food [crushed and pelletized soybean meal, 5.0:1]). A greenhouse study determined plant wheat (Triticum aestivum L.), kale (Brassica napus pabluaria DC), and velvetleaf (Abu- tilon theophrasti Medik.) growth response in soils …

Leveraging Genome-Enabled Growth Models To Study Shoot Growth Responses To Water Deficit In Rice, Malachy T. Campbell, Alexandre Grondin, Harkamal Walia, Gota Morota

Department of Agronomy and Horticulture: Faculty Publications

lucidating genotype-by-environment interactions and partitioning its contribution to phenotypic variation remains a challenge for plant scientists. We propose a framework that utilizes genome-wide markers to model genotype-specific shoot growth trajectories as a function of time and soil water availability. A rice diversity panel was phenotyped daily for 21 d using an automated, high-throughput image-based, phenotyping platform that enabled estimation of daily shoot biomass and soil water content. Using these data, we modeled shoot growth as a function of time and soil water content, and were able to determine the time point where an inflection in the growth trajectory occurred. We …

A Systematic Review Of Durum Wheat: Enhancing Production Systems By Exploring Genotype, Environment, And Management (G × E × M) Synergies, Brian L. Beres, Elham Rahmani, John M. Clarke, Patricio Grassini, Curtis J. Pozniak, Cameron Guy Robinson Geddes, Kenton D. Porker, William E. May, Joel Ransom

Department of Agronomy and Horticulture: Faculty Publications

According to the UN-FAO, agricultural production must increase by 50% by 2050 to meet global demand for food. This goal can be accomplished, in part, by the development of improved cultivars coupled with modern best management practices. Overall, wheat production on farms will have to increase significantly to meet future demand, and in the face of a changing climate that poses risk to even current rates of production. Durum wheat [Triticum turgidum L. ssp. durum (Desf.)] is used largely for pasta, couscous and bulgur production. Durum producers face a range of factors spanning abiotic (frost damage, drought, and sprouting) and …

Training Future Agriculture Professionals In Landowner–Tenant Conservation Decision-Making, Andrea Basche, Angie Carter

Department of Agronomy and Horticulture: Faculty Publications

The landowner–tenant relationship is important to the implementation of conser- vation on agricultural lands. Women own or co-own a significant portion of U.S. farmland yet are underrepresented in conservation research. The next generation of agriculture professionals can benefit from first-hand experience in assisting women landowners and their tenants in navigating the complexities of conser- vation decision-making. This article analyzes undergraduate student perceptions of landowner–tenant relationships in conservation management through their engagement in case studies with women landowner–tenant pairs in the Western Corn Belt. Student groups were asked to complete a management improvement plan that both incorporated the agronomic and conservation …

Cover Crops And Weed Suppression In The U.S. Midwest: A Meta-Analysis And Modeling Study, Virginia Nicholas, Rafael Martinez-Feria, David Weisberger, Sarah Carlson, B. Basso, Andrea Basche

Department of Agronomy and Horticulture: Faculty Publications

In addition to soil health and conservation benefits, cover crops (CCs) may offer weed control in the midwestern United States, but individual studies report vary- ing effects. We conducted a meta-analysis of studies measuring weed biomass (WBIO) or density (WDEN) in paired CC and no-cover treatments in corn (Zea mays L.)–soybean [Glycine max (L.) Merr] rotations in the U.S. Midwest. Fifteen studies provided 123 paired comparisons of WBIO and 119 of WDEN. Only grass CCs significantly reduced WBIO, while no CC reduced WDEN. We found no evidence CC management factors (e.g., termination method) directly affected out- comes. Our dataset showed …

Quantifying On‐Farm Nitrous Oxide Emission Reductions In Food Supply Chains, A.J. Eagle, E. Mclellan, E.M. Brawner, M.H. Chantigny, Eric A. Davidson, J.B. Dickey, Bruce A. Linquist, T.M. Maaz, D.E. Pelster, Cameron M. Pittelkow, C. Van Kessel, T.J. Vyn, K. G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

Reducing nitrous oxide (N2O) emissions from agriculture is critical to limiting future global warming. In response, a growing number of food retailers and manufacturers have committed to reducing N2O emissions from their vast networks of farmer suppliers by providing technical assistance and financial incentives. A key challenge for such companies is demonstrating that their efforts are leading to meaningful progress toward their climate mitigation commitments. We show that a simplified version of soil surface nitrogen (N) balance—or partial N balance—the difference between N inputs to and outputs

from a farm field (fertilizer N minus crop N), is a robust indicator …