Digital Commons Network^™

Advancing Agricultural Research Using Machine Learning Algorithms, Spyridon Mourtzinis, Paul D. Esker, James E. Specht, Shawn P. Conley

Department of Agronomy and Horticulture: Faculty Publications

Rising global population and climate change realities dictate that agricultural productivity must be accelerated. Results from current traditional research approaches are difficult to extrapolate to all possible fields because they are dependent on specific soil types, weather conditions, and background management combinations that are not applicable nor translatable to all farms. A method that accurately evaluates the effectiveness of infinite cropping system interactions (involving multiple management practices) to increase maize and soybean yield across the US does not exist. Here, we utilize extensive databases and artificial intelligence algorithms and show that complex interactions, which cannot be evaluated in replicated trials, …

Final Selection Of Quality Protein Popcorn Hybrids, Leandra Parsons, Ying Ren, Abou Yobi, Ruthie Angelovici, Oscar Rodriguez, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Quality Protein Popcorn (QPP) BC₂F₅ inbred lines were produced through an interpopulation breeding system between Quality Protein Maize dent (QPM) and elite popcorn germplasm. In 2019, five QPP F₁ hybrids were selected for further evaluation due to superior agronomics, endosperm protein quality, and popping quality traits. Though these BC₂F₅ QPP hybrids were phenotypically similar to their popcorn parents, the QPP cultivars conveyed slightly inferior popping characteristics when compared to the original popcorn germplasm. The objective of this study was twofold. First, BC₂F₅ inbred lines were crossed to their popcorn parents …

Center For Grassland Studies, September 2021

Center for Grassland Studies: Newsletters

Contents

Nebraska Grazing Conference Recap by Daren Redfearn

Center for Grassland Studies Policy Advisory Committee

Director's Column by Walt Schacht (Interim Director)

Land Use and Property Taxes by Jordan Johnson

Congratulations August 2021 Graduates

Wildfires are Changing the Future of Nebraska’s Woodland-Grassland Complexes by Amanda Hefner

PGA WORKS Scholarship Recipients Announced by PGA Reach

Grazing Livestock Systems Internships Provide Diverse Experience by Bryan Reiling

Jim Choquette Receives Lifetime Achievement Award

Effects Of Micro-Rates Of 2,4-D And Dicamba On Lettuce And Pumpkin In Nebraska, Xinzheng Chen

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

Off-target herbicide injury from dicamba and 2,4-D is an increasingly common problem for specialty crop growers in the Midwestern United States. Both lettuce (Lactuca sativa L.) and pumpkin (Cucurbita spp.) are common specialty crops grown in Nebraska, and their proximity to corn and soybean production makes these crops susceptible to herbicide drift injury and yield loss. The objectives of this thesis research was to quantify crop injury and yield loss in greenhouse- and field-grown lettuce and field-grown pumpkins at different growth stages after exposure to sub-lethal doses of dicamba or 2,4-D. Dose response curves were generated to determine effective dose …

Predicting Non-Native Insect Impact: Focusing On The Trees To See The Forest, Ashley N. Schulz, Angela M. Mech, Matthew P. Ayres, Jamal J.K. Gandhi, Nathan P. Havill, Daniel A. Herms, Angela M. Hoover, Ruth A. Hufbauer, Andrew M. Liebhold, Travis D. Marsico, Kenneth F. Raffa, Patrick C. Tobin, Daniel R. Uden, Kathryn A. Thomas

Department of Agronomy and Horticulture: Faculty Publications

Non-native organisms have invaded novel ecosystems for centuries, yet we have only a limited understanding of why their impacts vary widely from minor to severe. Predicting the impact of non-established or newly detected species could help focus biosecurity measures on species with the highest potential to cause widespread damage. However, predictive models require an understanding of potential drivers of impact and the appropriate level at which these drivers should be evaluated. Here, we used non-native, specialist herbivorous insects of forest ecosystems to test which factors drive impact and if there were differences based on whether they used woody angiosperms or …

Impact Of Cover Crop Monocultures And Mixtures On Organic Carbon Contents Of Soil Aggregates, Daphne Topps, Imam Ul Khabir, Hagir Abdelmagid, Todd Jackson, Javed Iqbal, Boakai K. Robertson, Zahida Hassan Pervaiz, Muhammad Saleem

Department of Agronomy and Horticulture: Faculty Publications

Cover crops are considered an integral component of agroecosystems because of their positive impacts on biotic and abiotic indicators of soil health. At present, we know little about the impact of cover crop types and diversity on the organic carbon (OC) contents of different soil aggregate-size classes. In this study, we investigated the effect of cover plant diversity on OC contents of different soil aggregates, such as macro- (<2000–500 µm), meso- (<500–250 µm), and micro-aggregates (<250 µm). Our experiment included a total of 12 experimental treatments in triplicate; six different monoculture treatments such as chickling vetch (Vicia villosa), crimson clover (Trifolium incarnatum), hairy vetch (Vicia villosa), field peas (Pisum sativum), oilseed radish (Raphanus sativus), and mighty mustard (Brassica juncea), and their three- and six-species mixture treatments, including one unplanted control treatment. We performed this experiment usingdeep pots that contained soil collected from a corn-soybean rotation field. At vegetative maturity of cover plants (about 70 days), we took soil samples, and the soil aggregate-size classes were separated by the dry sieving. We hypothesized that cover crop type and diversity will improve OC contents of different soil aggregate-size classes. We found that cover plant species richness weakly positively increased OC contents of soil macro-aggregates (p = 0.056), whereas other aggregate-size classes did not respond to cover crop diversity gradient. Similarly, the OC contents of macroaggregates varied significantly (p = 0.013) under cover crop treatments, though neither monoculture nor mixture treatments showed significantly higher OC contents than the control treatment in this short-term experiment. Interestingly, the inclusion of hairy vetch and oilseed radish increased and decreased the OC contents of macro- and micro-aggregates, respectively. Moreover, we found a positive correlation between shoot biomass and OC contents of macroaggregates. Overall, our results suggest that species-rich rather than -poor communities may improve OC contents of soil macroaggregates, which constitute a major portion of soil systems, and are also considered as important indicators of soil functions.

Enhancing Our Understanding Of Plant Cell-To-Cell Interactions Using Single-Cell Omics, Sandra Thibivilliers, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Plants are composed of cells that physically interact and constantly adapt to their environment. To reveal the contribution of each plant cells to the biology of the entire organism, their molecular, morphological, and physiological attributes must be quantified and analyzed in the context of the morphology of the plant organs. The emergence of single-cell/nucleus omics technologies now allows plant biologists to access different modalities of individual cells including their epigenome and transcriptome to reveal the unique molecular properties of each cell composing the plant and their dynamic regulation during cell differentiation and in response to their environment. In this manuscript, …

Tandem Duplicate Expression Patterns Are Conserved Between Maize Haplotypes Of The Α-Zein Gene Family, Preston Hurst, James C. Schnable, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Tandem duplication gives rise to copy number variation and subsequent functional novelty among genes as well as diversity between individuals in a species. Functional novelty can result from either divergence in coding sequence or divergence in patterns of gene transcriptional regulation. Here, we investigate conservation and divergence of both gene sequence and gene regulation between the copies of the α-zein gene family in maize inbreds B73 and W22. We used RNA-seq data generated from developing, self-pollinated kernels at three developmental stages timed to coincide with early and peak zein expression. The reference genome annotations for B73 and W22 were modified …

Evaluating Evapotranspiration And Management Of Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri S. Watson), Jasmine Mausbach

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

Palmer amaranth (PA) is the most problematic weed in agronomic cropping systems in the United States. Acetolactate synthase (ALS) inhibitor-/glyphosate-resistant (GR) PA has been confirmed in Nebraska and is widespread in several counties. Soybean resistant to isoxaflutole/glufosinate/glyphosate has been developed to provide additional herbicide sites of action for control of herbicide-resistant weeds. The objectives of this study were to evaluate herbicide programs for control of ALS inhibitor/GR PA and their effect on PA density and biomass, as well as soybean injury and yield in isoxaflutole/glufosinate/glyphosate-resistant soybean. A PRE herbicide fb glufosinate controlled PA 80%–99% 21 d after late-POST in 2018 …

Quantifying The Combined Effect Of Abiotic Factors On The Decomposition Of Organic Matter In Semiarid Grassland Soils, Elnazsadat Hosseiniaghdam

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

Grassland ecosystems play a critical role in the global carbon cycle, and their cumulative carbon dioxide (CO2) emissions can be affected by animal grazing where litter (i.e., dead plant material) is trampled into the soil. However, the subsequent effects of trampling on litter decomposition are not well understood. Meanwhile, abiotic factors, especially temperature and soil moisture, are known to strongly affect litter decomposition. Due to the very small number of published studies that have considered litter placement, either litter on top of soil or litter mixed with soil as a factor in litter decomposition under different temperature and soil moisture …

Effects Of Cultivars And Nitrogen Management On Wheat Grain Yield And Protein, Deepak Ghimire, Saurav Das, Nathan D. Mueller, Cody F. Creech, Dipak Santra, P Stephen Baenziger, Amanda C. Easterly, Brian Maust, Bijesh Maharjan

Department of Agronomy and Horticulture: Faculty Publications

Low grain protein in hard red winter (HRW) wheat (Triticum aestivum L.) is a serious challenge for rainfed wheat growers, particularly in years with elevated grain yield. Proper nitrogen (N) management with adequate N rate and application timing is critical for optimizing grain yield and protein content. This 2-yr experiment evaluated the effects of different N rates and application timings (fall, spring, and split) on grain yield and protein of two HRW wheat cultivars. Field studies were conducted at four different sites across Nebraska under rainfed conditions in 2018/2019 (Year 1) and 2019/2020 (Year 2). A split plot randomized complete …

Management Of Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri S. Watson) In Dicamba/Glyphosate-Resistant Soybean, Shawn Mcdonald

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

While not a historically problematic weed in Nebraska, Palmer amaranth has become increasingly problematic in many agronomic cropping systems. Throughout the state, several cohorts of Palmer amaranth have been found resistant to several different sites of action. Of major concern is a population found resistant to glyphosate the most common post-emergence herbicide in Nebraska. As chemical control methods are the most common forms of weed control throughout the state methods alternatives or enhancements are highly desired. Two field experiments were conducted in 2018 and 2019 at a grower’s field near Carleton, Nebraska with the objectives to evaluate the effects of …

An Assessment Of The Factors Influencing The Prediction Accuracy Of Genomic Prediction Models Across Multiple Environments, Sarah Widener, George Graef, Alexander E. Lipka, Diego Jarquin

Department of Agronomy and Horticulture: Faculty Publications

The effects of climate change create formidable challenges for breeders striving to produce sufficient food quantities in rapidly changing environments. It is therefore critical to investigate the ability of multi-environment genomic prediction (GP) models to predict genomic estimated breeding values (GEBVs) in extreme environments. Exploration of the impact of training set composition on the accuracy of such GEBVs is also essential. Accordingly, we examined the influence of the number of training environments and the use of environmental covariates (ECs) in GS models on four subsets of n = 500 lines of the soybean nested association mapping (SoyNAM) panel grown in …

Generalist Bird Exhibits Site-Dependent Resource Selection, Samantha M. Cady, Craig A. Davis, Samuel D. Fuhlendorf, Rheinhardt Scholtz, Daniel R. Uden, Dirac Twidwell

Department of Agronomy and Horticulture: Faculty Publications

Quantifying resource selection (an organism's disproportionate use of available resources) is essential to infer habitat requirements of a species, develop management recommendations, predict species responses to changing conditions, and improve our understanding of the processes that underlie ecological patterns. Because study sites, even within the same region, can differ in both the amount and the arrangement of cover types, our objective was to determine whether proximal sites can yield markedly different resource selection results for a generalist bird, northern bobwhite (Colinus virginianus). We used 5 years of telemetry locations and newly developed land cover data at two, geographically distinct but …

Data From A Public–Industry Partnership For Enhancing Corn Nitrogen Research, C J. Ransom, J D. Clark, G M. Bean, C J. Bandura, M Shafer, N R. Kitchen, J J. Camberato, P R. Carter, R B. Ferguson, F G. Fernandez, D W. Franzen, C.A.M. Laboski, D B. Myers, E D. Nafziger, J E. Sawyer, J F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Improving corn (Zea mays L.) N management is pertinent to economic and environmental objectives. However, there are limited comprehensive data sources to develop and test N fertilizer decision aid tools across a wide geographic range of soil and weather scenarios. Therefore, a public-industry partnership was formed to conduct standardized corn N rate response field studies throughout the U.S. Midwest. This research was conducted using a standardized protocol at 49 site-years across eight states over the 2014 to 2016 growing seasons with many soil, plant, and weather related measurements. This note provides the data (found in supplemental files), outlines the data, …

Structural Insights Into The Functional Divergence Of Whib-Like Proteins In Mycobacterium Tuberculosis, Tao Wan, Magdalena Horova, Daisy Guiza Beltran, Shanren Li, Huey-Xian Wong, Li-Mei Zhang

Department of Agronomy and Horticulture: Faculty Publications

WhiB7 represents a distinct subclass of transcription factors in the WhiB-Like (Wbl) family, a unique group of iron-sulfur (4Fe-4S] cluster-containing proteins exclusive to the phylum of Actinobacteria. In Mycobacterium tuberculosis (Mtb), WhiB7 interacts with domain 4 of the primary sigma factor (σ_^A4) in the RNA polymerase holoenzyme and activates genes involved in multiple drug resistance and redox homeostasis. Here, we report crystal structures of the WhiB7:σ^A₄ complex alone and bound to its target promoter DNA at 1.55-Å and 2.6-Å resolution, respectively. These structures show how WhiB7 regulates gene expression by interacting with both …

Center For Grassland Studies, July 2021

Center for Grassland Studies: Newsletters

Contents

21st Nebraska Grazing Conference on the Horizon by Daren Redfearn

Center for Grassland Studies Policy Advisory Committee

Director's Column by Walt Schacht (Interim Director)

21st Annual Nebraska Grazing Conference Schedule, August 9-11, 2021

Club Officers Elected for FY 21-22 by Jessica Windh

2021 Fall Seminar Series Schedule

CGS Scholarships and Fellowship Awarded for FY 21-22

Congratulations May 2021 Graduates

Comparative Transcriptome Analysis Reveals Genetic Mechanisms Of Sugarcane Aphid Resistance In Grain Sorghum, Desalegn D. Serba, Xiaoxi Meng, James Schnable, Elfadil Bashir, J P. Michaud, P V. Vara Prasad, Ramasamy Perumal

Department of Agronomy and Horticulture: Faculty Publications

The sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae) (SCA), has become a major pest of grain sorghum since its appearance in the USA. Several grain sorghum parental lines are moderately resistant to the SCA. However, the molecular and genetic mechanisms underlying this resistance are poorly understood, which has constrained breeding for improved resistance. RNA-Seq was used to conduct transcriptomics analysis on a moderately resistant genotype (TAM428) and a susceptible genotype (Tx2737) to elucidate the molecular mechanisms underlying resistance. Differential expression analysis revealed differences in transcriptomic profile between the two genotypes at multiple time points after infestation by SCA. Six gene …

Fostering A Climate-Smart Intensification For Oil Palm, Juan Pablo Monzon, Maja A. Slingerland, Suroso Rahutomo, Fahmuddin Agus, Thomas Oberthür, José F. Andrade, Antoine Couëdel, Juan I. Rattalino Edreira, Willem Hekman, Rob Van Den Beuken, Fandi Hidayat, Iput Pradiko, Dwi K.G. Purwantomo, Christopher R. Donough, Hendra Sugianto, Ya Li Lim, Thomas Farrell, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Oil palm production in Indonesia illustrates the intense pressure that exists worldwide to convert natural ecosystems to agricultural production. Oil palm production has increased because of expansion of cultivated area rather than due to average-yield increases. We used a data-rich modelling approach to investigate how intensification on existing plantations could help Indonesia meet palm oil demand while preserving fragile ecosystems. We found that average current yield represents 62% and 53% of the attainable yield in large and smallholder plantations, respectively. Narrowing yield gaps via improved agronomic management, together with a limited expansion that excludes fragile ecosystems, would save 2.6 million …

Morphophysiological And Molecular Characterization Of Millet (Panicum Miliaceum L.) Varieties For Crop Improvement In Western Europe, Massimo Vischi, Nicola `Zorzin, Maria Bernhart, Johanna Winkler, Dipak Santra, Carla Pappalardo, Stefano Marchetti

Department of Agronomy and Horticulture: Faculty Publications

Background: Global warming and issues in favour of a more sustainable agriculture suggest a reconsideration of minor cereals in European agrosystems. Compared to other summer crops, proso millet has a remarkable drought resistance and could be used to improve crop rotation and biodiversity. Proso millet is also increasingly sought by industry to produce novel foods such as those designed for coeliac patients. In this study, a thorough characterization of 11, commercially available, proso millet (Panicum milliaceum L.) varieties was carried out as a preliminary step for crop reintroduction and breeding in Western Europe. Methods: The cultivars under evaluation were introduced …

Physical–Chemical Properties, Droplet Size, And Efficacy Of Dicamba Plus Glyphosate Tank Mixture Influenced By Adjuvants, Estefania Gomiero Polli, Guilherme Sousa Alves, Joao Victor De Oliveira, Greg Robert Kruger

Department of Agronomy and Horticulture: Faculty Publications

Dicamba plus glyphosate tank mixture have been largely adopted for postemergence weed control after the development of dicamba-tolerant crops. Ammonium sulfate is commonly used as water conditioner (WC) to increase glyphosate efficacy, but its use is restricted for dicamba herbicides. The use of non-AMS water conditioner and other adjuvants could be a way to optimize efficacy of this tank mixture while mitigating herbicide off-target movement. The objective of this study was to determine the physical–chemical properties and droplet size distribution of dicamba and glyphosate solutions with and without non-AMS WC alone and tank mixed with other adjuvants and evaluate the …

Biocomposites Of Low-Density Polyethylene Plus Wood Flour Or Flax Straw: Biodegradation Kinetics Across Three Environments, Anna K. Zykova, Petr V. Pantyukhov, Elena E. Mastalygina, Christian Chaverri-Ramos, Svetlana G. Nikolaeva, Jose J. Saavedra-Arias, Anatoly A. Popov, Sam E. Wortman, Matheus Poletto

Department of Agronomy and Horticulture: Faculty Publications

The purpose of this study was to assess the potential for biocomposite films to biodegrade in diverse climatic environments. Biocomposite films based on polyethylene and 30 wt.% of two lignocellulosic fillers (wood flour or flax straw) of different size fractions were prepared and studied. The developed composite films were characterized by satisfactory mechanical properties that allows the use of these materials for various applications. The biodegradability was evaluated in soil across three environments: laboratory conditions, an open field in Russia, and an open field in Costa Rica. All the samples lost weight and tensile strength during biodegradation tests, which was …

Toward Sustainable Production Of Value-Added Bioenergy And Industrial Oils In Oilseed And Biomass Feedstocks, Kiyoul Park, Sanju A. Sanjaya, Truyen Quach, Edgar B. Cahoon

Center for Plant Science Innovation: Faculty and Staff Publications

Plant fatty acids are used forfood, feed, fuel, and industrial materials. Structurally and chemically diverse fatty acids, referred to as unusual or specialized fatty acids, are found in the seed oils of diverse plant species. Many unusual fatty acids have potential use as alternative and renewable sources of biofuels and biobased industrial feedstocks due to their variant structures' physical or functional properties. Oils enriched in these fatty acids can increase the value of oilseed crops and provide co-products that can be readily extracted from lignocellulosic materials in biomass crops. Here, we describe recent progress in strategies for enhancement of oil …

Critical Time For Weed Removal In Corn As Influenced By Planting Pattern And Pre Herbicides, Dejan Nedeljkovic, Stevan Knezevic, Dragana Bozic, Sava Vrbnicanin

Department of Agronomy and Horticulture: Faculty Publications

Determining the critical time for weed removal (CTWR) is essential for the development of an integrated weed management plan. Therefore, field experiments were conducted to evaluate the effects of two planting patterns (standard and twin-row) with and without PRE-applied herbicides on CTWR in corn. Experiments were laid out in a split-plot arrangement with two main plots: (i) standard row planting (SRP) that is 70 cm wide, and (ii) twin-row planting (TRP) with 50 cm distance between each set of double rows. Each main plot was divided into two sub-plots (with and without PRE herbicides). The sub-sub-plots consisted of seven weed …

Disruption Of Long-Chain Base Hydroxylation Alters Growth And Impacts Sphingolipid Synthesis In Physcomitrella Patens, Abraham R. Steinberger, William Oscar Merino, Rebecca E. Cahoon, Edgar B. Cahoon, Daniel V. Lynch

Center for Plant Science Innovation: Faculty and Staff Publications

Sphingolipids have roles as membrane structural components and as bioactive molecules in plants. In Physcomitrella patens, 4-hydroxysphinganine (phytosphingosine, t18:0) is the predominant sphingolipid long-chain base (LCB). To assess the functional significance of t18:0, CRISPR-Cas9 mutagenesis was used to generate mutant lines lacking the sole SPHINGOID BASE HYDROXYLASE (SBH) gene encoding the hydroxylase responsible for converting sphinganine (d18:0) to t18:0. Total sphingolipid content in sbh protonemata was 2.4-fold higher than in wild-type. Modest changes in glycosyl inositolphosphorylceramide (GIPC) glycosylation patterns occurred. Sphingolipidomic analyses of mutants lacking t18:0 indicated modest alterations in acyl-chain pairing with d18:0 in GIPCs and ceramides, but dramatic …

Sweet Sorghum Genotypes Tolerant And Sensitive To Nitrogen Stress Select Distinct Root Endosphere And Rhizosphere Bacterial Communities, Lucas Dantas Lopes, Yen Ning Chai, Ellen L. Marsh, John F. Rajewski, Ismail Dweikat, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

The belowground microbiomes have many beneficial functions that assist plant growth, including nutrient cycling, acquisition and transport, as well as alleviation of stresses caused by nutrient limitations such as nitrogen (N). Here we analyzed the root endosphere, rhizosphere and soil bacterial communities of seven sweet sorghum genotypes differing in sensitivity to N-stress. Sorghum genotypes were grown in fields with no (low-N) or sufficient (high-N) N. The dry shoot weight ratio (low-N/high-N) was used to determine N-stress sensitivity. Our hypothesis was that genotypes tolerant and sensitive to N-stress select distinct bacterial communities. The endosphere and rhizosphere bacterial community structure were significantly …

Meta-Analysis Identifies Pleiotropic Loci Controlling Phenotypic Trade-Offs In Sorghum, Ravi V. Mural, Marcin Grzybowski, Miao Chenyong, Alyssa Damke, Sirjan Sapkota, Richard E. Boyles, Maria G. Salas Fernandez, Patrick S. Schnable, Brandi Sigmon, Stephen Kresovich, James C. Schnable

Department of Plant Pathology: Faculty Publications

Community association populations are composed of phenotypically and genetically diverse accessions. Once these populations are genotyped, the resulting marker data can be reused by different groups investigating the genetic basis of different traits. Because the same genotypes are observed and scored for a wide range of traits in different environments, these populations represent a unique resource to investigate pleiotropy. Here, we assembled a set of 234 separate trait datasets for the Sorghum Association Panel, a group of 406 sorghum genotypes widely employed by the sorghum genetics community. Comparison of genome-wide association studies (GWAS) conducted with two independently generated marker sets …

Using Thermal Imaging To Measure Water Stress In Creeping Bentgrass Putting Greens, Joe Foral Jr.

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

Thermal imaging is a developing tool that can help turf managers reduce water consumption and improve irrigation scheduling, but in-depth studies are needed to maximize this potential. This study evaluated the ability of thermal imaging to identify water stress in a creeping bentgrass (Agrostis stolonifera ‘007’) putting green. Water use and canopy temperature (T_c) were measured for plots subjected to three levels of measured water replacement (full, half, and none) to evaluate changes over a range of soil water potentials (SWP). Water use was consistent across the irrigation treatments up to several days before observed wilt …

Rhizosphere Microbiomes In A Historical Maize-Soybean Rotation System Respond To Host Species And Nitrogen Fertilization At The Genus And Subgenus Levels, Michael A. Meier, Martha G. Lopez-Guerrero, Ming Guo, Marty Schmer, Josh Herr, James Schnable, James R. Alfano, Jinliang Yang

Department of Agronomy and Horticulture: Faculty Publications

Root-associated microbes are key players in plant health, disease resistance, and nitrogen (N) use efficiency. It remains largely unclear how the interplay of biological and environmental factors affects rhizobiome dynamics in agricultural systems. In this study, we quantified the composition of rhizosphere and bulk soil microbial communities associated with maize (Zea mays L.) and soybean (Glycine max L.) in a long-term crop rotation study under conventional fertilization and low-N regimes. Over two growing seasons, we evaluated the effects of environmental conditions and several treatment factors on the abundance of rhizosphere- and soil-colonizing microbial taxa. Time of sampling, host plant species, …

Improved Taste And Texture In Novel Popcorn Varieties Compared To Conventional Lines, Leandra Parsons, Oscar Rodriguez, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Abstract Quality Protein Popcorn (QPP) varieties were bred out of a unique germplasm pool derived from Quality Protein dent Maize and conventional popcorn lines. To identify and compare distinctive characteristics within this population, a new sensory method was employed that coupled hedonic numeric rankings of common sensory traits appearance, aroma, texture, and taste with an “overall likability” score while requiring the selection of specific descriptors for taste and texture. Participants tasted six popcorn cultivars, rated each sample based on sensory factors, and offered specific descriptors for taste and texture. This sensory method identified two QPP hybrids with higher overall likability …