Horticulture Commons^™

Marker-Assisted Selection To Determine The Introgression Of Rpv-3 Mediated Downy Mildew Resistance In 'Chambourcin' X 'Caberenet Sauvignon' Grapevine Population, Kavya Sri Tummala

Graduate Theses/Dissertations

Downy mildew caused by the fungus, Plasmopara viticola in the grapes is one of the major diseases affecting crop yield throughout the world. Breeding grapes via conventional methods for the downy mildew resistance will take approximately 25-30 years to fully evaluate and release new cultivars. Because of the long breeding cycle in woody plant species like grape, developing DNA markers linked to genes or quantitative trait loci (QTLs) for horticultural traits can greatly accelerate the breeding process and allow a much more accurate selection of progeny. This study aims to determine the presence of resistance in the 267 F1 genotypes …

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 Thomas 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 …

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 …

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 …

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 …

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 …

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 …

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, …

Using Thermal Imaging To Measure Water Stress In Creeping Bentgrass Putting Greens, Joseph G. 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 …

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 celiac 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 …

Evaluation Of Masculinization Treatments To Produce Feminized Hemp Seed (Cannabis Sativa L.), Ted Fitzgerald, J. Wyatt Brown

Master's Theses

Cannabis sativa L. (hemp) develops plants with either male or female flowers, and growers of hemp greatly prefer female flowers which bear the glandular trichomes that contain cannabinoids. Feminized (all female) seeds are highly desired, which are produced by crossing a female plant with a masculinized female plant. Masculinization is achieved through the inhibition of ethylene and/or addition of gibberellins before flower initiation in female plants. The hemp industry uses silver thiosulfate (STS) to masculinize hemp, but spraying silver poses environmental concerns. This study compared STS to three other ethylene-inhibiting agents: aminoethoxyvinylglycine (AVG), cobalt nitrate (CBN), and 1-methylcyclopropene (1-MCP). Treatments …

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 …

Coleoptile Length Comparison Of Three Winter Small Grain Cereals Adapted To The Great Plains, M. Alam, M. Kashif, Amanda Easterly, F. Wang, J. D. Boehm Jr., P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Successful crop stand establishment is critical to realize high yield potential, which is dependent on depth of seed placement to access soil moisture. The coleoptile determines sowing depth by its length and ability to emerge from depth. This study was conducted to assess coleoptile length among three sets of three Great Plains winter small grain cereals—wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and triticale (X triticosecale Wittm.)—and to evaluate the effect of the Rht-B1b dwarfing allele on coleoptile length in wheat and triticale. Fifty seeds of each genotype were sown in wet germination paper in two …

Estimation Of Household Smoke-Exposure Risk Using Demographic And Health Survey (Dhs) Data, Mazbahul G. Ahamad, Fahian Tanin

Department of Agronomy and Horticulture: Faculty Publications

We introduce Stata and R codes to estimate the household smoke-exposure risk (SER) variable using cooking fuel- and cooking place-related information obtained from country-level demographic and health survey (DHS) data. Two categories of cooking fuels (smoke-producing and non-smoke producing fuels) and two categories of cooking places (indoor and outdoor) are used to estimate the household SER. Finally, household SER is classified into four levels of risk: high (cooking indoor using smoke-producing fuels), medium (cooking outdoor using smoke-producing fuels), low (cooking indoor using non-smoke-producing fuels), and very low (cooking outdoor using non-smoke-producing fuels). An example of a household SER calculation using …

The Effect Of Anionic Surfactants On Herbicide Mixtures And Solutions, Ely Daniel Anderson

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

Herbicide mixtures are popular for farmers to delay the evolution of herbicide-resistant biotypes from occurring and control existing herbicide-resistant weeds. Glufosinate is a contact herbicide that has been observed as a mixture partner with many herbicides. In many cases, antagonistic interactions have occurred when using glufosinate in mixture with other herbicides. The antagonistic interactions have resulted in applications with incomplete weed control. Adjuvants have been known to impact an herbicide application by increasing herbicide penetration, spreadability, and efficacy. Adjuvants added to glufosinate mixtures can impact spray applications and increase weed control. The objectives of this research were: (1) investigate the …

Phenotypic Plasticity Of Diverse Sorghum Varieties In Response To Nitrogen Deficit Stress, Mackenzie Zwiener

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

The movement of nutrients from old vegetative tissue to young leaves and reproductive organs is known as senescence. Senescence can be influenced by the environment of a plant, such as, drought, heat, and nutrient stress. These environmental stressors can also influence canopy architecture. Crop canopy consists of several traits including: leaf number, angle, length and width. Past research in crops like maize and rice have shown significant influences of more erect leaves, including, the ability for increased planting density, which optimizes light interception and increases yield. In a field trial of a sorghum association panel including 345 different sorghum varieties …

Does Light Quality Influence Arabidopsis Thaliana Growth In Controlled Environments?, Nathan A. Deppe, Daniel A. Little, Kathleen K. Zapf

Purdue Methods for Arabidopsis Growth

This study examines the use of diverse lamp types, with inherently different spectral attributes, to determine light quality influence on Arabidopsis thaliana growth in controlled environments.

Nozzle Selection And Adjuvant Impact On The Efficacy Of Glyphosate And Ppo-Inhibiting Herbicide Tank-Mixtures, Jesaelen G. Moraes, Thomas R. Butts, Vitor M. Anunciato, Joe D. Luck, Wesley C. Hoffmann, Ulisses R. Antuniassi, Greg R. Kruger

Department of Agronomy and Horticulture: Faculty Publications

PPO-inhibiting herbicides in combination with glyphosate for postemergence applications is a common approach to manage glyphosate- and ALS-inhibitor-resistant weeds. PPO-inhibitors can reduce glyphosate translocation when applied in tank-mixtures, but adjuvants may be used to overcome this effect. Additionally, optimal droplet size may be affected by tank-mixtures of different herbicides and it can be crucial to herbicide efficacy. Field and greenhouse studies were conducted to investigate the impact of nozzle selection and adjuvants on weed control and interactions when applying PPO-inhibitors (fomesafen or lactofen) alone or in tank-mixture with glyphosate to five weed species using six nozzle types. Ultra-coarse droplets were …

Pertumbuhan Tunas Kunyit Tinggi Kurkumin Pada Berbagai Jenis Sitokinin Dan Auksin Secara In Vitro, Erni Suminar, Denny Sobardini Sobarna, Syariful Mubarok, Sulistyaningsih, Ade Setiawan

Jurnal Kultivasi

Kunyit merupakan salah satu tanaman yang banyak dimanfaatkan oleh masyarakat sebagai bahan baku obat tradisional, bumbu dapur, serta zat pewarna alami, sehingga kebutuhannya mengalami peningkatan setiap tahunnya. Penyediaan bibit yang memiliki produktivitas tinggi dalam jumlah banyak dapat dilakukan dengan metode kultur in vitro, namun perlu optimasi media yang sesuai. Penelitian ini bertujuan untuk mencari komposisi zat pengatur tumbuh yang dapat memberikan pertumbuhan planlet yang lebih vigor. Rancangan percobaan yang digunakan yaitu Rancangan Acak Lengkap. Perlakuan terdiri dari penggunaan sitokinin dan auksin pada eksplan kunyit yang diulang tiga kali. Media Murashige and Skoog (MS) digunakan sebagai media dasar dengan perlakuan kombinasi …

Pengaruh Air Kelapa Sebagai Sitokinin Organik Dan Sukrosa Terhadap Pertumbuhan Protocorm Anggrek (Phalaenopsis Hybrid Mp 253 X F1 3363 (M)) In Vitro, Muhammad Isyraq, Lia Amalia, Iis Aisyah

Jurnal Kultivasi

Sitokinin dan sukrosa dibutuhkan untuk meregenerasi protocorm anggrek. Air kelapa diketahui memiliki kandungan sitokinin sehingga berpotensi dijadikan sebagai sitokinin organik. Percobaan ini bertujuan untuk mempelajari pengaruh konsentrasi air kelapa sebagai sitokinin organik dan sukrosa terhadap pertumbuhan protocorm anggrek. Percobaan ini dilaksanakan di Laboratorium Bioteknologi Tanaman, Fakultas Pertanian Universitas Winaya Mukti, Kecamatan Tanjungsari Kabupaten Sumedang. Percobaan dimulai pada bulan Mei sampai dengan bulan Agustus 2019. Rancangan percobaan yang digunakan adalah rancangan acak kelompok dengan dua faktor dan diulang dua kali. Faktor pertama adalah konsentrasi air kelapa, terdiri dari lima taraf yaitu 0 mL L-1, 50 mL L-1, 100 mL L-1, air …

Respons Dua Generasi Tomat Mutan Insensitif Etilen Sletr1-2 Terhadap Cekaman Kekeringan, Bayu Pradana Nur Rahmat, Noladhi Wicaksana, Syariful Mubarok, Muhamad Joddy Ramadhan, Maura Zhafira Putri, Hiroshi Ezura

Jurnal Kultivasi

Buah tomat tergolong ke dalam golongan buah klimaterik. Umur simpan buah tomat sangat dipengaruhi oleh keberadaan etilen. Tomat mutan NIL Sletr1-2 adalah generasi baru dari tomat insensitif etilen. Buah dari tomat mutan NIL Sletr1-2 memiliki umur simpan yang lebih lama dari tomat komersial pada umumnyanamun kehilangan fungsi untuk merespon keberadaan etilen dapat berpengaruh kepada pertumbuhan dan perkembangan tanaman, khususnya dalam kondisi cekaman. Tujuan dari penelitian ini adalah untuk mengetahui efek cekaman kekeringan terhadap dua generasi tomat mutan insensitif etilen (NIL Sletr1-2 dan BC3F1 Sletr1-2), dengan tomat ‘Intan’ sebagai tanaman kontrol. Ketiga tomat tersebut disiram dengan tiga interval waktu yang berbeda, …

Maize Nitrogen Management Using Reactive Sensor And Proactive Maize-N Model Via Fertigation, Mohammed Abdulridha Naser

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

Applying a portion of total nitrogen (N) during the growing season has the potential to improve nitrogen use efficiency (NUE) by achieving greater synchrony between N supply and crop N demand, allowing for responsive adjustments to actual field conditions. Three studies from 2017-2019 evaluated using reactive sensor and proactive Maize-N model for determining in-season N requirements via fertigation in corn. The first study evaluated the integration of reactive sensor and proactive Maize-N model for determining the timing and rate of in-season N via fertigation. Overall, reactive and proactive fertigation treatments reduced total N applied by 35 to 65 kg N …

The Influence Of Adjuvants On Physical Properties, Droplet-Size, And Efficacy Of Glufosinate And Dicamba Plus Glyphosate Solutions, Estefania Gomiero Polli

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

Adjuvants are used in agriculture to improve herbicide activity or application performance. The addition of adjuvants to herbicide solution can enhance its penetration, wettability, and evaporation rates by altering density, viscosity, contact angle between the droplet and plant surface, and droplet surface tension. Furthermore, those alterations in the physical properties of the herbicide solution can result in changes in the droplet-size distribution that directly impact herbicide efficacy. The adoption of glufosinate-based herbicide programs has increased with the widespread occurrence of glyphosate-resistance (GR) weeds in recent years. Also, tank mixture of dicamba and glyphosate has been largely adopted for broad-spectrum weed …

Comparing A Mixed Model Approach To Traditional Stability Estimators For Mapping Genotype By Environment Interactions And Yield Stability In Soybean [Glycine Max (L.) Merr.], Mary M. Happ, George L. Graef, Haichuan Wang, Reka Howard, Luis Posadas, David L. Hyten

Department of Agronomy and Horticulture: Faculty Publications

Identifying genetic loci associated with yield stability has helped plant breeders and geneticists begin to understand the role and influence of genotype by environment (GxE) interactions in soybean [Glycine max (L.) Merr.] productivity, as well as other crops. Quantifying a genotype’s range of performance across testing locations has been developed over decades with dozens of methodologies available. This includes directly modeling GxE interactions as part of an overall model for yield, as well as methods which generate overall yield “stability” values from multi-environment trial data. Correspondence between these methods as it pertains to the outcomes of genome wide association studies …