Horticulture Commons^™

Rice Chalky Grain 5 Regulates Natural Variation For Grain Quality Under Heat Stress, Anil Kumar Nalini Chandran, Jaspreet Sandhu, Larissa Irvin, Puneet Paul, Balpreet K. Dhatt, Waseem Hussain, Tian Gao, Paul E. Staswick, Hongfeng Yu, Gota Morota, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Heat stress occurring during rice (Oryza sativa) grain development reduces grain quality, which often manifests as increased grain chalkiness. Although the impact of heat stress on grain yield is well-studied, the genetic basis of rice grain quality under heat stress is less explored as quantifying grain quality is less tractable than grain yield. To address this, we used an image-based colorimetric assay (Red, R; and Green, G) for genome-wide association analysis to identify genetic loci underlying the phenotypic variation in rice grains exposed to heat stress. We found the R to G pixel ratio (RG) derived from mature …

Alfalfa Water Productivity And Yield Gaps In The U.S. Central Great Plains, Kaylin P. Fink, Patricio Grassini, Alexandre Rocateli, Leonardo M. Bastos, Jude Kastens, Luke P. Ryan, Xiaomao Lin, Andres Patrignani, Romulo P. Lollato

Department of Agronomy and Horticulture: Faculty Publications

Context: Yield gap (Yg) analyses using farmer-reported yield and management data have been performed for a number of annual grain crops, but it lacks for perennial forages. The U.S. accounts for 21 % of the global alfalfa production with a large rainfed area located in the central Great Plains, serving as an interesting case-study for Yg in perennial forages. Most existing alfalfa Yg analyses quantified the magnitude of the Yg but failed to identify associated management practices to reduce it. Challenging this analysis, a systematic benchmark for alfalfa water productivity [WP, kg dry matter per mm evapotranspiration (ETc)] that …

Effect Of Water Stress On Weed Germination, Growth Characteristics, And Seed Production: A Global Meta-Analysis, Mandeep Singh, Resham Thapa, Meetpal Singh Kukal, Suat Irmak, Steven Mirsky, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Weeds compete with crops for soil moisture, along with other resources, which can impact the germination, growth, and seed production of weeds; however, this impact has not been systematically recorded and synthesized across diverse studies. To address this knowledge gap, a global meta-analysis was conducted using 1,196 paired observations from 86 published articles assessing the effect of water stress on weed germination, growth characteristics, and seed production. These studies were conducted and published during 1970 through 2020 across four continents (Asia, Australia, Europe, and North America). Imposed water stress was expressed as solution osmotic potential (ψsolution), soil water potential (ψsoil), …

Agronomic And Quality Impact Of A Shortened Translocation For Wheat Streak Mosaic Virus Resistance, Mary J. Guttieri, Robert L. Bowden, Guorong Zhang, Scott Haley, Katherine Anna Frels, Gary L. Hein, Katherine W. Jordan

Department of Agronomy and Horticulture: Faculty Publications

Wheat streak mosaic virus (WSMV) is a mite-vectored virus with substantial economic impact on wheat production. One of the effective sources of resistance to WSMV, Wsm1, is carried on a translocation from Thinopyrum intermedium. The original whole arm form of this translocation (T4DL·4JsS) was highly effective against WSMV but carried a substantial yield penalty in the absence of the virus. Shorter recombinants of the Th. intermedium translocation are now available. This study characterized the agronomic performance of near-isogenic sib-pair families in 10 yield trials using one of these shortened T4DL·4DS-4J^sS translocations, named “rec213,” in the absence …

The Genomic And Bulked Segregant Analysis Of Curcuma Alismatifolia Revealed Its Diverse Bract Pigmentation, Xuezhu Liao, Yuanjun Ye, Xiaoni Zhang, Dan Peng, Mengmeng Hou, Gaofei Fu, Jianjun Tan, Jianli Zhao, Rihong Jiang, Yechun Xu, Jinmei Liu, Jinliang Yang, Wusheng Liu, Luke R. Tembrock, Genfa Zhu, Zhiqiang Wu

Department of Agronomy and Horticulture: Faculty Publications

Compared with most flowers where the showy part comprises specialized leaves (petals) directly subtending the reproductive structures, most Zingiberaceae species produce showy ‘‘flowers’’ through modifications of leaves (bracts) subtending the true flowers throughout an inflorescence. Curcuma alismatifolia, belonging to the Zingiberaceae family, a plant species originating from Southeast Asia, has become increasingly popular in the flower market worldwide because of its varied and esthetically pleasing bracts produced in different cultivars. Here, we present the chromosome-scale genome assembly of C. alismatifolia ‘‘Chiang Mai Pink’’ and explore the underlying mechanisms of bract pigmentation. Comparative genomic analysis revealed C. alismatifolia contains a …

Nebline, October 2022

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

4-H Youth Thrive at Super Fair With Community Support

Apples by Nebraska Extension Staff and Interns

Recipes of the Month: Crunchy Apple Roll and Easy Apple Salad by Kayla Colgrove

Fall Watering Aids Tree & Shrub Health by Sarah Browning

Garden Guide: Things to Do This Month

Maintaining Your Septic System by Becky Schuerman

A Wasp in Disguise: The Velvet Ant by Kait Chapman

4-H’ers Test Family and Consumer Science Skills at Life Challenge

4-H’ers Test Their Knowledge of Animals and Decision-Making Skills at PASE

4-H Announcements for 4-H'ers and Volunteers

Heart of 4-H Volunteer Award: Capital City Horse and …

Cyclic Adp Ribose Isomers: Production, Chemical Structures, And Immune Signaling, Mohammad K. Manik, Yun Shi, Sulin Li, Mark A. Zaydman, Neha Damaraju, Samuel Eastman, Thomas G. Smith, Weixi Gu, Veronika Masic, Tamim Mosaiab, James S. Weagley, Steven J. Hancock, Eduardo Vasquez, Lauren Hartley-Tassell, Nestoras Kargios, Natsumi Maruta, Bryan Y.J. Lim, Hayden Burdett, Michael J. Landsberg, Mark A. Schembri, Ivan Prokes, Lijiang Song, Murray Grant, Aaron Diantonio, Jeffrey D. Nanson, Ming Guo, Jeffrey Milbrandt, Thomas Ve, Bostjan Kobe

Department of Agronomy and Horticulture: Faculty Publications

Cyclic adenosine diphosphate (ADP)–ribose (cADPR) isomers are signaling molecules produced by bacterial and plant Toll/interleukin-1 receptor (TIR) domains via nicotinamide adenine dinucleotide (oxidized form) (NAD+) hydrolysis. We show that v-cADPR (2′cADPR) and v2-cADPR (3′cADPR) isomers are cyclized by O-glycosidic bond formation between the ribose moieties in ADPR. Structures of 2′cADPR-producing TIR domains reveal conformational changes that lead to an active assembly that resembles those of Toll-like receptor adaptor TIR domains. Mutagenesis reveals a conserved tryptophan that is essential for cyclization. We show that 3′cADPR is an activator of ThsA effector proteins from the bacterial antiphage defense system termed Thoeris and …

Spatial Patterns Of Woody Plant Encroachment In A Temperate Grassland, Dillon T. Fogarty, Robert B. Peterson, Dirac Twidwell

Department of Agronomy and Horticulture: Faculty Publications

Context Woody encroachment is the process whereby grasslands transition to a woody-dominated state. This process is a global driver of grassland decline and is ultimately the outcome of increased woody plant recruitment in grasslands. Yet, little is known about how recruitment distances structure spatial patterns of encroachment.

Objectives Here, we develop a recruitment curve to describe the scatter of woody plant recruitment around seed sources and examine how this structures spatial patterns of encroachment.

Methods We developed a recruitment curve for Juniperus virginiana using an encroachment dataset that captures spread from tree plantings into treeless grassland sites in the Nebraska …

The Heterogeneity In The Landscape Of Gene Dominance In Maize Is Accompanied By Unique Chromatin Environments, Liangwei Yin, Gen Xu, Jinliang Yang, Meixia Zhao

Department of Agronomy and Horticulture: Faculty Publications

Subgenome dominance after whole-genome duplication (WGD) has been observed in many plant species. However, the degree to which the chromatin environment affects this bias has not been explored. Here, we compared the dominant subgenome (maize1) and the recessive subgenome (maize2) with respect to patterns of sequence substitutions, genes expression, transposable element accumulation, small interfering RNAs, DNA methylation, histone modifications, and accessible chromatin regions (ACRs). Our data show that the degree of bias between subgenomes for all the measured variables does not vary significantly when both of the WGD genes are located in pericentromeric regions. Our data further indicate that the …

Next-Generation Technologies Unlock New Possibilities To Track Rangeland Productivity And Quantify Multi-Scale Conservation Outcomes, Caleb P. Roberts, David E. Naugle, Brady W. Allred, Victoria M. Donovan, Dillon T. Fogarty, Matthew O. Jones, Jeremy D. Maestas, Andrew C. Olsen, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

Historically, relying on plot-level inventories impeded our ability to quantify large-scale change in plant biomass, a key indicator of conservation practice outcomes in rangeland systems. Recent technological advances enable assessment at scales appropriate to inform management by providing spatially comprehensive estimates of productivity that are partitioned by plant functional group across all contiguous US rangelands. We partnered with the Sage Grouse and Lesser Prairie-Chicken Initiatives and the Nebraska Natural Legacy Project to demonstrate the ability of these new datasets to quantify multi-scale changes and heterogeneity in plant biomass following mechanical tree removal, prescribed fire, and prescribed grazing. In Oregon’s sagebrush …

Cytogenetic And Genomic Characterization Of A Novel Tall Wheatgrass‑Derived Fhb7 Allele Integrated Into Wheat B Genome, Wei Zhang, Tatiana Danilova, Mingyi Zhang, Shuangfeng Ren, Xianwen Zhu, Qijun Zhang, Shaobin Zhong, Linda Dykes, Jason Fiedler, Steven Xu, Katherine Frels, Stephen Wegulo, Jeffrey Boehm Jr., Xiwen Cai

Department of Agronomy and Horticulture: Faculty Publications

A novel tall wheatgrass-derived (Thinopyrum elongatum, genome EE) Fhb7 allele, designated Fhb7^The2, was identified and integrated into the wheat B genome through a small 7B–7E translocation (7BS·7BL–7EL) involving the terminal regions of the long arms. Fhb7^The2 conditions significant Type II resistance to Fusarium head blight (FHB) in wheat. Integration of Fhb7^The2 into the wheat B genome makes this wild species-derived FHB resistance gene usable for breeding in both common and durum wheat. By contrast, other Fhb7 introgression lines involving wheat chromosome 7D can be utilized only in common wheat breeding programs, not in durum …

How Digital Is Agriculture In A Subset Of Countries From South America? Adoption And Limitations, Laila A. Puntel, É. L. Bolfe, R. J. M. Melchiori, R. Ortega, G. Tiscornia, A. Roel, F. Scaramuzza, S. Best, A. G. Berger, D. S. S. Hansel, D. Palacios Durán, G. R. Balboa

Department of Agronomy and Horticulture: Faculty Publications

Digital agriculture (DA) can contribute solutions to meet an increase in healthy, nutritious, and affordable food demands in an efficient and sustainable way. South America (SA) is one of the main grain and protein producers in the world but the status of DA in the region is unknown. A systematic review and case studies from Brazil, Argentina, Uruguay, and Chile were conducted to address the following objectives: (1) quantify adoption of existing DA technologies, (2) identify limitations for DA adoption; and (3) summarise existing metrics to benchmark DA benefits. Level of DA adoption was led by Brazil and Argentina followed …

Cropland Reference Ecological Unit: A Land Classification Unit For Comparative Soil Studies, Saurav Das, Bijesh Maharjan

Department of Agronomy and Horticulture: Faculty Publications

There is a growing consensus on a need for measuring the dynamic soil properties of croplands and even comparisons with a reference state or native land. These measurements and paired comparisons will create the capacity to determine soil health management effects and targets. However, the complex soil heterogeneity and climate variations make soil health potential variable and confound the effects of land-use and management practices and comparisons between soils from different sites. Identifying a discrete landmass unit where all soils have similar health potential will be critical in conducting meaningful comparative studies and measuring the impact of conservation practices. This …

Cell-Type-Specific Profiling Of The Arabidopsis Thaliana Membrane Protein-Encoding Genes, Sergio Alan Cervantes-Pérez, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Membrane proteins work in large complexes to perceive and transduce external signals and to trigger a cellular response leading to the adaptation of the cells to their environment. Biochemical assays have been extensively used to reveal the interaction between membrane proteins. However, such analyses do not reveal the unique and complex composition of the membrane proteins of the different plant cell types. Here, we conducted a comprehensive analysis of the expression of Arabidopsis membrane proteins in the different cell types composing the root. Specifically, we analyzed the expression of genes encoding membrane proteins interacting in large complexes. We found that …

Cell-Type-Specific Profiling Of The Arabidopsis Thaliana Membrane Protein-Encoding Genes, Sergio Alan Cervantes-Pérez, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Membrane proteins work in large complexes to perceive and transduce external signals and to trigger a cellular response leading to the adaptation of the cells to their environment. Biochemical assays have been extensively used to reveal the interaction between membrane proteins. However, such analyses do not reveal the unique and complex composition of the membrane proteins of the different plant cell types. Here, we conducted a comprehensive analysis of the expression of Arabidopsis membrane proteins in the different cell types composing the root. Specifically, we analyzed the expression of genes encoding membrane proteins interacting in large complexes. We found that …

Australian Cleotychini Planthoppers: Review Of The Genus Cleotyche Emeljanov, 1997 With Three New Species (Hemiptera: Fulgoromorpha: Dictyopharidae), Jérôme Constant, Linda Semeraro, Melinda L. Moir

Biosecurity Research Articles

The genus Cleotyche in the monotypic Australian planthopper tribe Cleotychini (Fulgoroidea: Dictyopharidae) is reviewed. The subgenus Griseotyche subgen. nov. is described to accommodate one species Cleotyche blanda Emeljanov, 2011 while the second species, C. mariae Emeljanov, 1997, is retained in the subgenus Cleotyche (Cleotyche) Emeljanov, 1997. Three new species of Cleotyche (Cleotyche) from Queensland, C. (Cleotyche) christinae sp. nov. from Cania Gorge National Park, C. (Cleotyche) francescoi sp. nov. from Eurimbula National Park and C. (Cleotyche) montana sp. nov. from Blackdown Tableland National Park are described and compared to the …

Determination Of Fungicide Resistance In Botrytis Cinerea On Wine Grapes In California's Central Coast Region, Evelyn Alvarez-Mendoza

Master's Theses

Botrytis bunch rot, caused by Botrytis cinerea, is a fungal disease that primarily affects the fruit of wine grapes. Infection of fruit consequently results in reduced yields and wine quality. These factors lead to significant economic losses for growers which prompts the implementation of management practices to control the disease. One objective of this study was to evaluate the level of resistance that populations of B. cinerea in the Central Coast region showed to various chemicals. A fungicide assay was conducted to determine resistant phenotypes to six fungicide active ingredients (pyrimethanil, iprodione, fenhexamid, fludioxonil, trifloxystrobin, boscalid). Thirty-five (2020) and …

Arkansas Wheat Performance Tests 2021-2022, J. F. Carlin, R. B. Morgan, R. D. Bond, D. E. Moon

Arkansas Agricultural Experiment Station Research Series

Wheat variety performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Agricultural Experiment Station, Department of Crop, Soil, and Environmental Sciences. The tests provide information to companies developing varieties and marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for small-grain producers. The tests are conducted at the Northeast Research and Extension Center at Keiser, the Vegetable Substation near Kibler, the Lon Mann Cotton Research Station near Marianna, the Pine Tree Research Station near Colt, and the Rohwer Research Station near Rohwer. Specific location …

Summaries Of Arkansas Cotton Research 2021, Fred Bourland

Arkansas Agricultural Experiment Station Research Series

While the basic growth and development of the cotton plant have not changed significantly in recent history, the business of cotton production is ever-changing. The last two years have seen us plant a crop just about as late as we thought possible, yet extended favorable conditions at season's end have been our salvation, helping to lead us to record yields. The economic environment over the last few years has been such that farmers need to produce record or near-record yields to advance. Unfortunately, production levels at the state yield average barely cover out-of-pocket expenses.

Great uncertainties exist for the upcoming …

Butterhead Lettuce Variety Performance Trial In A Hydroponic Nft System, Leah Worth, Mary Rogers, Amanda Reardon

Midwest Vegetable Trial Reports

Lettuce (Lactuca sativa L.) is a cool-season crop grown exclusively for fresh consumption. The intensive consumer demand of pre-packaged and living butterheads in the market today has been supported by the shift of soil production methods to soilless hydroponic systems. Hydroponic varietal and fertility recommendations for living butterhead optimization are limited to small-scale growers, however. To increase understanding of butterhead lettuce fertility preference, we examined two different water reservoir fertility concentrations across 12 replicated nutrient film technique (NFT) systems planted with six butterhead lettuce varieties. No differences were found between varieties grown in either recommended or high fertility concentrations, …

Zero Discharge Of Nutrient Solution To The Environment In A Soilless Greenhouse Cucumber Production System, Xiaotao Ding, Lizhong He, Rongguang Li, Tingting Qian, Hongmei Zhang, Haijun Jin, Jiawei Cui, Hong Wang, Qiang Zhou, Jun Zou, Dafeng Hui, Yuping Jiang, Kun He, Jizhu Yu

Biology Faculty Research

With the development of the economy and society, more attention is being paid to energy costs and the potential environmental pollution caused by vegetable cultivation. The aim of this study was to investigate the impacts of zero discharge of nutrient solutions on cucumber growth, leaf photosynthesis, and the yield and quality of cucumber under greenhouse conditions. The results show that zero discharge treatment did not change plant height, stem diameter, internode length, leaf area, net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr), and leaf relative chlorophyll content on the most measurement days. Only Pn …

Herbaceous Production Lost To Tree Encroachment In United States Rangelands, Scott L. Morford, Brady W. Allred, Dirac L. Twidwell Jr, Matthew O. Jones, Jeremy D. Maestas, Caleb P. Roberts, David E. Naugle

Department of Agronomy and Horticulture: Faculty Publications

1. Rangelands of the United States provide ecosystem services that benefit society and rural economies. Native tree encroachment is often overlooked as a primary threat to rangelands due to the slow pace of tree cover expansion and the positive public perception of trees. Still, tree encroachment fragments these landscapes and reduces herbaceous production, thereby threatening habitat quality for grassland wildlife and the economic sustainability of animal agriculture.

2. Recent innovations in satellite remote sensing permit the tracking of tree encroachment and the corresponding impact on herbaceous production. We analysed tree cover change and herbaceous production across the western United States …

From Free-Energy Profiles To Activation Free Energies, Johannes C. Dietschreit, Dennis J. Diestler, Andreas Hulm, Christian Ochsenfeld, Rafael Gómez-Bombarelli

Department of Agronomy and Horticulture: Faculty Publications

Given a chemical reaction going from reactant (R) to the product (P) on a potential energy surface (PES) and a collective variable (CV) discriminating between R and P, we define the free-energy profile (FEP) as the logarithm of the marginal Boltzmann distribution of the CV. This FEP is not a true free energy. Nevertheless, it is common to treat the FEP as the “free-energy” analog of the minimum potential energy path and to take the activation free energy, ΔF‡ _RP, as the difference between the maximum at the transition state and the minimum at R. We show that this …

A Yield Comparison Between Small-Plot And On-Farm Foliar Fungicide Trials In Soybean And Maize, Anabelle Laurent, Emily Heaton, Peter Kyveryga, David Makowski, Laila A. Puntel, Alison E. Robertson, Laura J. Thompson, Fernando Miguez

Department of Agronomy and Horticulture: Faculty Publications

Agronomic research provides management recommendations based on small-plot trials (SPTs) and on-farm trials (OFTs) with very different characteristics. SPTs are traditionally conducted at agricultural experiment stations by research institutes or universities, while OFTs are conducted under commercial-scale conditions and managed by farmers using their own equipment. Several researchers claimed that discrepancies could occur between these two types of trials, which can make the extrapolation of results from SPTs to the farm level difficult. In our study, we conducted an extensive comparison of small-plot and on-farm trials to analyze the effect of foliar fungicide application on maize and soybean yields. We …

Snp Discovery In Proso Millet (Panicum Miliaceum L.) Using Lowpass Genome Sequencing, Rituraj Khound, Guangchao Sun, Ravi V. Mural, James C. Schnable, Dipak K. Santra

Department of Agronomy and Horticulture: Faculty Publications

Domesticated ~10,000 years ago in northern China, Proso millet (Panicum miliaceum L.) is a climate-resilient and human health-promoting cereal crop. The genome size of this self-pollinated allotetraploid is 923 Mb. Proso millet seeds are an important part of the human diet in many countries. In the USA, its use is restricted to the birdseed and pet food market. Proso millet is witnessing gradual demand in the global human health and wellness food market owing to its health-promoting properties such as low glycemic index and gluten-free. The breeding efforts for developing improved proso millet cultivars are hindered by the …

Nebline, August/September 2022

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Nutrition Security: A New National Focus by Emily Gratopp

Recipe of the Month: Starwberry Smoothie and Freezer Pop by Emily Gratopp

Harvesting & Drying Herbs by Sarah Browning

Garden Guide: Things to Do This Month

Water Play Fun by Hayley Jackson

Controlling Poison Hemlock by Melissa Bartels

Summer Brings Singing Cicadas by Kait Chapman

4-H Announcements for Enrolled 4-H'ers or 4-H Volunteers

Lancaster County Super Fair, July 28-Aug. 6, 2022

4-H Will Livestream from the Fair! YouTube

Join 4-H!

Heart of 4-H Volunteer Award: Sonja Moore and Lancaster County Engineering Department

4-H Teen Council Invites New Members

4-H Council Golf …

Effects Of Shade Nets On Microclimatic Conditions, Growth, Fruit Yield, And Quality Of Eggplant (Solanum Melongena L.): A Case Study In Carnarvon, Western Australia, Giao N. Nguyen, Neil Lantzke, Andrew Van Burgel

Horticulture Research Articles

Carnarvon has a hot, semi-arid climate with high temperatures and solar radiation during spring–summer, which damages crops and limits the production season for the local vegetable industry. Protective cultivation is one of the promising approaches to mitigate these adverse weather conditions and avoid the resulting damage to vegetable crops. This study, which is part of the protected cropping research program for vegetable crops in Western Australia, was conducted to understand how the shade nets of a protective net house modify the microenvironment affecting the growth, physiology, and fruit yield of eggplants, a model vegetable crop. The eggplant crop was grown …

The Genetic Basis For Panicle Trait Variation In Switchgrass (Panicum Virgatum), Li Zhang, Alice Macqueen, Xiaoyu Weng, Kathrine D. Behrman, Jason Bonnette, John L. Reilley, Francis M. Rouquette, Philip A. Fay, Yanqi Wu, Felix B. Fritschi, Robert B. Mitchell, David B. Lowry, Arvid R. Boe, Thomas E. Juenger

Department of Agronomy and Horticulture: Faculty Publications

Key message: We investigate the genetic basis of panicle architecture in switchgrass in two mapping populations across a latitudinal gradient, and find many stable, repeatable genetic effects and limited genetic interactions with the environment. Abstract: Grass species exhibit large diversity in panicle architecture influenced by genes, the environment, and their interaction. The genetic study of panicle architecture in perennial grasses is limited. In this study, we evaluate the genetic basis of panicle architecture including panicle length, primary branching number, and secondary branching number in an outcrossed switchgrass QTL population grown across ten field sites in the central USA through multi-environment …

Characterization And Selection Of Hop Cultivars Adapted To Nebraska, Kristina Alas

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

Hop (Humulus lupulus L.) is an ingredient in the beer brewing industry that provides beer its flavor and aroma. High demand from the brewing industry has encouraged production outside of the traditional Pacific Northwest, the primary production region. Producers in the Midwest are attempting to grow cultivars adapted to the Pacific Northwest, but environmental differences have caused low yields and changes in secondary metabolite content. To aid producers, a regional breeding program was initiated to develop cultivars adapted to the Midwest. Success of any breeding program relies on the selection of genetically superior parents to generate progeny with the …

Mycorrhizae In Maize (Zea Mays L.) Cropping Systems Respond Differently To Nitrogen Fertilization Under Increasing Crop Rotational Diversity, Morgan R. Mcpherson

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

Arbuscular mycorrhizal fungi (AMF) remain a vital obligate symbiont of nearly all plants. It is well established that the symbiosis between AMF and host plant improves plant nutrient acquisition, alleviates abiotic and biotic environmental stressors, defends against plant pathogens, and contributes to overall plant fitness and productivity through modification of the soil habitat. Modifications include increased soil aggregation and stability, carbon sequestration through provision of fungal wall precursors to soil organic matter (SOM) formation, and enhanced nutrient cycling in the mycorrhizosphere. The goal of this dissertation was to assess how AMF respond to nitrogen (N) fertilization regimes in maize cropping …