Life Sciences Commons^™

The Relative Contribution Of The Blue Crab (Callinectes Sapidus) To Periwinkle Snail (Littoraria Irrorata) Predation Mortality In The Lower Salt Marsh Intertidal Of Northeast Florida, Amanda Paige Small

UNF Graduate Theses and Dissertations

In top-down regulation of ecological communities, predation of grazers is critical for maintaining the presence and growth of essential vegetation. The periwinkle snail (Littoraria irrorata) is a ubiquitous grazer in Atlantic salt marshes that can defoliate patches of Spartina alterniflora when populations are extremely dense. On the east coast of Florida, multiple predators could contribute to periwinkle population control maintaining this critical habitat. This study aimed to determine if the blue crab (Callinectes sapidus) is the primary predator of periwinkle snails in the salt marsh lower intertidal. Tethering was utilized to assess if periwinkle mortality is …

Benthic Microalgae Response To A Warming Climate And Shift In Foundational Vegetation Species In A Saltmarsh-Mangrove Ecotone, Gabriela Canas

UNF Graduate Theses and Dissertations

The ecotone in Northeast Florida is experiencing rapid change as mangroves begin to encroach northward into saltmarsh dominated coastal wetlands. This is especially prevalent within the boundaries of the Guana Tolomato Matanzas National Estuarine Research Reserve where studies are attempting to understand the consequences of more mangroves. Although we are beginning to understand some of the implications of this shift in dominant vegetation, the true effects and the accompanying sustained climatic warming effects on the resilience of wetland habitats and their associated communities remains unknown. Primary producers such as benthic microalgae (BMA) are important food sources in both mangrove and …

Weak Olfactory Preferences Of The Gall Midge Asphondylia Borrichiae, Associated Fungal Endophytes And Implications On Gene Flow And Host Range Expansion, Frances S. Nagle

UNF Graduate Theses and Dissertations

Asphondylia borrichaie is a small fly (Diptera: Cecidomyiidae) that is currently undergoing host-associated sympatric divergence. Asphondylia borrichaie is an ambrosia galler, these insects utilize a host plant for oviposition, but its offspring also rely on a symbiotic fungus (or fungal community) to promote the formation of the gall as well as serve as a food source for the developing larvae. Previous studies indicate that A. borrichaie consists of two host- associated populations based on its original host plant Borrichia frutescens (Asterales: Asteraceae), and another one from the two Iva species (I. frutescens (Asterales: Asteraceae) and I. imbricata …

Characterization Of A Scalloped Hammerhead (Sphyrna Lewini) Nursery Habitat In Portions Of The Atlantic Intracoastal Waterway, Bryanna N. Wargat

UNF Graduate Theses and Dissertations

The scalloped hammerhead shark (Sphyrna lewini) worldwide population has been in sharp decline, and they are currently listed as a globally critically endangered species by the IUCN. This warrants a need to identify and protect critical habitats for the species, such as nurseries, which promote stable populations. A section of the Tolomato River, in northeastern Florida, has shown to host large and consistent numbers of young of year scalloped hammerhead sharks. This gave cause to determine whether this portion of the Atlantic Intracoastal Waterway (ICW) serves as a nursery habitat for the species and to understand how the …

An Investigation Of The Role Of Basigin-Variant-1 In The Immune Response Within The Retina, Abigail D. Tompa

UNF Graduate Theses and Dissertations

The neural retina is considered an immune privileged area, in that the eye attempts to suppress the inflammatory response to preserve vision. If there is damage to the blood-retina barrier, such as in diabetes or macular degeneration, it is possible for monocytes to travel out of the blood vessels and into the retina. While studying retinoblastoma, a research group determined that the protein, Basigin, through its extracellular domain, elicits an immune response by enhancing transcription of the pro-inflammatory cytokine interleukin-6 (IL-6). Basigin is cell adhesion molecule that belongs to the immunoglobulin superfamily. The Basigin gene has two main transcripts, that …

Regeneration Patterns In Silvicultural Openings Of Western Great Lakes Northern Hardwood Forests 15-24 Years Post-Harvest, Matthew S. Vandermolen

Dissertations, Master's Theses and Master's Reports

In managed northern hardwood forests, successful forest regeneration can depend on the application of silvicultural methods tailored to stand-specific recruitment limitations. The objective of this research is to develop a deeper understanding of the factors that interfere with tree regeneration at three long-term, well-replicated experimental canopy gap studies in the upper Great Lakes region, USA. Chapter 2 examines regeneration at a hemlock canopy gap study 18 years post-harvest that included deer exclosures and a gradient of gap sizes. Chapter 3 investigates the spatial patterns of low-density regeneration along gradients of gap size and different levels of legacy-tree retention at two …

Functional Genetic Approaches To Provide Evidence For The Role Of Toolkit Genes In The Evolution Of Complex Color Patterns In Drosophila Guttifera, Mujeeb Olushola Shittu

Dissertations, Master's Theses and Master's Reports

Toolkit genes are set of genes that orchestrate the development of basic body plan of animals, and they are highly conserved in all animals. The co-option of the toolkit genes into the pigmentation pathway has led to the evolution of novel species. This study focuses on understanding how the complex color patterns in animals develop by using the Drosophila species in the quinaria group as models. We developed an mRNA in situ hybridization (ISH) protocol, which allowed us to study gene expression patterns in the abdomen of developing pupae of non-model Drosophila species (Chapter 2). Through ISH, we found that …

Impact Of Hemodynamic Vortex Spatial And Temporal Characteristics On Analysis Of Intracranial Aneurysms, Kevin W. Sunderland

Dissertations, Master's Theses and Master's Reports

Subarachnoid hemorrhage is a potentially devastating pathological condition in which bleeding occurs into the space surrounding the brain. One of the prominent sources of subarachnoid hemorrhage are intracranial aneurysms (IA): degenerative, irregular expansions of area(s) of the cerebral vasculature. In the event of IA rupture, the resultant subarachnoid hemorrhage ends in patient mortality occurring in ~50% of cases, with survivors enduring significant neurological damage with physical or cognitive impairment. The seriousness of IA rupture drives a degree of clinical interest in understanding these conditions that promote both the development and possible rupture of the vascular malformations. Current metrics for the …

Statistical Methods In Genetic Studies, Cheng Gao

Dissertations, Master's Theses and Master's Reports

This dissertation includes three Chapters. A brief description of each chapter is organized as follows.

In Chapter 1, we proposed a new method, called MF-TOWmuT, for genome-wide association studies with multiple genetic variants and multiple phenotypes using family samples. MF-TOWmuT uses kinship matrix to account for sample relatedness. It is worth mentioning that in simulations, we considered hidden polygenic effects and varied the proportion of variance contributed by it to generate phenotypes. Simulation studies show that MF-TOWmuT can preserve the type I error rates and is more powerful than several existing methods in different simulation scenarios, MFTOWmuT is also quite …

Spatial And Temporal Comparison Of Persistent Organic Pollutants In The Boardman River, Collin Diedrich

Dissertations, Master's Theses and Master's Reports

Dam removal is a critical part of river and stream remediation projects around the world. Frequently dams are associated with impoundment ponds containing sediments that can act as a sink of various persistent organic pollutants (POPs) that can pose risks for human and aquatic wildlife. In this study, we deployed semi-permeable membrane devices (SPMDs) at multiple locations along a 25-mile stretch of the Boardman River in Traverse City Michigan to passively sample POP concentrations in this area that has recently undergone dam and impoundment pond sediment removal. Concentrations of polychlorinated biphenyl (PCB), di-chloro-diphenyl-trichloroethane (DDT) and cyclodiene compounds were in the …

Denitrification And Nitrogen Fixation Commonly Co-Occur But Rates Vary Throughout The Year And In Different Environments, Kevin Nevorski

Dissertations, Master's Theses and Master's Reports

Denitrification and nitrogen fixation are nitrogen cycling processes that can occur simultaneously in streams but are rarely studied together. The overarching goal of this dissertation was to quantify temporal and spatial variation of these processes in streams across the USA, characterize the environmental drivers of that variation, and determine the role that denitrification plays in the carbon cycle. To characterize temporal variation in these processes, a 2-year study in the Pilgrim River in Michigan’s Upper Peninsula found no difference in rates among seasons but high day-to-day variation in rates of both processes (maximum daily change 4,390 μg N/m²/hr …

The Effect Of Nutrition On Longevity And Fertility In Diverse Drosophila: A Tor-Mediated Process, Tessa E. Steenwinkel

Dissertations, Master's Theses and Master's Reports

Nutrition and growth are strongly linked, but not much is known about how nutrition leads to growth. To understand the connection between nutrition through diet, growth and/or proliferation, we need to study the phenotypes resulting from the activation and inhibition of central metabolic pathways. Here I use the model organism Drosophila melanogaster (D. mel.) and three non-model Drosophila species with different dietary needs, Drosophila guttifera (D. gut.), Drosophila deflecta (D. def.), and Drosophila tripunctata (D. tri.), to study the effects of dietary amino acid availability in these diverse flies on fecundity and …

Applications Of Machine Learning In Microbial Forensics, Ryan B. Ghannam

Dissertations, Master's Theses and Master's Reports

Microbial ecosystems are complex, with hundreds of members interacting with each other and the environment. The intricate and hidden behaviors underlying these interactions make research questions challenging – but can be better understood through machine learning. However, most machine learning that is used in microbiome work is a black box form of investigation, where accurate predictions can be made, but the inner logic behind what is driving prediction is hidden behind nontransparent layers of complexity.

Accordingly, the goal of this dissertation is to provide an interpretable and in-depth machine learning approach to investigate microbial biogeography and to use micro-organisms as …

Evaluating Long-Term Growth And Yield In Upper Great Lakes Region Northern Hardwoods Cutting Trials, Maeve Draper

Dissertations, Master's Theses and Master's Reports

Common partial cutting management methods in Lake States hardwoods include both selection management and diameter-limit cuttings. Single-tree selection in particular is a widely prescribed silvicultural system in northern hardwoods and has an established history of use throughout the entire range of the forest type. Using data from two historic silvicultural studies, long-term comparison of single-tree selection methods and other partial cutting practices in northern hardwoods reveals that single-tree selection to higher residual basal areas, as widely applied in Great Lakes northern hardwood forests, is inferior using financial and volume yield criteria. Alternatives that remove more of the larger trees appear …

Metagenomic Identification And Classification Of The Mercury-Methylating Gene Hgca In Response To Water Table And Plant Functional Group Manipulations In Peat Soil, Madeline Peterson

Dissertations, Master's Theses and Master's Reports

Methyl-mercury (MeHg) is a potent neurotoxin that threatens the health of humans and wildlife alike. Climate warming threatens to shift regional precipitation and climate regimes in peatland environments, which could destabilize northern peatlands and accelerate both Hg release from soil and MeHg production. Peatlands are among the leading hotspots for MeHg, yet little is known about the community composition or functional relationship of mercury-methylating microbes in response to varying environmental conditions. The recognized mercury-methylating genes responsible for this activity are the obligatory gene pair hgcA and hgcB. Metagenomic data from the full-factorial peatland mesocosm experiment PEATcosm was obtained to …

Construction And Analysis Of Genetic Regulatory Networks With Rna-Seq Data From Arabidopsis Thaliana, Tessa Kriz

Dissertations, Master's Theses and Master's Reports

Reconstruction of gene regulatory networks (GRNs) is a fundamental aspect of genetic engineering and provides a deeper understanding of the biological processes of an organism. Two methods were implemented to reconstruct the gene regulatory networks of Arabidopsis thaliana under two treatments: methyl jasmonate (MeJa) and salicylic acid (SA). The Joint Reconstruction of multiple Gene Regulatory Networks (JRmGRN) method was utilized to construct a joint network for identifying hub genes common to both conditions in addition to networks specific to each condition. The Differential Network Analysis with False Discover Rate Control method constructed a network of connections unique to only one …

24andmore: Using Genome-Wide Snps To Investigate The Genetic Diversity Of Iowa Walleye (Sander Vitreous) Broodstock, Rachel Ann Mcdonnell

Dissertations and Theses @ UNI

The stocking of Sander vitreus in Iowa waterbodies is one of the primary tools used by the Iowa Department of Natural Resources (DNR) to ensure healthy populations for enjoyable fishing experiences. A substantial amount of time and money goes into this effort, so stocking efficiency is vital. Knowledge of genetic diversity contained in the broodstock increases this efficiency by having a better understanding of which strain will survive and contribute to the fishery in certain environments. The objective of this study is to investigate the genetic diversity of Iowa S. vitreus broodstock to identify genetic ancestry and quantify the genetic …

In Silico And In Vitro Tudies For Identification Of Novel Egfr Tyrosine Kinase Inhibitors, Duangjai Todsaporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Epidermal growth factor receptor (EGFR) has been identified as a promising target in the treatment of non-small cell lung cancer (NSCLC). Mutations, including L858R/T790M double and L858R/T790M/C797S triple mutations, in the TK domain of EGFR have been linked to the severity of several cancers, especially NSCLC. A combination of comprehensive molecular modeling and in vitro kinase inhibition assay was used to unravel the mutational effects of EGFR on the susceptibility of five commercial drugs (erlotinib, gefitinib, afatinib, dacomitinib, and osimertinib) from each generation of EGFR in comparison with the wild-type EGFR. The binding affinity of five-FDA-approved drugs towards the L858R/T790M …

Arthropod Fauna Of Plains Pocket Gopher (Geomys Bursarius) Burrow Systems, Brett Lyle Gourley

Dissertations and Theses @ UNI

Pocket gophers are among the most asocial mammals, living a solitary existence except for mating and the rearing of offspring. They create expansive burrow systems underground while foraging for food and rarely surfacing above ground. As gophers burrow, excess soil is pushed to the surface or placed in older tunnels. This behavior creates a cave-like ecosystem where pocket gophers and associated arthropods live.

Few studies have been done on the arthropod fauna cohabitating with pocket gophers in these burrows. Most of these studies have focused on a family of arthropods over several sites. Many have focused on the southern United …

An Investigation On The Regulation Of The Tweak–Fn14–Nf-Kb Pathway, Jawahar Khetan

Doctoral Dissertations

“Dysregulation of inflammatory pathways is strongly implicated in cancers and autoimmune diseases. The most consequential of these pathways involves the nuclear translocation of NF-kB, a transcription factor that induces the transcription of multiple proteins associated with cell survival, inflammation, proliferation and death. It is activated when the fibroblast growth factor-inducible 14 kDa protein (Fn14), a trimeric receptor recruits its ligand, TWEAK. Studies have shown that Fn14 is over-expressed in many tumors, the aggressiveness of which is often correlated with the degree of upregulation. Furthermore, TWEAK-Fn14 activation has been shown to result in persistent NF-kB activation. Using a mechanistic model of …

Critical Behavior In Evolutionary And Population Dynamics, Stephen Walter Ordway

Doctoral Dissertations

“This study is an exploration of phase transition behavior in evolutionary and population dynamics, and techniques for predicting population changes, across the disciplines of physics, biology, and computer science. Under the looming threat of climate change, it is imperative to understand the dynamics of populations under environmental stress and to identify early warning signals of population decline. These issues are explored here in (1) a computational model of evolutionary dynamics, (2) an experimental system of decaying populations under environmental stress, and (3) a machine learning approach to predict population changes based on environmental factors. Through the lens of critical phase …

Exposure Assessment Of Emerging Contaminants: Rapid Screening And Modeling Of Plant Uptake, Majid Bagheri

Doctoral Dissertations

"With the advent of new chemicals and their increasing uses in every aspect of our life, considerable number of emerging contaminants are introduced to environment yearly. Emerging contaminants in forms of pharmaceuticals, detergents, biosolids, and reclaimed wastewater can cross plant roots and translocate to various parts of the plants. Long-term human exposure to emerging contaminants through food consumption is assumed to be a pathway of interest. Thus, uptake and translocation of emerging contaminants in plants are important for the assessment of health risks associated with human exposure to emerging contaminants. To have a better understanding over fate of emerging contaminants …

รอยสึกบนฟันกรามของสัตว์เลี้ยงลูกด้วยนมในวงศ์ย่อย Caprinae จากสมัยไพลสโตซีนและปัจจุบันของประเทศไทย, จักรีทิพย์ อิศรางกูร ณ อยุธยา

Chulalongkorn University Theses and Dissertations (Chula ETD)

สัตว์เลี้ยงลูกด้วยนมในวงศ์ย่อย Caprinae สามชนิด ได้แก่ เลียงผาใต้ (Capricornis sumatraensis) กวางผาจีน (Naemorhedus griseus) และกวางผาหิมาลัย (Naemorhedus goral) ปรากฎหลักฐานการกระจายตัวในประเทศไทยสมัยไพลสโตซีน อย่างไรก็ตาม ปัจจุบันกวางผาหิมาลัยได้สูญพันธุ์ไปจากประเทศไทยแล้ว เพื่อบ่งบอกนิเวศวิทยที่เปลี่ยนแปลงไปในอดีตจนถึงปัจจุบันของสัตว์กลุ่มนี้ รอยสึกบนฟันกรามจึงถูกนำมาใช้เพื่อการศึกษาอาหาร รููปแบบการกินอาหาร และนิเวศวิทยาบรรพกาลของสัตว์ในวงศ์ย่อย Caprinae ผู้วิจัยศึกษาตัวอย่างจาก 4 แหล่งขุดค้นซากดึกดำบรรพ์ในประเทศไทย ที่มีอายุระหว่างสมัยไพลสโตซีนตอนกลางถึงตอนปลาย ได้แก่ ถ้ำผาบ่อง, บ้านโคกสูง, ถ้ำวิมานนาคินทร์ และเพิงผาถ้ำลอด รวมไปถึงตัวอย่างปัจจุบันจากพิพิธภัณฑ์และเขตรักษาพันธุ์สัตว์ป่าทั้งหมด 10 แห่ง โดยเก็บข้อมูลค่าดัชนีความสูงตัวฟัน (hypsodonty index: HI), รอยสึกระดับ mesowear I และ II, และรอยสึกระดับ microwear จากฟันกราม ผลการศึกษาพบว่า รอยสึกระดับ mesowear และค่า HI บ่งชี้ว่าเลียงผาและกวางผาทั้งในปัจจุบันและไพลสโตซีนกินใบไม้และหญ้า โดยเลียงผาใต้มีแนวโน้มการกินใบไม้มากกว่าชนิดอื่น ผลการศึกษารอยสึกระดับ microwear จากทั้งตัวอย่างปัจจุบันและไพลสโตซีนพบว่า เลียงผาใต้กินใบไม้อ่อนนุ่ม ขณะที่กวางผาจีนและกวางผาหิมาลัยกินใบไม้และหญ้าที่มีความแข็ง เมื่อพิจารณาผลการศึกษาที่ได้ร่วมกับค่าไอโซโทปเสถียรของธาตุคาร์บอนจากงานวิจัยก่อนหน้า อาจกล่าวได้ว่า เลียงผาใต้ในสมัยไพลสโตซีนกินใบไม้อ่อนนุ่มทั้งประเภท C3, C3/C4, และ C4 อยู่อาศัยได้ทั้งป่าทึบและทุ่งหญ้า กวางผาจีนในสมัยไพลสโตซีนกินใบไม้และหญ้าประเภท C4 ที่มีความแข็ง อาศัยในทุ่งหญ้าเปิด สำหรับกวางผาหิมาลัยในสมัยไพลสโตซีนกินใบไม้และหญ้าประเภท C4 หรือ C3/C4 และอาศัยในทุ่งหญ้าเปิด ผลการศึกษาสามารถสรุปแนวโน้มการเปลี่ยนแปลงนิเวศวิทยาของสายพันธุ์เลียงผาและกวางผาได้ว่า เลียงผาและกวางผาสมัยไพลสโตซีนอาศัยในทุ่งหญ้าเปิดมากกว่าประชากรในปัจจุบัน ซึ่งอาจเป็นผลจากการเปลี่ยนแปลงของสภาพแวดล้อมจากอดีตจนถึงปัจจุบัน และการรุกรานของมนุษย์ตั้งแต่สมัยไพลสโตซีนที่ส่งผลให้จำนวนประชากรลดลง

ความหลากหลายทางพันธุกรรมของยีนสร้างโปรตีน Pfs25 ของเชื้อมาลาเรีย Plasmodium Falciparum ในประเทศไทย, พรปวีณ์ สุขพงษ์ไทย

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pfs25 เป็นโปรตีนที่พบได้บนเยื่อหุ้มเซลล์ของเชื้อมาลาเรีย Plasmodium falciparum ในระยะ sexual stage และเป็นหนึ่งในแอนติเจนของวัคซีนสำหรับป้องกันการติดต่อของโรคมาลาเรียชนิด transmission blocking vaccine (TBV) วัคซีนชนิดนี้สร้างจากแอนติเจน Pfs25 ของเชื้อมาลาเรีย P. falciparum สายพันธุ์ 3D7 และได้รับการพัฒนาอย่างต่อเนื่องจนถึงขั้นตอนทดสอบทางคลินิก อย่างไรก็ดี การศึกษาความหลากหลายของยีน Pfs25 ในประชากร P. falciparum ในธรรมชาติทั้งในประเทศไทยและพื้นที่อื่น ๆ มีอยู่อย่างจำกัด ดังนั้น วิทยานิพนธ์เรื่องนี้มีวัตถุประสงค์เพื่อศึกษาความหลากหลายทางพันธุกรรมของยีน Pfs25 ของ P. falciparum ในประเทศไทยและพื้นที่อื่น ๆ ทั่วโลก ตัวอย่างประกอบด้วยลำดับนิวคลีโอไทด์ของ Pfs25 ของ P. falciparum ในประเทศไทยจำนวน 83 ตัวอย่าง และข้อมูลจากฐานข้อมูล GenBank และ PlasmoDB จำนวน 224 ตัวอย่าง ซึ่งการศึกษานี้ได้รวบรวมและสร้างฐานข้อมูลนิวคลีโอไทด์ขึ้นเป็นครั้งแรก ทำการศึกษาความหลากหลายด้วยการวิเคราะห์ทาง พันธุศาสตร์ประชากร ผลการศึกษาพบว่า Pfs25 ในประชากรเชื้อมาลาเรีย P. falciparum ทั่วโลกมีจำนวน 11 haplotype ในจำนวนนี้ พบในประเทศไทยจำนวน 7 haplotype (H) โดย H2 เป็น haplotype ที่พบมากที่สุดในประชากรเชื้อมาลาเรียในทวีปเอเชีย ส่วน H1 พบมากที่สุดในประชากรในทวีปแอฟริกาและทวีปอเมริกากลางและอเมริกาใต้ การวิเคราะห์ด้วย Fst แสดงให้เห็นว่า การกระจายของ haplotype ทั้งหมดแตกต่างกันตามแต่ละทวีป แสดงว่า เชื้อมาลาเรีย P. falciparum แบ่งออกเป็น 3 ประชากรย่อย ๆ ตามพื้นที่ คือ ประชากรในทวีปเอเชีย ทวีปแอฟริกา และทวีปอเมริกากลางและอเมริกาใต้ นอกจากนี้ เมื่อวิเคราะห์ความสัมพันธ์ของ haplotype ด้วย …

Does Biochar Improve All Soil Ecosystem Services?, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

Biochar is considered to sequester C and deliver other soil ecosystem services, but an overview that synthesizes the current knowledge of biochar implications on all essential soil ecosystem services is difficult to find in the ample biochar literature. Most previous research and review articles on this topic focused on a single ecosystem service and did not integrate all essential soil ecosystem services. This overview paper (1) synthesizes the impacts of biochar on water and wind erosion, C sequestration, soil water, nutrient leaching, soil fertility, crop yields, and other soil ecosystem services based on published literature and (2) highlights remaining research …

Intervention Of Climate-Smart Practices In Wheat Under Rice-Wheat Cropping System In Nepal, Janma Jaya Gairhe, Mandeep Adhikari, Deepak Ghimire, Arun Khatri-Chhetri, Dinesh Panday

Department of Agronomy and Horticulture: Faculty Publications

Besides a proper agronomic management followed by Nepalese farmers, wheat (Triticum aestivum L.) production has been severely affected by changing climate. There are many interventions, including climate-smart practices, to cope with this situation and possibly enhance crop and soil productivity. Field experiments were set up in a randomized complete block design with six treatments (TRT) with four replications in three locations (LOC) during wheat-growing seasons in Nepal from 2014 to 2016. Treatments included (i) Controlled Practice (CP), (ii) Improved Low (IL), (iii) Improved High (IH), (iv) Climate Smart Agriculture Low (CSAL), (v) Climate Smart Agriculture Medium (CSAM), and (vi) …

Effect Of Foliar Micronutrients (B, Mn, Fe, Zn) On Maize Grain Yield, Micronutrient Recovery, Uptake, And Partitioning, Zachary P. Stewart, Ellen T. Paparozzi, Charles S. Wortmann, Prakash Kumar Jha, Charles A. Shapiro

Department of Agronomy and Horticulture: Faculty Publications

Timing of micronutrient demand and acquisition by maize (Zea Mays L.) is nutrient spe‐ cific and associated with key vegetative and reproductive growth stages. The objective of this study was to determine the fate of foliar‐applied B, Fe, Mn, Zn, and Fe/Zn together, evaluate the effect of foliar micronutrients applied at multiple rates and growth stages on maize grain yield, and deter‐ mine their apparent nutrient recovery efficiency (ANR). Five Randomized Complete Block Design (RCBD) experiments were conducted in 2014 and 2015 at five locations across Nebraska. Total dry matter was collected at 5–6 stages, and separated into leaves, stalk, …

Genomic Resources In Plant Breeding For Sustainable Agriculture, Mahendar Thudi, Rajeev K. Varshney, James C. Schnable

Department of Agronomy and Horticulture: Faculty Publications

Climate change during the last 40 years has had a serious impact on agriculture and threatens global food and nutritional security. From over half a million plant species, cereals and legumes are the most important for food and nutritional security. Although systematic plant breeding has a relatively short history, con- ventional breeding coupled with advances in technology and crop management strategies has increased crop yields by 56 % globally between 1965− 85, referred to as the Green Revolution. Nevertheless, increased demand for food, feed, fiber, and fuel necessitates the need to break existing yield barriers in many crop plants. In …

Responses Of Soil Surface Greenhouse Gas Emissions To Nitrogen And Sulfur Fertilizer Rates To Brassica Carinata Grown As A Bio-Jet Fuel, Dwarika Bhattarai, Gandura O. Abagandura, Thandiwe Nleya, Sandeep Kumar

Department of Agronomy and Horticulture: Faculty Publications

Carinata (Brassica carinata A. Braun), a non-food oilseed crop and an alternative bio-jet fuel feedstock, has received attention for its potential as a low-input option for production in the semi-arid region of the Northern Great Plains of the United States. Research addressing the impacts of nitrogen (N) and sulfur (S) fertilizers on soils and greenhouse gas (GHG; CO2, N2O, and CH4) emissions from carinata production are limited. Thus, objective of this study was to evaluate the impact of different rates of N and S fertilizers applied to carinata on soil properties and GHG emissions. Field experiments were conducted in 2017 …

Soil Erosion Modelling: A Global Review And Statistical Analysis, Pasquale Borrelli, Panos Panagos, Dinesh Panday, 64 More Co-Authors

Department of Agronomy and Horticulture: Faculty Publications

To gain a better understanding of the global application of soil erosion prediction models, we comprehensively reviewed relevant peer-reviewed research literature on soil-erosion modelling published between 1994 and 2017.We aimed to identify (i) the processes and models most frequently addressed in the literature, (ii) the regions within which models are primarily applied, (iii) the regions which remain unaddressed and why, and (iv) how frequently studies are conducted to validate/evaluate model outcomes relative to measured data. To perform this task, we combined the collective knowledge of 67 soil-erosion scientists from 25 countries. The resulting database, named ‘Global Applications of Soil Erosion …