Digital Commons Network^™

Assessment Of Grazing Procedures In The Evaluation Of Plant Breeding Material, D Real, I L. Gordon, J Hodgson

IGC Proceedings (1977-2023)

Four stocking densities (2, 3, 5 and 9 sheep/18 m2 for one hour) and two times of grazing (morning or evening) were imposed on a spaced plant nursery of nine red clover (Trifolium pratense L.) populations of varying growth habit, in order to optimize measurement of sheep grazing preference. Plant height, spread and leafiness were measured before and after each of three grazings. Sheep preference was viewed multivariately, using combined measurements of these plant characteristics. MANOVA revealed that the effect of stocking density was significant (P-0.05), but that of time of grazing was not. The plant, population and overall …

Developing Well Adapted Early To Midseason Cultivars Of Trifoiloum Subterraneum Ssp. Brachycalycinum, C T. De Koning, P G.H. Nichols, R L. Tuckwell, N Schubert

IGC Proceedings (1977-2023)

Development and selection of early to midseason cultivars of subterranean clover (Trifolium subterraneum L.) ssp. brachycalycinum has mostly involved the use of early generation selection nursery swards (F2-progeny method). Four sites were sown in the mid-North region of South Australia. At the end of 1995, the top 20 lines from each site had burrs (seed pods) sampled at random. The burr will proceed into the final early generation selection phase (1 - 2 years). Dependent on the site, many lines have out-performed the standard checkplot cultivar, Clare. High hardseed levels have also been incorporated into 1989 crossbreds.

Regeneration Of Somatic Hybrids Between Festuca Arundinacea Var. Glacescens And Lolium Multiflorum Lam., T Sasaki, T Hasegawa, S Ueda

IGC Proceedings (1977-2023)

Protoplasts derived from ten suspension cultures of tetraploid Festuca arundinacea var. glaucescens (2n = 4x = 28) and diploid Lolium multiflorum Lam. (2n = 2x =14) were fused to produce somatic hybrids. Regenerated green plants in three fusion combinations were identified as somatic hybrids because they showed characters that were peculiar to both Festuca arundinacea var. glaucescens (hairs on auricle) and Lolium multiflorum Lam. (root-fluorescence). Moreover, the hybrids also had a chromosome number of about forty two.

Breeding Morphogenetic Traits To Match Genotypes To Their Utilization, L Hazard, M Betin, M Ghesquiere

IGC Proceedings (1977-2023)

A divergent selection for lamina length was done from natural populations of perennial ryegrass. Tested in a multi-site experiment in France, the short-leaved perennial ryegrass was more productive under simulated grazing and less productive under infrequent cutting than the long-leaved perennial ryegrass. Matching cultivars to their management is possible by selecting for morphogenetic traits. However, our results suggest the range of adaptation to different managements of perennial ryegrass cultivars could be extended by increasing their phenotypic plasticity.

Improving Forage Productivity By Using Cytoplasmic Male Sterility Of Pearl Millet, A A. Younis, A H. Belal

IGC Proceedings (1977-2023)

Fourteen forage millet hybrids were produced by crossing 7 male fertile lines to 2 different lines of dwarf cytoplasmic male sterile (cms) lines of forage millet (Pennisetum americanum). Hybrids were evaluated with their male parents at the Giza experimental station in summer 1994. The evaluations included fodder yield traits and chemical composition. The objectives of the study were: 1 - to assess hybrid vigor, and 2 - to select the superior hybrids to be used in commercial production in Egypt. Present results showed that the 14 F1 hybrids and their male parents varied significantly in green and dry …

Protogynous Interval In Elephantgrass (Pennisetum Purpureum Schum.), A V. Pereira, R B. Barra, J C. Abreu, V De P. Freitas

IGC Proceedings (1977-2023)

A study was carried out to examine the protogyny duration in elephantgrass inflorescences. Nine accessions were selected, divided into three groups, according to early, intermediate or late flowering. From each cultivar, 10 panicles were sampled for evaluation. The criterion for estimating the duration of protogyny was the time interval (number of days) from the first visual detection of exserted stigmas up to the first visual appearance of open anthers (±5%). Duration of protogyny averaged 7.43±1.37 d, confirming that the species is protoginous. Late flowering accessions exhibited an average of 8.97 d for the duration of protogyny, which was significantly higher …

Evolution In Segregating Genotype Mixtures Of Subterranean Clover, P.G. H. Nichols, P S. Cocks

IGC Proceedings (1977-2023)

A complex segregating mixture of subterranean clover (Trifolium subterraneum L.), was sown in 1978 at Nabawa and Mt Barker, two contrasting sites in Western Australia. Seed harvested from both sites from 1980-1994 was grown out at Shenton Park in 1995, along with seed of the original mixture. Populations diverged markedly for mean days to first flowering (DFF) within three seasons. No further trends in mean DFF occurred in plants derived from the next 14 years, although standard deviation declined significantly in plants from Mt Barker. Between season differences in mean DFF were correlated with estimated growing season length at …

Prediction Of Seed Yield Of Festuca X Lolium Hybrids From The Nursery Mother Plants, C Mousset, L Hazard, M Ghesquiere

IGC Proceedings (1977-2023)

In order to develop commercial Festuca x Lolium hybrids, their seed production has to be improved. Seed yields of Festuca x Lolium progenies were assessed in dense plots. Prediction of those seed yields was based on the morphological observations done on spaced plants in the nursery of both mother plants and their progenies. The best prediction of the progeny seed yields is a linear regression on the stem density and the seed weight per inflorescence assessed on the mother plants.

Use Of Flow Cytometer In Breeding Festuca X Lolium Hybrids, M C. Kerlan, M Ghesquiere

IGC Proceedings (1977-2023)

Ploidy in various generic Lolium - Festuca progenies were assessed by flow cytometry and compared to conventional chromosome counting. In non-segregating triploid and tetraploid progenies, the cytometer estimated so accurately the level of plant ploidy that chromosomes counting would be no use. In segregant progenies, all the tetraploid plants according to the cytometer had effectively 28 chromosomes. Among the triploid and pentaploid plants detected by the cytometer, 40% of the plants were tetraploid. They represented only 29% of the progeny which must be counted. The flow cytometry can be used in routine interspecific breeding programmes. Conventional chromosome counting should be …

Persistency In Lolium X Festuca Hybrid Derivatives And Its Relationships With Flowering Traits, M Ghesquiere, C Mousset

IGC Proceedings (1977-2023)

Using amphiploid and backcrossed derivatives of Italian ryegrass x tall fescue hybrids, the paper emphasizes the interest of introgression vs amphiploidization in breeding for specific traits such as persistency or seed production from tall fescue or ryegrass resp. Persistency in amphiploid and Lolium-introgressed progenies were assessed in nursery together with variation of flowering traits. Persistency was found lower, on average, in introgressed progenies than in hybrid progenies but with enlarged variability within progeny suggesting possible advantageous rearrangements of fescue chromosomes. Although significantly associated, persistency in both populations was only very little affected by the variations in flowering traits such …

Field Evaluation Of Crown Rust In Annual Ryegrass Populations, G M. Prine

IGC Proceedings (1977-2023)

Crown rust (Puccinia coronata [Pers.] Cda.) is the most prevalent disease found on annual ryegrass (Lolium multiflorum L.) of the southeastern USA. Determination of crown rust resistance is difficult because of the erratic nature of infections at most locations. As crown rust is present at Gainesville, FL each year, a rust nursery was designed to evaluate rust resistance and susceptibility of annual ryegrass. Evaluation consists of periodic rust ratings of the seed crop and regrowth of part of each plot after cutting. Nursery results indicate the buildup of rust, including at the date of 90% heading (start of …

Selection Of Interspecific Hybrids Of Brachiaria-A Tropical Forage Grass, C B. Do Valle

IGC Proceedings (1977-2023)

The aim of the breeding program at the National Beef Cattle Research Center (CNPGC) of the Brazilian Corporation for Agricultural Research (EMBRAPA), is to produce vigorous apomictic hybrids with wide edaphic adaptation, good production and nutritive value combined with spittlebug (Homoptera:Cercopidea) resistance. Fiftysix superior hybrids were selected based on visual estimates of vigor, leafiness, tolerance to drought and natural spittlebug infestation in the field. These were characterized for mode of reproduction, spittlebug reaction under controlled conditions and for morphological diversity using nine selected traits. Multivariate analysis classified the population into seven groups where the hybrids were clearly intermediate in plant …

Mitochondrial Genome Polymorphism In Lolium Perenne, Y Shimamoto, Y Tominaga, M Sato, T Mikami

IGC Proceedings (1977-2023)

The restriction fragment length polymorphisms (RFLPs) of mitochondrial DNA (mtDNA) of perennial ryegrass (Lolium perenne L.) were investigated to elucidate the genetic relatedness among the 128 cultivars including diploid and tetraploid. Many patterns of RFLPs were observed and allowed assigning of the cultivars into the main eight haplotypes of mitochondrial genome relatedness. The American cultivars were classified into haplotype I and VIII which were remote at the mitochondrial genome from each other, the European ones were distributed to all haplotypes and the tetraploid ones were mostly assigned into the haplotype V. The assessment of mtDNA RFLPs may be a …

Inbreeding Of Some Populations In The Genus Agrostis L., Zorica Tomic, Gordana Surlan Momirovic, Dusica Delic, S Ostojic

IGC Proceedings (1977-2023)

This work presents some properties on produced inbred lines of the 5 best populations of 4 species of Agrostis for breeding purposes. The cultivars of forage grasses should meet a given aim for selection, which is the increasing dry matter and quality. The populations used in this research were the best ones for morphological and productive properties from a previous study. By the process of selfing there have been produced S1 offsprings which appeared to be quite superior in relation to open pollinated offspring from the mother plants. The obtained results were processed by multiple range regression analyses. According to …

The Effect Of Abscisic Acid On The Freezing Tolerance In Lolium Temulentum L., K Tase, H Fujii

IGC Proceedings (1977-2023)

This study was conducted to clarify the effect of abscisic acid (ABA) on the development of freezing tolerance in Lolium temulentum L. We compared the changes of freezing tolerance and endogenous ABA content by the ABA treatment with those by the hardening treatment. Exogenous ABA applications (7.5 x 10-5 M) increased freezing tolerance, but did not completely substitute for the hardening process. This treatment resulted in great increase in endogenous ABA content, as compared with the control or the hardening treatment. Since the relationship between endogenous ABA content and freezing tolerance was not parallel, it is considered that freezing tolerance …

Deep Learning Model For Personalized Prediction Of Positive Mrsa Culture Using Time-Series Electronic Health Records, Masayuki Nigo, Laila Rasmy, Bingyu Mao, Bijun Sai Kannadath, Ziqian Xie, Degui Zhi

Faculty, Staff and Student Publications

Methicillin-resistant Staphylococcus aureus (MRSA) poses significant morbidity and mortality in hospitals. Rapid, accurate risk stratification of MRSA is crucial for optimizing antibiotic therapy. Our study introduced a deep learning model, PyTorch_EHR, which leverages electronic health record (EHR) time-series data, including wide-variety patient specific data, to predict MRSA culture positivity within two weeks. 8,164 MRSA and 22,393 non-MRSA patient events from Memorial Hermann Hospital System, Houston, Texas are used for model development. PyTorch_EHR outperforms logistic regression (LR) and light gradient boost machine (LGBM) models in accuracy (AUROC

When And Why Ecological Systems Respond To The Rate Rather Than The Magnitude Of Environmental Changes, Karen C. Abbott

Faculty Scholarship

Ecologists and conservation biologists have become quite familiar with the concept of tipping points: abrupt changes in an ecosystem's state that occur after a period of relative stasis. Most of the familiar ecological examples of tipping points occur either because a once-stable state has lost stability, or the system has been subjected to a particularly large perturbation and transitions to an alternative stable state, distinct from the pre-perturbed state. A different class of tipping points, known as rate-induced tipping (or r-tipping) points, are likely present in many ecological communities but remain little known in the field. Rate-induced tipping occurs when …

Introduction Of Vegetative And Reproductive Characters Into Trifolium Repens By Interspecific Hybridisation, A H. Marshall, T P.T Michaelson-Yeates, M Meredith, D H. Hides

IGC Proceedings (1977-2023)

Interspecific hybridization between white clover (Trifolium repens L.) and ball clover (T.nigrescens) and Caucasian clover (T.ambiguum) is a means of improving the reproductive growth and persistency of T.repens. F1 hybrids between T.repens and T.nigrescens were produced without ovule culture and confirmed as true hybrids by chromosome counts, isoenzyme analysis and leaf markers. Their growth habit was generally intermediate between the two parents. After backcrossing to T.repens the BC1 and BC2 hybrids had more of the characteristics associated with T.repens though they retained some of the greater reproductive growth of …

Colchicine-Doubling Of Germinating Seedlings Of Interspecific Wildrye Hybrids, T A. Jones, D C. Nielson, H Jaussi

IGC Proceedings (1977-2023)

Colchicine has usually been applied to sterile clones of interspecific grass hybrids to restore fertility. However, when hybrids are partially fertile, colchicine can be applied to germinating seedlings. Four populations of Basin wildrye (Leymus cinereus) X beardless wildrye (L. triticoides) were treated with a 0.2% colchicine solution to double chromosome number from 4x=28 to 8x=56. Doubling percentage was 28, 33, 42, and 44% of all root-tips examined for the four populations. When plants without doubled sectors were discarded, doubling percentage increased to 56, 68, 78, and 78%. Plants with doubled sectors have been placed in crossing blocks …

Development Of An Integrated Workflow For Nucleosome Modeling And Simulations, Ran Sun

Doctoral Dissertations

Nucleosomes are the building blocks of eukaryotic genomes and thus fundamental to to all genetic processes. Any protein or drug that binds DNA must either cooperate or compete with nucleosomes. Given that a nucleosome contains 147 base pairs of DNA, there are approximately 4^147 or 10^88 possible sequences for a single nucleosome. Exhaustive studies are not possible. However, genome wide association studies can identify individual nucleosomes of interest to a specific mechanism, and today's supercomputers enable comparative simulation studies of 10s to 100s of nucleosomes. The goal of this thesis is to develop and present and end-to-end workflow that serves …

3d Pictorial Representations Of O2- And Ho2 Compared To Dft Results, Tzu-Hsiang Huang, Joseph D. Alia

Chemistry Publications

The Linnett Double Quartet (LDQ) (1) and Bohr Orbit Bonding (BOB) (2) methods were used to accurately represent the spin density distribution for superoxide (O2 -) and hydroperoxyl radical (HO2). These structural pictures were superimposed on the spin density plot produced by DFT. The Valency Interaction Formula (VIF) method (3) was also applied to these molecules and it matched the NBOs from NBO analysis of DFT results. The interaction between O2 - and H2O were analyzed and the stronger basicity of the beta-spin electrons of superoxide was identified by looking at the LDQ structure and confirmed with NBO analysis. The …

Plants Reduced Nitrous Oxide Emissions From A Northern Great Plains Saline/Sodic Soil, Sharon A. Clay, Thandiwe Nleya, David E. Clay, Deepak Joshi, Dwarika Bhattarai, Shin-Yi Marzano, Bhanu Prakash Petla

Agronomy, Horticulture and Plant Science Faculty Publications

The slowly establishing salt-tolerant perennial grasses reduced nitrous oxide (N2 O- N) emissions from saline/sodic soil compared to barren areas. Other salt-tolerant species may accelerate vegetative establishment and reduce N 2 O-N emissions. In a greenhouse study, barley (Hordeum vulgare L.), Florida broadleaf mustard (Brassica juncea L.), and Kernza intermediate wheatgrass [Thinopyrum intermedium (Host) Barkworth & D. R. Dewey] were grown for 63 days to compare shoot biomass and chemical composition, N 2 O-N emissions, and the soil microbiome between saline/sodic and productive (non-salt impacted) soils. Emissions were measured six times daily from 1 to 22 and 42 to 63 …

Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Articles
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Geologic Maps
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Cover Photographs
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Newspaper and Other Articles
Test-Hole Logs
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Geonotes
Abstracts
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Manuscripts Accepted (A), Submitted (S), or in Preparation (P)
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Geologic Maps-Nebraska
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Updated March 2024

Electronic Relaxation Mechanism Of 9-Methyl-2,6-Diaminopurine And 2,6-Diaminopurine-2′-Deoxyribose In Solution, Luis A. Ortiz-Rodríguez, Naishka E. Caldero-Rodríguez, Sourav Kanti Seth, Karitza Díaz-González, Carlos E. Crespo-Hernández

Faculty Scholarship

Prolonged ultraviolet exposure results in the formation of cyclobutane pyrimidine dimers (CPDs) in RNA. Consequently, prebiotic photolesion repair mechanisms should have played an important role in the maintenance of the structural integrity of primitive nucleic acids. 2,6-Diaminopurine is a prebiotic nucleobase that repairs CPDs with high efficiency when incorporated into polymers. We investigate the electronic deactivation pathways of 2,6-diaminopurine-2′-deoxyribose and 9-methyl-2,6-diaminopurine in acetonitrile and aqueous solution to shed light on the photophysical and excited state properties of the 2,6-diaminopurine chromophore. Evidence is presented that both are photostable compounds exhibiting similar deactivation mechanisms upon the population of the S1(ππ* La) state …

Field Research Report: Results From The Enreec Vri Field For The 2021, 2022, And 2023 Crop Seasons, Derek M. Heeren, Ali T. Mohammed, Eric Wilkening, Christopher M. U. Neale, Alan L. Boldt, Ankit Chandra, Precious Nneka Amori, Ivo Z. Goncalves, Yeyin Shi, Guillermo R. Balboa

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Long-term irrigation management research has been conducted from 2014 to 2023 for corn and soybean at the Eastern Nebraska Research, Extension, and Education Center (ENREEC) Variable Rate Irrigation (VRI) Field located in subhumid east-central Nebraska (in the Lower Platte North Natural Resources District). The objective of this report was to present the overall results from the VRI Field for 2021 to 2023. Across the three growing seasons, there were the following irrigation treatments: Best Management Practice (BMP), 50% BMP, 125% BMP, rainfed, Spatial ET Modeling Interface (SETMI), SDD1, SDD2, machine-learning-based Cyber-Physical System (CPS), a student team recommended rate, and industry …

Development Of Mass Spectrometric Glycan Characterization Tags Using Acid-Base Chemistry And/Or Free Radical Chemistry, Rayan Murtada, Shane Finn, Jinshan Gao

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Despite recent advances in glycomics, glycan characterization still remains an analytical challenge. Accordingly, numerous glycan-tagging reagents with different chemistries were developed, including those involving acid-base chemistry and/or free radical chemistry. Acid-base chemistry excels at dissociating glycans into their constituent components in a systematic and predictable manner to generate cleavages at glycosidic bonds. Glycans are also highly susceptible to depolymerization by free radical processes, which is supported by results observed from electron-activated dissociation techniques. Therefore, the free radical activated glycan sequencing (FRAGS) reagent was developed so as to possess the characteristics of both acid-base and free radical chemistry, thus generating information-rich …

Automated Tree Mortality Detection Using Ubiquitously Available Public Data, Michael T. Huggins

Master's Theses

Understanding the dynamic interplay between fire severity, topography, and tree mortality, is crucial for predicting future forest dynamics and enhancing resilience against climate change-induced wildfire regimes. This thesis develops a multi-sensor approach for automated estimation of tree mortality, then applies it to examine trends in tree mortality over a six-year period across a fire affected study site in the Trinity River basin in Northern California. The Random Forest model uses publicly available USGS 3D Elevation Program Lidar (3DEP) and NAIP imagery as inputs and is likely to be easily adaptable to other landscapes. The model had a Receiver Operating Characteristic …

Forging The Future: Strategic Approaches To Quantum Ai Integration For Industry Transformation, Meng Leong How, Sin Mei Cheah

CCX Research

The fusion of quantum computing and artificial intelligence (AI) heralds a transformative era for Industry 4.0, offering unprecedented capabilities and challenges. This paper delves into the intricacies of quantum AI, its potential impact on Industry 4.0, and the necessary change management and innovation strategies for seamless integration. Drawing from theoretical insights and real-world case studies, we explore the current landscape of quantum AI, its foreseeable influence, and the implications for organizational strategy. We further expound on traditional change management tactics, emphasizing the importance of continuous learning, ecosystem collaborations, and proactive approaches. By examining successful and failed quantum AI implementations, lessons …

Meta-Interpretive Learning With Reuse, Rong Wang, Jun Sun, Cong Tian, Zhenhua Duan

Research Collection School Of Computing and Information Systems

Inductive Logic Programming (ILP) is a research field at the intersection between machine learning and logic programming, focusing on developing a formal framework for inductively learning relational descriptions in the form of logic programs from examples and background knowledge. As an emerging method of ILP, Meta-Interpretive Learning (MIL) leverages the specialization of a set of higher-order metarules to learn logic programs. In MIL, the input includes a set of examples, background knowledge, and a set of metarules, while the output is a logic program. MIL executes a depth-first traversal search, where its program search space expands polynomially with the number …

Health And Safety Plan (Hasp) Butte Priority Soils Operable Unit, Woodard & Curran

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.