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Articles 5311 - 5340 of 302422

Full-Text Articles in Physical Sciences and Mathematics

Environmental Dna Metabarcoding Of Pan Trap Water To Monitor Arthropod-Plant Interactions, Joshua H. Kestel, David L. Field, Philip W. Bateman, Nicole E. White, Karen L. Bell, Paul Nevill Mar 2024

Environmental Dna Metabarcoding Of Pan Trap Water To Monitor Arthropod-Plant Interactions, Joshua H. Kestel, David L. Field, Philip W. Bateman, Nicole E. White, Karen L. Bell, Paul Nevill

Research outputs 2022 to 2026

Globally, the diversity of arthropods and the plants upon which they rely are under increasing pressure due to a combination of biotic and abiotic anthropogenic stressors. Unfortunately, conventional survey methods used to monitor ecosystems are often challenging to conduct on large scales. Pan traps are a commonly used pollinator survey method and environmental DNA (eDNA) metabarcoding of pan trap water may offer a high-throughput alternative to aid in the detection of both arthropods and the plant resources they rely on. Here, we examined if eDNA metabarcoding can be used to identify arthropods and plant species from pan trap water, and …

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Future-Proofing The Past: Artificial Intelligence In The Restoration Of Andalusian Architectural Heritage: A Case Study Of The Alhambra Palace, Granada, Spain, Kholoud Bader Hasan Ghaith Mar 2024

Future-Proofing The Past: Artificial Intelligence In The Restoration Of Andalusian Architectural Heritage: A Case Study Of The Alhambra Palace, Granada, Spain, Kholoud Bader Hasan Ghaith

Theses

This thesis explains the contribution of artificial intelligence in heritage restoration as an icon of Andalusian architecture by using the Alhambra as an example. The task of sustaining heritage is increasing dramatically due to the accumulation of heritage assets and the need for modern and innovative operations to cope with preservation tasks. Therefore, this thesis reviews the role of artificial intelligence in improving the restoration operation to improve accuracy and efficiency. I applied the case study as a scientific methodology to explain this work to overcome scientific and subjective obstacles, such as scarce data and software integration while explaining the …

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Synthesis And Crystal Structures Of Bis[1-Oxopyridin-2-Olato(1−)]Bis(Pentafluorophenyl)Silicon(Iv)–Tetrahydrofuran–Pentane (2/1/1), Bis[1-Oxopyridin-2-Olato(1−)]Bis(P-Tolyl)Silicon(Iv), And Dimesitylbis[1-Oxopyridin-2-Olato(1−)]Silicon(Iv), Bradley M. Kraft, William W. Brennessel, Jordan W. Andrews, Michael T. Viggiani, Nathan F. Kittrell, Matthew T. Heckman Mar 2024

Synthesis And Crystal Structures Of Bis[1-Oxopyridin-2-Olato(1−)]Bis(Pentafluorophenyl)Silicon(Iv)–Tetrahydrofuran–Pentane (2/1/1), Bis[1-Oxopyridin-2-Olato(1−)]Bis(P-Tolyl)Silicon(Iv), And Dimesitylbis[1-Oxopyridin-2-Olato(1−)]Silicon(Iv), Bradley M. Kraft, William W. Brennessel, Jordan W. Andrews, Michael T. Viggiani, Nathan F. Kittrell, Matthew T. Heckman

Chemistry Faculty/Staff Publications

The neutral organosilicon(IV) complex, (C6F5)2Si(OPO)2 (OPO = 1-oxopyridin-2-one, C5H4NO2), was synthesized from (C6F5)2Si(OCH3)2 and 2 equiv. of 1-hy­droxy­pyridin-2-one in tetra­hydro­furan (THF). Single crystals grown from the diffusion of n-pentane into a THF solution were identified as a THF hemisolvate and an n-pentane hemisolvate, (C6F5)2Si(OPO)2·0.5THF·0.5C5H12 (1). p-Tol­yl2Si(OPO)2 (2) and mesit­yl2Si(OPO)2 (3) crystallized directly from reaction mixtures of 2 equiv. of Me3Si(OPO) with p-tol­yl2SiCl2 and mesit­yl2SiCl2, respectively, in aceto­nitrile. The oxygen-bonded carbon and nitro­gen atoms of the OPO ligands in 1, 2, and 3 were modeled as disordered indicating co-crystallization …

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Light Curve And Hardness Tests For Millilensing In Grb 081122a, Grb 081126a, Grb 110517b, And Grb 210812a, Oindabi Mukherjee, Robert J. Nemiroff Mar 2024

Light Curve And Hardness Tests For Millilensing In Grb 081122a, Grb 081126a, Grb 110517b, And Grb 210812a, Oindabi Mukherjee, Robert J. Nemiroff

Michigan Tech Publications, Part 2

Analyses are given on four recent gravitational millilensing claims on gamma-ray bursts (GRBs): GRB 081122A, GRB 081126A, GRB 110517B, and GRB 210812A. Two tests, a light curve similarity test and a hardness similarity test, compare different temporal sections of a single GRB to see if they are statistically similar. The hardness similarity test shows that the ratio between the second and the first emission episodes in each energy channel differed from the same ratio averaged over all energy channels at above 90 per cent confidence level in GRB 081122A. Additionally, the light curve similarity test applied to GRB 081122A, GRB …

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Hearing Iterative And Recursive Behavior: Sonification Improves Student Understanding, Joel C. Adams, Hayworth Anderson Mar 2024

Hearing Iterative And Recursive Behavior: Sonification Improves Student Understanding, Joel C. Adams, Hayworth Anderson

University Faculty Publications and Creative Works

Abstract topics such as recursion are challenging for many computer science students to understand. In this experience report, we explore function sonification-the addition of sound to a function to communicate information about the function's behavior in real-time as it runs-as a pedagogical approach for improving students' understanding of recursion. We present several example iterative and recursive function sonifications, plus spectrograms that illustrate their different sonic behaviors. We also present experimental evidence that using these sonifications significantly improved the understanding of recursion for students who used them, compared to students who used silent (i.e., traditional) versions of the same functions. Based …

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Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton Mar 2024

Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton

Physics and Astronomy Faculty Publications and Presentations

No abstract provided.

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Investigating Communication Of Findings In Environmental Impact Assessment And Developing A Research Agenda For Improvement, Alan Bond, Francois Retief, Angus Morrison-Saunders, Jenny Pope, Reece C. Alberts, Claudine Roos, Dirk Cilliers Mar 2024

Investigating Communication Of Findings In Environmental Impact Assessment And Developing A Research Agenda For Improvement, Alan Bond, Francois Retief, Angus Morrison-Saunders, Jenny Pope, Reece C. Alberts, Claudine Roos, Dirk Cilliers

Research outputs 2022 to 2026

Environmental Impact Assessment (EIA) aims to embed consideration of the significance of predicted environmental consequences (the findings) of proposed developments into approval decision making. Achieving this aim relies on adequate communication of the findings of the EIA to the stakeholders, especially the decision makers responsible for the approval decision. However, the naïve assumption that this communication of findings can be effectively achieved through the publication of a written report pervades legislation worldwide, despite decades of evidence to the contrary. As a first step towards improving such communication, this research identifies the contingent conditions associated with effectively transferring EIA findings from …

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A 2,000-Year Record Of Eelgrass (Zostera Marina L.) Colonization Shows Substantial Gains In Blue Carbon Storage And Nutrient Retention, Martin Dahl, Martin Gullström, Irene Bernabeu, Oscar Serrano, Carmen Leiva-Dueñas, Hans W. Linderholm, Maria E. Asplund, Mats Björk, Tinghai Ou, J. Robin Svensson, Elinor Andrén, Thomas Andrén, Sanne Bergman, Sara Braun, Anneli Eklöf, Zilvinas Ežerinskis, Andrius Garbaras, Petter Hällberg, Elin Löfgren, Malin E. Kylander, Pere Masqué, Justina Šapolaitė, Rienk Smittenberg, Miguel A. Mateo Mar 2024

A 2,000-Year Record Of Eelgrass (Zostera Marina L.) Colonization Shows Substantial Gains In Blue Carbon Storage And Nutrient Retention, Martin Dahl, Martin Gullström, Irene Bernabeu, Oscar Serrano, Carmen Leiva-Dueñas, Hans W. Linderholm, Maria E. Asplund, Mats Björk, Tinghai Ou, J. Robin Svensson, Elinor Andrén, Thomas Andrén, Sanne Bergman, Sara Braun, Anneli Eklöf, Zilvinas Ežerinskis, Andrius Garbaras, Petter Hällberg, Elin Löfgren, Malin E. Kylander, Pere Masqué, Justina Šapolaitė, Rienk Smittenberg, Miguel A. Mateo

Research outputs 2022 to 2026

Assessing historical environmental conditions linked to habitat colonization is important for understanding long-term resilience and improving conservation and restoration efforts. Such information is lacking for the seagrass Zostera marina, an important foundation species across cold-temperate coastal areas of the Northern Hemisphere. Here, we reconstructed environmental conditions during the last 14,000 years from sediment cores in two eelgrass (Z. marina) meadows along the Swedish west coast, with the main aims to identify the time frame of seagrass colonization and describe subsequent biogeochemical changes following establishment. Based on vegetation proxies (lipid biomarkers), eelgrass colonization occurred about 2,000 years ago after geomorphological changes …

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Introducing Pour Points: Characteristics And Hydrological Significance Of A Rainfall-Concentrating Mechanism In A Water-Limited Woodland Ecosystem, Ashvath S. Kunadi, Tim Lardner, Richard P. Silberstein, Matthias Leopold, Nik Callow, Erik Veneklaas, Aryan Puri, Eleanor Sydney, Sally E. Thompson Mar 2024

Introducing Pour Points: Characteristics And Hydrological Significance Of A Rainfall-Concentrating Mechanism In A Water-Limited Woodland Ecosystem, Ashvath S. Kunadi, Tim Lardner, Richard P. Silberstein, Matthias Leopold, Nik Callow, Erik Veneklaas, Aryan Puri, Eleanor Sydney, Sally E. Thompson

Research outputs 2022 to 2026

The interception of rainfall by plant canopies alters the depth and spatial distribution of water arriving at the soil surface, and thus the location, volume, and depth of infiltration. Mechanisms like stemflow are known to concentrate rainfall and route it deep into the soil, yet other mechanisms of flow concentration are poorly understood. This study characterizes pour points, formed by the detachment of water flowing under a branch, using a combination of field observations in Western Australian banksia woodlands and rainfall simulation experiments on Banksia menziesii branches. We aim to establish the hydrological significance of pour points in a water-limited …

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Voice Synthesis Improvement By Machine Learning Of Natural Prosody, Joseph Kane, Michael N. Johnstone, Patryk Szewczyk Mar 2024

Voice Synthesis Improvement By Machine Learning Of Natural Prosody, Joseph Kane, Michael N. Johnstone, Patryk Szewczyk

Research outputs 2022 to 2026

Since the advent of modern computing, researchers have striven to make the human–computer interface (HCI) as seamless as possible. Progress has been made on various fronts, e.g., the desktop metaphor (interface design) and natural language processing (input). One area receiving attention recently is voice activation and its corollary, computer-generated speech. Despite decades of research and development, most computer-generated voices remain easily identifiable as non-human. Prosody in speech has two primary components—intonation and rhythm—both often lacking in computer-generated voices. This research aims to enhance computer-generated text-to-speech algorithms by incorporating melodic and prosodic elements of human speech. This study explores a novel …

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Antioxidant Properties Of Kombucha Beverage Infused With Ganoderma Lucidum And Green Tea From Camellia Sinensis (L.) Kuntze With Several Fermentation Times, Rizki Rabeca Elfirta, Pamungkas Rizki Ferdian, Iwan Saskiawan, Tri Hadi Handayani, Kayla Faza Gustafri Mandalika, Rini Riffiani, Kasirah Kasirah, Ukhradiya Magharaniq Safira Purwanto Feb 2024

Antioxidant Properties Of Kombucha Beverage Infused With Ganoderma Lucidum And Green Tea From Camellia Sinensis (L.) Kuntze With Several Fermentation Times, Rizki Rabeca Elfirta, Pamungkas Rizki Ferdian, Iwan Saskiawan, Tri Hadi Handayani, Kayla Faza Gustafri Mandalika, Rini Riffiani, Kasirah Kasirah, Ukhradiya Magharaniq Safira Purwanto

Karbala International Journal of Modern Science

Kombucha is a functional beverage produced through the fermentation of infused tea or Camelia sinensis (L.) Kuntze (CS) by a symbiotic culture of bacteria and yeast. Apparently, the substrate of kombucha can be substituted to enhance its functional properties. Ganoderma lucidum (GL) is a potential substrate reported to have health benefits. This study aims to evaluate antioxidant properties by comparing different formulations and fermentation times. The formulations prepared in the present study varied in the compositions of GL and CS substrates, namely F1 (100% GL), F2 (75% GL: 25% CS), F3 (50% GL: 50% CS), F4 (25% GL: 75% CS), …

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Relocating Lubra Village And Visualizing Himalayan Flood Damages With Remote Sensing, Ronan Wallace, Yungdrung Tsewang Gurung, Ryan Kastner Feb 2024

Relocating Lubra Village And Visualizing Himalayan Flood Damages With Remote Sensing, Ronan Wallace, Yungdrung Tsewang Gurung, Ryan Kastner

Journal of Critical Global Issues

As weather patterns change worldwide, isolated communities impacted by climate change go unnoticed and we need community-driven solutions. In Himalayan Mustang, Nepal, indigenous Lubra Village faces threats of increasing flash flooding. After every flood, residual muddy sediment hardens across the riverbed like concrete, causing the riverbed elevation to rise. As elevation increases, sediment encroaches on Lubra’s agricultural fields and homes, magnifying flood vulnerability. In the last monsoon season alone, the Lubra community witnessed floods swallowing several agricultural fields and damaging two homes. One solution considers relocating the village to a new location entirely. However, relocation poses a challenging task, as …

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Environmental Analysis Of Codfish Production And Consumption In Portugal, Ayla Frost, Joana Almeida, Joana Dionisio, Radu Godina, Cátia Magro Feb 2024

Environmental Analysis Of Codfish Production And Consumption In Portugal, Ayla Frost, Joana Almeida, Joana Dionisio, Radu Godina, Cátia Magro

Journal of Critical Global Issues

Codfish, a typical dish consumed frequently in Portugal, is fished in the cold Northern Atlantic waters far from the Portuguese coast. Thus, regional tensions and the environmental impacts of Portuguese codfish importation and production are significant current issues. The present study uses a life cycle assessment methodology to evaluate the array of environmental impacts of the production of 1 kg of codfish, following a cradle to gate approach. The life cycle inventory was grouped into catch and preprocessing, transit, and curing stages. The data collection of products and processes in each stage was based on scientific peer reviewed documents, technical …

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Germplasm Enhancement Of Annual Forage Legumes Suitable For Use In Cold Highland Environments, H K. Firincioglu, N Karagullu, S Unal, A M. Abd-El Moneim Feb 2024

Germplasm Enhancement Of Annual Forage Legumes Suitable For Use In Cold Highland Environments, H K. Firincioglu, N Karagullu, S Unal, A M. Abd-El Moneim

IGC Proceedings (1993-2023)

The Central Highlands (CH) of Turkey are characterized by cold winters and dry summers. Under these extreme air temperatures, forage crops are still underexploited as a part of crop rotations. Half of the total vetch hectarage in Turkey is in the CH, and farmers still use the local cultivars that have good adaptability but low yield potential. Therefore, with the aim of identifying and improving the annual forage legume species for the cold and dry environment of the CH, research work was carried out during the 1993/94 and 1994/ 95 crop seasons. Initial results showed that Hungarian vetch (Vicia …

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Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates Feb 2024

Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates

IGC Proceedings (1993-2023)

The objective of these studies was to determine, in the context of a forage breeding program, the effect of cattle grazing on survival of alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), and tall fescue (Festuca arundinacea Schreb.). Different cultivars of each species were compared in grazed and ungrazed areas. Results consistently demonstrated that grazing reduced plant stands when compared to ungrazed conditions for each species tested. In alfalfa, however, cultivars developed for grazing tolerance showed much better grazing survival. Infection with the fungal endophyte, Acremonium coenophialum Morgan-Jones & Gams, likewise substantially increased grazing survival in …

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Study Of Genotype X Environment Interaction In Alfalfa Forage Yield, S N. Acharya, G C. Kozub, H Najda, A Aasen Feb 2024

Study Of Genotype X Environment Interaction In Alfalfa Forage Yield, S N. Acharya, G C. Kozub, H Najda, A Aasen

IGC Proceedings (1993-2023)

The response of alfalfa (Medicago sativa L.) forage yield to eight Alberta test sites was studied for the 1990 and 1991 production years. Cluster analysis was used to group locations and cultivars. Analyses of variances indicated genotype x environment (location) interaction for the first cut yield, the total yield and the difference between first and second cut yields. The Brooks, Bow Island (irrigation), Bow Island (dryland) and Provost locations always clustered together indicating that three of these four test sites may be eliminated without sacrificing reliability.

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Selection For Self-Fertility And Self-Fertility In Alfalfa As A Tool For Breeding Strategy Assessment, D Rosellini, F Veronesi, F Lorenzetti Feb 2024

Selection For Self-Fertility And Self-Fertility In Alfalfa As A Tool For Breeding Strategy Assessment, D Rosellini, F Veronesi, F Lorenzetti

IGC Proceedings (1993-2023)

Cultivar development in alfalfa relies on heterosis, that has been mainly exploited by intercrossing selected clones from diverse gemplasm sources; an alternative way was proposed, based on developing double cross cultivars obtained by crossing clones selected for self-sterility, propagated by somatic seed. A different breeding strategy was recently emphasized based on population improvement through inbreeding and recurrent selection; in this case, self-sterility would be selected against. If self-sterility is determined by genetic load, the second strategy should be preferred, and selecting for self-fertility may bring about positive correlated responses for forage yield. Divergent selection for self-fertility was applied in a …

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Morphological And Rapd Variations And Regenerants Derived From Cell Suspension Culture Of Pangolagrass, C S. Chen, S M. Wang, Y K. Cheng Feb 2024

Morphological And Rapd Variations And Regenerants Derived From Cell Suspension Culture Of Pangolagrass, C S. Chen, S M. Wang, Y K. Cheng

IGC Proceedings (1993-2023)

Pangolagrass cv. A254, a sterile strain, is one of Taiwan's major forage sources but recently has faced serious disease problems. Tissue culture was expected to generate variations in the breeding program of pangolagrass. The purpose of this study is to examine the somaclonal variation of regenerated plants by means of phenotypic characters survey and RAPD analysis. After long-term suspension culture and EMS mutagenesis, many regenerated plants with morphological variations have been found. Among the regenerants, 10 clones with obviously different characteristics were selected for further studies. Nine of them showed significant differences in morphological trains as compared to A254. By …

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Phylogenetics Of Apomictic Common Dallisgrass (Paspalum Dilatatum), B L. Burson, M A. Hussey Feb 2024

Phylogenetics Of Apomictic Common Dallisgrass (Paspalum Dilatatum), B L. Burson, M A. Hussey

IGC Proceedings (1993-2023)

Common dallisgrass, Paspalum dilatatum Poir., an important warm season forage grass, is an obligate apomict with 50 chromosomes which associate as 20 bivalents and 10 univalents during meiosis. Because efforts to improve the grass have not been successful, a phylogenetic investigation was initiated to identify the progenitors of common dallisgrass in an effort to circumvent the apomictic barrier to improvement. The genomic composition has been determined for four dallisgrass biotypes: yellow-anthered (2n=4x=40) IIJJ; common (2n=5x=50) IIJJX; Uruguayan (2n=6x=60) IIJJXX; and Uruguaiana (2n=6x=60) IIJJXX. While the source of the X genome is unknown, the genes controlling apomixis are on at least …

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Increased Longevity Of Red Clover Through Selection For Persistence And Disease Resistance, R R. Smith Feb 2024

Increased Longevity Of Red Clover Through Selection For Persistence And Disease Resistance, R R. Smith

IGC Proceedings (1993-2023)

Red clover (Trifolium pratense L.), an excellent perennial forage legume, has been considered for many years to be a short-lived, two to three years, forage. Selection for resistance to foliar and root rot diseases and for longevity of stand over the past four decades has improved the persistence of the currently available cultivars. The present studies were conducted to evaluate the progress from selection for longevity and disease resistance. Selection for stand longevity and improved disease resistance has reliably extended the production of red clover into the third and fourth year. Selection for healthy plants in 3- or …

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Backcrosses Of Diploid Lolium-Festuca Hybrids To Festuca, W Nitzche Feb 2024

Backcrosses Of Diploid Lolium-Festuca Hybrids To Festuca, W Nitzche

IGC Proceedings (1993-2023)

Fertile diploid hybrids of Lolium x Festuca -backcrosses were produced by colchicine-treatment without chromosome doubling. The hybrids have new combinations of their characters, not known in the natural species.

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Selection For Herbage Yield And Flowering In Ladino White Clover, J A. Garcia Feb 2024

Selection For Herbage Yield And Flowering In Ladino White Clover, J A. Garcia

IGC Proceedings (1993-2023)

A geno-phenotypic recurrent selection program is being carried out on ladino white clover (Trifolium repens L.) aiming to combine good DM and seed yields. Selection criteria includes plant density, vigor, winter growth, flowering and diseases resistance. The performance of selections in terms of DM yields and seed production was evaluated in separate trials. Two cycles of selection increased flowering by 36% and seed yield by 59%. Preliminary data on herbage yields shows a very good performance of the selected material and suggests the feasibility of combining high DM and seed yields.

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Selection For Field Survival Increases Freezing Tolerance In Festulolium, M D. Casler, P G. Pitts, P C. Bilkey, C A. Rose-Fricker Feb 2024

Selection For Field Survival Increases Freezing Tolerance In Festulolium, M D. Casler, P G. Pitts, P C. Bilkey, C A. Rose-Fricker

IGC Proceedings (1993-2023)

Festulolium (Festulolium braunii K.A.) is marginally adapted to the north central and northeastern USA and southern Canada. The purpose of this study was to evaluate four festulolium populations selected for field survival under harsh winter conditions for their freezing tolerance in controlled environments. Progenies of all four populations showed some improvement in freezing tolerance compared to their parents. Improvements were dependent on the temperature at which measurements were made and varied among germplasms. Improvements were manifested in both decreased plant mortality and decreased injury to surviving plants. Genetic variation for freezing tolerance appears to be a viable mechanism …

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Fitness Of Apomictic And Sexual Buffelgrass Germplasm, M A. Hussey, Yue-Wen Wang, B L. Burson Feb 2024

Fitness Of Apomictic And Sexual Buffelgrass Germplasm, M A. Hussey, Yue-Wen Wang, B L. Burson

IGC Proceedings (1993-2023)

Breeding apomictic grasses is based on either the direct selection of apomictic landraces or the hybridization of sexual and apomictic types and selection of apomictic F1 hybrids. Little is known about the potential of sexual hybrids as cultivars in apomictic species. To determine if method of reproduction (MOR) was related to plant vigor, parental, S1, and F1 hybrids of buffelgrass differing in method of reproduction (apomictic or sexual) were established in a common garden in 1994 and 1995. In both years severe inbreeding depression was observed in the S1 progeny as they were shorter, produced less biomass, and had low …

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Selection For Nitrogen Use Efficiency In Perennial Ryegrass Using Hydroponics, E N. Van Loo, A.J. P. Van Wijk, O Dolstra, H.J. P. Marvin, C.H. A. Snijders Feb 2024

Selection For Nitrogen Use Efficiency In Perennial Ryegrass Using Hydroponics, E N. Van Loo, A.J. P. Van Wijk, O Dolstra, H.J. P. Marvin, C.H. A. Snijders

IGC Proceedings (1993-2023)

A selection method was tested for improving nitrogen use efficiency of perennial ryegrass (Lolium perenne L.) using a hydroponics system that controls the plant nitrogen concentration. Divergent selection for plant production, leaf area increase and dry matter distribution in six segregating populations under limiting nitrogen supply resulted in differences between offspring of upward and downward selections larger than 20 % in most characteristics. Moderately high realized heritabilities were found for some characteristics (up to 0.88). It is concluded that early selection for nitrogen use efficiency is feasible using this hydroponics system.

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Development Of A Multicross Cultivars Of Stylosanthes Spp., B Grof, C D. Fernandes, C B. Almeida, A V. Dos Santos Feb 2024

Development Of A Multicross Cultivars Of Stylosanthes Spp., B Grof, C D. Fernandes, C B. Almeida, A V. Dos Santos

IGC Proceedings (1993-2023)

A synthetic population, referred to as multicross, has been developed from an interspecific mixture of Stylosanthes capitata and S.macrocephala germplasm. This basic population evolved in a farming situation subject to uncontrolled, continuous, heavy grazing. Natural selection and systematically programmed intercrossing among anthracnose-resistant Venezuelan and Brazilian genotypes of S.capitata have played major roles in the subsequent development of this heterogeneous population. Eight anthracnose-resistant Venezuelan and two Brazilian accessions of S.capitata were introgressed into the basic population. Genetic diversity was further increased by adding seed of four selected accessions of S. macrocephala to the synthetic which had already included …

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Selection Of Stylosanthes Guianensis For The Cerrados Of Brazil, B Grof, C D. Fernandes, A V. Dos Santos, C B. Almeida Feb 2024

Selection Of Stylosanthes Guianensis For The Cerrados Of Brazil, B Grof, C D. Fernandes, A V. Dos Santos, C B. Almeida

IGC Proceedings (1993-2023)

Progenies of intervarietal hybrid stylos (Stylosanthes guianensis var.vulgaris x S.guianensis var.pauciflora) with mid-season maturity date (early-and mid-June), high dry matter and seed yields have been identified at the National Beef Cattle Research Center (CNPGC), Campo Grande, MS, Brazil. Dry matter yields of the best selections were comparable to those of the late-flowering control, cv. Mineirão. Several mid-season hybrids produced 150 to 200 kg/ha of seed-inpod and a single plant selection yielded in excess of 300 kg/ha. The high degree of resistance to anthracnose observed in the advanced generations is attributed to the immense genetic diversity of these …

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Development Of Red Clover With High Levels Of Resistance To Root-Knot Nematodes, K H. Quesenberry, R A. Dunn, D E. Moon Feb 2024

Development Of Red Clover With High Levels Of Resistance To Root-Knot Nematodes, K H. Quesenberry, R A. Dunn, D E. Moon

IGC Proceedings (1993-2023)

Red clover (Trifolium pratense L.), is grown in many areas of the world, but production in subtropical regions may be limited by susceptibility to root-knot nematodes (Meloidogyne spp.) (RKN). Selection for early vigor in RKN infested soils resulted in moderate RKN tolerance in ‘Cherokee’. However, improved RKN resistance in red clover was needed. Seven additional cycles of greenhouse selection using Cherokee as a base population developed a population (FLMR7) with high RKN resistance. When FLMR7 was infested with M. arenaria, M. hapla, M. incognita, or M. javanica, numbers of galls and egg masses …

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Evaluating White Clover For Resistance To Cylindrocladium Root Rot, D S. Wofford, A Amaya Feb 2024

Evaluating White Clover For Resistance To Cylindrocladium Root Rot, D S. Wofford, A Amaya

IGC Proceedings (1993-2023)

A rapid screening technique was developed for use in evaluating white clover (Trifolium repens L.) for resistance to Cylindrocladium root rot incited by Cylindrocladium crotalariae. Culture plates of the fungus were evaluated for number of infective propagules after four weeks of growth on potato dextrose agar, and no differences were detected among plates. Seedlings of ‘Osceola’ white clover were exposed in the greenhouse to four levels of inoculum over a six-week period, with resistance based on percent survival of uninoculated controls. It was shown that suspending 1 culture plate in 100ml of water and rating plants four weeks …

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Characterization Of Chilling Sensitivity Of Tropical And Temperate Grasses, M Ebina, K Okumura, H Matsu-Ura, Y Tsurumi Feb 2024

Characterization Of Chilling Sensitivity Of Tropical And Temperate Grasses, M Ebina, K Okumura, H Matsu-Ura, Y Tsurumi

IGC Proceedings (1993-2023)

C16-C18 fatty acid composition of some lipids in several species of temperate and tropical grasses were measured. The fatty acid composition of phosphatidylglycerol (PG) and sulfoquinovosyl diglyceride (SQDG) indicated significant differences between temperate and tropical grasses. Especially the differences of the fatty acid composition of PG were remarkable. The unsaturated fatty acid content of PG in tropical grasses was lower than the contents in temperate grasses. These differences constantly appeared through the year. These differences were caused by the low content of polyunsaturated fatty acids, or the low contents of C18 fatty acids.

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