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Herbage Seed Production Possibilities In Finland, O. Niemeläinen, M. Kinnari Sep 2021

Herbage Seed Production Possibilities In Finland, O. Niemeläinen, M. Kinnari

IGC Proceedings (1977-2023)

In the seed production variety experiments in Finland from 1977 to 1992 the mean seed yield of timothy (Phleum pratense) cultivar Alma was 717 kg ha-1, of meadow fescue (Festuca pratensis) cv. Boris 622 kg ha-1, of tall fescue (Festuca arundinacea) cv. Retu 350 kg ha-1, of perennial ryegrass (Lolium perenne) cv. Riikka, of cocksfoot (Dactylis glomerata) cv. Haka 295 kg ha-1, and red clover (Trifolium pratense) cv. Hankkijan Venla 403 kg ha-1. From 1988 to 1998 annual …


Forage News [2021-09], Department Of Plant And Soil Sciences, University Of Kentucky Sep 2021

Forage News [2021-09], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

No abstract provided.


In Situ Imaging Of Bacterial Outer Membrane Projections And Associated Protein Complexes Using Electron Cryo-Tomography, Mohammed Kaplan, Georges Chreifi, Lauren Ann Metskas, Janine Liedtke, Cecily R. Wood, Catherine M. Oikonomou, William J. Nicolas, Poorna Subramanian, Lori A. Zacharoff, Yuhang Wang, Yi-Wei Chang, Morgan Beeby, Megan J. Dobro, Yongtao Zhu, Mark J. Mcbride, Ariane Briegel, Carrie L. Shaffer, Grant J. Jensen Sep 2021

In Situ Imaging Of Bacterial Outer Membrane Projections And Associated Protein Complexes Using Electron Cryo-Tomography, Mohammed Kaplan, Georges Chreifi, Lauren Ann Metskas, Janine Liedtke, Cecily R. Wood, Catherine M. Oikonomou, William J. Nicolas, Poorna Subramanian, Lori A. Zacharoff, Yuhang Wang, Yi-Wei Chang, Morgan Beeby, Megan J. Dobro, Yongtao Zhu, Mark J. Mcbride, Ariane Briegel, Carrie L. Shaffer, Grant J. Jensen

Veterinary Science Faculty Publications

The ability to produce outer membrane projections in the form of tubular membrane extensions (MEs) and membrane vesicles (MVs) is a widespread phenomenon among diderm bacteria. Despite this, our knowledge of the ultrastructure of these extensions and their associated protein complexes remains limited. Here, we surveyed the ultrastructure and formation of MEs and MVs, and their associated protein complexes, in tens of thousands of electron cryo-tomograms of ~90 bacterial species that we have collected for various projects over the past 15 years (Jensen lab database), in addition to data generated in the Briegel lab. We identified outer MEs and MVs …


Endophytes Of Brazilian Medicinal Plants With Activity Against Phytopathogens, Jucélia Iantas, Daiani Cristina Savi, Renata Da Silva Schibelbein, Sandriele Aparecida Noriler, Beatriz Marques Assad, Guilherme Dilarri, Henrique Ferreira, Jürgen Rohr, Jon S. Thorson, Khaled A. Shaaban, Chirlei Glienke Sep 2021

Endophytes Of Brazilian Medicinal Plants With Activity Against Phytopathogens, Jucélia Iantas, Daiani Cristina Savi, Renata Da Silva Schibelbein, Sandriele Aparecida Noriler, Beatriz Marques Assad, Guilherme Dilarri, Henrique Ferreira, Jürgen Rohr, Jon S. Thorson, Khaled A. Shaaban, Chirlei Glienke

Pharmaceutical Sciences Faculty Publications

Plant diseases caused by phytopathogens are responsible for significant crop losses worldwide. Resistance induction and biological control have been exploited in agriculture due to their enormous potential. In this study, we investigated the antimicrobial potential of endophytic fungi of leaves and petioles of medicinal plants Vochysia divergens and Stryphnodendron adstringens located in two regions of high diversity in Brazil, Pantanal, and Cerrado, respectively. We recovered 1,304 fungal isolates and based on the characteristics of the culture, were assigned to 159 phenotypes. One isolate was selected as representative of each phenotype and studied for antimicrobial activity against phytopathogens. Isolates with better …


Power Factor And Reactive Power In Us Residences – Survey And Energyplus Modeling, Hope C. Anderson, Abdullah Al Hadi, Evan S. Jones, Dan M. Ionel Sep 2021

Power Factor And Reactive Power In Us Residences – Survey And Energyplus Modeling, Hope C. Anderson, Abdullah Al Hadi, Evan S. Jones, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Electric power systems are experiencing a growing number of electronic loads in the residential sector as modern appliance technology progresses, and it has become increasingly more important to consider the total power factor (PF) of residential communities. This paper provides a survey based on literature and publicly available information of typical appliance PF values and effects at the residential level as well as a discussion on appliance energy use and corresponding operation schedules. A procedure for the calculation of equivalent PF is proposed and exemplified with minutely experimental data at 15-minute and hourly time intervals, which correspond to smart metering …


2021 Safety Belt Usage Survey In Kentucky, Erin Lammers-Staats, Kenneth Agent, Eric Green Sep 2021

2021 Safety Belt Usage Survey In Kentucky, Erin Lammers-Staats, Kenneth Agent, Eric Green

Kentucky Transportation Center Research Report

The objective of the survey summarized in this report was to establish a statewide safety belt usage rate in Kentucky for 2021. This rate can be compared to those determined from previous surveys. The 2021 statewide survey documents the continued effect associated with law enforcement, related education, and general public attitude.


Improving Overweight And Over-Dimensional Logistics And Truck Routing, Jerry Kissick, Jerry Pigman, Jennifer Walton Sep 2021

Improving Overweight And Over-Dimensional Logistics And Truck Routing, Jerry Kissick, Jerry Pigman, Jennifer Walton

Kentucky Transportation Center Research Report

In 2012, the Kentucky Transportation Cabinet’s (KYTC) Division of Motor Carriers (DMC) issued 98,196 overweight or over-dimensional (OW/OD) permits. To determine whether a route can accommodate an OW/OD vehicle, analysts must have current and accurate data on construction schedules, road conditions, and detour routes, among other factors. This study documents processes used by DMC for permitting and routing OW/OD vehicles. It includes detailed flowcharts that capture each aspect analysts follow during the decision-making process. As part of this project, state transportation agency representatives from states bordering Kentucky (Illinois, Indiana, Ohio, West Virginia, Virginia, Tennessee, and Missouri) were interviewed to identify …


Kentucky Traffic Collision Facts 2020, Eric Green, Paul Ross, Christopher Blackden, Michael Fields, Kenneth Agent Sep 2021

Kentucky Traffic Collision Facts 2020, Eric Green, Paul Ross, Christopher Blackden, Michael Fields, Kenneth Agent

Kentucky Transportation Center Research Report

KENTUCKY’S TRAFFIC COLLISION FACTS report is based on collision reports submitted to the Kentucky State Police Records Branch. As required by Kentucky Revised Statutes 189.635:

“Every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.”

The stated purpose of this requirement is to utilize data on traffic collisions for such purposes as will improve the traffic safety program in the Commonwealth.


Analysis Of Traffic Crash Data In Kentucky 2016-2020, Eric Green, Paul Ross, Christopher Blackden, Michael Fields, William Staats Sep 2021

Analysis Of Traffic Crash Data In Kentucky 2016-2020, Eric Green, Paul Ross, Christopher Blackden, Michael Fields, William Staats

Kentucky Transportation Center Research Report

This report documents analysis of traffic crash data in Kentucky. A primary objective of this study was to determine average crash statistics for Kentucky highways. Where used, rates were calculated for various highway types and for counties and cities. Difference criteria were used for exposure.

Average and critical numbers, SPFs, and crash rates were calculated for various highway types in rural and urban areas. These metrics rely on crashes identified on highways where Annual Average Daily Traffic (AADT) volumes were available. Data in this report may be used to help identify problem areas.

The other primary objective of this study …


Crash Data Analysis Tool 2.0 Research Report And User Guide, Eric Green, Paul Ross Sep 2021

Crash Data Analysis Tool 2.0 Research Report And User Guide, Eric Green, Paul Ross

Kentucky Transportation Center Research Report

No abstract provided.


In-Cab Alert System For Commercial Motor Vehicle Drivers, Brian Howell, Jennifer Walton, Jeeyen Koo Sep 2021

In-Cab Alert System For Commercial Motor Vehicle Drivers, Brian Howell, Jennifer Walton, Jeeyen Koo

Kentucky Transportation Center Research Report

In-cab telematic devices use an increasingly robust data platform and can be used to share safety alerts with other commercial vehicle drivers (CMV) drivers. Real-time alert data can come from state transportation agencies as well as from private companies. To address common quality and coordination issues among differing data sources, the Kentucky Transportation Center (KTC) partnered with the Kentucky Transportation Cabinet (KYTC) and a private vendor, PrePass, to share its App used to send information to CMV drivers. The project demonstrated a proof of concept for the delivery of timely in-cab alerts to warn CMV drivers of approaching roadway hazards. …


Application Of Artificial Neural Networks To Power System State Estimation, James P. Carmichael, Yuan Liao Aug 2021

Application Of Artificial Neural Networks To Power System State Estimation, James P. Carmichael, Yuan Liao

Electrical and Computer Engineering Presentations

State estimation function is essential for effective and timely execution of power system automation and control systems, especially in modern active distribution systems where more intermittent renewable energy systems are integrated into the grid. Distribution system state estimation faces a lot of challenges including lack of monitoring devices and possible incorrect topology information. Developing efficient state estimation for distribution systems is thus of great interest. This paper presents results on utilizing artificial neural networks for this purpose.

Artificial neural networks have been used in power distribution system state estimation. However, there is a lack of systematic analysis and study of …


Role Of Protective Relaying In The Smart Grid, J. Anderson, Alex Apostolov, R. Fowler, J. Gers, R. Kazimier, S. Klecker, Yuan Liao, M. Majidi, P. Myrda, T. Raffield Aug 2021

Role Of Protective Relaying In The Smart Grid, J. Anderson, Alex Apostolov, R. Fowler, J. Gers, R. Kazimier, S. Klecker, Yuan Liao, M. Majidi, P. Myrda, T. Raffield

Electrical and Computer Engineering Presentations

This paper discusses the role of protective relaying in a Smart Grid. It outlines the definition, attributes, and benefits of a Smart Grid. The role that protective relays can play in implementing Smart Grid functionality and the impact that a Smart Grid design may have on modern protective relays is discussed. Specific examples of Smart Grid applications that may be implemented using modern protective relays and other intelligent electronic devices are provided.


Geomagnetic Disturbances (Gmd) Impacts On Protection Systems, Qun Qiu, V. Madani, Tapan Manna, T. Raffield, S. Klecker, Yuan Liao, S. Meliopoulos, D. Fontana Aug 2021

Geomagnetic Disturbances (Gmd) Impacts On Protection Systems, Qun Qiu, V. Madani, Tapan Manna, T. Raffield, S. Klecker, Yuan Liao, S. Meliopoulos, D. Fontana

Electrical and Computer Engineering Presentations

This paper provides background and historical events of Geomagnetic Disturbances (GMD), and reviews GMD impacts on power systems equipment, and associated protection and control systems, mitigating measures, and Geomagnetic Induced Current (GIC) monitoring methods. This paper is a summary of the IEEE PES-TR72 report, titled, GMD Impacts on Protection Systems, prepared by the K17 Working Group of the IEEE Power System Relaying and Control committee.


Bee Assemblages Data [2021], Daniel A. Potter, Bernadette M. Mach Aug 2021

Bee Assemblages Data [2021], Daniel A. Potter, Bernadette M. Mach

Entomology Research Data

Plant characteristics, sample sites, and non-native bee assemblages for a bee survey conducted in 2014-2017 by Bernadette Mach in the Daniel A. Potter lab at the University of Kentucky.


Zip Load Modeling For Single And Aggregate Loads And Cvr Factor Estimation, Yiqi Zhang, Yuan Liao, Evan S. Jones, Nicholas Jewell, Dan M. Ionel Aug 2021

Zip Load Modeling For Single And Aggregate Loads And Cvr Factor Estimation, Yiqi Zhang, Yuan Liao, Evan S. Jones, Nicholas Jewell, Dan M. Ionel

Electrical and Computer Engineering Presentations

ZIP load modeling has been used in various power system applications. The aggregate load modeling is common practice in utility companies. However, little research has been done on the theoretical formulation of the aggregate load. This paper formulates the aggregate ZIP load model using the single ZIP load model. The factors that may affect aggregate ZIP load estimation are studied. Common ZIP parameter estimation methods including least squares method, optimization method and neural network method have been used in this paper to estimate ZIP parameters. The case studies are based on the IEEE 13-bus and 34-bus system built in OpenDSS. …


Aqueous Photochemistry Of 2-Oxocarboxylic Acids: Evidence, Mechanisms, And Atmospheric Impact, Marcelo I. Guzman, Alexis J. Eugene Aug 2021

Aqueous Photochemistry Of 2-Oxocarboxylic Acids: Evidence, Mechanisms, And Atmospheric Impact, Marcelo I. Guzman, Alexis J. Eugene

Chemistry Faculty Publications

Atmospheric organic aerosols play a major role in climate, demanding a better understanding of their formation mechanisms by contributing multiphase chemical reactions with the participation of water. The sunlight driven aqueous photochemistry of small 2-oxocarboxylic acids is a potential major source of organic aerosol, which prompted the investigations into the mechanisms of glyoxylic acid and pyruvic acid photochemistry reviewed here. While 2-oxocarboxylic acids can be contained or directly created in the particles, the majorities of these abundant and available molecules are in the gas phase and must first undergo the surface uptake process to react in, and on the surface, …


Micrornas As Biomarkers For Predicting Complications Following Aneurysmal Subarachnoid Hemorrhage, Wang-Xia Wang, Joe E. Springer, Kevin W. Hatton Aug 2021

Micrornas As Biomarkers For Predicting Complications Following Aneurysmal Subarachnoid Hemorrhage, Wang-Xia Wang, Joe E. Springer, Kevin W. Hatton

Sanders-Brown Center on Aging Faculty Publications

Aneurysmal subarachnoid hemorrhage (aSAH) is a high mortality hemorrhagic stroke that affects nearly 30,000 patients annually in the United States. Approximately 30% of aSAH patients die during initial hospitalization and those who survive often carry poor prognosis with one in five having permanent physical and/or cognitive disabilities. The poor outcome of aSAH can be the result of the initial catastrophic event or due to the many acute or delayed neurological complications, such as cerebral ischemia, hydrocephalus, and re-bleeding. Unfortunately, no effective biomarker exists to predict or diagnose these complications at a clinically relevant time point when neurologic injury can be …


Intra-Arterial Combination Therapy For Experimental Acute Ischemic Stroke, Michael E. Maniskas, Jill M. Roberts, Amanda A. Gorman, Gregory J. Bix, Justin F. Fraser Aug 2021

Intra-Arterial Combination Therapy For Experimental Acute Ischemic Stroke, Michael E. Maniskas, Jill M. Roberts, Amanda A. Gorman, Gregory J. Bix, Justin F. Fraser

Neurosurgery Faculty Publications

Acute ischemic stroke continues to devastate millions of individuals worldwide. Current treatments work to restore blood flow but not rescue affected tissue. Our goal was to develop a combination of neuroprotective agents administered intra-arterially following recanalization to target ischemic tissue. Using C57Bl/6J male mice, we performed tandem transient ipsilateral middle cerebral/common carotid artery occlusion, followed by immediate intra-arterial pharmacotherapy administration through a standardized protocol. Two pharmacotherapy agents, verapamil and lubeluzole, were selected based on their potential to modulate different aspects of the ischemic cascade; verapamil, a calcium channel blocker, works in an acute fashion blocking L-type calcium channels, whereas lubeluzole, …


Association Between Self-Reported Survey Measures And Biomarkers Of Second-Hand Tobacco Smoke Exposure In Non-Smoking Pregnant Women, Meiman Maggie Chen, Su-Er Guo, Chi-Pin Yuan, Chizimuzo T. C. Okoli, Yen-Chi Liao Aug 2021

Association Between Self-Reported Survey Measures And Biomarkers Of Second-Hand Tobacco Smoke Exposure In Non-Smoking Pregnant Women, Meiman Maggie Chen, Su-Er Guo, Chi-Pin Yuan, Chizimuzo T. C. Okoli, Yen-Chi Liao

Nursing Faculty Publications

Second-hand tobacco smoke (SHS) causes adverse health outcomes in adults. Further studies are needed to evaluate psychosocial SHS exposure measures in comparison to SHS exposure biomarkers, particularly in pregnant women. This study aimed to compare self-reported SHS exposure to urinary cotinine levels in pregnant women. A cross-sectional correlation design was conducted using a convenience sample of 70 non-smoking pregnant women. Measures included self-reported questionnaires and laboratory confirmation of cotinine levels in the urinary samples. Multiple regression analysis was used to assess the correlation after controlling for potential confounding variables. The average level of urinary cotinine among non-smoking pregnant women was …


Poverty And Paternal Education Associated With Infant Safe Sleep Intentions In A Peri-Urban Community In Ecuador, Hartley Feld, Janeth Ceballos Osorio, Marisol Bahamonde, Thomas Young, Pablo Boada, Mary Kay Rayens Aug 2021

Poverty And Paternal Education Associated With Infant Safe Sleep Intentions In A Peri-Urban Community In Ecuador, Hartley Feld, Janeth Ceballos Osorio, Marisol Bahamonde, Thomas Young, Pablo Boada, Mary Kay Rayens

Nursing Faculty Publications

Ecuador’s annual mortality rate from SIDS is 0.4 per 100 000 people, 4 times higher than neighboring countries Peru, Bolivia, and Brazil. Modifying the infant sleep environment toward safe practice has been demonstrated to be the most effective risk reduction strategy in reducing mortality from SIDS and little is known about sleep practices in Ecuador. The purpose of this study is to describe baseline infant sleep intentions of pregnant women in a peri-urban, low resource community in Ecuador. We also aim to identify demographic and psychosocial factors associated with suboptimal sleep practices in this context to develop long-term strategies to …


Effect Of Fungicide Application On Seed Yield Of Perennial Ryegrass, Piotr Goliński Aug 2021

Effect Of Fungicide Application On Seed Yield Of Perennial Ryegrass, Piotr Goliński

IGC Proceedings (1977-2023)

In four plot experiments established according to random blocks, application effectiveness of propiconazol + carbendazim (Tilt), propiconazol + fenpropimorph (Archer), flusilazol + carbendazim (Alert) and epoxiconazol + crezoxim-metil (Juwel) pesticides regarding the infection by fungal diseases of plant inflorescence structure, biological floret site utilisation, thousand seed weight and harvested seed yield of perennial ryegrass cv. Anna (2n) and cv. Maja (4n) was analysed. The Archer preparation was found to be the most effective, both in the case of Anna and Maja cultivars. Its application was found to increase seed yield in Anna and Maja cultivars by, respectively, 21,5% and 14,5%. …


Genetic Control Of Parthenogenesis In Kentucky Bluegrass: Results From A Sexual X Apomictic Cross, E. Albertini, G. Barcaccia, A. Porceddu, D. Rosellini, Mario Falcinelli Aug 2021

Genetic Control Of Parthenogenesis In Kentucky Bluegrass: Results From A Sexual X Apomictic Cross, E. Albertini, G. Barcaccia, A. Porceddu, D. Rosellini, Mario Falcinelli

IGC Proceedings (1977-2023)

Apomixis, as it exists in Poa pratensis L., permits to combine genotype fixation with propagation by seed. The process of apomictic seed production involves the formation of embryo sacs without meiotic reduction (apospory) and embryos without egg cell fertilization (parthenogenesis). Further information on the genetic control of apomixis was obtained by analyzing aposporous parthenogenesis and the segregation of molecular markers in a progeny resulting from a “sexual” (S) x “apomictic”(A) cross. Data from the 35 F1 plants examined so far have shown that parthenogenesis segregated 1:1, confirming control by a dominant gene, simplex in the parthenogenetic parent. Analysis of …


Effects Of Water Stress On Seed Production In Ruzi Grass (Brachiaria Ruziziensis Germain And Everard), N. Wongsuwan, A. C. P. Chu, B. R. Watkin Aug 2021

Effects Of Water Stress On Seed Production In Ruzi Grass (Brachiaria Ruziziensis Germain And Everard), N. Wongsuwan, A. C. P. Chu, B. R. Watkin

IGC Proceedings (1977-2023)

Water stress at different stages of reproductive development influenced seed yield in Ruzi grass differently. Under mild water stress, the earlier in the reproductive developmental stage the stress was applied (before ear emergence) the faster the plants recovered and the less the ultimate damage to inflorescence structure and seed set compared with the situation where water stress occurred during the later stages after inflorescences had emerged. Conversely, severe water stress before ear emergence had a severe effect in damaging both inflorescence numbers and seed quality. Permanent damage to the reproductive structures resulted in deformed inflorescences. Moreover, basal vegetative tillers were …


Effect Of Temperature On Phenology In Triple-Awned Grass (Stipagrostis Plumosa), Hossein Azarnivand, H. Dastmalchi Aug 2021

Effect Of Temperature On Phenology In Triple-Awned Grass (Stipagrostis Plumosa), Hossein Azarnivand, H. Dastmalchi

IGC Proceedings (1977-2023)

Phenology of triple-awned grass in different stages of vegetative growth, flowering and seed falling was investigated. Each phenological stage was related to minimum and maximum air and soil surface temperatures. Soil surface temperature was measured two times per day during different seasons. Climate data were obtained from the nearest weather station. The study was carried out in sand dunes of band-e-rig of Kashan in the central region of Iran. This species is important in terms of wind erosion control and livestock feeding in arid areas. The results showed that air temperatures ranged from –22 oC to 41.5 oC …


Morphogenesis And Growth Analysis Of Mombaçagrass (Panicum Maximum) During Establishment And Regrowth, Carlos A. M. Gomide, J. A. Gomide, C. A. M. Huaman Aug 2021

Morphogenesis And Growth Analysis Of Mombaçagrass (Panicum Maximum) During Establishment And Regrowth, Carlos A. M. Gomide, J. A. Gomide, C. A. M. Huaman

IGC Proceedings (1977-2023)

Mombaçagrass grown in pots was evaluated regarding leaf appearance, elongation and senescence rates; leaf area indices, photosynthetcly active radiation (PAR) interception and the growth indices: leaf area ratio (LAR), net assimilation rate (NAR) and relative growth rate (RGR). Three growths were considered: seminal growth and regrowth after harvest take on the 16th and 37th day of the seminal growth.

The seminal growth exhibited the highest values for leaf appearance, elongation and senescence rates as compared to aftermath growths. LAI rose linearly from the 20th to the 77th day of the seminal growth, as well as during …


Tillering Dynamics In Mombaça Grass (Panicum Maximum, Jacq.) Under Grazing, E. M. Coelho, V. R. Herling, M. A. Gomes, R. J. Schmidt, C. G. Lima Aug 2021

Tillering Dynamics In Mombaça Grass (Panicum Maximum, Jacq.) Under Grazing, E. M. Coelho, V. R. Herling, M. A. Gomes, R. J. Schmidt, C. G. Lima

IGC Proceedings (1977-2023)

An experiment was conducted in Pirassununga, Southeastern Brazil, to observe tillering pattern of Mombaça grass (Panicum maximum Jacq.) after grazing. A complete randomized block design was used with treatments arranged in factorial (3 herbage allowances X 2 grazing periods). There was high and positive correlations between the total tiller population and the number of tillers until the third week after grazing, giving evidence of a higher tillering until the second week and a slight reduction on the third one. The Mombaça grass tillering dynamics alters along the weeks according the allowance level adopted.


Response Of Mombaça Grass (Panicum Maximum Jacq.) To Nitrogen Doses And Clipping Frequency, Gustavo J. Braga, P. H. C. Luz, V. R. Herling, R. J. Schmidt, C. G. Lima Aug 2021

Response Of Mombaça Grass (Panicum Maximum Jacq.) To Nitrogen Doses And Clipping Frequency, Gustavo J. Braga, P. H. C. Luz, V. R. Herling, R. J. Schmidt, C. G. Lima

IGC Proceedings (1977-2023)

The present experiment had the objectives of determining the response of Mombaça grass (Panicum maximun Jacq.) to three levels of nitrogen fertilizer (0, 250, 500 kg/ha) and two clipping frequencies (28 and 42 days). Dry matter yield (DMY), density and the average weight of tillers and the mean stage count (MSC), value that represents the quantity of the plant phenological development were evaluated. Nitrogen levels affected DMY, with the 500 kg/ha of N resulting in highest yield, and highest MSC as well. The number of tillers responded positively until the 250 kg/ha level. The 42-day frequency gave higher numbers …


Herbage Allowance And Nitrogen Fertilization Effects On Morphological Characteristics Of Paspalum Notatum Flügge, P. Boggiano, G. E. Maraschin, Carlos Nabinger, J. Riboldi, Mónica Cadenazzi Aug 2021

Herbage Allowance And Nitrogen Fertilization Effects On Morphological Characteristics Of Paspalum Notatum Flügge, P. Boggiano, G. E. Maraschin, Carlos Nabinger, J. Riboldi, Mónica Cadenazzi

IGC Proceedings (1977-2023)

The grazing study was conducted at the Estação Experimental Agronomica – UFRGS, 30o S, on a native pasture, to evaluate the leaf area index and structural morphological traits of bahiagrass (Paspalum notatum Fl.), within the requirements of a Central Composite Rotatable experimental design, providing for equal precision, with two blocks, encompassing two factors at five levels each, namely: Herbage Allowance (HA) = 4.0; 5.5; 9.0; 12.5 and 14.0 kg green dry matter per 100 kg liveweight per day (% LW), in association with Nitrogen (N) fertilization levels of 0; 30; 100; 170 and 200 kg ha-1 as …


Influence Of Fertilization On Botanical Composition And Productivity Of Rangeland In A Semi-Arid Climate Of South Africa, Hennie A. Snyman, I. B. Oosthuizen Aug 2021

Influence Of Fertilization On Botanical Composition And Productivity Of Rangeland In A Semi-Arid Climate Of South Africa, Hennie A. Snyman, I. B. Oosthuizen

IGC Proceedings (1977-2023)

The objective of this study was to determine the short-term response of rangeland to fertilization rangeland (all combinations of 0; 10; 30 and 50 kg ha-1 nitrogen, with 0 and 10 kg ha-1 of phosphorus) in terms of dry matter production and botanical composition. After three years of fertilization, the botanical composition of the high-N fertilized plots changed completely from a climax to sub-climax vegetation. Wire grass (Elionurus muticus) showed the greatest decrease in frequency (62%) due to N fertilization. Phosphorus fertilization had an insignificant influence on species composition over the three years. The increase (P< 0.01) in production with increased N fertilizer, peaked in the second season, declining afterwards. With N and P fertilizer applied together, the production increased constantly and peaked in the last season. After three years the production increased (P≤ 0.01) with the application of N together with P, compared to the applying of only N. The higher the amount of fertilizer, the more sensitive to drought the climax grasses became. The results confirm the vulnerability of native grasses in dry areas, due to change in soil fertility.