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Winter Survival And Physiology Of Contrasting Fall Dormancy Selections Of Alfalfa, J J. Volenec, S M. Cunningham, L R. Teuber

IGC Proceedings (1977-2023)

Our objective was to determine the physiological changes that accompany selection from within a germplasm for contrasting fall dormancy reaction. Selection for greater fall dormancy improved winter survival of CUF 101 from 1 to 93%. The more fall dormant CUF 101 had higher sugar concentrations in buds and roots. Roots of the more fall dormant CUF 101 also contained higher soluble protein concentrations when compared to the other CUF 101 germplasms. Root protein extracts obtained in Dec. from the more fall dormant CUF 101 contained at least one polypeptide not found in protein extracts of the other CUF 101 germplasms. …

Root Nitrogen Cycling And Alfalfa Stress Tolerance, J J. Volenec, B C. Joern, L D. Barber, S M. Cunningham, A Ourry

IGC Proceedings (1977-2023)

Our hypothesis is that certain root N pools are utilized preferentially during the early shoot regrowth. Our objective was to determine the relative contribution of crown N, root N, and specific root N pools to shoot regrowth after defoliation. We used 15N to follow N into and out of crowns, roots, and specific root N pools, to regrowing shoots after defoliation. The low molecular weight N pool (amino acids, inorganic N,...) acquired 15N rapidly within 2 d of N application. Movement of 15N into the protein-N and insoluble-N pools was delayed initially, but continued until 8 d after N application. …

Phyllochron Development In Cool-Season Forage Grasses, A B. Frank, J D. Berdahl, J F. Karn

IGC Proceedings (1977-2023)

The purpose of this study was to evaluate the relationship between grass leaf insertion rate and accumulated growing degree-days, and determine the phyllochron for five perennial forage grass species and two cultivars of each species. Species field seeded in solid stands were crested wheatgrass [Agropyron desertorum (Fisch. ex. Link) Schult.], intermediate wheatgrass, [Thinopyrum intermedium Barkw. & Dewey:Syn:A. intermedium (Host) Brauv], western wheatgrass [Pascopyrum smithii (Rybd) L ve], green needlegrass (Stipa viridula Trin.), and smooth bromegrass (Bromus inermis Leyss). Species phyllochron differences ranged from 77 GDD for Mandan 404 smooth bromegrass to 114 GDD for Lodorm …

Response To Drought Of White Clover Lines Selected For Different Stolon Morphologies, H D. Karsten, J R. Caradus, D R. Woodfield

IGC Proceedings (1977-2023)

White clover (Trifolium repens L.) lines were selected from within large and small-leaved cultivars of Grasslands Kopu and Grasslands Tahora, respectively, for long or short internodes, and for high or low branching frequency from plants grown in sun and shade (50% full sunlight). Lines were compared for drought tolerance in a perennial ryegrass (Lolium perenne L.) sward in boxes. Prior to imposing drought branching frequency selections did not differ in branching frequency, although the low branching frequency selection had a higher percentage of rooted nodes. After an imposed drought treatment sun-selected lines grew better than shade-selected lines relative …

Kentucky Bluegrass Floral Induction And Cultivar Response To Mechanical Removal Of Harvest Residue, G A. Murray, J B. Swensen

IGC Proceedings (1977-2023)

Open-field burning of post-harvest residue from Kentucky bluegrass (Poa pratensis L.) seed fields is being phased out in Washington, USA and may be banned in Idaho. Burning encourages early fall regrowth and timely completion of fall floral induction. Cultivars have different floral induction requirements and respond differently to mechanical residue removal. Our objective was to determine if length of fall floral induction requirement was related to seed yield when post-harvest residue was removed by crewcut vacuum sweeping. Floral induction requirements were not related to first-or second-year seed yields. Third-year seed yield of cultivars with long floral induction requirements declined …

The Influence Of Intensity Of Tree Thinning On The Redistribution Of Soil Water In Southern African Mopani Veld, G N. Smit, N F.G. Rethman, A Moore, A Le Roux, J S. Swart

IGC Proceedings (1977-2023)

The investigation was conducted on a densely wooded area in the Mopani veld of South Africa. Six plots were subjected to different intensities of tree thinning, ranging from a totally cleared plot (0 %) to plots thinned to the equivalent of 10%, 20%, 35%, 50% and 75% of the leaf biomass of a control plot (100%). Soil water measurements were taken at six different depths to a depth of 825 mm. The infiltration of rain water and redistribution within the soil profile exhibited marked differences between experimental plots. The soil water was predominantly held at a very shallow depth ( …

Relationship Of Visual And Quantitative Methods Of Grass Sward Development, R B. Mitchell, L E. Moser, K J. Moore

IGC Proceedings (1977-2023)

The objective of this study was to determine the relationship between visual and quantitative estimates of the morphological development of perennial grass swards. Pure stands of intermediate wheatgrass [Thinopyrum intermedium (Host) Barkw. & D.R. Dewey] and switchgrass (Panicum virgatum L.) were hand-clipped to ground level at 2-wk intervals in 1991 at Mead, NE, morphologically classified as mean stage count (MSC), and visually estimated for sward development. Visual estimations of sward development for both species were representative of quantitative measurements during vegetative growth. However, as sward development advanced to the elongation and heading stages, visual methods over-estimated the population …

Morphological Development Rates Of Perennial Forage Grasses, R B. Mitchell, L E. Moser, K J. Moore, D D. Redfearn

IGC Proceedings (1977-2023)

The objective of this study was to determine the rate of change in the morphological development of switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerardii Vitman). Pure stands of each species were sampled at weekly intervals in 1990 and 1991 at Mead, NE, and morphologically classified as mean stage count (MSC) and mean stage weight (MSW). Linear day of the year equations accounted for 94% of the variation in switchgrass MSC and MSW. Switchgrass MSC and MSW increased at an average rate of 0.0204 and 0.0234 units per day, respectively. Linear day of the year equations accounted …

Fertilizer Nitrogen And Morphogenetic Response In Avena Sativa And Lolium Multiflorum, F Lattanzi, M A. Marino, A Mazzanti

IGC Proceedings (1977-2023)

A field experiment was carried out at the EEA Balcarce, INTA, Argentina (37° 45’LS, 58° 18’LW) to determine whether Leaf Appearance Rate (LAR) was affected by N fertilization in Italian ryegrass (Lolium multiflorum Lam.) and forage oats (Avena sativa). N treatments (0, 50, 100, 150, 200 and 250 kg N ha-1) were applied in winter 1995, after a defoliation. Subsequently, number of leaves per tiller was determined on 45 labelled tillers in each treatment twice a week. LAR was calculated as the slope of the linear regression of number of leaves on thermal time (air temperature, base …

Allocation Of Carbon-14 To Roots Of Different Ages In Perennial Ryegrass (Lolium Perenne L.), C Matthew, W D. Kemball

IGC Proceedings (1977-2023)

The objective of this study was to provide information on how current photosynthate allocated to the root system in perennial ryegrass (Lolium perenne L.) is distributed among individual roots at differing nodal positions. Mature single ryegrass tillers were transplanted in September 1993 to glass house pots and three months later four of the plants were supplied with 14CO2. Individual roots from these radioactively-labeled plants were identified according to their nodal position on the tiller axis and amount of radiocarbon in each root quantified for root tip segments and for the remainder of the root axis. Similar plants were destructively …

The Analysis Of Dynamic Interaction In Legume Binary Mixture Under Controlled Conditions Of Irrigation And Clipping, M S. Vrahnakis, B Noitsakis, Z Koukoura

IGC Proceedings (1977-2023)

The objective of this study was to analyse the type of interference that occurred between the annual legume species, purple clover (Trifolium purpureum L.) and narrow leaved crimson clover (Trifolium angustifolium Loisel. ), growing in mixed conditions under two different watering regimes and two different clipping treatments. A replacement series experiment was conducted in pots placed in the field. The above ground biomass (gr/plant) were measured. The recently proposed Inverse Linear Model was implied in order to analyse the competitive interaction between the above species. The results suggest that Tr. purpureum was the superior competitor to Tr. angustifolium …

Predicting The Potential Distribution Of Pseudococcus Longispinus (Targioni-Tozzetti) (Hemiptera: Pseudococcidae) In South Korea Using A Climex Model, Su Bin Kim, Soo-Jung Suh

Insecta Mundi

Pseudococcus longispinus (Targioni-Tozzetti) (Hemiptera: Pseudococcidae) is a widely-distributed pest that feeds on many economically important hosts, particularly tropical fruits and ornamentals. The potential distribution of this mealybug pest in South Korea remains a primary concern because of its high incidence of interceptions screened during inspection. Hence, this species prompted a modelling effort to assess its potential risk of introduction. Potential risk maps were developed for this pest with a CLIMEX model based on occurrence records under environmental data. The potential distribution of these pests in South Korea in the 2020s, 2050s and 2090s was projected based on the RCP 8.5 …

The Genus Centris Fabricius In Cuba, With A New Record And The Description Of A New Species (Hymenoptera: Apoidea: Anthophila), Julio A. Genaro, Dayron Breto

Insecta Mundi

Members of the genus Centris Fabricius (Hymenoptera: Apoidea: Anthophila) constitute a significant component of the Neotropical (including insular) bee fauna, exhibiting high species richness, a moderate to large body size, and extensive interactions with various important plant groups. Females of most species possess specialized morphology adapted for collecting oils from flowers. This study documents the presence of the genus in Cuba, recognizing six species: C. aethiops Cresson, C. cornuta Cresson, C. fulviventris Cresson, C. poecila Lepeletier, C. taina Genaro and Breto new species, and C. tarsata F. Smith. Detailed information is provided for …

Diagnosis Of Spilococcus Pacificus (Borchsenius, 1949) And An Updated List Of Scale Insects (Hemiptera: Coccomorpha) On Pears (Pyrus L.: Rosaceae) In South Korea, Jungyoun Ji, Soo-Jung Suh

Insecta Mundi

Pears, Pyrus pyrifolia (Burm.f.) Nak. (Rosaceae) are one of the most widely grown fruit trees in South Korea. Approximately 11% of the total pear production in 2022 was exported to countries such as the United States and Vietnam. Exported pears must be free of pest species that are considered of quarantine importance by the importing countries. Herein, a list of scale insects (Hemiptera: Coccomorpha) associated with pear trees is updated. Additionally, Spilococcus pacificus (Borchsenius) is added to the list of mealybugs affecting pears in South Korea and is briefly diagnosed based on non-type specimens and illustrated using photographs. Information on …

Enhancement Of Soybean Growth And Disease Resistance Through Seed-Priming Strategy, Francisco Javier Valle

LSU Master's Theses

Disease pressure and other environmental stresses, especially increasing temperature and drought incidence, accompanied with global climatic change have presented hard challenges to Louisiana soybean producers. The objective of this study was to explore the efficacy of seed priming techniques as new alternatives to improve soybean crop protection to reduce the amount of yield losses caused by biotic and abiotic stresses. In this study, five chemicals were used as priming agents at different concentrations (0.1 mM, 1 mM, and 10 mM) to evaluate their effectiveness in enhancing disease tolerance and yield in soybeans. A seed priming procedure was developed by partially …

Settling Preference Of Nipponaclerda Biwakoensis (Hemiptera: Aclerdidae) On Phragmites Australis Stems, Alexia Catherine Desoto

LSU Master's Theses

Phragmites australis, a wetland grass that stabilizes the Louisiana coastline, has been undergoing a major die-off near the Mississippi River Delta (MRD) since the autumn of 2016. One suspected cause for this plant decline is the attack of an invasive scale insect, Nipponaclerda biwakoensis. We lack information on the host preference of the crawlers, the life stage that decides where to settle and when to start feeding on the plant. The objectives of this study were to identify what positions along the vertical stem N. biwakoensis prefers to settle and what host-plant traits may be influencing this choice. We recorded …

Soil Health Cycle, Bijesh Maharjan, Saurav Das, Vesh R. Thapa, Bharat Sharma Acharya

Department of Agronomy and Horticulture: Faculty Publications

Soil health is pivotal to agricultural sustainability. Promoting and sustaining soil health management is challenging since it involves many interdependent components and steps and is an iterative process. Herein, the soil health cycle (SHC) is proposed as a soil health management cycle encompassing human dimensions, management practices, and their effects on soil health indicators (SHIs), leading to subsequent impacts on soil functions. The SHC provides a structure for an iterative testing of changes to improve soil health. A systematic review of research publications was also conducted using the Web of Science database supplemented by Elicit AI and Scopus API searches …

Hira Gene Mutation In Arabidopsis Via Crispr, Kelly Chen, Claire Shippy, Tara Phelps-Durr

SACAD: Scholarly Activities

The purpose of this study is to mutate the Histone Repressor A (HIRA) gene in a mustard plant (Arabidopsis) using CRISPR technology. HIRA is a chromatin-remodeling protein that is required for proper development in both plants and animals. Creating new changes (mutations) in HIRA will help us better understand the mechanism of how HIRA regulates transcription, which is important for understanding developmental disorders in animals, as well as how improper development leads to a reduction in crop yields in plants

Where Have All The Flowers Gone? A Call For Federal Leadership In Deer Management In The United States, Bernd Blossey, Darragh Hare, Donald M. Waller

Aspen Bibliography

Forests in the United States continue to lose biodiversity and many fail to regenerate due to high deer (family Cervidae) abundance. Declines in biodiversity and overall ecosystem health due to high deer populations increases prevalence of wildlife and human diseases associated with increasing tick abundances and decreases forest resilience and the ability to deliver benefits provided by healthy ecosystems. In the eastern and midwestern United States, white-tailed deer (Odocoileus virginianus) are the main stressor, while in the western U.S. elk (Cervus elaphus) and black-tailed and mule deer (Odocoileus hemionus) can become equally problematic. Federal …

An Interdisciplinary Experience, Reyna Vergara, Michael Dodson

OUR Assignment Repository

This proposal showcases the success of an interdisciplinary approach. It provides an overview of a project titled: "Cacao and Chocolate: A Powerful Legacy." It took place during Hispanic Heritage Month in 2023. The project aimed to explore the rich and multifaceted legacy of cacao and chocolate in Latin America, incorporating perspectives from various academic disciplines, including public history, chemistry, Spanish language, graphic design, culinary arts, and family science. The interdisciplinary nature of the project highlights the power of collaboration in research and education, serving as a model for integrating diverse fields of study.

The project was divided into two main …

The Plant Disease Triangle Facing Climate Change: A Molecular Perspective, Charles Roussin-Léveillée, Christina A. M. Rossi, Christian Castroverde, Peter Moffett

Biology Faculty Publications

No abstract provided.

Impacts Of Altitude On Plant Green Leaf, Fresh Litter, And Soil Stoichiometry In Subtropical Forests, Dehuang Zhu, Yan Zhou, Suhong Peng, Weiping Hua, Bin Luo, Dafeng Hui

Biology Faculty Research

BackgroundEcological stoichiometric characteristics of carbon (C), nitrogen (N), phosphorus (P), and potassium (K) serve as crucial indicators of nutrient cycling and limitation in terrestrial ecosystems. However, our current understanding of stoichiometric characteristics in subtropical forests and their response to different climate conditions is still limited.MethodsWe selected six altitudes ranging from 700 m to 1,200 m to simulate different climate conditions of an evergreen broadleaf forest in Wuyi Mountain, Fujian Province, China. We investigated C, N, P, and K stoichiometry and homeostasis in the green leaves, newly senesced leaf litter (fresh litter), and soil of this forest.ResultsLeaf P and K levels …

2024 Woy: Turtleheads And Bumblebees, W. John Hayden

Biology Faculty Publications

No abstract provided.

Joint Environmental And Social Benefits From Diversified Agriculture, Laura Vang Rasmussen, Ingo Grass

Earth and Environmental Sciences Faculty Publications

Agricultural simplification continues to expand at the expense of more diverse forms of agriculture. This simplification, for example, in the form of intensively managed monocultures, poses a risk to keeping the world within safe and just Earth system boundaries. Here, we estimated how agricultural diversification simultaneously affects social and environmental outcomes. Drawing from 24 studies in 11 countries across 2655 farms, we show how five diversification strategies focusing on livestock, crops, soils, noncrop plantings, and water conservation benefit social (e.g., human well-being, yields, and food security) and environmental (e.g., biodiversity, ecosystem services, and reduced environmental externalities) outcomes. We found that …

What Soil Is Worth: A Cost-Benefit Framework Analysis Of Syntropic Farming, Aubrey Kettley

Independent Study Project (ISP) Collection

Syntropic farming, a type of regenerative agriculture, models its farming system after a forest. This type of farming prioritizes soil health while also providing a varied yield of crops. Because it is a fairly new system globally, little research has been done on the economic impacts of syntropic farming, and therefore the feasibility of scaling up regenerative systems like this. This study aims to analyze the economic feasibility of this system through a literature review and a cost-benefit analysis framework. The results highlight the applicability, environmental advantage and economic feasibility of the system. Based on the presented framework, the short …

Structural Responses To Land Use In Pollination Networks: Effects Of Biodiversity And Alien Plants In The Ecuadorian Chocó, Eric Abrahams

Independent Study Project (ISP) Collection

As a globally recognized hotspot of biodiversity, the Ecuadorian Chocó Andino region is extremely important for research and conservation. However, little research has been done regarding the mutualistic networks that sustain this ecosystem. The analysis of plant-pollinator networks helps us understand how ecosystems respond to change and is vital to conserving ecological productivity across multiple spatial scales. This study establishes a baseline for pollinator network structure across a land use gradient near the western montane cloud forest in Ecuador. Plants and pollinators were sampled along 11 transects in farms, communities, roads in the Río Manduriacu valley. Weedy herbs dominated overall, …

Variations In Salinity And Forest Structure Between Marginal And Cloistered Mangrove Forests In Boca Del Drago, Bocas Del Toro, Panama, Mary Elizabeth Hodge

Independent Study Project (ISP) Collection

Mangroves are incredibly important ecosystems that have an outsized impact on their surroundings, providing crucial ecosystem services like carbon sequestration and coastal protection. At the same time, mangroves are some of the most threatened habitats due to their valuable position along tropical coastlines. Globally, mangrove forests are deforested and degraded by aquaculture, tourism developments, urbanization, and overharvesting. Due to high rates of mangrove loss, mangrove deforestation is now illegal in Panama, though this legislation is inconsistent and allows for exceptions, especially in tourism developments. This study aims to probe the impacts of localized coastal developments on a small mangrove forest …

Vascular Epiphyte Population Dynamics Within Human-Modified Landscapes Of Guadalupe, Cerro Punta, Chiriquí, Panamá, Lucine Tashjian

Independent Study Project (ISP) Collection

Epiphytes are plants that grow on other plants non-parasitically, and globally, epiphytes compose a very large and diverse group. They are especially abundant and species-rich in the tropics- particularly, in tropical montane forest ecosystems. Human population growth in the tropics, however, has resulted in significant declines in forest cover with land being converted largely for agricultural purposes. Studies on epiphytes have traditionally been undertaken in pristine, undisturbed forest ecosystems, yet terrestrial land conversion has increased the need to understand the value of human-modified ecosystems for epiphytic populations and biodiversity conservation. This study sought to understand the relationship between human modification …

Providing Pest Management Education For Home Gardeners In Utah, Nick Volesky, Marion Murray

Outcomes and Impact Quarterly

In January 2024, Utah State University (USU) Extension's Integrated Pest Management (IPM) program launched a three-part class series targeting Utah's home gardeners. The goal was to enhance their abilities in identifying and managing insect and plant diseases. With over 200 participants, the series notably increased the knowledge of attendees. This initiative aligns with the USU Extension IPM program's mission to promote sustainable pest management practices across Utah, evidencing its commitment to environmental stewardship and community education.

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley O. Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch

School of Integrative Biological & Chemical Sciences Faculty Publications

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …