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Varietal Difference In The Pre‐Germination Flooding Tolerance Of Commercial Cultivars Of Silage Corn And The Availability Of A Ridge‐Making Seeder For The Avoidance Of Wet Injury To Corn Seeds, Tsutomu Kanno, Souichiro Morita, Shunji Kurokawa, Setsuro Sato, Yoshiro Mano, Toshihiko Ibuki, Noritoshi Sumida, Hidehiko Inoue, Seiji Nakao, Hisashi Hosokawa

IGC Proceedings (1977-2023)

No abstract provided.

Effects Of Storage Conditions On The Germinability Of Seeds Of Three Different Browse Plants, Alaba O. Jolaosho

IGC Proceedings (1977-2023)

No abstract provided.

Raising Seedling Of Longstalk Peach, Ming Jia, Gele Qing, Yuzhi Wang

IGC Proceedings (1977-2023)

No abstract provided.

The Role Of The Lens In Controlling Physical Dormancy Breakdown In Three Legume Species, X. W. Hu, Yanrong Wang

IGC Proceedings (1977-2023)

No abstract provided.

Different Priming Treatments To Influence The Germination Of Atriplex L., Shengrong Hu, Dandan Zhou, Yong Gao

IGC Proceedings (1977-2023)

No abstract provided.

Effect Of Drought Stress On The Viability Of Wild Lespedeza Dahurica Seeds, Zhibing Hou, Xiang Zhao, Zhiming Bai

IGC Proceedings (1977-2023)

No abstract provided.

Volume 4, Chapter 1-15: Aquatic And Wet Marchantiophyta, Pallaviciniales, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.

Center For Grassland Studies, May 2021

Center for Grassland Studies: Newsletters

Contents

Prescribed Burn Associations by Brian Teeter

Center for Grassland Studies Policy Advisory Committee

Director's Column by Walt Schact (Interim Director)

Looking for a Career in Conservation – How to Apply in USAJOBS for NRCS Positions by Mary Reece

Monitoring Sandhills Rangelands: A Key Step in Understanding Plant Community Dynamics by Mitch Stephenson

Development of Novel Plant Fluorescence Based Techniques for Remote Assessment of Grasslands and Pastures Health and Resilience by Anastasios Mazis

UNL PGA Golf Management Alumni Among Nebraska Section Award Winners by Brad Goetsch

Nebraska’s Grassland Legacy by Walt Schacht

Nebraska Grazing Conference: Save the Date, August 9-11, …

Loblolly Pine (Pinus Taeda) Leaf-Level Physiology And The Influence Of Genotype, Drought, And Thinning, Norman Jesse Cone Iv

Master's Theses

The Southeastern U.S. is known as the “Wood Basket” for producing the vast majority of U.S. timber, but projected increases in the frequency of severe drought events could threaten timber plantations. Loblolly pine (Pinus taeda) is the principle timber species of the southeast and is distributed across the Atlantic Coastal Plains and west into Texas. Western Gulf states (LA, TX, AR, and OK) lie at the edge of the range for loblolly pine and are particularly vulnerable to any changes in precipitation or temperature. Current research suggests two main methods to increase plantation drought resistance: plant drought resistant seedlings or …

Marketing Agroforestry Products: Lessons From Producers

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

This publication shares producer experiences with marketing agroforestry products, including how producers entered — or created — the markets for their products. These individual stories highlight a diversity of experiences, from family-run farms to intermediaries assisting with market access. United States Department of Agriculture (USDA) and other federal, state, and local programs can provide capital or technical assistance to farmers at different phases of market development. The case studies in this publication highlight programs and resources available through USDA.

While marketing tree crops and non-timber forest products can be a challenge for producers, there is room for growth and opportunities …

Characterization, Incidence, And Epidemiology Of Two Novel Strawberry Rhabdoviruses, Ava Wait

Graduate Theses and Dissertations

Strawberry is the most important berry crop, grown in most temperate regions around the world. In the early 2000s and in 2012-2013, viral disease devastated strawberry production in California and Florida respectively; causing multimillion dollar losses. This occurred because viruses were moving in the field undetected. The modern strawberry (Fragaria x ananassa Duch.) is tolerant to single and double infections; yet when several viruses infect plants, symptoms as severe as plant death can occur. To prevent future epidemics, the use of virus-tested planting materials is essential. In 2019, rhabdovirus-like sequences were detected in strawberry using a combination of high-throughput sequencing …

Quality Determinates Of Rice Price In Open Bag Markets In Sub-Saharan Africa, Bailey Peterson-Wilhelm

Graduate Theses and Dissertations

Weaknesses in the grades and standards system in low-income countries across Sub-Saharan Africa undermine the transparency of agricultural markets. In the Democratic Republic of the Congo (DRC), Ghana and Mozambique rice is predominately sold in open bags and if rice price does not reflect its quality, then inefficiencies may lead to consumer welfare losses. Importantly, it is possible that impoverished communities are priced out of the market due to inflated and inefficient prices. The objective of this study is to examine determinates of rice price by estimating the impact of selected rice quality attributes on rice prices in DRC, Ghana …

Sensitivity And Threshold Dynamics Of Pinus Strobus And Quercus Spp. In Response To Experimental And Naturally-Occurring Severe Droughts, Heidi Asbjornsen, Cameron D. Mcintire, Matthew A. Vadeboncoeur, Katie A. Jennings, Adam P. Coble, Z. Carter Berry

All Materials

Increased drought frequency and severity are a pervasive global threat, yet the capacity of mesic temperate forests to maintain resilience in response to drought remains poorly understood. We deployed a throughfall removal experiment to simulate a once in a century drought in New Hampshire, USA, which coupled with the region-wide 2016 drought, intensified moisture stress beyond that experienced in the lifetimes of our study trees. To assess the sensitivity and threshold dynamics of two dominant northeastern tree genera (Quercus and Pinus), we monitored sap flux density (Js), leaf water potential and gas exchange, growth, and intrinsic water use efficiency (iWUE) …

Mechanisms Of Overyielding And Coexistence In Diverse Tallgrass Prairie Communities, Leslie E. Forero

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants compete for the same basic nutrient and water resources. According to the competitive exclusion principle, when a substantial overlap in resource pools exists, the best competitor for resources should drive all other species to extinction. The ability for plants to coexist in violation of the competitive exclusion principle is the “biodiversity paradox”. Coexistence is actually beneficial for plants: as species diversity increases, you typically see increases in plant biomass production (known as the biodiversity-productivity relationship). The mechanisms behind coexistence and the biodiversity-productivity relationship remain an ecological mystery. One hypothesis is that plants obtain water and nutrients from different places …

Observing Changes In Vegetable Production Through Alternative Agricultural Practices, Austin Grey Livingston

Graduate Theses/Dissertations

Locally, responsibly grown produce is becoming more popular as consumers are shifting to organic products or those obtained at a local farmer’s market. The importance of soil health through conservation practices is increasing as the negative effects of industrial production are apparent. The over-application of synthetic fertilizers, soil erosion from wind and water, and nutrient leaching in high vegetable production areas has initiated a need for the investigation of alternative management practices. The main objective of this study is to evaluate the effects of tillage and cover crops in the production of green beans and okra. In 2019 and 2020, …

Factors Affecting Irrigation Water Use In Southwest Missouri And Soil Microbial Response To Irrigation And Crop Residue, Shirley M. Dobbs

Graduate Theses/Dissertations

Sustainable use of water resources in Southwest Missouri requires a better understanding of factors that influence groundwater use by crop producers. The objective of this study was to assess the influence of weather patterns and edaphic factors on water used for agricultural irrigation. Groundwater withdrawal data from 14 high-use agricultural irrigation wells were monitored between 2009 and 2016 as part of the Southwest Missouri Irrigation Project. Stepwise and linear regression was used to assess the relationship of weather and edaphic factors in response to annual water use from each well. Precipitation volume, number of precipitation events, average maximum and minimum …

Pando's Lessons: Restoration Of A Giant Aspen Clone, Paul C. Rogers, Jody Gale, Darren Mcavoy

Aspen Bibliography

A 106 acre (43 ha) aspen clone lives in the Fishlake National Forest in south-central Utah. Clones are comprised of multiple aspen stems, called ramets, which are genetically identical. This particular colony of ramets was named “Pando” (Latin for “I spread”) by researchers believing it to be the largest living organism by mass on earth. Recently, forest managers have noted a rapid dying of mature stems without recruitment of younger trees. This unsustainable situation has galvanized restoration efforts at Pando. Human interventions caused this imbalance; restoration will rely on protection, monitoring, and innovation. As a laboratory, this forest icon may …

Baseline Sensitivity To Dmi Fungicides In Cercospora Spp. And Corynespora Spp. In Arkansas Soybeans, Evan Buckner

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Cercospora spp. and Corynespora spp. are two common foliar fungal pathogens in Arkansas amongst other soybean producing areas. Two primary diseases caused by Cercospora spp. are Cercospora Leaf Blight (CLB, caused mainly by C. kikuchii) and Frogeye Leaf Spot (C. sojina). Both diseases affect foliage, and when lesions collapse, leaves may fall prematurely resulting in yield loss. In the specific case of CLB, this is a disease on the rise since 2000, and also causes seed infection reducing seed quality. Target spot is a disease caused by Corynespora cassiicola, and is of less damaging for farmers in larger …

Resistance Screening And Association Mapping For Resistance To The Downy Mildew Pathogen Of Spinach, Dotun Olaoye

Graduate Theses and Dissertations

Spinach is an important cool leafy vegetable cultivated around the world, with large scale production in California and Arizona in the U.S. Spinach is a highly nutritious vegetable beneficial in the human diet. Spinach is affected by a number of biotic stressors. Downy mildew, caused by the oomycete pathogen Peronospora effusa, is a major threat to spinach as it affects the leaf quality and impacts the economic value of spinach. Several efforts have led to the development of resistant genotypes/cultivars to this pathogen. However, few studies have examined the genetics of resistance to the downy mildew pathogen in detail. This …

Does Integrating Crops With Livestock Production Impact Soil Properties And Crop Production?, Lindsey Anderson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Re-integrating crop and livestock production through cover crop (CC) and corn residue grazing could efficiently utilize resources and ensure profitability while improving environmental quality, but how this integration affects soils and crops is not well understood. We conducted two studies to address this. In the first study, we evaluated the impact of cattle (1.3-3.7 head ha^-1) grazing an oat (Avena sativa L.) CC on soil and crop yields in two adjacent irrigated no-till corn (Zea mays L.)-soybean (Glycine max L.) fields on silt loam soils in eastern Nebraska. Field I was grazed twice, while Field …

Effects Of Am Fungi From Conventional And No-Till Michigan Crop Fields On Plant And Soil Health, Derek Bennett

Masters Theses

Centuries of conventional till (CT) management in agriculture has depleted soil organic matter (SOM) by over 50%. While only comprising 5% in most soils, SOM provides soil with fertility and productivity. To compensate for SOM depletion, producers have been forced to increase their reliance on fertilizer and irrigation to maintain yields. In the coming decades, climate change is expected to challenge food production and threaten an already fragile system. With no remaining land left to cultivate, conservation management strategies such as no-till (NT) look to restore SOM and increase the resilience of food production for an ever growing, increasingly food …

Production, Evaluation, And Selection Of Elite Quality Protein Popcorn (Qpp) Hybrids, Leandra Marshall Parsons

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

In 2017, twelve Quality Protein Popcorn (QPP) inbred lines were developed and selected as premier dent by popcorn crosses fit for hybridization and testing. These QPP inbred lines were derived from specific Quality Protein dent Maize (QPM) by ConAgra Brands® popcorn line crosses to produce high lysine, vitreous popcorn lines capable of near-equal popping characteristics compared to the original popcorn parents. The QPP hybridization project commenced in the summer of 2018 utilizing these 12 inbred QPP lines and crossing them in a full diallel. Since then, the production of QPP hybrids has employed a diverse set of selection factors evaluating …

The Effect Of Anionic Surfactants On Herbicide Mixtures And Solutions, Ely Daniel Anderson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Herbicide mixtures are popular for farmers to delay the evolution of herbicide-resistant biotypes from occurring and control existing herbicide-resistant weeds. Glufosinate is a contact herbicide that has been observed as a mixture partner with many herbicides. In many cases, antagonistic interactions have occurred when using glufosinate in mixture with other herbicides. The antagonistic interactions have resulted in applications with incomplete weed control. Adjuvants have been known to impact an herbicide application by increasing herbicide penetration, spreadability, and efficacy. Adjuvants added to glufosinate mixtures can impact spray applications and increase weed control. The objectives of this research were: (1) investigate the …

Estimating Irrigation In Rice Fields With A Water Balance Approach, Kristen Trinh

Biological and Agricultural Engineering Undergraduate Honors Theses

Global food production must increase to meet the demand associated with increased population growth, so irrigation water use will continue to rise. Therefore, it is important to monitor water usage particularly when an irrigation flowmeter is unavailable. A field water balance was created for a selection of rice fields in East-central Arkansas under observation in 2018 and 2019. From those, irrigation inputs are deduced from the water balance alone. First, each field had sensors that collected water table level (WTL) data. Next, other water inputs and outputs such as precipitation and evapotranspiration (ET) were collected from two modeled sources. The …

Light Intensity Control For Plc-Based Hydroponic Demonstration System, Christian Hitt

Biological and Agricultural Engineering Undergraduate Honors Theses

In order to demonstrate a skill set obtained through the University of Arkansas Biological Engineering, a group of students and I developed a hydroponic system where plants could be grown in a chamber. System parameters such as air quality, irrigation, and lighting were controlled by a Programmable Logic Computer (PLC) and an array of sensors and actuators. Each student focused on a certain aspect of this system, mine being the lighting. Developing this system involved researching the relationship between light intensity and plant growth, designing a system to suspend the lights above the growth chamber, and develop a system to …

An Analysis Of The Pollinators Of Echinacea Purpurea In Relation To Their Perceived Efficiency And Color Preferences, Carmen Black

Honors Theses

This study aimed to better understand how insects interacted with species of Echinacea in Tennessee and specifically their preference to floral color. Based on previous studies I expected the main visitors to be composed of various bees, beetles and butterflies. Based on previous studies, I hypothesized that most bees (especially social bees) would most likely pollinate the purple/violet morphs of the flower versus the white morph. I also expected the bees would have the most visits to the coneflowers versus any other taxonomic group. I believe bees to be the majority of pollinators based upon the results of Stucky, Gadd, …

Examining The Invasion Of A Bush Honeysuckle Using Climate Analysis, Andrew Palmer

Biological Sciences Undergraduate Honors Theses

Within the study of invasive plants, particular importance is placed on elucidating the mechanisms by which these plants proliferate and dominate within their introduced ranges. Several theories have been advanced to explain these invasions, each with different implications for the predicted range of invasive plants. Recent studies have provided support for the application of several invasion theories to Lonicera maackii, or what is more commonly referred to as bush honeysuckle. This species provides a unique opportunity to examine the efficacy of these theories in explaining the range expansion of invasive plants. L. maackii is endemic to eastern Asia, but …

Winners And Losers In Reforestation Efforts In The Lower Rio Grande Valley Of Texas, And The Predictive Power Of Xylem Anatomy On Long-Term Growth And Survival, Clifton F. Albrecht

Theses and Dissertations

Reforestation has been ongoing in the Lower Rio Grande Valley annually since the 1980s, and to date over 6400 ha of land has been reforested in this area. However, there has been little subsequent study of the change and development of those forests as they mature. This thesis consists of two, interrelated, studies: (1) surveys of a five-site chronosequence of restored forests and (2) quantification of xylem anatomical traits of a subset of species present at the reforestation sites. Surveys showed a consistent reduction in species diversity and stem number density on the landscape, and identified a suite of species …

Understanding The Ecological Role, Population Dynamics, And Geographic Distribution Of Manihot Walkerae, Gisel Garza

Theses and Dissertations

Walker’s Manihot, Manihot walkerae Croizat (Euphorbiaceae), is an endangered plant that is endemic to the Tamaulipan thornscrub ecoregion. Understanding M. walkerae’s geographic distribution, populations, and species interactions can provide essential information for the development of sound conservation strategies. To this aim, I asked the following questions: 1) What is the potential geographic distribution for M. walkerae? and, will it be affected by climate change? 2) Using global and regional extinction risk assessments, what is the extinction risk category for M. walkerae after incorporating species distribution models? 3) What do natural history observations reveal about M. walkerae’s population …

Physical And Chemical Defense Mechanisms In Aloe Barbadensis Against Insect Herbivores, Zachary Johnson

Theses and Dissertations

Chapter 1: This chapter provides an overview of insect herbivore impacts on plants and plant defense mechanisms to combat them. I particularly focused on physical and chemical defenses in the broader sense.

Chapter 2: This chapter describes the experiments that showed the effects of extracts from Aloe barbadensis on the growth and development of tobacco hornworm (Manduca sexta) and fall armyworm (Spodoptera frugiperda), model herbivores used to understand herbivore growth and plant defenses. This study shows that extracts from the Aloe differentially affected the growth and development of M. sexta and S. frugiperda. This chapter …