Life Sciences Commons^™

Spatial Patterns Of Range Management And Fodder Resources: How Important Is Local Reserve Biomass?, Anja Linstädter, J. Eisold, Gisela Baumann

IGC Proceedings (1997-2023)

No abstract provided.

Fruit Tree Responses To Water Stress: Automated Physiological Measurements And Rootstock Responses, William D. Wheeler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

New orchard plantings utilize trees grafted to dwarfing rootstocks planted close together to facilitate larger harvests. These dwarfing rootstocks have not been comprehensively studied for their ability to withstand drought. This is of special importance in the Intermountain West which has limited rainfall. Additionally, orchard growers face competition for water from a growing population and increased uncertainty in rainfall from climate change. My research examined the use of dendrometers, which measure changes in trunk diameter, and sap flow sensors, which measure how quickly sap moves, as methods to inform growers about tree water status. I also used a weighing lysimeter …

Molecular Genetic Analysis Of Drought Resistance And Productivity Traits Of Rice Genotypes, Yheni Dwiningsih

Graduate Theses and Dissertations

Rice (Oryza sativa L.) is the staple food for a majority of the world’s population, and uses 30% of the global fresh water during its life cycle. Drought at the reproductive stage is the most important abiotic stress factor limiting grain yield. The United States is the third largest exporter of rice, and Arkansas is the top rice-producing state. The Arkansas rice-growing region in the Lower Mississippi belt is among the 10 areas with the highest risk of water scarcity. Adapted U.S. rice cultivars were screened for drought resistant (DR) traits to find sources for breeding U.S. rice cultivars for …

Application Of Forage Monitoring Technology To Track Drought Occurrences: Experiences From Eastern Africa, R. Kaitho, J. Ndung'u, G. Kariuki, M. Kingamkono, J. Gutta, E. Kebebe, P. Dyke

IGC Proceedings (1997-2023)

No abstract provided.

Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes

Biology ETDs

Few studies have examined inoculum potential of ectomycorrhizal fungi (EMF) in the absence of plant hosts, yet persistence of these fungi may be paramount to resilience of Pinus edulis and other mycorrhizal plant species. We conducted a study in which seven sites were selected in northwestern New Mexico with known dates of P. edulis extirpation and a lack of regeneration. Age classes included: two sites extirpated 10-20 years ago, two extirpated 55-65 years ago, two extirpated 500+ years ago, and one extirpated 11,000+ years ago. At each site, two plots were paired: an extirpated plot and the nearest live adult …

Growth And Water Use Of Perennial Ryegrass And Tall Fescue Under Different Irrigation Treatments, R. J. Martin, Trevor L. Knight, R. N. Gillespie, M. U. Riddle, Tom J. Fraser

IGC Proceedings (1997-2023)

No abstract provided.

Gobi Forage: An Early Warning System For Livestock In The Gobi Region Of Mongolia, L. Bolor-Erdene, Jay Peter Angerer, Sean Granville-Ross, M. Urgamal, D. Narangarel, D. Tsogoo, Tim Stewart, Dennis Sheehy

IGC Proceedings (1997-2023)

No abstract provided.

Verification Of A Forage Simulation Model Used For A Livestock Early Warning System In The Gobi Region Of Mongolia, Jay Peter Angerer, L. Bolor‐Erdene, M. Urgamal, D. Tsogoo

IGC Proceedings (1997-2023)

No abstract provided.

Adaptive Genetic Potential And Plasticity Of Trait Variation In The Foundation Prairie Grass Andropogon Gerardii Across The Us Great Plains’ Climate Gradient: Implications For Climate Change And Restoration, Matthew Galliart, Sofia Sabates, Hannah Tetreault, Angel Delacruz, Johnny Bryant, Jake Alsdurf, Mary Knapp, Nora M. Bello, Sara G. Baer, Brian R. Maricle Ph.D., David J. Gibson, Jesse Poland, Paul St Amand, Natalie Unruh, Olivia Parrish, Loretta Johnson

Biological Sciences Faculty Publications

Plant response to climate depends on a species’ adaptive potential. To address this, we used reciprocal gardens to detect genetic and environmental plasticity effects on phenotypic variation and combined with genetic analyses. Four reciprocal garden sites were planted with three regional ecotypes of Andropogon gerardii, a dominant Great Plains prairie grass, using dry, mesic, and wet ecotypes originating from western KS to Illinois that span 500–1,200 mm rainfall/year. We aimed to answer: (a) What is the relative role of genetic constraints and phenotypic plasticity in controlling phenotypes? (b) When planted in the homesite, is there a trait syndrome for each …

Drought- Conditioning Of Quaking Aspen (Populus Tremuloides Michx.) Seedlings During Nursery Production Modifies Seedling Anatomy And Physiology, Joshua L. Sloan, Owen T. Burney, Jeremiah R. Pinto

Aspen Bibliography

In the western US, quaking aspen (Populus tremuloides Michx.) regenerates primarily by root suckers after disturbances such as low to moderate severity fires. Planting aspen seedlings grown from seed may provide a mechanism to improve restoration success and genetic diversity on severely disturbed sites. However, few studies have examined the use of container-grown aspen seedlings for restoration purposes from both the outplanting and nursery production perspective. Thus, the purpose of this novel study was to examine how alterations in irrigation levels during nursery production across three seed sources would impact seedling performance attributes on harsh, dry outplanting sites. Irrigation …

Drought Decisions: Profit Maximizing Decisions During And After Drought Conditions, Robert Tigner, Elliott James Dennis

Extension Farm and Ranch Management News

In summary, using available price risk management tools can effectively reduce some of the market price risk variability that is inherent in agricultural production that are caused by either production or price risk.

Characterization Of Shallow Subsurface Hydrology In Large Fine-Grained Floodplains, Mary Grace Lemon

LSU Doctoral Dissertations

Floodplains are hydrologically dynamic, receiving water from overbank events, hyporheic flows, local precipitation, and regional groundwater sources. These sources are variously important contributors to the heterogeneous floodplain water pool that includes matrix water in soil micropores, mobile water in soil macropores, groundwater below the rooting zone, ephemeral to seasonal surface storage, and permanent surface water features such as oxbow lakes, sloughs, and other secondary channels. All sources may be ecologically relevant for floodplain vegetation, but the exact roles of each source in both controlling soil water and shallow groundwater recharge and in controlling floodplain water drainage are not well understood, …

Genetic Architecture Of Salt And Drought Tolerance In Cowpea, Waltram Second Ravelombola

Graduate Theses and Dissertations

Cowpea [Vigna unguiculata (L.) Walp.] is a diploid and nutrient-dense legume species. It provides affordable source of protein to human. Cowpea cultivation is prevalent in Africa, Asia, the western and southern U.S., and Central and South America. However, earlier reports have shown that drought and salt stress can be devastating to cowpea production. The objectives of this study were to screen for salt and drought tolerance in cowpea and to identify molecular markers associated with these traits. Simple methodologies to screen for drought (Chapter 2) and salt tolerance were developed (Chapter 3). Results suggested that: 1) a total of 14, …

Genetics Of Physiological Traits Associated With Drought Tolerance In Soybean (Glycine Max), Sumandeep Kaur Bazzer

Graduate Theses and Dissertations

Soybean (Glycine max L.) is one of the major row crops in the United States, and its production is often limited by drought stress. Physiological traits from exotic germplasm that confer drought tolerance may be useful in improving commercial soybean production. For example, carbon isotope ratio (δ13C) is positively correlated with water use efficiency (WUE), and nitrogen isotope ratio (δ15N) is negatively correlated with N2 fixation; canopy temperature (CT) is an indicator for genetic variation in transpiration and stomatal conductance. Therefore, the objectives of this research were to identify the genomic regions associated with: (1) δ13C and δ15N using a …

Diachronic Analysis Of Vegetation In The Sylvopastoral Zone (Senegal): What Lesson To Learn From?, A. T. Diop, A. Diouf, A. Wane

IGC Proceedings (1997-2023)

No abstract provided.

Compensatory Recruitment, Dynamic Habitat, And Selective Gear Present Challenges To Large-Scale Invasive Species Control, Timothy E. Walsworth, Kevin Landom, Jereme Gaeta

Ecology Center Publications

Control of long‐established invasive species to aid threatened native species presents major logistic and economic challenges. Invasive common carp (Cyprinus carpio ) recently accounted for over 90% of the fish biomass in Utah Lake (Utah, USA), driving many undesired changes to ecosystem structure. Carp control efforts have removed >12,000 tons of carp from the system over 10 yr. However, the impact of recent removal efforts on carp population structure and dynamics remains unclear. We develop an integrated age‐structured population model incorporating carp harvest data with independent standardized monitoring data to evaluate population‐level consequences of the removal effort and evaluate …

Characterization Of Squamosa Promoter Binding Protein Like (Spl), And Its Role In Drought Stress Tolerance In Medicago Sativa (Alfalfa)., Alexandria K. Hanly

Electronic Thesis and Dissertation Repository

Traditional breeding involving Medicago sativa (alfalfa), has resulted in minimal yield increases. Moreover, extreme environmental conditions threaten to further limit production. Strategies that make use of molecular tools – such as small non-coding RNA, miR156 – represent an innovative means by which to influence tolerance to abiotic stress. miR156 functions, at least in part, through the SQUAMOSA PROMOTER BINDING PROTEIN LIKE (SPL) family of transcription factors. In this study, the role of SPL9 in regulating alfalfa development and drought tolerance is evaluated. Examination of alfalfa plants with RNAi-mediated SPL9 (SPL9-RNAi) showed that plant height, stem thickness, and internode …

The Study Of Salinity And Drought Stress Effects On Three Range Species Agropyron Intermedium, Avena Barbata And Panicum Antidotale From Iran, M. M. Sharifi Kashan, Z. Tolui

IGC Proceedings (1997-2023)

No abstract provided.

Leaf Traits And Performance Vary With Plant Age And Water Availability In Artemisia Californica, Jennifer L. Funk, Julie E. Larson, Gregory Vose

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background and aims
Leaf functional traits are strongly tied to growth strategies and ecological processes across species, but few efforts have linked intraspecific trait variation to performance across ontogenetic and environmental gradients. Plants are believed to shift towards more resource-conservative traits in stressful environments and as they age. However, uncertainty in how intraspecific trait variation aligns with plant age and performance in the context of environmental variation may limit our ability to use traits to infer ecological processes at larger scales.

Methods
We measured leaf physiological and morphological traits, canopy volume, and flowering effort for Artemisia californica (California sagebrush), a …

Effects Of 10 Years Of Fire And Climate Variability On Perennial Grass Cover In Shortgrass Steppe, P. L. Ford

IGC Proceedings (1997-2023)

No abstract provided.

Gross Biomass And Root/Shoot Ratio Mediated Drought Sensitivities Of Ecosystem Carbon Exchange In A Meadow Steppe, Yunbo Wang, Wei Sun, Deli Wang

IGC Proceedings (1997-2023)

According to IPCC’s Report (2007), global precipitation regimes will change largely in the future, with more annual precipitation at the mid-latitude regions. Simultaneously, due to the accelerating industrialization and use of nitrogen (N) fertilizer, significant increase in nitrogen deposition has been widely documented (Liu et al., 2013).

Water and nitrogen are the two most important limiting factors for the ecological processes of arid and semi-arid grassland ecosystems; therefore, altered precipitation regimes and enhanced nitrogen deposition are likely to change vegetation composition, ecosystem productivity, and aboveground vs belowground biomass distribution.

In addition to these long-term changes, short-term climate extremes, such …

Drought Effect On Yield Of Forages Grass Species, Michal Kvasnovský, Pavel Knot, Lucia Hodulíková, Iva Klusoňová

IGC Proceedings (1997-2023)

Climate change (rising temperatures, lengthening of the growing season, increasing evaporation) significantly affects agricultural production in traditional production areas of Central Europe, as illustrated by example better results in growing of corn on its northern or upper height limit. Changes in the amounts and timing of rainfall events will probably affect ecosystem processes, including those that control carbon (C) cycling and storage. In relation to the ongoing global warming, it is desirable to test resistance of grass species to a lack of moisture. Seasonal variation in precipitation and temperature are important controls of soil and plant processes in grasslands. (Fiala …

Drought Tolerance Screening Of Avena Species By Inducing Water Stress Conditions At Vegetative And Flowering Stage, Harish C. Pandey

IGC Proceedings (1997-2023)

Oats is the most important cereal fodder crop grown in the winter season in the north western, central India and now extending to the eastern region. In India it is grown in Punjab, Haryana, Jammu & Kashmir, Himachal Pradesh, Uttar Pradesh, Madhya Pradesh, Rajasthan, Maharashtra and Bengal. Oat is a high yielding crop and the average yield varies from 45-55 ton of green fodder per hectare. Oat is ranked sixth in world cereal production statistics following wheat, maize, rice, barley and sorghum. Mostly oats are grown as green fodder and grain to be used as a feed for cattle. Since …

Elucidating The Molecular Pathways Involved In The Fitness And Water Stress Response Of Pseudomonas Synxantha 2-79 In The Plant Rhizosphere, Clint Henry D. Pablo

Master's Theses

Pseudomonas synxantha 2-79 is a biocontrol agent that represents beneficial indigenous rhizobacteria that are broadly distributed in the Pacific Northwest, USA and flourish in the rhizosphere of commercially grown wheat under surprisingly arid conditions. The molecular adaptation of 2-79-like bacteria to plants growing in dry soils is poorly understood. We hypothesized that the ability of 2-79 to colonize and persist in the rhizosphere of water-stressed plants is underpinned by the formation of hydrating biofilms and the utilization of root exudates that contain plant-derived osmoprotectants called quaternary ammonium compounds (QACs). We tested this hypothesis by identifying waters stress response pathways in …

California Drought Projections Based On Climate Change Models’ Effects On Water Availability, Lauren Lynam

Student Scholar Symposium Abstracts and Posters

Future streamflow in California, as predicted by eight climate projections models, and their effects on water availability are discussed in this paper. The unimpaired projected streamflow for eleven California rivers, collected from Cal-Adapt Streamflow are compared with their unimpaired historical flows (1950-2015) using eight climate model projections (2020-2099) developed by Scripps Institution of Oceanography’s Routed Streamflow Projections; Warm Dry RCP 4.5, Average RCP 4.5, Cool Wet RCP 4.5, Other RCP 4.5, Warm Dry RCP 8.5, Average RCP 8.5, Cool Wet RCP 8.5, Other RCP 8.5. Projected drought quantities, durations, and intensities are statistically tested against historical values to determine significance …

Aboveground-Belowground Interactions: Roles Of Soil Biotic And Abiotic Factors On Switchgrass's (Panicum Virgatum) Growth, Defense Against Herbivory And Cell Wall Chemistry., Binod Basyal

Electronic Theses and Dissertations

Plants constantly interact with their biotic and abiotic soil environments. Most terrestrial plants form beneficial associations with soil microbes such as arbuscular mycorrhizal (AM) fungi, which are widely known for their ability to transfer soil phosphorus and nitrogen to the host plants. They help plants tolerate drought stress and improve plant defense against herbivores such as plant-parasitic nematodes (PPNs). This dissertation investigates the role of AM fungi on switchgrass’s (Panicum virgatum) growth, cell wall chemistry, and defense against PPNs using a combination of growth chamber and field studies. Switchgrass is a native warm-season species which is gaining traction as candidate …

Landscape-Scale Patterns Of Fire And Drought On The High Plains, Usa, Paulette L. Ford, Charles Jackson, Matthew Reeves, Benjamin Bird, David Turner

IGC Proceedings (1997-2023)

We examine 31 years (1982-2012) of temperature, precipitation and natural wildfire occurrence data for Federal and Tribal lands to determine landscape-scale patterns of drought and fire on the southern and central High Plains of the western United States. The High Plains states of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas and Wyoming have been in the midst of ongoing extreme drought, experiencing below normal precipitation and above normal temperatures for the past several years. Climate change is predicted to have multiple effects on fire regimes. Longer periods of drought conditions, coupled with hot, dry and windy weather, provide …

Economics Of Bn Hybrid Grass Production Bundelkhand Region Of India: A Case Study, Satendra Kumar, Ravi Pratap Singh, Rajiv K. Agrawal, J. B. Singh, M. M. Das, Sunil Kumar

IGC Proceedings (1997-2023)

Napier grass is also called as Elephant Grass due to its tallness and vigorous vegetative growth. The plants tiller freely and a single clump may produce more than 60 tillers under favorable climatic and soil conditions. Unfortunately, the grass coarse-textured, the leaf blade sheaths as well as sharply serrated, leaf margins. Therefore, cross was made between Bajra which is more succulent, leafy, fine-textured, palatable, fast growing and drought resistant and Napier to combine these qualities with its high yielding potential. The outcome Hybrid Napier is a perennial grass which can be retained on field for 2-3 years. Hybrid napier grass …

Landscape Performance Of Buck Roses Under Minimal-Input Conditions In North-Central Texas, Derald A. Harp, Gaye Hammond, David C. Zlesak, Greg Church, Mark Chamblee, Steve George

Faculty Publications

Griffith Buck (Iowa State University) bred roses (Rosa sp.) to survive long, cold winters and hot, humid summers yet still retain their foliage without fungicides. Unfortunately, there is little known about the performance of Buck roses in the southern United States. Thirty-eight Buck rose cultivars were evaluated for flowering, disease resistance, drought tolerance, and overall landscape performance in alkaline soils with no fertilizer, no pesticides, and only limited irrigation. Flowering occurred on a bimodal basis, with the highest per plant mean bloom number (16.3 blooms) and bloom coverage (9.7%) in April, and a second flowering in the fall, with …

Influence Of Forest-To-Silvopasture Conversion And Drought On Components Of Evapotranspiration, Adam P. Coble, Alexandra R. Contosta, Richard G. Smith, Nathan W. Siegert, Matthew A. Vadeboncoeur, Katie A. Jennings, Anthony J. Stewart, Heidi Asbjornsen

Natural Resources & the Environment

The northeastern U.S. is projected to experience more frequent short-term (1-2 month) droughts interspersed among larger precipitation events. Agroforestry practices such as silvopasture may mitigate these impacts of climate change while maintaining economic benefits of both agricultural and forestry practices. This study evaluated the effects of forest-to-silvopasture (i.e., 50% thinning) conversion on the components of evapotranspiration (transpiration, rainfall interception, and soil evaporation) during the growing season of 2016. The study coincided with a late-summer drought throughout the northeastern U.S., which allowed us to also evaluate the effects of forest-to-silvopasture conversion on drought responses of multiple tree species, including Pinus strobus, …