Life Sciences Commons^™

Methane Emissions And Ammonia Volatilization From Drill-Seeded, Delayed-Flood Rice On A Silt-Loam Soil In Arkansas, Christopher Wade Rogers

Graduate Theses and Dissertations

The Environmental Protection Agency (EPA) currently uses a single methane (CH4) emissions factor of 160 kg CH4-C ha-1 for a primary rice (Oryza sativa L.) crop. The emissions factor is based on studies that do not adequately represent current management practices in Arkansas. Another concern is pre-flood fertilizer nitrogen (N) management, as the common N source, urea, is prone to loss via ammonia (NH3) volatilization. Thus, the objective of this research was to investigate trace gas emissions from rice on a silt-loam soil, including CH4 emissions as influenced by nitrogen (N) fertilization (i.e., optimal N and no N) in 2011, …

Effects Of Cerium Oxide Nanoparticles In Cereals: Insights Into The Toxicity Mechanisms And Macromolecular Modifications, Cyren Mendoza Rico

Open Access Theses & Dissertations

Despite the inundation of studies on the interaction of engineered nanomaterials (ENMs) with plants, investigations involving complete life cycle (i.e from seedling establishment to full maturity) are still lacking. Assessments on the nutritional value of plants cultivated to full maturity in ENMs-treated soil are also missing. Cerium oxide nanoparticles (nCeO2) have significant interactions with plants; however, there are no life cycle studies yet on their implications in cereals like rice (Oryza sativa L.), wheat (Triticum aestivum L.), and barley (Hordeum vulgare L.). These cereals are globally important crops that support the economic activity, and nutritional and health needs of billions …

Development Of A Loop-Mediated Isothermal Amplification For The Detection Of Burkholderia Glumae, Maria Alejandra Caldera

LSU Master's Theses

Bacterial panicle blight is among the three most limiting diseases of rice production in the United States. Yield loss up to 40% has been reported from rice fields severely infested with bacterial panicle blight. The disease is caused by Burkholderia glumae and B. gladioli. Although, both species produce similar symptoms and are closely related, but B. glumae strains are more aggressive and cause more severe symptoms on rice. Bacterial panicle bight is difficult to manage in the absence of effective chemical control measures. Rapid and early disease detection is needed to avoid severe yield losses. Several techniques have been developed …

The Effects Of Salinity On Pythium Disease Of Rice And Soybean, Terea Jeanette Stetina

Graduate Theses and Dissertations

Increasing salinity is an important factor limiting agricultural productivity worldwide. In addition to direct effects on growth and yield, diseases also may be affected. This study characterized the effects of soil salinity on seedling disease of soybean and rice caused by Pythium spp. Controlled environment experiments on soybean used two cultivars which differed in chloride tolerance and soil treated with a CaCl₂ solution to create a range of electrical conductivity (EC) levels. For soybean, soil was either not infested or infested with Pythium sylvaticum or P. aphanidermatum (pathogenic to soybean), or P. oligandrum (not pathogenic to soybean). Twenty-one days …

A Comparison Of Milled Rice Fissuring Kinetics Of Hybrid And Pureline Cultivars, Semehar Haile Tesfaye

Graduate Theses and Dissertations

Over the past decade, the use of hybrid rice cultivars has greatly increased, and this has led to questions about the processing behavior of hybrid cultivars. This study compares the milled rice fissuring kinetics of hybrid and pureline cultivars. Also, this study elucidates the effects of kernel type (long-grain vs. medium-grain rice cultivars), surface lipid content (SLC), and kernel thickness on fissuring rates.

Three hybrid (CL XL745, CL XL729 and XL753) and five pureline (Wells, CL151, Cheniere, Jupiter and CL261) cultivar lots were procured. Jupiter and CL261 are medium-grain cultivars, whereas the rest are long-grain cultivars. Two experiments were conducted. …

Spatial Distributions Of Rhizoctonia Species In Soybean Fields Undergoing Annual Rotations With Rice, Terry Neil Spurlock

Graduate Theses and Dissertations

Aerial blight is caused by Rhizoctonia solani AG1-IA. This pathogen also causes sheath blight of rice. In Arkansas, many soybean and rice fields undergo an annual rotation of these two crops which facilitates a continuous source of inoculum from one year to the next. Aerial blight is a two stage disease in that R. solani AG1-IA colonizes the plant during the early vegetative growth stages and then aerial blight develops after the soybean canopy closes in the later reproductive stages of development. As a result of the upper portion of the canopy often being asymptomatic, significant yield loss can occur …

The Role Of Oswrky71 And Its Interacting Proteins In Seed Germination And Early Growth Of Cereal Grains, Margaret Ja Shin

UNLV Theses, Dissertations, Professional Papers, and Capstones

During seed germination and early seedling growth, complex molecular and physiological events occur in rice (Oryza sativa) and other cereal grains. As the seed transitions to vegetative tissue, it responds to both favorable and unfavorable environmental conditions and is vulnerable to attack by predation and disease. Although seeds are relatively small and tender in size, extensive and sophisticated molecular networks enables the immobile seed to grow, survive and adapt in its environment. One of the networks I am interested in is in the crosstalk between the gibberellin (GA) and abscisic acid (ABA) signaling pathways. These pathways are interesting because they …

Predicting Complex Phenotype-Genotype Relationships In Grasses: A Systems Genetics Approach, Stephen Ficklin

All Dissertations

It is becoming increasingly urgent to identify and understand the mechanisms underlying complex traits. Expected increases in the human population coupled with climate change make this especially urgent for grasses in the Poaceae family because these serve as major staples of the human and livestock diets worldwide. In particular, Oryza sativa (rice), Triticum spp. (wheat), Zea mays (maize), and Saccharum spp. (sugarcane) are among the top agricultural commodities. Molecular marker tools such as linkage-based Quantitative Trait Loci (QTL) mapping, Genome-Wide Association Studies (GWAS), Multiple Marker Assisted Selection (MMAS), and Genome Selection (GS) techniques offer promise for understanding the mechanisms behind …

Development Of Integrated Pest Management For Sugarcane Borer, Diatraea Saccharalis In Rice, Jaspreet Kaur Sidhu

LSU Doctoral Dissertations

Rice is grown over an area of approximately 500,000 acres in Louisiana. The lepidopteran stem borer complex attacking rice in the southern U.S includes stalk borer Chilo plejadellus Zincken, sugarcane borer (SCB) Diatraea saccharalis (F.) and Mexican rice borer, Eoreuma loftini Dyar. With the increasing impact of stem borers in Louisiana, an urgent need exists to develop strategies for management. Currently, no IPM program is in place for stem borers in Louisiana rice and research has been initiated to develop an IPM program for these pests. The first objective of this research was focused on host plant resistance. For this …

False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen

Graduate Theses and Dissertations

False smut of rice, caused by Ustilaginoidea virens (Cooke) Takahashi (Teleomorph: Villosiclava virens), has become a common disease in most major rice growing regions throughout the world. Considerable confusion exists regarding the infection process and the disease cycle. Therefore, a clearer understanding of pathogenesis caused by Ustilaginoidea virens is critical for future efforts to develop genetic and chemical tools to manage false smut in Arkansas and other regions of the world. The overall goal of this research was to clarify the infection process underlying false smut, with emphasis on comparing and contrasting the histological basis of root and foliar infections. …

Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher

Graduate Theses and Dissertations

Rice (Oryza sativa L.)-based cropping systems are different from other row crops due to the flood-irrigation scheme used from about one month after planting to a few weeks prior to harvest. The frequent cycling between anaerobic (i.e., flooding during the growing season) and aerobic (i.e., generally, the remainder of the year) conditions can influence the rate of soil organic matter (SOM) decomposition, which can greatly influence carbon (C) and nitrogen (N) storage and sequestration in the soil over time. Therefore, a study was conducted on a silt-loam soil (fine, smectitic, thermic, Typic Albaqualf) at the Rice Research and Extension Center …

Single-Pass Drying Of Rough Rice Using Glass Transition Principles, George Owira Ondier

Graduate Theses and Dissertations

The objective of this research was to study the drying characteristics, milling quality, and functional properties of rough rice subjected to single-pass drying while controlling kernel material states. Drying experiments were conducted at 60, 70, and 80C and relative humidities ranging from 13 to 83%. High drying air relative humidities (greater than 63%) maintained both the kernel surface and core in a rubbery state during drying, whereas low drying air relative humidities caused rapid transitioning of the surface layers from a rubbery to a glassy state. Long-grain pureline cultivar, Wells, medium-grain pureline cultivar, Jupiter, and long-grain hybrid cultivar, CL XL729, …

The Potential Environmental Benefits Of Hybrid Rice Varieties, Haxhire Myrteza

Graduate Theses and Dissertations

With water insufficiency being already a major issue and potential carbon policies on greenhouse gas (GHG) emissions, Arkansas rice producers may need to undergo some changes in regards to rice cultivar selection. The purpose of this study is to estimate the environmental benefits of cultivating hybrid rice varieties as opposed to conventional and Clearfield rice varieties. To accomplish this goal, water use and GHG emissions were estimated on per acre (ac) and per bushel (bu) basis for most commonly cultivated rice varieties in Arkansas. The study focuses particularly on six main rice stations in the State of Arkansas. The hypothesis …

Multifunctionality In U.S. Rice Production: A Logit Analysis In Farmers Participation, Juan Tur Cardona

Graduate Theses and Dissertations

Multifunctional agriculture is particularly fundamental to some working lands conservation policies and programs, such as the Environmental Quality Incentive Program (EQIP), Conservation Security Program (CSP) and Wildlife Habitat Incentive Program (WHIP). Farmers can also be engaged in providing recreational and agri-tourism services such as hunting, fishing, bird-watching, farm tours, petting zoos and hospitality services. Using the Agricultural Resource Management Survey (ARMS) we analyze factors associated with participation in conservation, recreation and agri-tourism activities as a function of farm structure, farm financial measures, production practices, and socio-demographic characteristics of the farm operator. To estimate the functional relationships we estimate a binary …

Rice (Oryza Sativa) Response To Low Glyphosate Rates As Influenced By Cultivar, Growth Stage, And Imazethapyr Applications, Jason R. Meier

Graduate Theses and Dissertations

Off-target movement of glyphosate onto rice is a perennial concern when rice is grown in close proximity to glyphosate-tolernat crops. If differential tolerance to sub-lethal rates of glyphosate exists among rice (Oryza sativa) cultivars, these cultivars could be utilized in breeding programs or glyphosate-drift sensitive areas. Field and greenhouse experiments were conducted in 2006 and 2007 to examine differences among rice cultivars in response to sub-lethal rates of glyphosate, and to examine imidazolinone-tolerant rice response to imazethapyr and sub-lethal rates of glyphosate applied sequentially to determine the potential for either herbicide to predispose rice to greater injury. In the field …

Physiological, Biochemical And Molecular Characteristics Associated With Virulence Of Burkholderia Glumae: The Major Causative Agent Of Bacterial Panicle Blight Of Rice, Hari Sharan Karki

LSU Master's Theses

Burkholderia glumae is the bacterial pathogen causing bacterial panicle blight disease of rice (BPB). The pathogen, whose growth and pathogenicity is favored by high temperatures, has become a serious threat to rice production around the world possibly due to the current global climate changes. In this study, previously reported avirulent B. glumae strains were characterized in respect to the production of known virulence factors, toxoflavin, lipase and motility, and potential virulence factors, including polygalacturnase and type III secretion system (hypersensitive response). Considerable phenotypic variation was observed among the strains tested. Virulence of the B. glumae strains was closely related to …

Effect Of Water On Micronutrient Content And Yield In Rice (Oryza Sativa L.), Sheila Lorraine Baker

Master's Theses

Rice (Oryza sativa L.) is an important crop in many countries. According to the IRRI, more than 2 billion people globally depend on rice as a staple food (Dawe, et al. 2003). Studies on micronutrient content in rice and the effect of water in availability of the nutrients may aid in decreasing global nutrient deficiencies. Rice is grown under different water regimes such as AWD and intermittent flooding, sprinkler and furrow irrigation. A greenhouse pot experiment of rice utilizing a split plot design under different water regimes was conducted to assess the affect of water on (1) DTPA extractable soil …

Semi-Global Analysis Of The Early Cold Stress Response Transcriptome Of Developing Seedlings Of Rice (Oryzasativa L.,Japonica), Chen Cheng

Electronic Theses and Dissertations

Plants are either sensitive or insensitive to low temperatures. Cool-season species acclimate to chilling and develop tolerance to freezing. Warm-season species vary in the degree of sensitivity to chilling and are not capable of acclimation. Both freezing and chilling tolerance involve the activity of an intricately coordinated network of genes. The regulatory network that defines cold acclimation and freezing tolerance is well understood in Arabidopsis. The centerpiece of this network is a group of transcriptional activators that coordinate a battery of downstream defense-related genes. In contrast, little is known about the corresponding regulon in non-acclimating species. This study utilized …

Economic Evaluation Of Potential Changes In Farm Program Price Support For Typical Louisiana Rice And Cotton Farming Operations, Manuel E. Aldana

LSU Master's Theses

Increased government deficit has led the congress to reduce federal spending. Proposed budget cuts are intended to decrease government spending in several areas, including agriculture. Reductions in farm program spending could cause significant adverse effects on the financial situation of many farms, particularly to rice and cotton enterprises, due to their high reliance on farm program payments as a source of income. Representative rice and cotton operations of one, two, three, and four entities as single crop enterprises were considered and developed for use in this study. Farm enterprise sizes were determined by estimating the acreage level at which a …

Integration Of Management Tactics For The Rice Water Weevil Lissorhoptrus Oryzophilus Kuschel With Particular Emphasis On Use Of Plant Resistance (Tolerance), Li Zou

LSU Doctoral Dissertations

Studies were conducted to test the hypothesis, significant benefits can be achieved for the management of rice water weevil, Lissorhoptrus oryzophilus Kuschel, by the use of rice varieties with low levels of host plant resistance coupled with the judicious use of cultural practices and insecticides. Tolerant traits of a current commercial variety of rice, "Bengal", was manifested consistently over multiple years. Study on rice growth as effected by weevil injury showed that pruning of root systems by larvae of weevil resulted in a decrease in tiller number and shoot biomass of rice plants in the vegetative stage of growth. Yield …

An Evaluation Of Cost Of Production Insurance As An Income Support Tool For Rice And Cotton Producers In Louisiana, Erica Harding

LSU Master's Theses

Crop insurance has received a great deal of attention over the past several years. The main interest and focus of analysis on crop insurance has been to evaluate its use and performance as a risk management tool for agricultural producers. Several different types of crop insurance policies are currently available, ranging from minimal yield coverage to revenue coverage. Cost of production crop insurance has been proposed recently as a low cost, safety net type of insurance policy for agricultural producers. This study evaluated the performance of cost of production crop insurance for cotton and rice producers in Louisiana. Crop income …

Consumer Sensory Characteristics Of Butter Cake Made From Wheat And Rice Flours, Ashley Elizabeth Bond

LSU Master's Theses

Rice is an important commodity in Louisiana and throughout the world. During the milling process, about 15% of rice kernels become broken. Louisiana produced approximately 2,011,000 hundred weights of broken rice kernels in 2002. Converting broken rice into rice-based products adds dollars back to broken rice. The market potential for rice in processed foods is huge. In the refrigerated and frozen baked foods category, it is approximately $14.3 billion; while in the baked snack foods and wholesale bakery foods category, it is approximately $31.4 billion. Approximately 1-2% of the United States population suffers from Celiac Spruce Disease, which is a …

Studies On Rice Transformation And The Use Of Transformed Plants [Electronic Resource], Qiming Shao

LSU Doctoral Dissertations

This research was conducted to enhance utilization of the Liberty herbicide resistance transgene in rice. Non-lethal methods to determine the sensitivity of transgenic rice plants to hygromycin B and Liberty were developed, tested and used in this research. Four homozygous transformed plants were selected to make reciprocal crosses with their non-transformed parent cultivars Taipei 309 and Nipponbare. Their resistances to Liberty and hygromycin B were controlled by the closely linked single dominant genes bar and hpt. Some non-resistant phenotypes in the F2 populations were due to gene silencing. The bar gene in some of these plants were allelic and some …

Resistant Rice Starch Development, Siow Ying Tan

LSU Master's Theses

This study showed that enzyme treatments were effective in producing resistant starch from rice flour and starch. Rice starch produced higher resistant starch yields than rice flour. The lower resistant starch yields in rice flour could be attributed to the presence of lipids and proteins which were competitively binding to amylose, resulting in decreased recrystallization of amylose. The gelatinization type and incubation periods were not as influential as enzyme treatments in the resistant starch formation. The rapid visco amylograph (RVA) analysis indicated that the gelatinized samples have minimal pasting characteristics since they had been gelatinized prior to enzyme treatments. Pasting …

A Game Theoretic Analysis Of U.S. Rice Exports Under Alternative Japanese And South Korean Policy Scenarios, Dae-Seob Lee

LSU Doctoral Dissertations

As a result of the Uruguay Round (UR), the impact on the international rice market is profound. In addition, another round of the WTO trade negotiations has started and the impacts of potential policy changes on rice trade are unknown. The major U.S. benefit of the UR has been the access to the Japanese market. However, the U.S. share of this import market has been unstable and the share of Korean rice market is zero percent. Therefore, this study attempts to analyze the potential implication of U.S. rice exports to Japan and Korea. The Japanese and Korean rice economies as …

Economic Evaluation Of Alternative Rough Rice Marketing And Storage Strategies, April Street

LSU Master's Theses

The alternative rough rice marketing and storage strategies were evaluated using three methods of analysis. The methods used in this study were MOTAD, simulation, and stochastic dominance. Historical rough rice prices from 1980/81 - 2000/01 was used and tested for trends and seasonality in order for the methods to be formed properly. SAS was used to verify that the data used in this study did not follow any time trend or reflect seasonality. MOTAD, simulation, and stochastic dominance were used to determine the most efficient marketing and storage strategy that will enable rice farmers to make the best decisions and …

Investigation Of Different Patterns Of Induction Of Amylases In Different Cultivars Of Rice, Oryza Sativa L., Angela M. Mosley

Master's Theses

This study investigated whether rice exhibits exceptions to the accepted model, in cereals, for the induction of a and P-amylase in the embryo and endosperm during germination. We also tried to establish whether different patterns of induction were cultivar specific, or due to the influence of ripening temperature, or a component of the incubation medium. An isoelectric focusing technique was used to monitor a- and P-amylase activities, a spectrophotometric assay was used to quantify the activity of a-amylase, and two cDNA clones, RAmy3D and RAmylA, were used to measure a-amylase RNA accumulation by Northern analysis. Distinct patterns of induction of …

Biochemical Investigations Of Black Gram (Phaseolus Mungo L.) And Rice (Oryza Sativa L.) Proteins And Their Improved Nutritional Functionality In The Fermented Product—Idli, Vinodkumar W. Padhye

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this investigation have been to characterize black gram (Phaseolus mungo L.) and rice (Oryza sativa L.) proteins and to study changes in their nutritional value due to fermentation. Black gram, the legume chosen for this work, is one of the most important legume crops throughout a large part of the tropics.

The protein content of 60 mesh, dehydrated, defatted black gram meal was 28.5 percent. Sodium carbonate (0.5-1.0 percent), tetra-sodium pyrophosphate (0.5 percent), and sodium dodecyl sulfate (SDS) (0.5-5 percent) proved to be the potential protein solubilizers as they extracted more than 76 grams of …