Agronomy and Crop Sciences Commons^™

Milling And Functional Properties Of Co-Mingled Rice Cultivars, Nikhil N. Basutkar

Graduate Theses and Dissertations

Differences have been observed in the milling and functional properties of different rice cultivars, particularly between hybrid and pureline cultivars. Co-mingling of rice cultivars commonly occurs during harvest, storage and drying operations. Thus, there is a need to study the effect of co-mingling on the milling and functional properties of rice cultivars. Two long-grain, hybrid (H) cultivars CL XL745 and CL XL729 and two long-grain, pureline (P) cultivars CL 151 and Wells were used to prepare CL XL745/CL 151 (H/P), CL XL745/CL XL729 (H/H) and Wells/CL 151 (P/P) co-mingles, mixed in various proportions. Milled rice yield (MRY), head rice yield …

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, …

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. …

B.R. Wells Rice Research Studies 2012, R. J. Norman, K.A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Automated Conserved Non-Coding Sequence (Cns) Discovery Reveals Differences In Gene Content And Promoter Evolution Among Grasses, Gina Marie Turco, James C. Schnable, Brent S. Pedersen, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

Conserved non-coding sequences (CNS) are islands of non-coding sequence that, like protein coding exons, show less divergence in sequence between related species than functionless DNA. Several CNSs have been demonstrated experimentally to function as cis-regulatory regions. However, the specific functions of most CNSs remain unknown. Previous searches for CNS in plants have either anchored on exons and only identified nearby sequences or required years of painstaking manual annotation. Here we present an open source tool that can accurately identify CNSs between any two related species with sequenced genomes, including both those immediately adjacent to exons and distal sequences separated by …

Textural And Sensory Qualities Of Muffins Prepared With Fermented Rice Bran, Breeanna Williams, Navam Hettiarachchy, Srinivas J. Rayaprolu

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Rice is one of the most popular cereal grains in the world. Rice bran, a by-product of the rice milling process, contains an abundance of nutrients including protein, fiber, vitamin B complex, vitamin E, and other nutraceuticals. However, rice bran is underutilized in the food industry. In this project muffins were prepared with varying concentrations (2.5%, 5.0%, 7.5%, 10.0%, 15.0%, 20.0%, and 25.0%) of 60 mesh (250 µm) fermented rice bran (60 mFRB) and 80 mesh (180 µm) fermented rice bran (80 mFRB). A cappuccino muffin formulation was used as flavor for all the samples. The control sample was prepared …

Estimating Crop Yield Potential At Regional To National Scales, Justin Van Wart, Kurt Christian Kersebaum, Shaobing Peng, Maribeth Milner, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

World population will increase 35% by 2050, which may require doubling crop yields on existing farm land to minimize expansion of agriculture into remaining rainforests, wetlands, and grasslands. Whether this is possible depends on closing the gap between yield potential (Yp, yield without pest, disease, nutrient or water stresses, or Yw under water-limited rainfed conditions) and current average farm yields in both developed and developing countries. Quantifying the yield gap is therefore essential to inform policies and prioritize research to achieve food security without environmental degradation. Previous attempts to estimate Yp and Yw at a global level have been too …

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 …

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. …

Documentation And Control Of Acetolactate Synthase-Resistant Barnyardgrass (Echinochloa Crus-Galli) In Arkansas Rice, Michael Joshua Wilson

Graduate Theses and Dissertations

Barnyardgrass, the most problematic grass weed of Arkansas rice, was found resistant to propanil in 1990, and since then, it has evolved resistance to quinclorac and clomazone. Barnyardgrass is now believed to have evolved resistance to acetolactate synthase (ALS)-inhibiting herbicides. The goal of this research was to confirm and determine the level of resistance of the putative resistant biotype to the ALS-inhibiting herbicides imazethapyr, bispyribac, and penoxsulam and to develop herbicide programs for controlling ALS-, propanil-, quinclorac-, and clomazone-resistant barnyardgrass. The lethal dose needed to kill 50% of the putative ALS-resistant plants was higher than that of the susceptible biotype …

B.R. Wells Rice Research Studies 2011, R. J. Norman, K.A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

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 …

Milling Characteristics Of High And Low Quality Rice, Alexandria Huck, Sarah Lanning, Terry Siebenmorgen

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Harvest moisture contents (HMCs) have been proven to play a role in rice quality, especially affecting head rice yield (HRY) due to fissuring or immature kernels. Differences in milling characteristics between samples having high and low level milling quality were studied in this experiment. Two hybrid, long-grain cultivars (CL XL729 and CL XL745) and two pureline, long-grain cultivars (CL 181 and Wells) were harvested at near optimal and low HMCs, representing high and low milling quality, respectively. Lots were dried to approximately 12.5 ± 0.5% and milled in triplicate for durations of 10, 20, 30, and 40 s. Results showed …

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 …

B. R. Wells Rice Research Studies 2010, R. J. Norman, K. A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

The 2010 Rice Research Verification Program ( RRVP) was conducted on twenty-two commercial rice fields across the state. Counties rarticirating in the program included Arkansas, Ashley, Chicot, Clark, Clay, Cross, Desha, Drew, Greene, Jackson, Jefferson, Lafayette, Lawrence, Lonoke, Mississippi, Phillips, Poinsett (2 fields), Prairie, Randolph, St. Francis, and White for a total of 1456 acres. Grain yield in the 2010 RRVP averaged 167 bu/acre ranging from 113 to 215 bu/acre. The 2010 RRVP average yield was 25 bu/acre greater than the estimated Arkansas state average of 142 bu/acre. The highest yielding field was in Clay County with a grain yield …

Antioxidant And Antihypertensive Activities Of Rice Bran Peptides, Janika Hull, Arvind Kannan, Navam S. Hettiarachchy

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Protein isolates and peptide fractions from food sources (cereal grains), have been shown to exert bioactive properties including antiobesity, anticancer, antiangiogenic, etc. One such food source is rice bran, which is an underutilized co-product of rough rice milling. It contains 90% of the nutrients and nutraceuticals of value to health, including high quality protein. The high quality protein is a potential source to generate peptides that can reduce hypertension and oxidative stress, both being important risk factors for cardiovascular diseases. The objective of this study was to extract peptide hydrolysates from heat stabilized defatted rice bran by enzymatic hydrolysis, evaluate …

Properties Of Gluten-Free Pasta Prepared From Rice And Different Starches, Alexandria W. Mertz, Ya-Jane Wang

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Rice is one of the few cereal products that does not contain gluten. However, the absence of gluten poses problems in the structure of and cooking quality of rice pasta. The objective of this project was to investigate the addition of starch on the physicochemical properties and cooking quality of rice-based pasta. Rice-based pasta was prepared from parboiled long-grain rice flour with the addition of 25% cooked starch from different sources. The color and pasting properties of the ground pasta flour were measured by a chroma meter and a Rapid Visco Analyser, respectively. The pasta was cooked to the optimum …

B. R. Wells Rice Research Studies 2009, R. J. Norman, K. A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

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 …

B. R. Wells Rice Research Studies 2008, R. J. Norman, J. F. Meullenet, K. A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

B.R. Wells Rice Research Studies 2007, R. J. Norman, J. F. Meullenet, K. A.K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

B.R. Wells Rice Research Studies 2006, R. J. Norman, J. F. Meullenet, K. A.K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Field Evaluation Of Herbicides On Rice 2005, Drew T. Ellis, Ronald E. Talbert, Marilyn R. Mcclelland

Arkansas Agricultural Experiment Station Research Series

Field studies to evaluate herbicides in rice weed management systems were conducted in 2005 at the Rice Research and Extension Center near Stuttgart, Arkansas. New herbicides, herbicide mixtures, and application timings were evaluated for weed control efficacy and rice tolerance. Results of these studies, in part, provide useful information to producers, fellow researchers, and the crop protection industry for the most effective, economical herbicide programs for successful rice production in Arkansas.

B.R. Wells Rice Research Studies 2004, R. J. Norman, J. F. Meullenet, K. A.K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Field Evaluation Of Herbicides On Rice 2004, Brian V. Ottis, Ronald E. Talbert, Andrew T. Ellis

Arkansas Agricultural Experiment Station Research Series

Herbicide evaluation studies on rice were conducted in 2004 at the Rice Research and Extension Center near Stuttgart, AR, in an effort to evaluate new herbicides, herbicide mixtures, and their application timings for weed control and crop tolerance. Results of these studies, in part, provide useful information to producers, fellow researchers, and the Crop Protection Industry for the potential use of new herbicide programs for successful rice production in Arkansas.

B. R. Wells Rice Research Studies 2003, R. J. Norman, J.-F. Meullenet, K. A.K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice-producing state in the U.S., representing just over 48% of the total U.S. production and 48.5% of the total acres planted to rice. Rice cultural practices vary across the state and across the U.S. However, due to changing political, environmental, and economic times, the practices are dynamic. This survey was initiated in 2002 to monitor how the changing times reflect the changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas where rice is produced. Questions included topics such as …

Field Evaluation Of Herbicides On Rice 2003, Ronald E. Talbert, Brian V. Ottis, Mayank S. Malik, Andrew T. Ellis

Arkansas Agricultural Experiment Station Research Series

Herbicide evaluation studies on rice were conducted in 2003 at the Rice Research and Extension Center near Stuttgart, Ark., in an effort to evaluate new herbicides, herbicide mixtures, and their application timings for weed control efficacy and crop tolerance. Results of these studies, in part, provide useful information to producers, fellow researchers, and the crop protection industry for the potential use of new herbicide programs for successful rice production in Arkansas.

B.R. Wells Rice Research Studies 2002, R. J. Norman, J.-F. Meullenet

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producing state in the U .S .. representing almost 46% of the total U .S. production and almost 47% of the total acres planted to rice . Rice cultural practices vary across the state and across the U.S. However, due to changing political, environmental, and economic times, the practices arc dynamic. This survey was initiated in 2002 to monitor how the changing times reflect the changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county Extension agents in each of the counties in Arkansas that produce rice. Questions …

Vietnam’S Rice Economy: Developments And Prospects, Kenneth B. Young, Eric J. Wailes, Gail L. Cramer, Nguyen Tri Khiem

AAES Research Reports and Research Bulletins

Vietnam shifted rapidly from being a net rice importer prior to 1987 to become the second largest world rice exporter by 1995. Net rice exports have leveled off at about 3.8 million metric tons from 1997 to 1999. The world rice price has dropped dramatically in 2000 to barely cover the rice production cost in Vietnam, and net rice exports are expected to fall to 3.4 million mt because of the poor import demand in 2000. This report reviews the policy adjustments that led to the rapid growth in rice production and evaluates the prospects for Vietnam to continue as …