Life Sciences Commons^™

B. R. Wells Arkansas Rice Research Studies 2022, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 50.1% of total U.S. rice production and 49.8% of the total acres planted to rice in 2022. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record 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 …

International Rice Outlook: International Rice Baseline Projections 2022-2032, A. Durand-Morat, S. Bairagi, W. Mulimbi

Research Reports and Research Bulletins

Rice prices in Asia increased since the Summer of 2022 mainly due to worries about a reduction in rice production in India caused by an abnormal monsoon season (Fig. 1). The upward trend in export prices solidified after India implemented a 20% export tariff on brown and milled long-grain rice, and a complete ban on exports of broken rice, in September 2022 to curve down exports and release the pressure on domestic rice prices. India’s rice export prices increased since then and proportionally to the value of the export tax. The latest estimates put rice production at 128 million metric …

Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye, Kristofor R. Brye, Diego Della Lunga

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

Wastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4∙6H2O), may provide a sustainable alternative to decreasing rock-phosphate reserves. Struvite can be generated via precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically and electrochemically precipitated struvite (CPST and ECST, respectively) on aboveground plant response in a hybrid rice cultivar grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)] using three replications of fertilizer treatment in a P-deficient silt loam (Typic Glossaqualfs). Aboveground …

Evaluation Of Biological And Chemical Seed Treatments For Management Of Rice Diseases, Sherif Adam Sharfadine

Graduate Theses and Dissertations

Rice is the primary staple for more than half of the global population and is the second most important cereal worldwide. In the US, rice is primarily grown in the southern states, with Arkansas leading production and responsible for 47% of the total rice production in the country. Diseases cause significant yield losses in rice. Sheath blight, rice blast and bacterial panicle blight are the main diseases in rice and cause significant yield losses. Sheath blight alone could cause up 50% yield loss in heavily damaged fields with highly susceptible cultivars. Additionally, rice seed and seedling diseases primarily caused by …

B.R. Wells Arkansas Rice Research Studies 2021, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 47.5% of total U.S. rice production and 47.8% of the total acres planted to rice in 2021. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record 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 …

International Rice Outlook: International Rice Baseline Projections 2021–2031, A. Durand-Morat, S. Bairagi

Research Reports and Research Bulletins

The war in Ukraine and the lingering effects of the COVID-19 pandemic are pushing input costs to record levels. Although rice prices have increased some in the last several months, production costs have increased more than proportionally, undermining rice profitability.

We project global rice production will surpass global rice consumption for most of the coming decade, with a small deficit developing by the end of the projected period.

The projected growth in production is almost exclusively due to productivity gains since the global rice area is projected to increase only marginally by 2029–2031.

The projected growth in global rice consumption …

Impact Of Planting Arrangement And Drill Row Spacing For Direct-Seeded, Delayed Flood Rice, Mary Jane Lytle

Graduate Theses and Dissertations

Direct-seeding is the most frequently utilized planting practice in Arkansas and Mid-South rice (Oryza sativa L.) production. Enhanced plant density and more rapid rice canopy formation may result from the implementation of innovative plant arrangements and spacings. Studies were initiated in 2019 and continued into 2020 to examine different cultural management practice experiments, including evaluating the impacts of planting arrangement, row spacing, and seeding rates on rice stand density, canopy coverage, grain yield, and milling yield. These small-plot trials were conducted at two locations, a silt loam site and a clay site, representative of soils produced to rice in eastern …

Data Analytics For Sustainable Food And Agriculture Systems, Megan Lord Reavis

Graduate Theses and Dissertations

The increasing concentration of anthropogenic greenhouse gases in the atmosphere is altering the climate, posing a serious threat to global agriculture and food security. Agriculture and food production contribute a quarter of all GHG emissions produced, so there is a critical need to limit emissions in this area while increasing food production to feed the anticipated 10 billion people by 2050. To address the needs of the future, data-driven solutions are needed to guide decision-making and provide support for actionable climate mitigation and survival strategies. Research efforts must be focused on analyzing problems on multiple scales, identifying new ways to …

Evaluation Of Irrigation And Nutrient Management Strategies In Rice Using Alternative Irrigation Methods, Justin Lee Chlapecka

Graduate Theses and Dissertations

As water resources gain value across the Mid-South, alternative irrigation strategies of rice (Oryza sativa L.) have garnered increasing attention. In 2015, an estimated 1.7% of Arkansas rice hectarage used alternate wetting and drying (AWD) irrigation and 0.9% used furrow irrigation. As of 2020, 2.5% used AWD and 16.9% used furrow irrigation, the latter accounting for near 99,000 ha in Arkansas. Little information exists in the scientific literature in relation to management of rice grown in the Mid-South without a conventional flood. This fact coupled with the rapid adoption rate, especially for furrow-irrigated rice (FIR), during the last five years …

Optimization Of Broken Rice Consumption Through Understanding The Confluence Of Sensory And Economic Preferences, Matthew Greer Richardson

Graduate Theses and Dissertations

The authors were perplexed by the seeming dichotomy between the majority 70% of Haitian consumers being chronically food insecure, but still preferring to pay premium international market prices for long-grain rice that constitutes 30% of the calories in this poorest nation in the Western Hemisphere. The aim of this study was to determine the optimal percent broken rice in regards to price specifically to Haiti. Optimization between quality and price point is seen as the best rice for the price, and can be found through combining individual preferences with willingness to pay. Broken rice (brokens) garner a significantly discounted price …

Impacts Of Postharvest Temperature Exposure Profiles On Rice Physicochemical Properties, Seth Graham-Acquaah

Graduate Theses and Dissertations

Heated-air drying followed by tempering (HAT) is effective for increasing rough-rice drying rates without compromising head rice yield (HRY). However, heat exposure could affect rice end-use properties. Hypothesizing that the total amount of heat exposure incurred by rice during heated-air drying determines the trend and magnitude of changes in end-use properties, this dissertation sought to 1) characterize the effects of drying and tempering regimen on changes in end-use properties, 2) derive an index to quantify and compare the amount of heat exposure that rice kernels incur during active drying and, 3) relate values of this index to changes in rice …

Rice Fortification By Parboiling In Limited-Water Soaking To Alleviate Mineral And Vitamin Deficiency, Annegret Jannasch

Graduate Theses and Dissertations

Fortification of rice by parboiling is considered a potential alternative to currently available fortification technologies to produce rice with higher mineral and vitamin content significantly contributing to nutrient intake in populations with high prevalence of micronutrient deficiencies. Higher nutrient retention rates and improved sensory characteristics are advantages of fortified parboiled rice compared to fortified rice obtained by currently used fortification technologies including dusting, coating, and extrusion. However, conventional parboiling processes employ excess water that presents an environmental hazard if discarded without treatment. Thus, the objective of this study was to evaluate a limited-water soaking method for the fortification of rice …

The Economics Of On-Farm Rice Drying In Arkansas, Clayton J. Parker, Lanier Nalley

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

Globally, rice producers are faced with the temporal problem of deciding the optimal time to harvest rice. When harvested, paddy rice is typically at a harvest moisture content (HMC) between 15% and 22% and subsequently dried by the mill to a moisture content (MC) of 12.5%. Riceland Foods Inc., the largest miller of rice in the world, uses a stair-step pricing model to charge farmers to dry, which can complicate the timing of harvest as producers try to balance the tradeoff of minimizing drying costs by waiting to harvest at lower HMC vs. maintaining higher rice quality typically observed when …

Implications Of Rice Cultivar Selection To Optimize Returns From Crop Insurance, David Ethan Branscum

Graduate Theses and Dissertations

Rice production differs from most other field crops by distinct differences in yields across cultivars and rice producers being paid for yield after post-harvest milling. Using eleven years (2003-2013) of Arkansas harvest data from performance trials in six different locations, hybrids have 19% higher paddy yields and head rice yield rate 1.7% lower than conventional cultivars. Given the 2014 Farm Bill’s emphasis on crop insurance as a risk management tool for producers, these variations in yield among cultivars have significant implications for rice producers. Comparing national level, crop insurance data on corn, soybeans and rice indicates rice producers strongly prefer …

Methane Emissions From Rice Production On A Silt-Loam Soil In Arkansas, Joshua Jeffry Humphreys

Graduate Theses and Dissertations

Methane (CH4) emissions from rice (Oryza sativa L.) production are a source of concern in the environmental and agricultural communities. New and/or revised agronomic methodologies will be needed to identify production practice combinations that reduce CH4 emissions without decreasing yields. The objective of this multi-year study was to evaluate the effects of water management (i.e., full-season flood and mid-season drain) (2015), cultivar (i.e., pure-line cultivar ‘LaKast’ and the RiceTec hybrid “XP753”) (2015), soil organic matter (SOM) concentration (2016), and tillage [conventional tillage (CT) and no-tillage (NT)] and urea-based fertilizers [N-(n-butyl) thiophosphoric triamide (NBPT)-coated urea and non-coated urea] (2017) on CH4 …

Development And Characterization Of Rice Genotypes For Water Use Efficiency And Drought Resistance, Anuj Kumar

Graduate Theses and Dissertations

Rice, the second largest staple food crop, uses 30% of global fresh water to complete its life cycle worldwide. Water deficits worldwide have become a serious problem affecting rice growth and ultimately grain yield. To solve the water problem globally, improvement of water use efficiency (WUE) and other drought resistance (DR) traits in rice genotypes would be a useful strategy using advanced genomics tools. In this study, our objectives were to 1) analyze phenotypes of the USDA rice mini-core collection (URMC) for WUE and DR related traits, 2) correlate drought response phenes for physiological traits and grain yield in the …

Development Of A One Pass Microwave Heating Technology For Rice Drying And Decontamination, Deandrae Lynette Smith

Graduate Theses and Dissertations

An industrial microwave (MW) system operating at 915 MHz frequency was used to dry high moisture content (MC) (23% to 24% wet basis) medium-grain rough rice samples (cv. Jupiter). The rice beds were contained in a modified tray that accommodated up to 9 kg of rice separated by thin fiberglass mesh in 3 kg increments. Each layer of rice was fitted with fiber optic sensors connected to a real time data logger during MW treatments. It was determined that drying rice to a MC of 14% to 16% was feasible with the application of MW specific energy at 600 kJ/kg-grain …

Microbes In Rough Rice – Prevalence, Growth Kinetics And Links To Dry Matter Loss, Supriya Thote

Graduate Theses and Dissertations

The prevalence of microorganisms on freshly-harvested long-grain hybrid, long-grain pureline, and medium-grain rice has not been elucidated. The first objective of this two-part study was to determine the relative prevalence of microbes on freshly-harvested, high moisture content rice of different types and cultivars. The total and surface aerobic plate counts (APC) and mold counts were determined in terms of log10 colony forming units per gram of rice (log10 CFU/g) for six rice cultivars over two years. In 2013, among harvested samples of all the studied rice cultivars, the long-grain hybrid cultivars had the lowest APC levels (M = 8.10, SD …

Effects Of Delayed Drying And Storage Conditions On Milling, Color, And Viscosity Properties Of Rice, Kathryn Nicole Haydon

Graduate Theses and Dissertations

Head rice yields (HRYs), kernel discoloration, and functional properties are three hallmarks of rice quality, and can be impacted after harvest by storage conditions. This study evaluated impacts on rice quality due to controlled storage at moisture contents (MCs), temperatures, and storage durations that may be incurred during Mid-South rice farming practices. Three hybrid, long-grain cultivars, harvested in Arkansas in 2014 and 2015, were stored in rough rice form at 4 MCs (12.5%, 16%, 19%, and 21%), and 5 temperatures (10°C, 15°C, 20°C, 27°C, and 40°C), for 16 weeks, with samples taken every 2 weeks. After drying and milling, HRYs, …

A Simulation Platform For Accurate Prediction Of In-Bin Drying And Storage Of Rough Rice, Houmin Zhong

Graduate Theses and Dissertations

Natural air (NA), in-bin drying and storage of rough rice generally maintains high grain quality, but the associated slow movement and occasional stagnation of the drying front during the process may result in problems of rice quality reduction, mold growth, and mycotoxin development, especially for rough rice in the top layers of the bin. Using modeling techniques to simulate in-bin rough rice drying in typically-encountered field scenarios may provide a tool for rapidly predicting the grain condition as drying progresses. The objectives for this study were to (1) investigate accurate models for predicting equilibrium moisture content (EMC) of rough rice …

Effect Of Germination And Parboiling On Milling, Physicochemical, And Textural Properties Of Medium- And Long-Grain Rough Rice, Ashley Han

Graduate Theses and Dissertations

Germinated brown rice is commonly consumed in Asia for its enhanced nutritional properties such as gamma-aminobutyric acid (GABA) and softer cooked texture. However germination decreases milling yield and alters some physicochemical properties, and most germinated rice studies evaluated medium-grain and aromatic rice cultivars. This study compared the effects of germination duration and parboiling on milling, physicochemical, and textural properties of a medium- (Jupiter) and a long-grain (Wells) rice cultivars. Rough rice was soaked in water at 25°C for 12 hr, and then incubated at 30-34°C for varying germination durations, or combined with parboiling at 120°C for 20 min prior to …

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 …

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. …

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 …

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, …

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 …

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 …

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

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 …