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Full-Text Articles in Life Sciences
Environmental And Agronomic Evaluation Of Struvite In Rice Production Systems, Diego Della Lunga
Environmental And Agronomic Evaluation Of Struvite In Rice Production Systems, Diego Della Lunga
Graduate Theses and Dissertations
Furrow-irrigation constitutes an alternative water regime that has been increasingly adopted in Arkansas. Among the management of nutrients in furrow-irrigated systems, phosphorus (P) represents a substantial challenge. The environmental sustainability of rice (Oryza sativa) production systems needs to be evaluated across different water regimes and fertilizer-P sources. Therefore, the objectives of the following studies were to: i) evaluate season-long carbon dioxide (CO2) and methane (CH4) emissions and global warming potential (GWP) under different tillage treatments [i.e., conventional tillage (CT) and no-tillage (NT)] and at different site positions (i.e., up-, mid-, down-slope) along the predominant slope of a production-scale, furrow-irrigated rice …
Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter
Evaluation Of Weed Control Efficacy And Crop Tolerance To Florpyrauxifen-Benzyl Coated Onto Urea, Bodie Lyn Cotter
Graduate Theses and Dissertations
Frequent off-target movement occurrences to soybean [Glycine max (L.) Merr.], rice (Oryza sativa L.) injury, and a lack of barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] control followed the commercial launch of florpyrauxifen-benzyl in 2018. Florpyrauxifen-benzyl is a synthetic auxin, Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 4 herbicide used for postemergence weed control in rice and labeled for application at 30 g ae ha-1. Previous research documented that soybean was susceptible to injury following spray applications of florpyrauxifen-benzyl at less-than-labeled rates, and certain varieties of rice are less tolerant to spray-applied florpyrauxifen-benzyl at 30 g ae …
Effect Of Cultural Strategies And Application Technologies On Weed Control In Flooded And Furrow-Irrigated Rice, Noah Hunter Reed
Effect Of Cultural Strategies And Application Technologies On Weed Control In Flooded And Furrow-Irrigated Rice, Noah Hunter Reed
Graduate Theses and Dissertations
Weed control is a major problem that rice (Oryza sativa L.) producers face in the Mid-south every growing season. Restricted use of some rice herbicides has also highlighted the need for more research to be conducted on cultural weed control strategies and application technologies in rice. The aim of these studies was to evaluate rice weed control using various rice row widths, bed widths (irrigation-furrow spacing), rice cultivar selection, and nozzle type selection. Three field experiments were conducted in 2021 and 2022 across four sites at Lonoke, AR, Pine Tree, AR, Rohwer, AR, and Stoneville, MS. In experiment one, as …
Evaluation Of Benzobicyclon In Midsouth Rice (Oryza Sativa) Production Systems, Jake Patterson
Evaluation Of Benzobicyclon In Midsouth Rice (Oryza Sativa) Production Systems, Jake Patterson
Graduate Theses and Dissertations
Controlling weedy rice postemergence is challenging for rice producers in the United States because of the lack of herbicide options. Weedy rice is genetically similar to cultivated rice, thus making it difficult to control with mid-season postemergence herbicide applications without also damaging the crop. Hence, there is a need for a new effective postemergence weedy rice control herbicide. Findings from this research indicate that the use of benzobicyclon in current standard quizalofop- and imidazolinone-resistant rice herbicide programs provides tremendous utility for Midsouth rice producers. In both of these production systems, the addition of benzobicyclon to the respective standard herbicide programs …
Precise Nitrogen Recommendations Improve Economic And Environmental Outcomes In Arkansas Rice Production, Cristin Roberts
Precise Nitrogen Recommendations Improve Economic And Environmental Outcomes In Arkansas Rice Production, Cristin Roberts
Graduate Theses and Dissertations
Soil testing has become an increasingly important tool in making agronomically efficient production management decisions. N-STaR is a N test used in rice production and is unique in its ability to selectively quantify soil organic-N compounds which are readily mineralizable for plant N uptake and contribute to growth and yield. This study uses historical (2002–2018) adoption rates of N-STaR, which is funded through Rice Checkoff funds, to calculate the total cost savings from N-STaR adoption. These cost savings alone would be the “typical” benefits used in a benefit-cost ratio of a public ally funded research program like N-STaR. However, we …
Starter Nitrogen Source And Preflood Nitrogen Rate Effects On Rice Grown On Clay Soils, Linda Rachelle Martin
Starter Nitrogen Source And Preflood Nitrogen Rate Effects On Rice Grown On Clay Soils, Linda Rachelle Martin
Graduate Theses and Dissertations
Seedling rice (Oryza sativa L.) grown on clayey-textured soils generally develops slowly as compared to loamy-textured soils. Our research examined the effects of starter-N source and preflood-N rates on canopy closure, total aboveground N uptake, and grain yield of rice grown on clayey-textured soils. Eleven field trials were established in Arkansas and Mississippi including five trials with a hybrid cultivar and six trials using a pure-line cultivar. Starter-N sources included no starter-N (NONE), ammonium sulfate (AMS), diammonium phosphate (DAP), and urea (UREA) applied at 24 kg N ha-1 at the rice 2-leaf stage and five preflood-N rates ranging from 0-224 …
Evaluation Of Irrigation And Nutrient Management Strategies In Rice Using Alternative Irrigation Methods, Justin Lee Chlapecka
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 …
Parallel Strategies To Control Bacterial Panicle Blight Of Rice, Laura Ortega
Parallel Strategies To Control Bacterial Panicle Blight Of Rice, Laura Ortega
Graduate Theses and Dissertations
Bacterial Panicle Blight (BPB) of rice is a seed-borne disease caused by the bacterium Burkholderia glumae. This disease has affected rice production worldwide and its effects are likely to become more devastating with the continuous increase in global temperatures especially during the growing season. Field data has shown that the disease has been more prevalent in years when the temperatures have been unusually high especially at night possibly due to the bacterial adaptation to grow at temperatures higher than 40oC. With the continuous rise in global temperatures, it is likely that this disease will be more problematic. The bacterium can …
Characterization Of Genetic Sources Associated With Restorability And Seed Dimension In Arkansas Restorer Rice Lines, Ozgur Azapoglu
Characterization Of Genetic Sources Associated With Restorability And Seed Dimension In Arkansas Restorer Rice Lines, Ozgur Azapoglu
Graduate Theses and Dissertations
Hybrid rice (Oryza sativa L.) breeding offers a significant opportunity to enhance rice production, and the cultivation of a male sterile line is the most important factor in the success of cross-breeding. One of the key elements of hybrid rice production is to develop a restorer line that is assigned as the male parent. The restorer lines provide viable pollen for fertilization of the male sterile plant due to the presence of a restorer gene (Rf) in their genomes. Any superior restorer line applied to hybrid rice production must contain genes/quantitative trait loci (QTL) associated with the desirable agronomic traits …
Molecular Genetic Analysis Of Drought Resistance And Productivity Traits Of Rice Genotypes, Yheni Dwiningsih
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 …
Determination Of Critical Y-Leaf Potassium Concentrations Across Reproductive Growth Stages For Direct-Seeded Delay-Flooded Rice, Chandler Edwin Gruener
Determination Of Critical Y-Leaf Potassium Concentrations Across Reproductive Growth Stages For Direct-Seeded Delay-Flooded Rice, Chandler Edwin Gruener
Graduate Theses and Dissertations
Rice (Oryza sativa L.) grain yield can be limited by potassium (K) deficiency on soils low in exchangeable K. Visually diagnosing K deficiency during early reproductive growth is not easily done and the interpretation of traditional tissue analysis is limited to select growth-stages. Our primary focus was to define continuous critical Y-leaf-K concentrations during reproductive growth for the production of maximal grain yield. A secondary objective was to examine Y-leaf sap-K concentration, measured using a handheld device, as a rapid in-field method of monitoring rice plant K nutrition. The Y-leaf is defined as the uppermost fully extended leaf with a …
Qtl Mapping Of Panicle Architecture And Yield-Related Traits Between Two U.S. Rice Cultivars 'Lagrue' And 'Lemont', Adam D. Rice
Qtl Mapping Of Panicle Architecture And Yield-Related Traits Between Two U.S. Rice Cultivars 'Lagrue' And 'Lemont', Adam D. Rice
Graduate Theses and Dissertations
Grain yield in rice consists of multiple yield components such as number of panicles/plant, number of tillers/plant, and number of seeds/panicle. Panicle architecture is an important yield trait yield as the number of seeds on a panicle greatly contributes to the overall panicle yield. A QTL analysis and mapping study on panicle architecture and yield-related traits was performed to identify major QTL and candidate genes associated with the traits. The first objective of the project was to do a yield study evaluating 15 agronomic traits between each of the four U.S. rice cultivars, ‘LaGrue’, ‘Lemont’, ‘Bengal’, and ‘Mars’, to determine …
Evaluation Of Insecticide Seed Treatments To Protect Rice (Oryza Sativa) Against Various Herbicides, Steven Michael Martin
Evaluation Of Insecticide Seed Treatments To Protect Rice (Oryza Sativa) Against Various Herbicides, Steven Michael Martin
Graduate Theses and Dissertations
The increase in herbicide-resistant weeds in Arkansas crop fields has led to the need for new herbicide modes of action for use in all crops. This need has led to the introduction of technologies that can be devastating to conventional rice crops. Field observation, noted that insecticide seed treatments used in rice could potentially reduce the effects of off-target movement of herbicides onto rice crops and possibly reduce the negative effects of some herbicides applied directly to rice. Research was conducted to determine if insecticide seed treatments could reduce the harmful effects of drift from imazethapyr and glyphosate onto conventional …
Characterization Of Candidate Compound For Control Of Barnyardgrass And Other Troublesome Weeds In Rice, Michael Ryan Miller
Characterization Of Candidate Compound For Control Of Barnyardgrass And Other Troublesome Weeds In Rice, Michael Ryan Miller
Graduate Theses and Dissertations
Barnyardgrass remains one of the most difficult weeds to manage in rice. As herbicide resistance in this species, as well as others, continues to increase new control options are needed. Dow AgroSciences recently discovered and is developing a new herbicide for rice which is the primary focus of this research. Experiments were conducted to characterize this new herbicide for its use and effectiveness in midsouthern U.S. rice systems. The research conducted herein covers various aspects of herbicide characterization including: barnyardgrass dose response, accession testing, spectrum of control and tank-mix capability, application optimization, soil carryover and plant back determination, drift onto …
Preserving Rice Quality: Fine-Mapping And Introgressing A Fissure Resistance Locus, Haley Marie Sater
Preserving Rice Quality: Fine-Mapping And Introgressing A Fissure Resistance Locus, Haley Marie Sater
Graduate Theses and Dissertations
Rice (Oryza sativa L.) kernel fissuring is a major concern of both rice producers and millers. Fissures are small cracks in rice kernels that increase breakage of kernels when milled, and decrease the value of processed rice. This study employed molecular gene tagging methods to fine-map a fissure resistance (FR) locus found in ‘Cybonnet’, a semidwarf tropical japonica cultivar, as well as transfer this trait to rice genotypes of taller, non-semidwarf plant height that are better adapted to some rice production systems. Three QTLs for FR were previously reported; the FR locus with strongest effect resides near the semidwarf sd-1 …
The Effects Of Salinity On Pythium Disease Of Rice And Soybean, Terea Jeanette Stetina
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 …
Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher
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
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. …
Multifunctionality In U.S. Rice Production: A Logit Analysis In Farmers Participation, Juan Tur Cardona
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
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 …