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Full-Text Articles in Life Sciences

Rice Response To Nitrogen Fertilization And Comparison Of Unmanned Aerial Systems And Active Crop Canopy Sensors Vegetative Index To Estimate Rice Yield Potential, Anna Coker Nov 2019

Rice Response To Nitrogen Fertilization And Comparison Of Unmanned Aerial Systems And Active Crop Canopy Sensors Vegetative Index To Estimate Rice Yield Potential, Anna Coker

LSU Master's Theses

Nitrogen (N) fertilization is a key component in producing profitable, maximized rice grain yields because yield is directly affected by N fertilizer applications. Economical optimum N rate (EONR) is used to estimate where the N fertilization rate impacts rice grain yield but is still economically efficient. Three common response models, linear-plateau, quadratic-plateau, and quadratic models were used to determine the response of rice to N fertilizer to determine the optimum N fertilization rate. The objective of the first part of this study was to evaluate the models by assessing the coefficients of determination (R2), maximum rice grain yields …


Strategies To Overcome Antagonism Of Quizalofop-P-Ethyl When Applied In Mixture With Other Herbicides, Lucas C. Webster Mar 2019

Strategies To Overcome Antagonism Of Quizalofop-P-Ethyl When Applied In Mixture With Other Herbicides, Lucas C. Webster

LSU Master's Theses

A field study was conducted in 2017 and 2018 at the LSU Agricultural Center H. Rouse Caffey Rice Research Station (RRS) near Crowley, LA. to evaluate the influence of different adjuvants in overcoming the antagonism of quizalofop when mixed with bispyribac in Louisiana rice production. The antagonism of quizalofop mixed with bispyribac plus HCOC at 14 DAIT was overcome with a neutral interaction observed at 28 DAIT for barnyardgrass control with an observed control of 91%, compared with an expected control of 97%. The addition of COC, SNS or HCOC into a mixture of quizalofop plus bispyribac provided synergistic or …


Quizalofop-P-Ethyl Herbicide Interactions In Accase-Resistant Rice Production, Samer Y. Rustom Jr. Jan 2017

Quizalofop-P-Ethyl Herbicide Interactions In Accase-Resistant Rice Production, Samer Y. Rustom Jr.

LSU Master's Theses

A field study was conducted in 2015 and 2016 at the H. Rouse Caffey Rice Research Station (RRS) to evaluate mixture interactions of quizalofop and ALS-inhibiting herbicides. Quizalofop was applied at 120 g ai ha-1. Mixture herbicides included penoxsulam at 40 g ha-1, penoxsulam plus triclopyr at 352 g ha-1, halosulfuron at 53 g ha-1, bispyribac at 34 g ha-1, orthosulfamuron plus halosulfuron at 94 g ha-1, orthosulfamuron plus quinclorac at 491 g ha-1, imazosulfuron at 211 g ha-1, and bensulfuron at 43 g ha-1. All ALS herbicides mixed with quizalofop indicated antagonistic responses for weedy rice or barnyardgrass control …


Nealley's Sprangletop (Leptochloa Nealleyi Vasey) Management And Interference In Rice Production, Eric Allen Bergeron Jan 2017

Nealley's Sprangletop (Leptochloa Nealleyi Vasey) Management And Interference In Rice Production, Eric Allen Bergeron

LSU Master's Theses

A glasshouse study was conducted on the Louisiana State University campus in Baton Rouge to evaluate herbicide activity on Nealley's sprangletop. Herbicides were applied to Nealley’s sprangletop plants in the one-two tiller stage with height of 20-30 cm. Nealley's sprangletop control, leaf number, height, tiller number, and fresh weight biomass were evaluated. Nealley's sprangletop treated with glyphosate, quizalofop, fenoxaprop, and clethodim was controlled 89 to 99%. A field study was conducted at the LSU AgCenter Rice Research Station (RRS) and a grower location (GL) to evaluate herbicide rates and timings for control of Nealley's sprangletop in drill-seeded rice. Herbicide treatments …


Molecular Genetics Of Cold Tolerance At Germination And Seedling Stages In Rice, Anna Hissahe Borjas Artica Jan 2017

Molecular Genetics Of Cold Tolerance At Germination And Seedling Stages In Rice, Anna Hissahe Borjas Artica

LSU Master's Theses

Low temperature stress is a major constraint for rice production in temperate and high altitude areas of the world. Delayed germination coupled with reduced seedling vigor hinders crop establishment and crop growth resulting in reduced rice productivity. Mapping of chromosomal regions controlling cold tolerance will accelerate marker-assisted breeding of cold tolerant rice varieties. A recombinant inbred line (RIL) mapping population involving a rice cultivar ‘Bengal’ and a US weedy rice accession ‘PSRR-1’ was evaluated for cold tolerance at both germination and seedling stages. Observations on germinating ability and seedling vigor were recorded under both low temperature (13oC) and optimum temperature …


Effects Of Detrital Subsidy On Arthropod Communities In Louisiana Rice Fields And Predation On Rice Water Weevil (Lissorhoptrus Oryzophilus), Nathan Mercer Jan 2015

Effects Of Detrital Subsidy On Arthropod Communities In Louisiana Rice Fields And Predation On Rice Water Weevil (Lissorhoptrus Oryzophilus), Nathan Mercer

LSU Master's Theses

The rice water weevil (RWW), Lissorhoptrus oryzophilus (Kuschel), is the most important insect pest of rice in the United States. Integrated pest management strategies for RWW in Louisiana consist of cultural controls, resistant cultivars and chemical insecticides. The fourth component of IPM, biological control, is largely absent from the literature for RWW, making exploration of biological control a logical next step in developing a full set of IPM strategies. The three main types of biological control are augmentation, classical and conservation. With little known about RWW predators, conservation biological control makes the most sense as local natural enemy abundance is …


Development Of A Loop-Mediated Isothermal Amplification For The Detection Of Burkholderia Glumae, Maria Alejandra Caldera Jan 2014

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 …


Physiological, Biochemical And Molecular Characteristics Associated With Virulence Of Burkholderia Glumae: The Major Causative Agent Of Bacterial Panicle Blight Of Rice, Hari Sharan Karki Jan 2010

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 …


Economic Evaluation Of Potential Changes In Farm Program Price Support For Typical Louisiana Rice And Cotton Farming Operations, Manuel E. Aldana Jan 2005

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 …


An Evaluation Of Cost Of Production Insurance As An Income Support Tool For Rice And Cotton Producers In Louisiana, Erica Harding Jan 2004

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 Jan 2004

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 …


Resistant Rice Starch Development, Siow Ying Tan Jan 2003

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 …


Economic Evaluation Of Alternative Rough Rice Marketing And Storage Strategies, April Street Jan 2002

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 …