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Phenotyping Cotton Compactness Using Machine Learning And Uas Multispectral Imagery, Joshua Carl Waldbieser Dec 2023

Phenotyping Cotton Compactness Using Machine Learning And Uas Multispectral Imagery, Joshua Carl Waldbieser

Theses and Dissertations

Breeding compact cotton plants is desirable for many reasons, but current research for this is restricted by manual data collection. Using unmanned aircraft system imagery shows potential for high-throughput automation of this process. Using multispectral orthomosaics and ground truth measurements, I developed supervised models with a wide range of hyperparameters to predict three compactness traits. Extreme gradient boosting using a feature matrix as input was able to predict the height-related metric with R2=0.829 and RMSE=0.331. The breadth metrics require higher-detailed data and more complex models to predict accurately.


The Influence Of At-Planting Insecticide Treatments On Tobacco Thrips, (Thysanoptera:Thripidae), And Reniform Nematode, (Tylenchida:Hoplolaimidae), In Conventional And Thryvon Cotton Systems, Walker Brett Farmer Dec 2023

The Influence Of At-Planting Insecticide Treatments On Tobacco Thrips, (Thysanoptera:Thripidae), And Reniform Nematode, (Tylenchida:Hoplolaimidae), In Conventional And Thryvon Cotton Systems, Walker Brett Farmer

Theses and Dissertations

One of the objectives of this research was to evaluate the need for an additional imidacloprid seed treatment on ThryvOn® (Bayer Crop Science®, St. Louis, MO) cotton to effectively manage tobacco thrips, Frankliniella fusca (Hinds). While evaluating thrips densities and damage ratings, ThryvOn cotton continued to display reduced damage and thrips populations than non-ThryvOn. Thrips populations and damage ratings were consistently reduced when incorporating a higher rate of imidacloprid, but they were not reduced enough to justify the higher rates of imidacloprid. Another objective of this research was to evaluate the impact of aldicarb (AgLogic Chemical® …


Integrating Weed-Suppressive Cotton Chromosome Substitution Lines And Cover Crops For Sustainable Weed Management In Cotton Production Systems., Alyssa Lea Miller Aug 2023

Integrating Weed-Suppressive Cotton Chromosome Substitution Lines And Cover Crops For Sustainable Weed Management In Cotton Production Systems., Alyssa Lea Miller

Theses and Dissertations

Weeds pose a challenge to cotton production, and herbicides have been the primary means of control. However, there is growing concern over weed resistance to herbicides. To address this issue, we evaluated three cover crop species and six cotton accessions for weed suppression. The study found that hairy vetch, wheat, and B16 cotton CS line effectively suppressed Amaranthus species, while MNTN 4-15, B16, hairy vetch, and wheat were correlated with the highest cotton yield. Cover crops were also analyzed for chlorogenic acid content, with wheat, MNTN 4-15, and hairy vetch producing the highest amounts. The greenhouse tray study showed that …


Robotic Cotton Harvesting With A Multi-Finger End-Effector: Research, Design, Development, Testing, And Evaluation, Hussein Gharakhani May 2023

Robotic Cotton Harvesting With A Multi-Finger End-Effector: Research, Design, Development, Testing, And Evaluation, Hussein Gharakhani

Theses and Dissertations

Cotton is harvested with large and heavy machines that are very efficient but have some disadvantages. They can harvest the crop only once at the end of the growing season. Since cotton bolls do not mature uniformly, the early opened bolls expose their fiber to weather for extended periods, reducing lint quality. In addition, the machines can also compact the soil, reducing water and fertilizer usage efficiencies and crop yields in the following years. Robotic cotton harvesting offers a promising solution to these issues. Smaller robotic harvesters could go to the field multiple times during the season to pick cotton …


Inline Real Time Moisture Sensing For Gin Cotton, Lucas Gay May 2023

Inline Real Time Moisture Sensing For Gin Cotton, Lucas Gay

Theses and Dissertations

The objective of this study was to assess the performance of a capacitive sensor in measuring moisture content of cotton within the moisture range of 6-13%. The assessment was conducted in two phases: static and dynamic. During the static phase, models to predict moisture content were created and a 95% Confidence Interval of [-0.619,0.619], Percent Residual Accuracy of 97.586%, and a mean error of 4.396% were achieved. The Bland-Altman plot yielded a curve with a slight positive trend, suggesting the data could be modeled more appropriately by multiple models. The dynamic phase saw similar results as the static tests in …


Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker Aug 2022

Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker

Theses and Dissertations

Nitrogen run-off from agriculture have been linked to human health problems on a global level. Large-scale conventional producers struggle to redefine themselves as sustainable because reducing nitrogen (N) inputs without justification or validation may lead to severe profit losses. Small unmanned aerial systems (sUAS) sensing may allow for decreased N runoff. Failure to address this problem will exacerbate already excessive N runoff into the Mississippi River and beyond. The purpose of this study was to reduce fertilizer N input using sUAS technology to assess crop canopy needs. In 2020 and 2021, variable rate nitrogen (VRN) side-dress N application maps were …


Novel Applications In Mississippi Cotton And Peanut, Anna Beth Gaudin Aug 2022

Novel Applications In Mississippi Cotton And Peanut, Anna Beth Gaudin

Theses and Dissertations

Studies were conducted in the field from 2020-2021 in peanut and cotton to optimize peanut growth and yield through prohexadione calcium application methods as well as weed control through increasing herbicide sites of action. These studies were established on multiple on-farm and small-plot locations in Mississippi. Prohexadione calcium studies concluded that following application of prohexadione calcium effects on yield and peanut growth were inconsistent. Neither varying application timing nor rate resulted in peanut yield that was different than when adhering to the label recommendations. Increasing sites of action studies concluded that broadleaf signalgrass and Amaranthus species control was optimized at …


Evaluation Of Non-Labeled Herbicides In Cotton Production In Mississippi, Zaim Ugljic May 2022

Evaluation Of Non-Labeled Herbicides In Cotton Production In Mississippi, Zaim Ugljic

Theses and Dissertations

Weed resistance has decreased the number of herbicides that provide effective weed control in cotton. Studies were conducted to determine weed control efficacy and crop safety in cotton with herbicides not currently labeled for use in the crop. Herbicides were applied at two different timings near Starkville and Brooksville, MS. Cotton injury following application of ametryn, bentazon, florpyrauxifen-benzyl, topramezone and tolpyralate at the 3-5 or the 8-10 node growth stage ranged from 24 to 43% and 15 to 51%, respectively, up to 56 days after application. Except for bentazon, applying non-labeled herbicides to cotton at the 3-5 or 8-10 node …


Impact Of Row Spacing/Planting Pattern And Seed Size On Plant Development And Yield On Cotton (Gossypium Hirsutum L.)., Steven Dale Hall May 2022

Impact Of Row Spacing/Planting Pattern And Seed Size On Plant Development And Yield On Cotton (Gossypium Hirsutum L.)., Steven Dale Hall

Theses and Dissertations

There is renewed interest in cotton performance grown using various row spacings and plantings patterns in the Midsouth. Cotton seed size has been reduced compared to sixty years ago. Planting smaller seeds is concerning due to having less energy for emergence as well as complicating the ginning process. Two row spacings, two planting patterns, and two cotton varieties were evaluated over eight site years from 2019-2020. The solid planting pattern produced a higher yield on a land area basis. In addition, two varieties, each with three seed counts, were planted at three seeding rates and evaluated over six site years …


Determining Residual Control And Systemic Activity Of Commonly Used Insecticides In Soybean And Cotton, Jacob H. Smith May 2022

Determining Residual Control And Systemic Activity Of Commonly Used Insecticides In Soybean And Cotton, Jacob H. Smith

Theses and Dissertations

Chemical control is a critical component of integrated pest management in cotton and soybean production. Residual efficacy of foliar insecticides can be highly variable and difficult to quantify due to several factors. The purpose of this research was to determine residual control and concentrations in flowering structures of commonly used insecticides. This research focused on the concentrations of active ingredient within the plant as well as efficacy over time. Previous research suggested chlorantraniliprole had a long residual and was highly lethal on corn earworm up to 28 days after treatment (DAT) in soybean; however, the results found in cotton were …


Seasonal Management Strategies For Tarnished Plant Bug, Lygus Lineolaris (Palisot De Beauvois), In Midsouth Cotton Production Systems, Ryan Taylor Mann Dec 2021

Seasonal Management Strategies For Tarnished Plant Bug, Lygus Lineolaris (Palisot De Beauvois), In Midsouth Cotton Production Systems, Ryan Taylor Mann

Theses and Dissertations

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is considered the most economically important pest of midsouth cotton. This study was designed to understand the impact of tarnished plant bug populations in the later weeks of flowering cotton and residual effects of novaluron with subsequent applications. Experiments evaluated dynamic threshold approaches in the later flowering period of midsouth cotton, the impacts of novaluron plus subsequent applications at the 3rd week of square, as well as residual properties in a laboratory experiment. Results suggest that a dynamic late season approach can reduce the amount of insecticide applications targeting tarnished …


Design Of Plastic Contaminant Eliminator In Seed Cotton, Joshua H. Tandio Dec 2021

Design Of Plastic Contaminant Eliminator In Seed Cotton, Joshua H. Tandio

Theses and Dissertations

Plastic contamination in cotton is a problem in cotton industry and researchers have worked on this problem with different approaches. This thesis documents the design of mechanical and electronic real-time systems for detecting and removing plastic contaminants. The mechanical system was designed to expose plastic embedded inside the seed cotton to the sensor and to separate plastic contaminated cotton from the process stream. The detection system consisted of an embedded computer interfaced with a USB camera and Neural Network (NN) software running in it. Two NN models were tested, a transfer learning model and a built-from-scratch original model. The original …


Using Weed-Suppressive, Chromosome Substitution (Cs) Cotton As A Supplemental Weed Management Strategy, Mary Gracen Alexandra Fuller Aug 2021

Using Weed-Suppressive, Chromosome Substitution (Cs) Cotton As A Supplemental Weed Management Strategy, Mary Gracen Alexandra Fuller

Theses and Dissertations

Cotton is a valuable fiber crop around the world used to create fabrics, oils, and currency. The threat of herbicide resistant (HR) weed populations is precarious for cotton production. The overreaching objective of this study was to phenotype potentially allelopathic chromosome substitution (CS) lines to determine competitive accessions. The identification of competitive cotton lines would be useful in the development of alternative weed control tools. Twelve CS lines (CS-49, CS-38, CS-34, CS-39, CS-27, CS-13, CS-50, CS-26, CS-25, CS-43, CS-46, and CS-23) along with the parent line (TM1) and two conventional varieties (UA48 and Enlist) were screened in a greenhouse using …


Evaluating The Management Of Bollworm (Lepidoptera: Noctuidae) In Cotton, Michael Cade Francis Apr 2021

Evaluating The Management Of Bollworm (Lepidoptera: Noctuidae) In Cotton, Michael Cade Francis

Theses and Dissertations

In field experiments, thresholds, spray timings, and bollworm oviposition were conducted to evaluate the current recommended action thresholds for bollworm (Lepidoptera: Noctuidae) in cotton. Based on studies conducted evaluating thresholds, insecticide applications varied across Bt technologies. Bollgard 3 required less sprays when compared to Bollgard II and non-Bt. A second experiment highlighted the importance of timely insecticide applications for managing bollworm populations in Bollgard II cotton based on insect damage. The highest yields were associated with insecticide applications made during the timeframe that cotton is the most susceptible to bollworm damage. The last experiment was conducted to determine if oviposition …


Evaluation Of The Rainfastness Of Selected Insecticides In Cotton, Sara Inez Barrett Apr 2021

Evaluation Of The Rainfastness Of Selected Insecticides In Cotton, Sara Inez Barrett

Theses and Dissertations

Rainfastness of insecticides is an understudied aspect of agricultural research. Little is known about the residual of commonly used products for key pests of cotton, as well as their residual after a rainfall event. This project was designed to evaluate the impact of rainfall on the performance of commonly used insecticides for tobacco thrips, Frankliniella fusca (Hinds); tarnished plant bug, Lygus lineolaris (Palisot de Beauvois); and bollworm, Helicoverpa zea (Boddie), management in cotton. Laboratory and field experiments suggest that rainfall occurring within 16 hours after application had a negative impact on the performance of most insecticides. Chemical analyses of leaf …


Evaluation Of Narrow Corn (Zea Mays L.) Production And Management In Mississippi And Management Of Glufosinate Herbicide Applications On Palmer Amaranth (Amaranthus Palmeri) Control In Cotton (Gossypium Hirsutum), John Joseph Williams Apr 2021

Evaluation Of Narrow Corn (Zea Mays L.) Production And Management In Mississippi And Management Of Glufosinate Herbicide Applications On Palmer Amaranth (Amaranthus Palmeri) Control In Cotton (Gossypium Hirsutum), John Joseph Williams

Theses and Dissertations

Narrow row corn production has gained interest in the Mid-South region over the last several years. This narrow row spacing interest has been inspired by increase of soybean grain yield from narrow rows. Therefore, production practices were evaluated for proper management of narrow row corn production. Additionally, the management of glyphosate- and potentially auxin-resistant weeds place pressure on other POST chemistries. Therefore, optimizing glufosinate applications are essential for control of Palmer amaranth. The objectives of this research were four-fold: 1) evaluate the phenotypic and grain yield responses of narrow row corn production under irrigated conditions, 2) test corn hybrids for …


Evaluation Of Bollworm Behavior, Damage, And Control In Cotton With Insecticidal Proteins And Formulated Insecticides, Russell Ethan Godbold Aug 2020

Evaluation Of Bollworm Behavior, Damage, And Control In Cotton With Insecticidal Proteins And Formulated Insecticides, Russell Ethan Godbold

Theses and Dissertations

The bollworm, Helicoverpa zea (Boddie), is an economically important pest of cotton and is becoming more difficult to control in the United States. This project was designed to develop a better understanding of the effects of resistance development and plant structures on the efficacy of Bt cotton and foliar insecticides. Experiments examined larval behavior and damage in current cotton varieties expressing proteins from Bacillus thuringiensis. Other experiments examined the effects of floral structures on the control of bollworm using foliar insecticides. Results suggest that larval feeding and avoidance behavior is dependent on point of eclosion. Fruiting form damage increased in …


Evaluation Of Pesticide Application Technology In Cotton Production, Chase Samples May 2020

Evaluation Of Pesticide Application Technology In Cotton Production, Chase Samples

Theses and Dissertations

There have been many changes in production agriculture over the last 20 years. The use of herbicide resistant crops has become common place in production agriculture. However, the release of crops resistant to auxin herbicides has brought more attention to the pesticide application process regardless of the type of pesticide applied. Moreover, controlling off-target movement of pesticides has become an integral part of the day to day farming tasks. The use of deposition aids when applied with water has been documented; however, the effect of deposition aids on pesticide application is not well understood. Based on these findings, selecting a …


Agronomic And Physiological Responses Of Resistant And Susceptible Cotton Genotypes To Reniform Nematode Severity And Soil Nitrogen, Bhupinder Singh May 2020

Agronomic And Physiological Responses Of Resistant And Susceptible Cotton Genotypes To Reniform Nematode Severity And Soil Nitrogen, Bhupinder Singh

Theses and Dissertations

Rotylenchulus reniformis (RN) nematode infection has been identified as a major biotic factor limiting cotton yield (~8%) in Mississippi. Cotton researchers are striving to develop resistance to RN and develop management practices to mitigate the problem. Reniform nematode and soil nitrogen (N) directly affect cotton growth and physiology, however, responses to RN and N may vary across a wide genetic background. The overall objective of this research was to determine the role that host plant resistance to reniform nematode and soil nitrogen plays in cotton growth, physiology, and yield and controlling RN populations. In experiment 1, the effect of RN …


Stewarding 2,4-D- And Dicamba- Based Weed Control Technologies In Cotton And Soybean Production Systems, John Tyler Buol May 2019

Stewarding 2,4-D- And Dicamba- Based Weed Control Technologies In Cotton And Soybean Production Systems, John Tyler Buol

Theses and Dissertations

Distinguishing 2,4-D and dicamba herbicide formulations in cotton and soybean tissue is challenging in regulation of crop injury from these herbicides. Additionally, stewardship of 2,4-D and dicamba technologies is important to maximize their longevity and efficacy. Research was conducted to (1) characterize cotton and soybean response to various formulations of 2,4-D or dicamba with or without glyphosate, (2) develop a method for classifying these formulations in crop tissue, and (3) optimize use of chloroacetamide herbicides in dicamba systems for mitigation of selection pressure on dicamba. Formulations evaluated include dicamba diglycolamine (DGA), dimethylamine (DMA), N,N-Bis-(3-aminopropyl) methylamine (BAPMA), and DGA plus potassium …


Computational Analysis Of Map3k Kinases Across Plant Genomes And Functional Characterization Of A Subset Of Map3ks In Nematode Resistance, Nobert Tamas Bokros Dec 2018

Computational Analysis Of Map3k Kinases Across Plant Genomes And Functional Characterization Of A Subset Of Map3ks In Nematode Resistance, Nobert Tamas Bokros

Theses and Dissertations

Plant MAP3Ks have expanded significantly compared to their metazoan counterparts. A new, sequential workflow combining multispecies ortholog clustering and newly built, family-specific HMMs is used to identify the MAP3K gene family within seven plant species, allowing for a refinement of previously proposed gene family cladding and the novel identification of the MAP3K gene families in the allotetraploid cotton Gossypium hirsutum and newly sequenced monocot seagrass Zostera marina. The MAP3K gene family architecture is further refined and validated using bioinformatics analyses before the recently characterized Arabidopsis Raf-like MAP3K ILK1 is identified and characterized in upland cotton. Transient gene silencing reveals an …


A Transgenic Approach To Managing Tarnished Plant Bug (Hemiptera: Miridae) In Cotton, John Cameron Corbin Aug 2018

A Transgenic Approach To Managing Tarnished Plant Bug (Hemiptera: Miridae) In Cotton, John Cameron Corbin

Theses and Dissertations

Field experiments were conducted in Stoneville, MS and Sidon, MS in 2016 and 2017 to evaluate a new transgenic cotton variety (MON 88702) (Cry51Aa2.834_16) and its effects on tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), populations, frequency of insecticide applications, and yield. Experiments were designed to compare the interactions between the Bt traited plots and non-traited plots and the insecticide spray treatments, which consisted of different application thresholds as well as treatments sprayed only during the early season and only during the late season. MON 88702 provided a significant reduction in later instar tarnished plant bug nymphs, dirty squares, …


Exploration Of The Gossypium Raimondii Genome Using Bionano Genomics Physical Mapping Technology, Christopher Jon Hanson Jun 2018

Exploration Of The Gossypium Raimondii Genome Using Bionano Genomics Physical Mapping Technology, Christopher Jon Hanson

Theses and Dissertations

Cotton is a crop with a large global economic impact as well as a large, complex genome. Most industrial cotton production is from two tetraploid species (Gossypium hirsutum L. and Gossypium barbadense L.) which contain two subgenomes, specifically the AT and DT subgenomes. The DT subgenome is nearly half the size of the AT subgenome in tetraploid cotton and is closely related to an extant D-genome Gossypium species, G. raimondii Ulbr. Characterization of the structural variants present in diploid D-genome should provide greater insight into the evolution of the DT subgenome in the tetraploid cotton. Bionano (BNG) optical mapping uses …


Effects Of Irrigation Scheduling Using Soil Moisture Sensors, Irrigation Termination, And Simulated Damage On Plant Development And Yield On Cotton (Gossypium Hirsutum L.) In The Mid-South, Michael Thomas Plumblee May 2018

Effects Of Irrigation Scheduling Using Soil Moisture Sensors, Irrigation Termination, And Simulated Damage On Plant Development And Yield On Cotton (Gossypium Hirsutum L.) In The Mid-South, Michael Thomas Plumblee

Theses and Dissertations

Through proper irrigation scheduling and management of damaged cotton, sustainable agricultural withdrawal from the Mississippi River Valley Alluvial Aquifer can be achieved while maximizing net returns. This research was conducted to 1) develop a sensor based irrigation strategy that maximized cotton lint yield and quality, irrigation, and water use efficiency (IWUE) and 2) quantify the effects of timing of damage, intensity, and foliar N on cotton growth and development. Lint yield, fiber quality, and IWUE were optimized using a season-long irrigation threshold of -90 kPa and irrigation terminated 2-weeks before cracked boll. Regardless of cotton variety (early- or late-maturing) or …


The Compounding Stresses Of Tobacco Thrips, Frankliniella Fusca (Hinds), And Reniform Nematode, Rotylenchulus Reniformis (Linford & Oliveira), On The Growth And Development Of Cotton, Gossypium Hirsutum L, Whitney Desiree Crow May 2018

The Compounding Stresses Of Tobacco Thrips, Frankliniella Fusca (Hinds), And Reniform Nematode, Rotylenchulus Reniformis (Linford & Oliveira), On The Growth And Development Of Cotton, Gossypium Hirsutum L, Whitney Desiree Crow

Theses and Dissertations

The objectives of this research were to evaluate management options for tobacco thrips, Frankliniella fusca (Hinds), and reniform nematode, Rotylenchulus reniformis (Linford & Oliverira), in cotton productions systems. When evaluating tillage practices for pest control, conservational tillage reduced thrips densities and damage, while the impact on nematode densities is less understood and in this study had no impact. Insecticide seed treatments remain a vital resource for controlling thrips in Mid-South cotton production systems. When incorporating an early season herbicide application for weed control, systems with an insecticide seed treatment generally tolerated herbicide injury better than those with early season stress …


Compounding Factors Affecting The Management Of Thrips (Thysanoptera: Thripidae) In Peanut, Arachis Hypogaea L., And Cotton, Gossypium Hirsutum L., Joel Cary Moor May 2018

Compounding Factors Affecting The Management Of Thrips (Thysanoptera: Thripidae) In Peanut, Arachis Hypogaea L., And Cotton, Gossypium Hirsutum L., Joel Cary Moor

Theses and Dissertations

Experiments were conducted to evaluate the management of thrips (Thysanoptera: Thripidae) in peanut and cotton and the interaction between thrips and tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), in cotton. Although management of thrips with foliar insecticides historically has not been recommended in peanut, the current study observed significant yield benefits from the management of thrips with foliar insecticides. This was especially evident when peanut plants were stressed from herbicide injury. In another experiment, significant differences were observed among cotton varieties in terms of their susceptibility to thrips injury. Finally, an interaction between thrips injury and tarnished plant bug …


The Genome Sequence Of Gossypium Herbaceum (A1), A Domesticated Diploid Cotton, Alex J. Freeman Apr 2018

The Genome Sequence Of Gossypium Herbaceum (A1), A Domesticated Diploid Cotton, Alex J. Freeman

Theses and Dissertations

Gossypium herbaceum is a species of cotton native to Africa and Asia. As part of a larger effort to investigate structural variation in assorted diploid and polyploid cotton genomes we have sequenced and assembled the genome of G. herbaceum. Cultivated G. herbaceum is an A1-genome diploid from the Old World (Africa) with a genome size of approximately 1.7 Gb. Long range information is essential in constructing a high-quality assembly, especially when the genome is expected to be highly repetitive. Here we present a quality draft genome of G. herbaceum (cv. Wagad) using a multi-platform sequencing strategy (PacBio RS II, Dovetail …


Evaluation And Management Of Neonicotinoid Resistant Tobacco Thrips (Frankliniella Fusca) (Hinds) In Cotton, Chelsie Hope Darnell Aug 2017

Evaluation And Management Of Neonicotinoid Resistant Tobacco Thrips (Frankliniella Fusca) (Hinds) In Cotton, Chelsie Hope Darnell

Theses and Dissertations

Research was conducted 2014-2016 to determine how tobacco thrips (Frankliniella fusca) (Hinds) resistance to neonicotinoid insecticides impact thrips resistance to neonicotinoid insecticides in cotton, Gossypium hirsutum (L.).Studies included bioassays to determine severity and mechanism of resistance and evaluation of host plant characteristics in multiple cotton varieties. Another aspect of research focused on the neonicotinoid insecticide clothianidin and its leaching ability as a seed treatment on corn by evaluating soil type, water regime, and amount found in tissue.


Cotton Growth And Developmental Responses To Multiple Environmental Stresses, David William Brand Aug 2016

Cotton Growth And Developmental Responses To Multiple Environmental Stresses, David William Brand

Theses and Dissertations

Individual and multiple stress factor effects of temperature on cotton growth and development were studied in four cotton cultivars. In Experiment I, seedling emergence rate and shoot and root morphological growth traits were measured on plants grown at five day/night temperatures from 20/12 to 40/32 °C. In Experiment II, multiple stress factors (CO2, temperature, UV-B radiation) and their interactions were evaluated during the seedling growth stage. Seed emergence and above- and below-ground growth and developmental traits were recorded in both experiments. Linear (TM-1 and PHY496W3R) and quadratic (DP1522B2XF and ST47447) functions best described seed emergence rate with an increase in …


Best Management Strategies To Manage The Tarnished Plant Bug (Heteroptera: Miridae) In Cotton, Scott Hester Graham May 2016

Best Management Strategies To Manage The Tarnished Plant Bug (Heteroptera: Miridae) In Cotton, Scott Hester Graham

Theses and Dissertations

Experiments were conducted to determine the impact of combining multiple best management practices to manage the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), on cotton. The implementation of this program reduced the amount of insecticide applications needed, significantly increased both square retention during the three weeks of squaring, and yield in the Delta region. Another study was conducted to explore behavioral responses of tarnished plant bug nymphs to several classes of insecticides. There appeared to be both avoidance and attraction depending on insecticide class. The presence of an insecticide did not affect the fruiting structure tarnished plant bugs were …