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Full-Text Articles in Life Sciences

Impact Of Early-Season Postemergence Co-Applications Of Foliar And Residual Herbicides On Crop Injury, Growth, And Yield In 2,4-D- And Dicamba-Tolerant Cotton (Gossypium Hirsutum L.), Logan N. Vallee May 2024

Impact Of Early-Season Postemergence Co-Applications Of Foliar And Residual Herbicides On Crop Injury, Growth, And Yield In 2,4-D- And Dicamba-Tolerant Cotton (Gossypium Hirsutum L.), Logan N. Vallee

LSU Master's Theses

Studies were conducted in 2021 through 2023 at the LSU AgCenter Dean Lee Research and Extension Center near Alexandria, LA to determine the sensitivity of 2,4-D- or dicamba- tolerant cotton (Gossypium hirsutum L.) to an early season application of a Group 15 and foliar-only herbicides. Both studies were randomized complete block designs with a two-factorial arrangement of treatments with four replications. In the dicamba-tolerant cotton study, Factor A consisted of no foliar-herbicide, dicamba alone, glyphosate alone, or dicamba plus glyphosate. Factor B consisted of either no Group 15 residual herbicide, acetochlor, or S-metolachlor. In the 2,4-D- tolerant cotton …


Cover Cropping In Soybean-Corn Rotation System: Economic, Agronomic, And Soil Fertility Impact, Jose Rodolfo Mite Jun 2020

Cover Cropping In Soybean-Corn Rotation System: Economic, Agronomic, And Soil Fertility Impact, Jose Rodolfo Mite

LSU Doctoral Dissertations

Planting winter-annual cover crops prevent soil erosion, reduces water runoff, and improves soil structure and soil quality. This research was conducted from 2017 to 2019 to evaluate the nutrient turnover of different species of cover crops in soils under different row crop production systems in Northeast and Central Louisiana. In Northeast Louisiana (Site 1, 2, and 3), treatments (cover crops and no cover crop) were arranged in a strip trial with three replications. At the Ben Hur Research Station, the treatments included three planting dates (September, October, and November) with [7 kg ha-1 of phosphorus (P) and potassium (K)] …


Distinguishing Isolates Of Rotylenchulus Reniformis Endemic In Louisiana On The Basis Of Root-Associated Females And Egg Masses, Benjamin Mcinnes Nov 2017

Distinguishing Isolates Of Rotylenchulus Reniformis Endemic In Louisiana On The Basis Of Root-Associated Females And Egg Masses, Benjamin Mcinnes

LSU Master's Theses

The reniform nematode Rotylenchulus reniformis is a major pathogen of soybean and cotton in Louisiana. Previous studies have shown that populations of reniform nematode throughout the southern United States vary in reproduction and pathogenicity. Limited studies have been conducted to evaluate the reproduction and pathogenicity of populations of R. reniformis endemic in Louisiana. Studies with isolates of the nematode from eight cotton-producing parishes focused solely on reproduction of the root-associated infective and swollen female life stages with and without attached egg masses on the cotton genotypes MT2468 Ren3, M713 Ren5, and Stoneville 4946GLB2 and the soybean genotypes PI 548316, PI …


Impact Of Pre-Bloom Square Loss On Yield And Lint Quality In Louisiana Cotton Cropping Systems, Cory L. Cole Oct 2017

Impact Of Pre-Bloom Square Loss On Yield And Lint Quality In Louisiana Cotton Cropping Systems, Cory L. Cole

LSU Master's Theses

During the 2016 growing season, research was conducted at three locations in the state of Louisiana to evaluate the impact of pre-bloom square loss on cotton lint yield and fiber quality. Two cotton varieties, Phytogen 499 WRF and Phytogen 222 WRF were chosen up which to imitate early season square loss due to tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) and/or cotton fleahopper, Pseudatomoscelis seriatus (Reuter) feeding or unfavorable weather conditions. Thirty plants within each plot were selected and squares were counted. Squares were assigned numbers, and numbers were then randomized using a computerized number generator. To simulate intervals …


Determining The Influence Of Imidacloprid And Glufosinate Ammonium On The Population Dynamics Of Twospotted Spider Mite Populations In Louisiana Cotton, Sebe Anthony Brown Jan 2017

Determining The Influence Of Imidacloprid And Glufosinate Ammonium On The Population Dynamics Of Twospotted Spider Mite Populations In Louisiana Cotton, Sebe Anthony Brown

LSU Doctoral Dissertations

Twospotted spider mites, Tetranychus urticae, is an important agricultural pest of many field crops worldwide. This study investigated the impacts of imidacloprid seed treatments on populations of twospotted spider mites while also investigating if exogenous applications of jasmonic acid can offset any hormone modulating effects caused by seed treatments. Imidacloprid seed treatments significantly increased cumulative adult mite days in 2013 but not 2015 or 2016 in the field. Applications of 10 millimolar jasmonic acid did not reduce mite severity or injury in all field trials. Imidacloprid seed treatments significantly increased all spider mite life stages in the laboratory while applications …


An Evaluation Of The Impact Of The Adoption Of The Onboard Module Building Cotton Harvest System On The Economic Competitiveness Of Cotton Production In Louisiana, Natalia Estefania Latorre Jan 2014

An Evaluation Of The Impact Of The Adoption Of The Onboard Module Building Cotton Harvest System On The Economic Competitiveness Of Cotton Production In Louisiana, Natalia Estefania Latorre

LSU Master's Theses

Planted acreage of cotton in Louisiana has decreased over the past several years due to higher cotton variable production costs, stagnant cotton market prices, and higher grain yields and market prices for corn and soybeans. The general objective was to determine the economic impact of the adoption and use of an onboard module building cotton harvest system on the ability of the cotton enterprise to compete for planted acreage in the mixed crop farming areas of Louisiana. Specific research objectives included the estimated of comparative ownership and operating costs for the module building harvest systems relative to existing basket/module builder …


Quantifying Tarnished Plant Bug, Lygus Lineolaris (Palisot De Beauvois), Resistance To Acephate In Louisiana, Josh T. Copes Jan 2010

Quantifying Tarnished Plant Bug, Lygus Lineolaris (Palisot De Beauvois), Resistance To Acephate In Louisiana, Josh T. Copes

LSU Master's Theses

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is one of the most yield- limiting insect pests attacking cotton in the Mid-Southern region of the U.S. This pest is almost exclusively managed with chemical control strategies. The organophosphate insecticide, acephate, has been one of the most important insecticides recommended to control tarnished plant bugs. In recent years, reports of unsatisfactory acephate performance have become common and actual field rates have been increased to improve control. The objective of this study was to survey acephate susceptibility in Louisiana populations of tarnished plant bug using laboratory bioassays and evaluate acephate efficacy …


Effects Of Acephate On The Distribution Of Tarnished Plant Bugs Within The Cotton Plant Profile, Kyle Andrew Fontenot Jan 2009

Effects Of Acephate On The Distribution Of Tarnished Plant Bugs Within The Cotton Plant Profile, Kyle Andrew Fontenot

LSU Master's Theses

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is a primary pest of cotton in the mid-southern United States. Chemical control strategies are the primary integrated pest management tool used to manage this pest in cotton. A better understanding of tarnished plant bug behavior and distribution on cotton plants is needed to improve the scouting and monitoring protocols used to estimate population and crop injury levels needed to initiate treatments. This pest frequently re-infests fields after insecticide treatments. Sampling protocols should consider the sub-lethal effects of insecticides on migrating populations or on survivors that remain on insecticide-treated plants. Studies …


The Influence Of Morningglory (Ipomoea Lacunosa), Hemp Sesbania (Sesbania Exaltata), And Johnsongrass (Sorghum Halepense) On Reproduction Of Rotylenchulus Reniformis On Cotton Gossypium Hirsutum L. And Soybean Glycine Max. (L.) Merrill, Michael John Pontif Jan 2007

The Influence Of Morningglory (Ipomoea Lacunosa), Hemp Sesbania (Sesbania Exaltata), And Johnsongrass (Sorghum Halepense) On Reproduction Of Rotylenchulus Reniformis On Cotton Gossypium Hirsutum L. And Soybean Glycine Max. (L.) Merrill, Michael John Pontif

LSU Doctoral Dissertations

Microplot studies were conducted to evaluate the effects of cotton (LA. 887), soybean (Pioneer 96B21), and three endemic weed species, pitted morningglory (Ipomoea lacunosa), hemp sesbania (Sesbania exaltata), and johnsongrass (Sorghum halepense), on reproduction of the reniform nematode, (Rotylenchulus reniformis). Over two microplot trials the co-culture of cotton with any of the three weeds suppressed numbers of reniform nematode juveniles in soil. When grown singly, reniform nematode reproductive values after 60 days on cotton averaged 69.0, while those for morningglory, hemp sesbania, and johnsongrass averaged 42.0, 23.5, and 18.0, respectively. Reproductive values for cotton co-cultured with morningglory averaged 38.7. Those …


Evaluating Precision Agricultural Technologies In A Louisiana Cotton Insect Pest Management System, Joshua Heath Temple Jan 2007

Evaluating Precision Agricultural Technologies In A Louisiana Cotton Insect Pest Management System, Joshua Heath Temple

LSU Master's Theses

A variable rate pesticide application system was developed and tested during 2001 for an agricultural aircraft in Louisiana. Using technology available to the agricultural aviation industry, a variable rate prescription of insecticide was successfully applied to a cotton field in 2002. These studies compared the efficacy and value of spatially variable insecticide (SVI) applications based on yield maps to the producer standard, whole-field broadcast treatments. Insecticide prescriptions were created from historical yield and production data. Treatments included whole-field broadcast sprays, yield-based SVI sprays, and profit-based SVI sprays. Twenty-two SVI applications were made to test fields from 2002-2005 using two aircraft …


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 …


Bollworm (Lepidoptera: Noctuidae) Production From Alternate Host Crops And Their Contribution To A Non-Bollgard Cotton Refuge, Edward Ashley Peters Jan 2004

Bollworm (Lepidoptera: Noctuidae) Production From Alternate Host Crops And Their Contribution To A Non-Bollgard Cotton Refuge, Edward Ashley Peters

LSU Master's Theses

The bollworm’s, Helicoverpa zea (Boddie), inherent tolerance to the Bacillus thuringiensis toxin expressed in Bollgard® cotton and its ability to exploit numerous hosts has caused the Environmental Protection Agency to re-evalute the refuge component of the resistance management strategy. The goal of this project was to evaluate selected alternate host crops as supplemental non-cotton refuges for bollworm. The relative density, temporal occurrence, and life stage synchrony for bollworm larvae and adults was studied in Bollgard® cotton, Bollgard® cotton non-Bollgard® cotton, field corn, grain sorghum, and soybean. Native populations of bollworm larvae were monitored June to September during 2002 and 2003 …


Effect Of Cotton Aphids, Aphis Gossypii (Glover), On Cotton Plant Development And Yield Components, Robert Hankins Jones Jan 2004

Effect Of Cotton Aphids, Aphis Gossypii (Glover), On Cotton Plant Development And Yield Components, Robert Hankins Jones

LSU Master's Theses

The effect of cotton aphids, Aphis gossypii (Glover), on cotton plant development and yield was studied during 2000 and 2001. Tests were conducted at the Macon Ridge Station (Winnsboro, Louisiana) in 2000 and 2001, and at the Northeast Research Station (St. Joseph, Louisiana) in 2001. Tests were performed in irrigated and non-irrigated regimes using individual plant comparisons, micro-plots, and whole plots. In both years and at both locations, cotton aphid densities induced chlorosis, and a downward cupping of leaves during the infestation period. The insecticides, pymetrozine and thiamethoxam, were applied to control natural infestations of cotton aphids. Although pymetrozine and …


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 …


Bollworm (Lepidoptera: Noctuidae) Ecology On Genetically Engineered Bollgard And Bollgard Ii Cottons, Jeffrey Gore Jan 2002

Bollworm (Lepidoptera: Noctuidae) Ecology On Genetically Engineered Bollgard And Bollgard Ii Cottons, Jeffrey Gore

LSU Doctoral Dissertations

The ecology of bollworms, Helicoverpa zea (Boddie), on Bollgard and Bollgard II cottons, Gossypium hirsutum L., was studied in field and laboratory experiments. Neonate bollworm larvae were placed on selected components of cotton squares and flowers from non-Bollgard, Bollgard, and Bollgard II cotton varieties. Larval survival was higher on flower anthers and square anthers than on other floral parts for each cultivar. Bollworm survival was lowest on all Bollgard II floral structures. To evaluate larval behavior on Bollgard cotton, first instar bollworms were placed on terminals of non-flowering and flowering cotton plants. Larvae were recovered lower on Bollgard cotton than …