Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MISSISSIPPI”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed2005

Profiles of pain in Mississippi: results from the Southern Pain Prevalence Study.

OBJECTIVES: To estimate the prevalence, intensity, frequency, and origins of pain in Mississippi residents and explore the social and cultural aspects of pain and pain management by measuring the impacts of pain on everyday life as well as respondents' beliefs and attitudes toward pain. STUDY DESIGN: Cross-sectional survey of Mississippi adults. SUMMARY OF BACKGROUND DATA: Data from previous population surveys and clinical studies indicate that pain is a pervasive part of everyday life. The prevalence, intensity and frequency of reported pain is substantial throughout these studies. The literature documents large and profound consequences of pain both for individual lives and for society. The data also suggest that beliefs and attitudes rooted in the social and cultural context of society may help explain how pain is managed or endured. METHODS: Telephone interviews with a representative sample (random digit dialing) of 604 Mississippi adults were conducted utilizing a computer-assisted telephone interviewing system. The cooperation rate was 94.8% (5.2 % refusal). The Code of Standards and Ethics for Survey Research rate was 67.4% and the maximum sampling error was +/- 4.0% (95% confidence interval). The Mississippi survey data represent a subset of the data obtained in the six-state Southern Pain Prevalence Study. RESULTS: The pain prevalence rate was estimated to be 37% of the overall Mississippi sample: 9% of the sample reported severe pain on at least a monthly basis; 16% reported moderate pain; and 12% reported mild pain. Among those reporting pain, a majority (52%) experienced pain on a daily basis. The most commonly reported origins of pain were back pain (49%), leg and knee pain (41%), and shoulder.and arm pain (20%). Respondents also reported that both moderate and severe pain had substantial negative impacts on multiple facets of everyday life, including interference with sleep (84%), recreational/leisure activities (78%), ability to work (68%), sexual relations (43%), and relationships with others (36%). Mental health impacts for respondents with moderate to severe pain on at least a monthly basis included increased feelings of anxiety (66%), self-reported depression (63%), and loneliness (46%). When responding to questions regarding beliefs and attitudes about pain and pain management, the majority of respondents (62%) considered pain to be a normal part of everyday life. Many respondents felt that medicine should be saved until the pain becomes worse (55%), and a substantial number of respondents felt that good patients do not complain about pain to their doctors (22%). CONCLUSIONS: This study expands the body of knowledge about the prevalence of pain in Mississippi, suggesting that approximately one-third of the state's adults are affected by pain on at least a monthly basis. Most of this pain is moderate to severe and quite frequent--occurring daily for the majority of pain sufferers. The study also illuminates social and cultural dimensions of pain, revealing that a) the presence of pain negatively affects almost every facet of life, from sleep and work to relationships, leisure activities, and mental health, and b) respondents attitudes and beliefs are often at variance with modern approaches to pain management. Knowledge gained could have critical implications for understanding patients and the treatment of pain.

Adolescent↗
PubMed2000

Nitrogen flux and sources in the Mississippi River Basin.

Nitrogen from the Mississippi River Basin is believed to be at least partly responsible for the large zone of oxygen-depleted water that develops in the Gulf of Mexico each summer. Historical data show that concentrations of nitrate in the Mississippi River and some of its tributaries have increased by factors of 2 to more than 5 since the early 1900s. We have used the historical streamflow and concentration data in regression models to estimate the annual flux of nitrogen (N) to the Gulf of Mexico and to determine where the nitrogen originates within the Mississippi Basin. Results show that for 1980-1996 the mean annual total N flux to the Gulf of Mexico was 1,568,000 t/year. The flux was approximately 61% nitrate as N, 37% organic N, and 2% ammonium as N. The flux of nitrate to the Gulf has approximately tripled in the last 30 years with most of the increase occurring between 1970 and 1983. The mean annual N flux has changed little since the early 1980s, but large year-to-year variations in N flux occur because of variations in precipitation. During wet years the N flux can increase by 50% or more due to flushing of nitrate that has accumulated in the soils and unsaturated zones in the basin. The principal source areas of N are basins in southern Minnesota, Iowa, Illinois, Indiana, and Ohio that drain agricultural land. Basins in this region yield 800 to more than 3100 kg total N/km2 per year to streams, several times the N yield of basins outside this region. Assuming conservative transport of N in the Mississippi River, streams draining Iowa and Illinois contribute on average approximately 35% of the total N discharged by the Mississippi River to the Gulf of Mexico. In years with high precipitation they can contribute a larger percentage.

Fresh Water↗
PubMed2000

Pesticides in the atmosphere of the Mississippi River Valley, part I--rain.

Weekly composite rainfall samples were collected in three paired urban and agricultural regions of the Midwestern United States and along the Mississippi River during April-September 1995. The paired sampling sites were located in Mississippi, Iowa, and Minnesota. A background site, removed from dense urban and agriculture areas, was located near Lake Superior in Michigan. Herbicides were the predominant type of pesticide detected at every site. Each sample was analyzed for 47 compounds and 23 of 26 herbicides, 13 of 18 insecticides, and three of three related transformation products were detected in one or more sample from each paired site. The detection frequency of herbicides and insecticides were nearly equivalent at the paired Iowa and Minnesota sites. In Mississippi, herbicides were detected more frequently at the agricultural site and insecticides were detected more frequently at the urban site. The highest total wet depositional amounts (microg pesticide/m2 per season) occurred at the agricultural sites in Mississippi (1980 microg/m2) and Iowa (490 microg/m2) and at the urban site in Iowa (696 microg/m2). Herbicides accounted for the majority of the wet depositional loading at the Iowa and Minnesota sites, but methyl parathion (1740 microg/m2) was the dominant compound contributing to the total loading at the agricultural site in Mississippi. Atrazine, CIAT (a transformation product of atrazine and propazine) and dacthal were detected most frequently (76, 53, and 53%, respectively) at the background site indicating their propensity for long-range atmospheric transport.

Air Pollutants↗
PubMed2000

Pesticides in the atmosphere of the Mississippi River Valley, part II--air.

Weekly composite air samples were collected from early April through to mid-September 1995 at three paired urban and agricultural sites along the Mississippi River region of the Midwestern United States. The paired sampling sites were located in Mississippi, Iowa, and Minnesota. A background site, removed from dense urban and agricultural areas, was located on the shore of Lake Superior in Michigan. Each sample was analyzed for 49 compounds; of these, 21 of 26 herbicides, 13 of 19 insecticides, and 4 of 4 related transformation products were detected during the study, with most pesticides detected in more than one sample. The maximum number of pesticides detected in an air sample was 18. Herbicides were the predominant type of pesticide detected at every site. Detection frequencies of most herbicides were similar at the urban and agricultural sites in Iowa and Minnesota. In Mississippi, herbicides generally were detected more frequently at the agricultural site. The insecticides chlorpyrifos, diazinon, and carbaryl, which are used in agricultural and non-agricultural settings, were detected more frequently in urban sites than agricultural sites in Mississippi and Iowa. Methyl parathion was detected in 70% of the samples from the Mississippi agricultural site and at the highest concentration (62 ng/m3 air) of any insecticide measured in the study. At the background site, dacthal (100%), atrazine (35%), cyanazine (22%), and the (primarily atrazine) triazine transformation products CIAT (35%) and CEAT (17%) were detected most frequently, suggesting their potential for long-range atmospheric transport.

Agriculture↗
PubMed1992

Avoiding the cost burden of newborn screening for the poor and uninsured: Mississippi's model.

The Mississippi State Department of Health Genetic Screening Program began in 1982 with hospitals joining the program on a volunteer basis. In 1985 legislation which mandated Newborn Screening provided the Mississippi Department of Health with the responsibility to promulgate rules and regulations establishing laboratory standards, to assure that each newborn was screened and to bill the hospital for each test. The Mississippi State Department of Health charges $12.75 per each newborn tested. This cost includes PKU, T4 (TSH if T4 is abnormal), and Hemoglobinopathy screening, as well as an administrative and follow-up charge. In order to compare the costs of existing systems which coordinate services related to newborn screening, a survey has been done. The confirmatory test for hemoglobinopathy screening will be performed in the Mississippi State Department of Health Laboratory beginning July 1, 1990. This will enable the Mississippi Genetic Screening Program to charge for patients who qualify for Medicaid.

Data Collection↗
PubMed2003

Cardiovascular risk factors among women in Mississippi in the 1990s.

OBJECTIVES: To identify the prevalence of cardiovascular disease risk factors among Mississippi women from 1991 to 1999, using data from the Behavior Risk Factor Surveillance Survey (BRFSS) and to examine the probability that certain risk factors would occur in certain groups of African American and white women in Mississippi. METHODS: We extracted self-reported data on 9690 women in Mississippi from the BRFSS for 1991 to 1999. We performed logistic regression analyses to examine the independent effects of age and race as relative risks for cardiovascular disease, controlling for socioeconomic status. RESULTS: Odds ratios for cigarette smoking for some African American women, for high blood pressure for some white women, and for diabetes in some white and African American women were significantly elevated. Prevalence data, however, showed that African American women had a higher prevalence of diabetes and overweight than white women did. CONCLUSION: The prevalence of overweight among Mississippi women seemed to increase as they aged. Decreasing obesity should be a major public health priority, as obesity's association with several chronic diseases is well documented and it is very prevalent among Mississippi women. Implementing programs to address unhealthy behaviors is essential for maintaining good health and thus should be strongly encouraged.

Adult↗
PubMed2004

A retrospective analysis of trace metals, C, N and diatom remnants in sediments from the Mississippi River delta shelf.

The development of oil and gas recovery offshore of the Mississippi River delta began in shallow water in the 1950s, expanded into deeper waters, and peaked in the 1990s. This area of the outer continental shelf (OCS) is the historical and present location of >90% of all US OCS oil and gas production and reserves. The juxtaposition of its 4000 producing platforms, recovering $10 billion yr(-1) of oil, gas and produced water in the same area where about 28% of the US fisheries catch (by weight) is made and near 40% of the US coastal wetlands, makes this an area worth monitoring for regional pollutant loading. This loading may come from several sources, including sources related to OCS development, but also from the Mississippi River watershed. In this context, any contaminant loading on this shelf may be neither detectable nor significant against a background of climatic or biological variability. We examined the sedimentary record for indicators of industrial byproducts from OCS oil and gas development and of industrial products entering via the Mississippi River, primarily using vanadium (V) and barium (Ba) concentrations normalized for aluminum (Al). Barium is primarily used in drilling muds in the form of barite, whereas V is an important strengthening component of metal alloys, including steel. The fluctuations in the accumulation of Ba, but not V, were coincidental with the presumed use of barite. The fluctuations in V concentration in the sediments were coincidental with the national consumption of V. Copper (Cu), cadmium (Cd) and zinc (Zn) concentrations in sediments fluctuate coincidentally with V, not Ba, thus indicating that the dominant source of these trace metals in offshore sediments were derived from riverine sources, and were not primarily from in situ industrial processes releasing them on the shelf. This is not to suggest that local site-specific contamination is not a significant management or health concern. The low oxygen (hypoxia; < or = 2 mg l(-1)) zone that consistently covers much of this continental shelf's bottom layer in summer is attributed to nitrate loading from the Mississippi River. Increased nitrogen loading from river to shelf stimulates diatom production whose loading to the bottom layer and subsequent metabolism results in oxygen being depleted faster than it is replaced. In the last two decades there has been an increased accumulation of organic matter in sediments near the mouth of the Mississippi River. This coupling between river water, surface water and bottom water has recently expanded westward of the Atchafalaya River delta towards the Texas coast. The accumulation of biogenic silica (BSi) and carbon in dated sediments is coincidental with variations in riverine nitrate flux, but not with either V or Ba accumulation rates. These analyses indicate that both OCS development and riverine sources exert strong influences on the sediment constituents offshore, and that these influences may be independent of one another.

Carbon↗
PubMed2002

Black carbon from the Mississippi River: quantities, sources, and potential implications for the global carbon cycle.

Black carbon (BC) may be a major component of riverine carbon exported to the ocean, but its flux from large rivers is unknown. Furthermore, the global distribution of BC between natural and anthropogenic sources remains uncertain. We have determined BC concentrations in suspended sediments of the Mississippi River, the 7th largest river in the world in terms of sediment and water discharge, during high flow and low flow in 1999. The 1999 annual flux of BC from the Mississippi River was 5 x 10(-4) petagrams (1 Pg = 10(15) g = 1 gigaton). We also applied a principal components analysis to particulate-phase high molecular weight polycyclic aromatic hydrocarbon isomer ratios in Mississippi River suspended sediments. In doing so, we determined that approximately 27% of the BC discharged from the Mississippi River in 1999 originated from fossil fuel combustion (coal and smelter-derived combustion), implicating fluvial BC as an important source of anthropogenic BC contamination into the ocean. Using our value for BC flux and the annual estimate for BC burial in ocean sediments, we calculate that, in 1999, the Mississippi River discharged approximately 5% of the BC buried annually in the ocean. These results have important implications, not only for the global carbon cycle but also for the fluvial discharge of particulate organic contaminants into the world's oceans.

Carbon↗
PubMed2004

High prevalence of food insecurity and hunger in households in the rural Lower Mississippi Delta.

CONTEXT: Residents of the Lower Mississippi Delta of Arkansas, Louisiana, and Mississippi are at risk for food insecurity since a high proportion of the population live in households with incomes below the poverty level and have reduced access to food and decreased availability of a variety of foods. However, the magnitude of the problem is unknown because presently only nationwide and state estimates of food insecurity are available. PURPOSE: This study was conducted by the Lower-Mississippi Delta Nutrition Intervention Research Consortium to determine the prevalence of household food insecurity, identify high-risk subgroups in the Lower Delta, and compare to national data. METHODS: A 2-stage stratified cluster sample representative of the population in 36 counties in the Lower Delta was selected using list-assisted random digit dialing telephone methodology. A cross-sectional telephone survey of 1662 households was conducted in 18 of the 36 counties using the US Food Security Survey Module. FINDINGS: Twenty-one percent of Lower Delta households were food insecure, double the 2000 nationwide rate of 10.5%. Within the Lower Delta, groups with the highest rates of food insecurity were households with income below $15,000, black households, and households with children. The prevalence of hunger in Delta households with white children was 3.2% and in households with black children was 11.0%, compared to nationwide estimates of 0.3% and 1.6%. CONCLUSIONS: The Lower Mississippi Delta is characterized by a high prevalence of food insecurity and hunger. Future efforts to identify the household and community determinants of food insecurity to reduce its high prevalence are indicated.

Adolescent↗
PubMed1994

Bovine immunodeficiency virus: incidence of infection in Mississippi dairy cattle.

Bovine immunodeficiency virus (BIV), a lentivirus, was originally derived from a Holstein cow with persistent lymphocytosis and severe wasting. The virus is known to occur sporadically throughout the United States and perhaps across the globe, but epidemiological data concerning the incidence of BIV are meager and the virus was previously unreported in Mississippi animals. This study examined the seroepidemiology of BIV infection from two Mississippi dairy herds (Coastal Plains and MSU). Serology revealed a 38% incidence of BIV infection in Coastal Plains animals and a 58% incidence in MSU animals. A cumulative BIV seroprevalence of 50% was found in the Mississippi animals, and BIV seroprevalence increased with increasing age of the animals. Peripheral blood leukocytes of age matched BIV seropositive and seronegative animals were enumerated to assess any effect of BIV infection on leukocyte populations. No significant differences were found in total leukocyte populations or leukocyte subpopulations between BIV seropositive or seronegative animals. These data indicate that BIV infection is prevalent in Mississippi animals, but the role of BIV in bovine disease remains unclear.

Age Factors↗
PubMed2006

Carbon isotopes and iodine concentrations in a Mississippi River delta core recording land use, sediment transport, and dam building in the river's drainage basin.

Sedimentary material from coastal and nearshore areas in the Mississippi Delta region are comprised of different organic carbon sources with diverse ages that require isotopic and elemental records for resolving the various sources of plant residues. Carbon isotopic ((13)C, (14)C) values were used to differentiate contributions from plants using the C3, C4, and/or CAM (crassulacean acid metabolism) carbon fixation pathways., and iodine concentrations indicated that wetland plant residues are a significant source of organic carbon in a sediment core from the Mississippi River delta region collected at a 60 m water depth. This sediment core had been extensively described in Oktay et al. [Oktay, S.D., Santschi, P.H., Moran, J.E., Sharma, P., 2000. The (129)Iodine Bomb Pulse Recorded in Mississippi River delta Sediments: Results from Isotopes of I, Pu, Cs, Pb, and C. Geochim. Cosmochim. Acta 64 (6), 989-996.] and significantly, includes unique features that had not previously been seen in the marine environment. These special features include a plutonium isotopic close-in fallout record that indicates a purely terrestrial source for these sediment particles and the elements associated with it, and a distinct iodine isotopic peak (as well as peaks for plutonium and cesium isotopes) that indicate little bioturbation in this core. Our carbon isotopic and iodine data can thus be compared to published records of changes in drainage basin land use, river hydrology, and hydrodynamic sorting of suspended particles to elucidate if these changes are reflected in nearshore sediments. This comparison suggests a significant contribution for organic carbon (OC) from C4 plants to these sediments during the 1950's to early 1960's. Relative older carbon isotopes, and episodically high iodine concentrations (up to 34 ppm) were observed during this time period that (1) indicate sediment deposition that is coincident with the times of major hydrological changes induced from dam and levee building in both the upper and lower reaches of the Mississippi River drainage basin, and (2) suggest episodic organic carbon deposition from wetland plant residues.

Carbon Isotopes↗
PubMed2000

Occurrence and load of selected herbicides and metabolites in the lower Mississippi River.

Analyses of water samples collected from the Mississippi River at Baton Rouge, Louisiana, during 1991-1997 indicate that hundreds of metric tons of herbicides and herbicide metabolites are being discharged annually to the Gulf of Mexico. Atrazine, metolachlor, and the ethane-sulfonic acid metabolite of alachlor (alachlor ESA) were the most frequently detected herbicides and, in general, were present in the largest concentrations. Almost 80% of the annual herbicide load to the Gulf of Mexico occurred during the growing season from May to August. The concentrations and loads of alachlor in the Mississippi River decreased dramatically after 1993 in response to decreased use in the basin. In contrast, the concentrations and loads of acetochlor increased after 1994, reflecting its role as a replacement for alachlor. The peak annual herbicide load occurred in 1993, when approximately 640 metric tons (t) of atrazine, 320 t of cyanazine, 215 t of metolachlor, 53 t of simazine, and 50 t of alachlor were discharged to the Gulf of Mexico. The annual loads of atrazine and cyanazine were generally 1-2% of the amount annually applied in the Mississippi River drainage basin; the annual loads of acetochlor, alachlor, and metolachlor were generally less than 1%. Despite a reduction in atrazine use, historical data do not indicate a long-term downward trend in the atrazine load to the Gulf of Mexico. Although a relation (r2 = 0.62) exists between the atrazine load and stream discharge during May to August, variations in herbicide use and rainfall patterns within subbasins can have a large effect on herbicide loads in the Mississippi River Basin and probably explain a large part of the annual variation in atrazine load to the Gulf of Mexico.

Acetamides↗
PubMed1998

Spinal cord injury incidence in Mississippi: a capture-recapture approach.

BACKGROUND: Many studies have investigated spinal cord injury incidence rates. Few, however, have adjusted for the underascertainment. The current study used the capture-recapture method to estimate the ascertainment-corrected spinal cord injury incidence rate in Mississippi. METHODS: Two sources were used for case ascertainment: Mississippi's spinal cord injury registry and hospital reports. The two-sample capture-recapture method was used to adjust for undercount. RESULTS: Two hundred one spinal cord injuries were reported to or found by the Mississippi State Department of Health in 1993, with a crude incidence rate of 7.8 per 100,000 population per year among hospital admissions and prehospital fatalities. Using the two-sample capture-recapture method, it is estimated that the incidence rate would be 9.3 per 100,000 population per year. CONCLUSION: Capture-recapture estimates suggest that Mississippi's spinal cord injury incidence rate is more than twice the national average.

Epidemiologic Methods↗
PubMed1975

Clinical and epidemiologic features of Rocky Mountain spotted fever in Mississippi, 1933-1973.

During the period 1933-1973, 169 cases of Rocky Mountain spotted fever (RMSF) were either reported by physicians or detected in a retrospective survey of hospitals and practicing physicians in Mississippi. The epidemiologic characteristics of 119 cases and the clinical features of 75 serologically confirmed cases are summarized in this communication and compared with other published reviews of RMSF. Although the percentage of reported fatal cases decreased overall since 1950, 9 of 49 reported cases (18%) in Mississippi were fatal during the period 1969-1972. The yearly number of reported cases of RMSF in Mississippi increased fourfold from 1970-1973. In the past 40 years, only 5 cases of RMSF have been reported from the Mississippi delta, a flat agricultural region that includes over one fourth of the total population of the state.

Adolescent↗
PubMed2005

Violence-related behaviors on school property among Mississippi Public High School students, 1993--2003.

Researchers examined trends and compared subgroup differences in violence-related behaviors on school property among Mississippi public high school students from 1993 to 2003. Findings are based on data from the Mississippi Youth Risk Behavior Surveillance System (YRBSS), a representative sample (N = 9,058) of Mississippi high school students. Males, non-Hispanic Whites, heavy smokers, and binge drinkers reported violence-related behaviors on school property more frequently than their counterparts. A statistically significant linear decrease occurred during 1993--2003 in the percent of students carrying a weapon (p < 0.0001) and having a physical fight (p < 0.0001). The percent of students threatened or injured with a weapon on school grounds did not decrease significantly (p = 0.2800). Violence-related behaviors were reported somewhat less frequently among 12th graders but overall, grade was not a statistically significant factor. Trends observed in Mississippi appear to be occurring throughout the United States and perhaps globally. Parents, school officials, and community administrators are committed to reducing violence-related behavior on school property. Although the decreases are encouraging, the percent of students who reported violence-related behaviors remains at a level that causes serious concern. Efforts must continue and perhaps increase to curb behaviors that may lead to school violence. Future studies should elucidate mechanisms associated with the self-reported decreasing behaviors so intervention programs can be properly focused.

Adolescent↗
PubMed1995

Identifying modifiable risk factors for rehospitalization: a case-control study of seriously mentally ill persons in Mississippi.

OBJECTIVE: The authors sought to identify risk factors for rehospitalization in a seriously mentally ill population, focusing on factors that have the potential to be modified through community-based interventions. METHOD: A case-control design was used in which 101 "case" subjects (recently readmitted psychiatric patients) and a comparison group of 101 subjects living in the community who had been previously hospitalized at the same time as the case subjects, but who in contrast had not been readmitted, were matched on gender, ethnicity, and length of time at risk for rehospitalization. The setting was the Mississippi public mental health system during the first 3 months of 1988, including Mississippi State Hospital and the 10 community mental health regions in its catchment area. The subjects were between the ages of 18 and 55 years, had had at least one previous Mississippi State Hospital admission, and had a primary chart diagnosis of schizophrenia; 197 informants, mostly family members, were also included in the study. Data were collected from structured interviews of subjects and informants, direct observation ratings of subjects, Mississippi State Hospital administrative records, and community mental health center administrative records. RESULTS: Medication noncompliance, comorbid alcohol abuse, and a high level of criticism of subjects by informants were associated with greater risk of rehospitalization, while types and extent of outpatient service use, access to care, quality of life, and demographic variables (other than ethnicity and gender) were not. CONCLUSIONS: These findings imply that interventions aimed at improving medication compliance, reducing alcohol abuse, and helping families cope with their mentally ill relatives could reduce the risk of hospitalization in this population.

Adolescent↗
PubMed1990

Rural health care issues in the Lower Mississippi Delta: an agenda for the year 2000.

The 214 counties bordering both sides of the Lower Mississippi Delta from Cape Girardeau, Missouri, to New Orleans, Louisiana, currently represent one of the four major poverty regions in the United States. Despite the location of five major medical centers, the Lower Mississippi Delta continues to lag behind the rest of the country in important health indices. This paper presents comparative data on infant mortality rates and health care availability between the Lower Mississippi Delta and the rest of the nation. It also contains comparative data on the rural Lower Mississippi Delta and the rest of the rural U.S. Further comparisons of European and African-American infant mortality rates reveal necessary directions and important realities for future health efforts. Commission research, gathered in public hearings from the Delta, reveals a pattern of interrelated development factors that also seriously affect health care in rural Delta counties.

Black or African American↗
PubMed2000

Seasonal changes in pyrethroid resistance in tarnished plant bug (Heteroptera: Miridae) populations during a three-year period in the delta area of Arkansas, Louisiana, and Mississippi.

Tarnished plant bugs, Lygus lineolaris (Palisot de Beauvois), were collected from weeds at 71 locations in the delta of Arkansas, Louisiana, and Mississippi and tested with a discriminating dose bioassay for pyrethroid resistance in the spring (April-May) and again at the same locations in the fall (September-October) in 1995-1997. Percentage of mortality in the discriminating dose bioassay declined significantly (pyrethroid-resistance increased) from spring to fall by an average 18.7, 21.3, and 21.7% in Arkansas, Louisiana, and Mississippi, respectively. Pyrethroid resistance declined significantly by 26.3% from the fall of 1995 to the spring of 1996 in Mississippi, but did not significantly decline in Arkansas (4.1%) and Louisiana (13.2%). Significant decreases in resistance occurred in all 3 states from the fall of 1996 to the spring of 1997 (17.1, 38.3, and 29.8% in Arkansas, Louisiana, and Mississippi, respectively). Plant bugs from 2 locations (Indianola, MS, and Wainwright, LA) had multiple insecticide resistance to a carbamate, 2 pyrethroid, and 4 organophosphorus insecticides. However, resistance to the organophosphate acephate in plant bugs from both locations was not significant. Possible causes for the significant increases and declines in resistance from season to season are discussed.

Animals↗