scholarly journals Effects of Plant Substrate, Insecticide, and Blood Meal Status on the Efficacy of Barrier Treatments Against Aedes albopictus

2021 ◽  
Vol 37 (1) ◽  
pp. 20-27
Author(s):  
Benjamin E. McMillan ◽  
Brandi L. Benedict ◽  
Carlyle C. Brewster ◽  
Nicola T. Gallagher ◽  
Sally L. Paulson
Keyword(s):  
Plant Species ◽  
Aedes Albopictus ◽  
Blood Meal ◽  
Significant Interaction ◽  
Sampling Period ◽  
Mortality Rates ◽  
Limited Impact ◽  
Effective Barrier ◽  
Lambda Cyhalothrin

ABSTRACT The effects of 3 plant species (Cornus florida [dogwood], rhododendron X ‘Chionoides' [rhododendron], and Ilex opaca [American holly]), 4 insecticide treatments (Demand® CS [lambda-cyhalothrin] at 6.25 ml[AI]/liter; Talstar® Professional [bifenthrin] at 7.81 ml[AI]/liter, and Suspend® Polyzone® [deltamethrin] at 11.72 ml[AI]/liter, and water), and 2 physiological states (blood-fed and unfed) were evaluated for knockdown (1 h) and mortality (24 h) against female Aedes albopictus over an 8-wk sampling period. Analyses determined that there was a significant interaction between the tested plant species and the insecticides evaluated. Significant differences were likewise observed between the insecticide treatments for unfed Ae. albopictus females, with Demand CS demonstrating the highest knockdown and mortality rates (from >90% to >10% at wk 8 and >95% to ∼50% at wk 8, respectively), followed by Talstar Professional (from >75% to <10% at wk 2 and >90% to <10% at wk 2, respectively) and Suspend Polyzone (from >20% to <10% at wk 8 and >25% to >50% at wk 8, respectively). All treatments were no longer significant for knockdown or mortality at the end of the 8-wk timeframe. Significant differences were also observed between insecticide treatments for blood-fed Ae. albopictus females; Demand CS showed high knockdown and mortality rates (from 100% to ∼50% at wk 8 and 100% to >60% at wk 8, respectively), Suspend Polyzone rates were similar to Demand CS (from >80% to ∼50% at wk 8 and ∼90% to >65% at wk 8, respectively), and both were followed by Talstar Professional (from 100% to <10% at wk 4 and 100% to <20% at wk 4, respectively). All tested pyrethroid sprays showed a significant increase in effectiveness against recently blood-fed Ae. albopictus females, as compared to the unfed females. These results suggest that Demand CS can be used as an effective barrier spray against Ae. albopictus adults due to the limited impact of target foliage, its long-term efficacy under environmental conditions, and its continued effectiveness regardless of the blood meal status of the target mosquito.

scholarly journals Effects of Plant Species, Insecticide, and Exposure Time On the Efficacy Of Barrier Treatments Against Aedes albopictus

2018 ◽  
Vol 34 (4) ◽  
pp. 281-290 ◽  
Author(s):  
Benjamin E. McMillan ◽  
Jake E. Bova ◽  
Carlyle C. Brewster ◽  
Nicola T. Gallagher ◽  
Sally L. Paulson
Keyword(s):  
Plant Species ◽  
Aedes Albopictus ◽  
Adult Mortality ◽  
Miscanthus Sinensis ◽  
Chemical Treatments ◽  
Residual Toxicity ◽  
Japanese Honeysuckle ◽  
Lambda Cyhalothrin ◽  
Significant Difference ◽  
Over Time

ABSTRACT The effect of 5 plant species (arborvitae [Thuja occidentalis], boxwood [Buxus sp., Japanese honeysuckle [Lonicera japonica], rhododendron [Rhododendron sp.], and zebra grass [Miscanthus sinensis]) and 2 rates of lambda-cyhalothrin (3.13 ml and 6.25 ml active ingredient [AI]/liter) on knockdown (1 h) and mortality (24 h) of adult female Aedes albopictus was evaluated over an 8-wk period. A significant difference in knockdown was observed between the 2 rates of lambda-cyhalothrin on the 5 plant species, with the highest proportion of knockdown observed on zebra grass and rhododendron treated at the higher rate. Although mortality was ≥60% and 85% on the 5 plant species at the low and high rates of lambda-cyhalothrin, respectively, a significant difference between the 2 rates was only observed on boxwood and Japanese honeysuckle (P < 0.0001). We also tested the residual toxicity of 3 barrier sprays (lambda-cyhalothrin, bifenthrin, and deltamethrin) and evaluated the efficacy of a short (5-min) exposure to the insecticides on knockdown and mortality of adults over time. Significantly higher knockdown was observed with lambda-cyhalothrin compared with bifenthrin and deltamethrin (P < 0.0001). Mean knockdown was ∼98%, 92%, and 20% for lambda-cyhalothrin, bifenthrin, and deltamethrin, respectively, at week 2, and ∼98%, 0%, and 44%, respectively, 8 wk after treatments were applied. Adult mortality from the 3 chemical treatments, however, remained above 90% throughout the study. Lastly, the trends in mean proportion of knockdown were similar for mosquitoes exposed for either 5 min or 24 h to the 3 chemicals. An overall decline in mean mortality over time, however, was observed for mosquitoes exposed for 5 min to the chemicals compared with mortality from the 24-h exposure. The results suggest that lambda-cyhalothrin can be an effective barrier spray treatment against Ae. albopictus adults because its efficacy is limited little by plant species, it has long residual toxicity, and it is effective following only 5 min of exposure.

Adulticide Resistance Status of Aedes albopictus (Diptera: Culicidae) in Sabah, Malaysia: A Statewide Assessment

2019 ◽  
Vol 56 (6) ◽  
pp. 1715-1725
Author(s):  
N M R Elia-Amira ◽  
C D Chen ◽  
V L Low ◽  
K W Lau ◽  
A Haziqah-Rashid ◽  
...  
Keyword(s):  
Mortality Rate ◽  
Correlation Analysis ◽  
Aedes Albopictus ◽  
Mortality Rates ◽  
The Other ◽  
Cross Resistance ◽  
Lambda Cyhalothrin ◽  
East Malaysia ◽  
Statewide Assessment ◽  
Susceptibility Status

Abstract Resistance status of Aedes albopictus (Diptera: Culicidae) collected from Sabah, East Malaysia, was evaluated against four major classes of adulticides, namely pyrethroid, carbamate, organochlorine, and organophosphate. Adult bioassays conforming to WHO standard protocols were conducted to assess knockdown and mortality rates of Ae. albopictus. Among tested pyrethroid adulticides, only cyfluthrin, lambda-cyaholthrin, and deltamethrin were able to inflict total knockdown. The other adulticide classes mostly failed to cause any knockdown; the highest knockdown rate was only 18.33% for propoxur. With regards to mortality rate, Ae. albopictus was unanimously susceptible toward all pyrethroids, dieldrin, and malathion, but exhibited resistance toward bendiocarb, propoxur, dichlorodiphenyltrichloroethane, and fenitrothion. Additionally, correlation analysis demonstrated cross-resistance between bendiocarb and propoxur, and malathion and propoxur. In conclusion, this study has disclosed that pyrethroids are still generally effective for Aedes control in Sabah, Malaysia. The susceptibility status of Ae. albopictus against pyrethroids in descending order was cyfluthrin > lambda-cyhalothrin > deltamethrin > etofenprox > permethrin.

scholarly journals Kalahari vegetation: veld condition trends and ecological status of species

Koedoe ◽  
1991 ◽  
Vol 34 (1) ◽  
Author(s):  
N. Van Rooyen ◽  
G.J. Bredenkamp ◽  
G.K. Theron
Keyword(s):  
Species Composition ◽  
Plant Species ◽  
National Park ◽  
Ecological Status ◽  
Grazing Intensity ◽  
Sampling Period ◽  
River Terrace ◽  
River Bed

Grazing intensity gradients were determined in the duneveld, river terrace and river bed habitats of the Kalahari Gemsbok National Park. Under increased grazing, a species composition characterised mostly by annual forbs and grasses results. In all three habitats the relatively heavily grazed areas were closest to the watering points, although this was less evident in the river terrace and river bed habitats. Monitoring degradation at a watering point over the long term, produced results similar to those observed from a single sampling period. The identification of grazing gradients within homogeneous habitats, is a prerequisite for the classification of plant species into different categories. The allocation of a species to a category is based on the changes in frequency along this grazing gradient and this approach is more acceptable than the classification of species commonly used. The use of terminology such as Decreasers and Increasers is discussed.

Adulticide Resistance Status of Aedes albopictus (Diptera: Culicidae) in Sarawak State, Malaysia

2021 ◽  
Author(s):  
Koon Weng Lau ◽  
Chee Dhang Chen ◽  
Van Lun Low ◽  
Han Lim Lee ◽  
Abdul Aziz Azidah ◽  
...  
Keyword(s):  
Aedes Albopictus ◽  
Mortality Rates ◽  
The Other ◽  
World Health ◽  
Cross Resistance ◽  
Lambda Cyhalothrin ◽  
The World ◽  
Resistance Patterns ◽  
Health Organization ◽  
Susceptibility And Resistance

Abstract Resistance status of Aedes albopictus (Skuse) from 13 districts in Sarawak State, Malaysia, was evaluated against four major classes of adulticides, namely organochlorine, organophosphate, carbamate, and pyrethroid. Adult bioassays were performed according to the World Health Organization (WHO) standard protocols to assess knockdown and mortality rates of Ae. albopictus. Among the tested pyrethroids, only cyfluthrin was able to exhibit complete knockdown. On the other hand, different susceptibility and resistance patterns were observed in other adulticides. As for mortality rates, the mosquitoes were susceptible to cyfluthrin and dieldrin but exhibited various susceptibilities to other tested adulticides. Cross-resistance was discovered within and between tested insecticide classes. Significant correlations were found within pyrethroid and carbamate classes (i.e., bendiocab and propoxur, P = 0.036; etofenprox and permethrin, P = 0.000; deltamethrin and lambda-cyhalothrin, P = 0.822; deltamethrin and permethrin, P = 0.042). Additionally, insecticides belonging to different groups were also found significantly correlated (i.e., malathion and deltamethin, P = 0.019; malathion and bendiocarb, P = 0.008; malathion and propoxur, P = 0.007; and bendiocarb and deltamethrin, P = 0.031). In conclusion, cyfluthrin was effective for Aedes albopictus control in Sarawak State and these data may assist local authorities to improve future vector control operations.

Using Long-Term Population Monitoring Data to Prioritize Conservation Action among Rare Plant Species

2019 ◽  
Vol 39 (2) ◽  
pp. 169 ◽  
Author(s):  
Holly L. Bernardo ◽  
Pati Vitt ◽  
Rachel Goad ◽  
Susanne Masi ◽  
Tiffany M. Knight
Keyword(s):  
Plant Species ◽  
Population Monitoring ◽  
Monitoring Data ◽  
Rare Plant ◽  
Conservation Action ◽  
Rare Plant Species

scholarly journals Long-Term Exposure to Fine and Coarse Particulate Matter and COVID-19 Incidence and Mortality Rate in Chile during 2020

2021 ◽  
Vol 18 (14) ◽  
pp. 7409
Author(s):  
Macarena Valdés Salgado ◽  
Pamela Smith ◽  
Mariel Opazo ◽  
Nicolás Huneeus
Keyword(s):  
Mortality Rate ◽  
Incidence Rate ◽  
Air Pollutants ◽  
Negative Binomial ◽  
Transport Model ◽  
Surface Concentration ◽  
Mortality Rates ◽  
Incidence And Mortality ◽  
Pm2.5 And Pm10

Background: Several countries have documented the relationship between long-term exposure to air pollutants and epidemiological indicators of the COVID-19 pandemic, such as incidence and mortality. This study aims to explore the association between air pollutants, such as PM2.5 and PM10, and the incidence and mortality rates of COVID-19 during 2020. Methods: The incidence and mortality rates were estimated using the COVID-19 cases and deaths from the Chilean Ministry of Science, and the population size was obtained from the Chilean Institute of Statistics. A chemistry transport model was used to estimate the annual mean surface concentration of PM2.5 and PM10 in a period before the current pandemic. Negative binomial regressions were used to associate the epidemiological information with pollutant concentrations while considering demographic and social confounders. Results: For each microgram per cubic meter, the incidence rate increased by 1.3% regarding PM2.5 and 0.9% regarding PM10. There was no statistically significant relationship between the COVID-19 mortality rate and PM2.5 or PM10. Conclusions: The adjusted regression models showed that the COVID-19 incidence rate was significantly associated with chronic exposure to PM2.5 and PM10, even after adjusting for other variables.

scholarly journals Comparing the Efficacy of Multidisciplinary Assessment and Treatment, or Acceptance and Commitment Therapy, with Treatment as Usual on Health Outcomes in Women on Long-Term Sick Leave—A Randomised Controlled Trial

2021 ◽  
Vol 18 (4) ◽  
pp. 1754
Author(s):  
Anna Finnes ◽  
Ingrid Anderzén ◽  
Ronnie Pingel ◽  
JoAnne Dahl ◽  
Linnea Molin ◽  
...  
Keyword(s):  
Sick Leave ◽  
Health Outcomes ◽  
Acceptance And Commitment Therapy ◽  
Significant Interaction ◽  
Treatment As Usual ◽  
Multidisciplinary Assessment ◽  
Commitment Therapy ◽  
Acceptance And Commitment ◽  
Assessment And Treatment

Background: Chronic pain and mental disorders are common reasons for long term sick leave. The study objective was to evaluate the efficacy of a multidisciplinary assessment and treatment program including acceptance and commitment therapy (TEAM) and stand-alone acceptance and commitment therapy (ACT), compared with treatment as usual (Control) on health outcomes in women on long-term sick leave. Method: Participants (n = 308), women of working age on long term sick leave due to musculoskeletal pain and/or common mental disorders, were randomized to TEAM (n = 102), ACT (n = 102) or Control (n = 104). Participants in the multidisciplinary assessment treatment program received ACT, but also medical assessment, occupational therapy and social counselling. The second intervention included ACT only. Health outcomes were assessed over 12 months using adjusted linear mixed models. The results showed significant interaction effects for both ACT and TEAM compared with Control in anxiety (ACT [p < 0.05]; TEAM [p < 0.001]), depression (ACT [p < 0.001]; TEAM [p < 0.001]) and general well-being (ACT [p < 0.05]; TEAM [p < 0.001]). For self-rated pain, there was a significant interaction effect in favour of ACT (p < 0.05), and for satisfaction with life in favour of TEAM (p < 0.001). Conclusion: Both ACT alone and multidisciplinary assessment and treatment including ACT were superior to treatment as usual in clinical outcomes.

scholarly journals Minor Treatments Can Play a Significant Role in Preserving Natural Habitats and Protected Species on the Shore of a Central European Lake

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1540
Author(s):  
Bence Fülöp ◽  
Bálint Pacsai ◽  
Judit Bódis
Keyword(s):  
Plant Species ◽  
Conservation Status ◽  
Active Management ◽  
Lake Balaton ◽  
Protected Species ◽  
Natural Habitats ◽  
Management Interventions ◽  
Natural Grasslands ◽  
Tourism Potential

Semi-natural grasslands were previously established through traditional land use and maintained by active management, but their extension nowadays is declining rapidly, particularly in areas that also have tourism potential. In parallel, the conservation value of the remaining areas is increasing. The shore of Lake Balaton is a particularly good example, as Lake Balaton is an area highly affected by tourism, yet there have been valuable habitats able to survive and provide refuge for many vulnerable, protected species. Fortunately, we have reliable information about the vegetation of the area from two decades ago. Comparing these data with our recent surveys we investigated the changes in habitats and the distribution of protected plant species in connection with the active conservation treatments such as grazing or cutting. Our results show that in areas where treatments are still ongoing, protected plant species are more likely to survive, or even other species can appear, which is in clear contrast with conditions experienced in abandoned areas, where at least seven protected species have disappeared. According to our results, minor, but appropriately chosen and well-executed management interventions, can help in the long-term maintenance of species-rich habitats and improving the conservation status of threatened species.

Sign in / Sign up

Export Citation Format

Share Document