Insecticide Sprays Research Articles

Pelatihan Pembuatan Insektisida Herbal Minyak Sereh Bentuk Spray di RPTRA Jeruk Manis

The Real Work Lecture is one of the implementations of the Tridarma activities of higher education which includes community service activities. The theme of the activity is chosen based on the needs of the community. Cases of Dengue Hemorrhagic Fever (DHF) in Jakarta are still high, so prevention is carried out, one of which is by using simple and environmentally friendly herbal insecticides. This training activity was carried out to increase the knowledge and skills of the community about herbal insecticides. The activity begins with a pretest, delivery of material, training and ends with a posttest. The activity was attended by 20 representatives elected by the Kelurahan. Based on the results of the service, it was found that there was an increase in participants' knowledge about herbal insecticides as indicated by an increase in pretest to posttest scores, from 40% to 95%. The product after the training is in the form of herbal insecticide spray preparations that can be used by participants, and can be remade for use as home products.

Ecoepidemiological Model and Optimal Control Analysis of Tomato Yellow Leaf Curl Virus Disease in Tomato Plant

The purpose of this study is to analyze the impact of control strategies, namely, insecticide spray, roguing of a diseased tomato plant, and protective netting to protect tomato plant from tomato yellow leaf curl virus disease (TYLCVD). For this, we formulate and analyze a simple deterministic model for the transmission dynamics of TYLCVD that incorporates these control strategies. We initially take into account the constant control case, we calculate the basic reproduction number, and we investigate the existence and stability of the disease-free and endemic equilibria. We use the Kamgang-Sallet stability to ensure that the disease-free equilibrium point is globally asymptotically stable when the reproduction number R 0 is less than one. This indicates that TYLCVD dies out independent of the initial size of the tomato population. For R 0 < 1 , the disease-free equilibrium becomes unstable, and the endemic equilibrium is globally asymptotically stable. This indicates that TYLCVD propagates. In the nonconstant control case, we use Pontryagin’s maximum principle to derive the necessary conditions for the optimal control of the disease. Our findings show that all the combined efforts of two out of three strategies can significantly reduce the power of infectivity of the disease except the combination of the use of insecticide spray and rouging infected tomato plants. Besides our numerical simulations show, the implementation of the combination of roguing diseased plants and protective netting has a similar effect in minimizing or eliminating TYLCV as the use of all strategies. Hence, as resources are always in scarce, we recommend policymakers to adapt the combination of the use of roguing diseased tomato plants and protective netting to eradicate the disease.

A mathematical model for Chagas disease transmission with neighboring villages

Chagas disease has been the target of widespread control programs, primarily through residual insecticide treatments. However, in some regions like the Gran Chaco, these efforts have failed to sufficiently curb the disease. Vector reinfestation into homes and vector resistance to insecticides are possible causes of the control failure. This work proposes a mathematical model for the dynamics of Chagas disease in neighboring rural villages of the Gran Chaco region, incorporating human travel between the villages, passive vector migration, and insecticide resistance. Computational simulations across a wide variety of scenarios are presented. The simulations reveal that the effects of human travel and passive vector migration are secondary and unlikely to play a significant role in the overall dynamics, including the number of human infections. The numerical results also show that insecticide resistance causes a notable increase in infections and is an especially important source of reinfestation when spraying stops. The results suggest that control strategies related to migration and travel between the villages are unlikely to yield meaningful benefit and should instead focus on other reinfestation sources like domestic foci that survive insecticide spraying or sylvatic foci.

Causes of honeybee colony decline in south Ethiopia

The purpose of this study was to identify the major causes of colony decline in the Gedeo Zone, South Ethiopia. Three districts, namely, Yirga Cheffe, Wonago, and Dilla Zuria, were purposefully selected based on beekeeping potential. A cross-sectional survey was conducted to collect data from 135 beekeepers and 15 key informants using a semi-structured questionnaire, focus group discussion, and personal observation of apiary sites. The results revealed two main causes of colony declines in the Gedeo zone: colony management-related factors and natural factors. Seventy percent of beekeepers lack the practical skills to perform hive inspection; 47% do not feed their colonies; 45% spray pesticides and insecticides near their apiaries; and 82% fail to control swarming. As a result, 87% of sampled beekeepers have experienced frequent colony absconding. The trends of colony decline showed an increase from 2008 to 2020 in the highlands and from 2008 to 2017 in the midlands and lowlands, respectively. The number of households facing colony declines increased in all agro-ecologies from 2008 to 2020. Pests and predators, like wax moths, and small hive beetles were take the first rank followed by ants, the inherent behavior of honeybees, a shortage of flora, and the presence of poisonous plants were the top five challenges among natural factors, respectively. Therefore, we strongly recommend educating beekeepers on scientific methods of colony management and planting bee flora. Laboratory diagnostics are required to identify bee diseases.

PxRdl2 dsRNA increased the insecticidal activities of GABAR-targeting compounds against Plutella xylostella

The utilization of RNA interference (RNAi) for pest management has garnered global interest. The bioassay results suggested the knockout of the PxRdl2 gene significantly increased the insecticidal activities of the γ-aminobutyric acid receptor (GABAR)-targeting compounds (fipronil, two pyrazoloquinazolines, and two isoxazolines), thereby presenting a viable target gene for RNAi-mediated pest control. Consequently, we suggest enhancing the insecticidal activities of GABAR-targeting compounds by knockdown the transcript level of PxRdl2. Furthermore, PxRdl2 dsRNA was expressed in HT115 Escherichia coli to reduce costs and protect dsRNA against degradation. In comparison to in vitro synthesized dsRNA, the recombinant bacteria (ds-B) exhibited superior interference efficiency and greater stability when exposed to UV irradiation. Collectively, our results provide a strategy for insecticide spray that combines synergistically with insecticidal activities by suppressing PxRdl2 using ds-B and may be beneficial for reducing the usage of insecticide and slowing pest resistance.

Temporal and spatial factors influencing Systena frontalis (Coleoptera: Chrysomelidae) behavior in Virginia nurseries.

Ornamental plant production in eastern Virginia nurseries have been greatly impacted by Systena frontalis (F.), also known as the red-headed flea beetle. With the advent of S. frontalis as a prevalent pest in the past 2 decades, baseline phenology and behavior are currently understudied within Virginia nurseries. This pest is costly to control due to insecticide expenses and loss of saleable plants. In 2021 and 2022, populations of this insect were monitored at 2 commercial nurseries in eastern Virginia in order to better understand their temporal and spatial population dynamics. Patterns that emerged indicated S. frontalis could have up to 3 generations in eastern Virginia, with peaks of adult abundance in June, late July, and late August to early September. Phenylethyl alcohol was tested as an adult attractant lure, but it was found to be ineffective under nursery conditions. Diel monitoring demonstrated these adults were most active from 1100 to 1500 h. Severity of defoliation at the leaf level increased linearly with increased density of adults, where 5 individuals defoliated up to 4% of any Hydrangea paniculata cv. 'Limelight' leaf in 1 wk under greenhouse conditions. Timing of scouting and insecticide sprays according to the adult activity peaks of the day and across the season may allow reduction in overall insecticide usage.

Sero-prevalence of visceral leishmaniasis and its associated factors among asymptomatic individuals visiting Denan health center, southeastern Ethiopia

BackgroundIn the Somali region of Ethiopia, visceral leishmaniasis (VL) is a public health concern. However, VL epidemiology and sand fly vectors have not been well studied in various areas of the regional state, including Denan district. Therefore, this study was conducted to determine the sero-prevalence, associated factors, and distribution of sand fly vectors of VL in Denan district, south-eastern Ethiopia.MethodsA facility-based cross-sectional study was conducted from April to September 2021 among VL patients with classic signs and symptoms visiting Denan Health Center in south-eastern Ethiopia. Using a convenience sampling method, 187 blood samples were collected from individuals who visited Denan Health Center during the study period. Blood samples were subjected to Direct Agglutination Test for the detection of antibodies to VL. A pre-tested structured questionnaire was also used to gather information on risk factors and other characteristics of knowledge and attitude assessment. Sand flies were also collected from indoor, peri-domestic, mixed forest, and termite mounds using light and sticky traps to determine the fauna and abundance.ResultsThe overall sero-prevalence rate was 9.63% (18/187). The sero-prevalence was significantly associated with outdoor sleeping (OR = 2.82), the presence of damp floors (OR = 7.76), and sleeping outdoor near animals (OR = 3.22). Around 53.48% of the study participants had previously heard about VL. Study participants practiced different VL control methods, including bed nets (42%), insecticide spraying (32%), smoking plant parts (14%), and environmental cleaning (8%). In total, 823 sand fly specimens, comprising 12 species in two genera (Phlebotomus and Sergentomyia), were trapped and identified. The most abundant species was Sergentomyia clydei (50.18%), followed by Phlebotomus orientalis (11.42%). Also, a higher proportion of P. orientalis was found in termite mounds (65.43%), followed by mixed forest (37.8%) and peri-domestic (20.83%) habitats.ConclusionThe study demonstrated a 9.63% sero-positivity of VL and a remarkable gap in knowledge, attitude, and practices towards VL. P. orientalis was also detected, which could be a probable vector in this area. Thus, public education should be prioritized to improve the community’s awareness of VL and its public health impact. In addition, detailed epidemiological and entomological studies are recommended.

Insecticide application using an unmanned aerial vehicle for Diaphorina citri control in citrus orchards

AbstractThe use of unmanned aerial vehicles (UAVs) combined with other methods to spray insecticides may be a useful technique for controlling Diaphorina citri Kuwayama (Hemiptera: Psyllidae) and consequently managing Huanglongbing. Therefore, this study was conducted to assess the efficacy of insecticide application using a UAV for D. citri control in citrus orchards of 1, 4 and 12 years old. In addition, spray deposition was assessed using copper as a marker. Seedlings of sweet orange were attached on the inner canopy and on the outer canopy of citrus trees before spraying insecticide or copper. An additional experiment was performed to assess the effect of 6 and 10 m spray swaths in the 4‐year‐old orchard. Ten adult psyllids were confined to each sprayed seedling. Untreated seedlings were used as a control. The first psyllid confinement was performed 4 h after spraying insecticide. The second, third and fourth confinements were performed 7, 14 and 21 days, respectively, after spraying. In general, insecticide application using a UAV resulted in psyllid mortality higher than 80% after the first and second confinements, regardless of the orchard age and seedling position on the citrus tree (inner or outer). There were no significant differences in D. citri mortality between the spray swaths assessed. Spray deposition on leaves was higher in the outer canopy than in the inner canopy of citrus trees. This study demonstrated, for the first time, the efficacy of insecticide application using a UAV for D. citri control in citrus orchards of different ages. These results broaden the prevailing perspectives on the use of UAVs as complements to ground spraying for psyllid management.

Managing the Use of Insecticides in Agricultural Fields: A Modeling Study

At present time, sustainable crop production is of prime importance due to the expansion of human population and diminishing cultivable land. Insects attack the plants’ roots, blooms and leaves and lessen the agricultural production across the globe. In this research work, we propose a nonlinear mathematical model to manage the spray of insecticides to control insect population and increase crop production. In the model formulation, we consider that the spraying of insecticides is attributed to both the density of insects and loss in crop production. This study identifies the range of spraying rate of insecticides at which the model system shows bistability behavior and its threshold value after which system stabilizes to the equilibrium with higher crop production. Further, we have also demonstrated that the model undergoes transcritical, saddle-node, Hopf, and Bogdanov–Takens bifurcations. The extensive numerical simulation is performed to validate the analytical findings.

Ivermectin as a novel malaria control tool: Getting ahead of the resistance curse

Reduction in malaria clinical cases is strongly dependent on the ability to prevent Anopheles infectious bites. Vector control strategies using long-lasting insecticidal nets and indoor residual spraying with insecticides have contributed to significantly reduce the incidence of malaria in many endemic countries, especially in the Sub-Saharan region. However, global progress in reducing malaria cases has plateaued since 2015 mostly due to the increased insecticide resistance and behavioral changes in Anopheles vectors. Additional control strategies are thus required to further reduce the burden of malaria and contain the spread of resistant and invasive Anopheles vectors. The use of endectocides such as ivermectin as an additional malaria control tool is now receiving increased attention, driven by its different mode of action compared to insecticides used so far and its excellent safety record for humans. In this opinion article, we discuss the advantages and disadvantages of using ivermectin for malaria control with a focus on the risk of selecting ivermectin resistance in malaria vectors. We also highlight the importance of understanding how ivermectin resistance could develop in mosquitoes and what its underlying mechanisms and associated molecular markers are, and propose a research agenda to manage this phenomenon.

Tea green leafhopper-induced synomone attracts the egg parasitoids, mymarids to suppress the leafhopper.

The tea green leafhopper, Empoasca flavescens is the most important pest of tea plants in China. Mymarid attractants based on herbivore-induced plant volatiles (HIPVs) from leafhopper feeding and oviposition-induced plant volatiles (OIPVs) were formulated and tested as a novel pest control agent against the leafhopper in tea plantations. Results showed that two mymarid species, Stethynium empoascae and Schizophragma parvula, had a reducing effect on leafhopper populations. The HIPVs and OIPVs were identified and bioassayed to screen the key synomones showing strong attraction to the mymarids. They were formulated into different blends, of which Field Attractant 1, comprising linalool, methyl salicylate, (E)-2-hexenal, perillen and α-farnesene at ratio of 1:2:3:58:146 (20 mg/lure), showed the strongest attraction to the mymarids. In field trials with the attractant, the average parasitism rate (60.46 ± 23.71%) of tea leafhoppers by the two mymarids in the attractant-baited area was significantly higher than that (42.85 ± 19.24%) in the CK area. Also, the average leafhopper density (46 ± 30 per 80 tea shoots) in the attractant-baited area was significantly lower than that (110 ± 70 per 80 tea shoots) in the CK area. This study showed that a synthetic blend of key volatiles from HIPVs and OIPVs at an optimal ratio can be formulated into an attractant with the potential to attract and retain wild mymarid populations to suppress leafhopper populations in infested tea plantations, so as to reduce or avoid the spraying of insecticides. © 2023 Society of Chemical Industry.

Associations of urinary phthalate metabolites with household environments among mothers and their preschool-age children

Phthalates have become a matter of public health concern due to their extensive use worldwide and negative health effects. The evaluation of potential sources of phthalate exposure is crucial to design prevention strategies, especially for vulnerable populations. This study included 528 mother-child pairs in the Taiwan Mother Infant Cohort Study who were followed up at ages 3–6 years between 2016 and 2020. Each mother was interviewed by using a structured questionnaire containing questions on demographic characteristics and household environment factors, such as the use of plastic food packaging, residential visible mold, insecticide sprays, and electric mosquito repellents. Eleven phthalate metabolites were analyzed in urine samples simultaneously collected from the mother-child pairs. The phthalate metabolite urinary concentrations were higher among the children than among their mothers, except those of mono-ethyl phthalate (MEP) and mono-2-ethylhexyl phthalate (MEHP). Multiple linear regression analyses showed that urine samples collected during the summer showed higher concentrations of phthalate metabolites than those collected during the winter. Family income levels had negative associations with the concentrations of MnBP and metabolites of di-2-ethylhexyl phthalate (DEHP) in children. The use of plastic food packaging was positively associated with mono-n-butyl phthalate (MnBP) and metabolites of DEHP in mothers. Residential visible mold or mold stains were significantly associated with higher MnBP and DEHP metabolite concentrations in children. The use of insecticide sprays was positively associated with MnBP concentrations in children. Significant associations between household environmental factors and phthalate exposure were mostly found in children, potentially indicating different exposure pathways between mothers and their children. Findings from this study provide additional information for the design of prevention strategies to protect the health of children and women.

Influence of Heliothinae (Lepidoptera: Noctuidae) pests on cotton yield components across a range of planting dates in the southeastern USA

Because of H. zea resistance to Bt toxins, there is renewed interest in cotton IPM, including adjusting planting date. Later planted crops often receive more damage or support larger populations of Heliothinae pests, but this has not been well-documented in cotton. We explored the effects of planting date relative to Heliothinae pests in cotton across various planting windows in the southeastern USA during 2020 and 2021. In-season injury, plant mapping, box mapping, and yield were assessed. In 2021, these planting dates were split with a protective insecticide. Peak boll injury by Heliothinae larvae was not different by planting date and insecticide sprays were usually effective to minimize injury. In general, there were more bolls in position one. Boll retention was usually similar across positions, but was sometimes higher in the lower positions. Bolls that contributed the most to yield tended to be in position one or monopodia bolls, and the yield contribution tended to decrease as boll position increased. As planting date progressed, the highest percent contribution to yield tended to be on lower nodes in the plant. Yields tended to be higher in the early and middle planting dates and were higher in insecticide sprayed plots when the economic threshold was exceeded. We found clear evidence for plant compensation from H. zea feeding in one trial. Planting date relative to Heliothinae pressure level was negligible, given the plant's ability to compensate and the extended window reproductive tissue was available in earlier planting dates relative to later planting dates.

Association between maternal use of spray formulations and offspring urological anomalies: The Japan Environment and Children's Study.

Concerns exist regarding the effects of maternal inhalation of household products on fetal health. This study aimed to clarify the impact of maternal exposure to household products, including spray formulations, on urological anomalies in offspring up to the age of 1 year. This study included data from 84 237 children from the Japan Environment and Children's Study, an ongoing nationwide cohort study. Using maternal self-report questionnaires, information on the use of organic solvents, waterproof sprays, insect-repellent sprays, insecticide sprays, and herbicides from implantation until the second or third trimester of pregnancy and data on urological anomalies were collected 1 year after delivery. Urological anomalies occurred in 799 infants. Multivariate logistic regression analysis adjusted for maternal age, pregnancy body mass index, gestational diabetes, pre-existing maternal kidney disease, and preterm birth revealed no association between maternal exposure to organic solvents and the prevalence of offspring urological anomalies. Nevertheless, we observed significant associations between waterproof spray use during pregnancy and urological anomalies in boys (odds ratio [OR]: 1.28, 95% confidence interval [CI]: 1.03-1.59) and between the use of insecticide spray during pregnancy and urological anomalies in girls (OR: 1.48, 95% CI: 0.98-2.22). Sub-analysis revealed significant associations between waterproof spray use during pregnancy and vesicoureteral reflux in boys (OR: 2.14, 95% CI: 1.02-4.49) and between the use of insecticide spray during pregnancy and hydronephrosis in girls (OR: 2.23, 95% CI: 1.11-4.47). Spray formulation use during pregnancy might increase the risk of urological anomalies in the offspring.

Comparative efficacy trials with alcohol added d-phenothrin formulations against Aedes aegypti under open-field condition.

Evaporation inhibition of water-based space spray insecticides is necessary to prevent the drifting away of fog droplets and the release of insecticidal actives and to prolong suspension time. To address this problem, hygroscopic alcohols, namely propylene glycol and glycerol, were included as adjuvants in water-based d-phenothrin formulations. The performances of glycerol-added formulation (D1) and propylene glycol-added formulation (D2) in terms of droplet size and efficacy against larvae, pupae and adult Aedes aegypti in an open-field environment were examined and compared to the performance of a formulation without adjuvant (negative control). No significant difference in droplet size was observed between the formulations and fogging methods. The efficacy of cold fogs was significantly higher than thermal fogs for all formulations. D2 was found to be most effective against adult Ae. aegypti, followed by D1 and the negative control. D1 and D2 provided complete knockdown and mortality in adult Ae. aegypti at 10 and 25 m for cold and thermal fogging, respectively. However, all d-phenothrin formulations possessed minimal efficacy on immature Ae. aegypti. The incorporation of non-toxic alcohols as adjuvants in water-based space spray insecticides increased efficacy against adult Ae. aegypti, a major vector for dengue. Propylene glycol was discovered to induce higher adulticidal efficacy than glycerol. © 2023 Society of Chemical Industry.

Traits-mediated responses of caterpillar communities to spongy moth outbreaks and subsequent tebufenozide treatments.

Outbreaks of the spongy moth Lymantria dispar can have devastating impacts on forest resources and ecosystems. Lepidoptera-specific insecticides, such as Bacillus thuringiensis var. kurstaki (BTK) and tebufenozide, are often deployed to prevent heavy defoliation of the forest canopy. While it has been suggested that using BTK poses less risk to non-target Lepidoptera than leaving an outbreak untreated, in situ testing of this assumption has been impeded by methodological challenges. The trade-offs between insecticide use and outbreaks have yet to be addressed for tebufenozide, which is believed to have stronger side effects than BTK. We investigated the short-term trade-offs between tebufenozide treatments and no-action strategies for the non-target herbivore community in forest canopies. Over three years, Lepidoptera and Symphyta larvae were sampled by canopy fogging in 48 oak stands in southeast Germany during and after a spongy moth outbreak. Half of the sites were treated with tebufenozide and changes in canopy cover were monitored. We contrasted the impacts of tebufenozide and defoliator outbreaks on the abundance, diversity, and functional structure of chewing herbivore communities. Tebufenozide treatments strongly reduced Lepidoptera up to six weeks after spraying. Populations gradually converged back to control levels after two years. Shelter-building species dominated caterpillar assemblages in treated plots in the post-spray weeks while flight-dimorphic species were slow to recover and remained underrepresented in treated stands two years post-treatment. Spongy moth outbreaks had minor effects on leaf chewer communities. Summer Lepidoptera decreased only when severe defoliation occurred, whereas Symphyta declined one year after defoliation. Polyphagous species with only partial host plant overlap with the spongy moth were absent from heavily defoliated sites, suggesting greater sensitivity of generalists to defoliation-induced plant responses. These results demonstrate that both tebufenozide treatments and spongy moth outbreaks alter canopy herbivore communities. Tebufenozide had a stronger and longer lasting impact, but it was restricted to Lepidoptera, whereas the outbreak affected both Lepidoptera and Symphyta. These results are tied to the fact that only half of the outbreak sites experienced severe defoliation. This highlights the limited accuracy of current defoliation forecast methods, which are used as the basis for the decision to spray insecticides.

Detecting common coccinellids found in sorghum using deep learning models

Increased global production of sorghum has the potential to meet many of the demands of a growing human population. Developing automation technologies for field scouting is crucial for long-term and low-cost production. Since 2013, sugarcane aphid (SCA) Melanaphis sacchari (Zehntner) has become an important economic pest causing significant yield loss across the sorghum production region in the United States. Adequate management of SCA depends on costly field scouting to determine pest presence and economic threshold levels to spray insecticides. However, with the impact of insecticides on natural enemies, there is an urgent need to develop automated-detection technologies for their conservation. Natural enemies play a crucial role in the management of SCA populations. These insects, primary coccinellids, prey on SCA and help to reduce unnecessary insecticide applications. Although these insects help regulate SCA populations, the detection and classification of these insects is time-consuming and inefficient in lower value crops like sorghum during field scouting. Advanced deep learning software provides a means to perform laborious automatic agricultural tasks, including detection and classification of insects. However, deep learning models for coccinellids in sorghum have not been developed. Therefore, our objective was to develop and train machine learning models to detect coccinellids commonly found in sorghum and classify them according to their genera, species, and subfamily level. We trained a two-stage object detection model, specifically, Faster Region-based Convolutional Neural Network (Faster R-CNN) with the Feature Pyramid Network (FPN) and also one-stage detection models in the YOLO (You Only Look Once) family (YOLOv5 and YOLOv7) to detect and classify seven coccinellids commonly found in sorghum (i.e., Coccinella septempunctata, Coleomegilla maculata, Cycloneda sanguinea, Harmonia axyridis, Hippodamia convergens, Olla v-nigrum, Scymninae). We used images extracted from the iNaturalist project to perform training and evaluation of the Faster R-CNN-FPN and YOLOv5 and YOLOv7 models. iNaturalist is an imagery web server used to publish citizen’s observations of images pertaining to living organisms. Experimental evaluation using standard object detection metrics, such as average precision (AP), AP@0.50, etc., has shown that the YOLOv7 model performs the best on the coccinellid images with an AP@0.50 as high as 97.3, and AP as high as 74.6. Our research contributes automated deep learning software to the area of integrated pest management, making it easier to detect natural enemies in sorghum.

Survey, Detection, Characterization of Papaya Ringspot Virus from Southern India and Management of Papaya Ringspot Disease.

Papaya ringspot virus (PRSV) is a significant threat to global papaya cultivation, causing ringspot disease, and it belongs to the species Papaya ringspot virus, genus Potyvirus, and family Potyviridae. This study aimed to assess the occurrence and severity of papaya ringspot disease (PRSD) in major papaya-growing districts of Karnataka, India, from 2019 to 2021. The incidence of disease in the surveyed districts ranged from 50.5 to 100.0 percent, exhibiting typical PRSV symptoms. 74 PRSV infected samples were tested using specific primers in RT-PCR, confirming the presence of the virus. The complete genome sequence of a representative isolate (PRSV-BGK: OL677454) was determined, showing the highest nucleotide identity (nt) (95.8%) with the PRSV-HYD (KP743981) isolate from Telangana, India. It also shared an amino acid (aa) identity (96.5%) with the PRSV-Pune VC (MF405299) isolate from Maharashtra, India. Based on phylogenetic and species demarcation criteria, the PRSV-BGK isolate was considered a variant of the reported species and designated as PRSV-[IN:Kar:Bgk:Pap:21]. Furthermore, recombination analysis revealed four unique recombination breakpoint events in the genomic region, except for the region from HC-Pro to VPg, which is highly conserved. Interestingly, more recombination events were detected within the first 1710 nt, suggesting that the 5' UTR and P1 regions play an essential role in shaping the PRSV genome. To manage PRSD, a field experiment was conducted over two seasons, testing various treatments, including insecticides, biorationals, and a seaweed extract with micronutrients, alone or in combination. The best treatment involved eight sprays of insecticides and micronutrients at 30-day intervals, resulting in no PRSD incidence up to 180 days after transplanting (DAT). This treatment also exhibited superior growth, yield, and yield parameters, with the highest cost-benefit ratio (1:3.54) and net return. Furthermore, a module comprising 12 sprays of insecticides and micronutrients at 20-day intervals proved to be the most effective in reducing disease incidence and enhancing plant growth, flowering, and fruiting attributes, resulting in a maximized yield of 192.56 t/ha.

Measuring repellence and mortality effects of clove and cinnamon essential oils impregnated nets against Anopheles gambiae senso stricto using tunnel test

BackgroundThe control of malaria vectors in Tanzania focuses on the use of synthetic insecticides, which are either impregnated into mosquito nets or used in residual insecticide sprays (IRS). However, one of the major limitations of using insecticides is the development of resistance among the malaria vectors. Thus, there is a need to assess the usefulness of the available natural products such as clove and cinnamon essential oils and determine their repellence and mortality effects against the major malaria vectors. In that context, the current study assessed the chemical composition of clove and cinnamon and the effect of cinnamon and clove essential oils treated nets in causing mortality in the Anopheles gambiae population. MethodA tunnel chamber was used to evaluate the blood-feeding inhibition (repellence) and mortality due to the essential oils impregnated polystyrene nets against Yorkool, a standard Long Lasting Insecticides Nets (LLINs). The unfed 2250 females of An. gambiae s.s. aged 3 days old were used. Each replicate of the Tunnel Chamber experiment used 50 mosquitoes for each concentration(45,55,65 ml/m2) replicated thrice. ResultsThe chemical composition of clove and cinnamon essential oils showed one common chemical, Eugenol (4-alil-2-metoxyphenol), at the highest composition. The findings of the evaluated essential oils showed high mortality and repellence activities against adults of An. gambiae s.s. though they had different active chemical ingredients. The mortality effect was 54%, 70.7% and 77.3% for clove, while for cinnamon it was 89.3%, 88.7% and 89.2% for concentrations of 45 ml/m2, 55 ml/m2 and 65 ml/m2 respectively. ConclusionThe findings of this study have shown that clove and cinnamon essential oils exhibit repellence and toxicity effects against An. gambiae and may be considered as a potential tool for controlling mosquito-human contact.

Determination of knowledge, attitude, and practice of Chinese and local people toward malaria prevention in Kano State, Nigeria.

To date, malaria is still a major public health issue in the world. Africa remains the most affected continent with the highest number of malaria cases and deaths. Since more than one thousand Chinese citizens are living in Nigeria, an examination of their knowledge, attitude, and practice compared with those of the local people may be essential for malaria prevention. This study adopted cross-sectional research. A total of 137 Chinese people and 299 local people residing in Kano State, Nigeria constituted the study subjects. A questionnaire was used for the collection of data on socio-demography and predictors of attitudes. The Cronbach alpha statistic was used to analyze these data. Insecticide spraying, mosquito repellents, and wearing protective clothing at night are the malaria preventive measures by both the local and Chinese people living in Kano state, Nigeria. However, there is a significant difference (P<0.05) between the two groups, with the duration of stay in Nigeria, the use of mosquitoes, attitude, and practices playing impactful roles among the Chinese people. Hence, Chinese people demonstrated better knowledge and control of malaria transmission and prevention than the local people living in Kano State. In conclusion, attitudes and practices toward malaria diseases are the major causes of the high rate of malaria in Nigeria, particularly in Kano State.