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Background. Aedes aegypti mosquitoes are the main vectors of dengue viruses to humans. Understanding their biology and interactions with the pathogen are prerequisites for development of dengue transmission control strategies. Mosquito salivary glands are organs involved directly in pathogen transmission to vertebrate hosts. Information on the spatial distribution of gene expression in these organs is expected to assist in the development of novel disease control strategies, including those that entail the release of transgenic mosquitoes with impaired vector competence. Results. We report here the hybridization in situ patterns of 30 transcripts expressed in the salivary glands of adult Ae. aegypti females. Distinct spatial accumulation patterns were identified. The products of twelve genes are localized exclusively in the proximal-lateral lobes. Among these, three accumulate preferentially in the most anterior portion of the proximal-lateral lobe. This pattern revealed a salivary gland cell type previously undescribed in Ae. aegypti, which was validated by transmission electron microscopy. Five distinct gene products accumulate in the distal-lateral lobes and another five localize in the medial lobe. Seven transcripts are found in the distal-lateral and medial lobes. The transcriptional product of one gene accumulates in proximal- and distal-lateral lobes. Seven genes analyzed by quantitative PCR are expressed constitutively. The most abundant salivary gland transcripts are those localized within the proximal-lateral lobes, while previous work has shown that the distal-lateral lobes are the most active in protein synthesis. This incongruity suggests a role for translational regulation in mosquito saliva production. Conclusions. Transgenic mosquitoes with reduced vector competence have been proposed as tools for the control of dengue virus transmission. Expression of anti-dengue effector molecules in the distal-lateral lobes of Ae. aegypti salivary glands has been shown to reduce prevalence and mean intensities of viral infection. We anticipate greater efficiency of viral suppression if effector genes are expressed in all lobes of the salivary glands. Based on our data, a minimum of two promoters is necessary to drive the expression of one or more anti-dengue genes in all cells of the female salivary glands. © 2011 Juhn et al; licensee BioMed Central Ltd.

Tomato leafminer, Tuta absoluta is an indigenous insect pest of solanaceous crops in South America, which is now an important quarantine insect pest in many other parts of the world. Geographical range of T. absoluta is rapidly increasing. It has been spreading in Asian countries since first reported from Turkey in 2009, Azarbaijan province in North Western Iran in 2010 and in 2014 it has reached India. Its damage is severe on tomatoes and possible threat to food production hence an emerging problem to food security. Tuta absoluta was not reported earlier in Pakistan. A high attack of Tuta absoluta in 2017-2018 in Multan on tomato crop was observed. Samples were recovered from tomatoes grown under plastic tunnels. Detection was carried out by incubated infested tomato leaves and fruits till adult eclosion in the mesh cages. Larvae were observed under microscope. Leaves and fruit damage symptoms were compared with available data. Adults were identified morphologically. Genitalia of adults proved that insect pest was tomato leafminer, Tuta absoluta. Furthermore, it was confirmed through sex pheromone traps where moths of Tuta absoluta were caught from same location from where samples were taken. Hence, it is confirmed first report of T. absoluta in Pakistan. Further studies are needed to confirm the occurrence of this emerging insect pest on alternative host plants in different areas of Pakistan. It's an alert for quarantine department to take strict measures for its entry points through trade before it emerges as threatening insect pest in Pakistan to tomato industry. [ABSTRACT FROM AUTHOR]

Fruit flies are harmful economic pests that infect a broad range of fruits and vegetables across the world due to their high reproductive capacity, polyphagous nature, host range, mobility, and environmental adaptability. Traditional management methods are no longer viable due to the massive fly populations, pesticide resistance, pest outbreak, environmental risks and health hazard residues. This study was conducted to evaluate the chemosterilizing and mortality factors by using a combination of exclusion experiments. Infection through chemosterilant and entomopathogenic fungi has also been demonstrated to reduce fruit fly fecundity, fertility, adult emergence and mortality that can contribute to fruit fly suppression in the long-term. Pyriproxyfen, novaluron, lufenuron, buprofezin, and flubendiamide (50-300 ppm/ 5 mL diet) were tested in oral bioassays against the newly emerged Beauveria zonata under lab conditions. The results showed that fecundity and adult emergence is higher at low doses and vice versa. Among the investigated chemicals, lufenuron induced the lowest fecundity 31.05% and the lowest adult emergence rate of 19.85% at 300 ppm/5 mL of treated diet. Whereas in crosses between treated males with treated females, lufenuron treatment resulted in the lowest fecundity (45.52%) and adult emergence rate (51.73%) as compared to other crosses. Generation-wise reduction percentage observed in G1, G2 and G3 was 54.69, 24.47 and 11.51% respectively. Pathogenicity of B. bassiana showed 4-6% larval mortality and the pupal survival was reduced by 87-92% on the sand substrate and caused malformation. [ABSTRACT FROM AUTHOR]

ABSTRACT: An experiment was conducted to determine the comparative biology of Trilocha varians on different host plants such as Ficus benjamina, Ficus religiosa, Ficus carica and Ficus elastica under laboratory conditions at 26.50C temperature and 60.5% relative humidity. Results showed that growth and development of T. varians completed successfully on F. benjamina. It was observed that only F. benjamina was the preferable host for T. varians. After one day of hatching from eggs, larvae were died on the F. carica and F. elastica while some larvae were fully developed on F. religiosa. The study concluded that F. benjamina was the major host plant followed by F. religiosa. [ABSTRACT FROM AUTHOR]

Abstract Background Aedes aegypti mosquitoes are the main vectors of dengue viruses to humans. Understanding their biology and interactions with the pathogen are prerequisites for development of dengue transmission control strategies. Mosquito salivary glands are organs involved directly in pathogen transmission to vertebrate hosts. Information on the spatial distribution of gene expression in these organs is expected to assist in the development of novel disease control strategies, including those that entail the release of transgenic mosquitoes with impaired vector competence. Results We report here the hybridization in situ patterns of 30 transcripts expressed in the salivary glands of adult Ae. aegypti females. Distinct spatial accumulation patterns were identified. The products of twelve genes are localized exclusively in the proximal-lateral lobes. Among these, three accumulate preferentially in the most anterior portion of the proximal-lateral lobe. This pattern revealed a salivary gland cell type previously undescribed in Ae. aegypti, which was validated by transmission electron microscopy. Five distinct gene products accumulate in the distal-lateral lobes and another five localize in the medial lobe. Seven transcripts are found in the distal-lateral and medial lobes. The transcriptional product of one gene accumulates in proximal- and distal-lateral lobes. Seven genes analyzed by quantitative PCR are expressed constitutively. The most abundant salivary gland transcripts are those localized within the proximal-lateral lobes, while previous work has shown that the distal-lateral lobes are the most active in protein synthesis. This incongruity suggests a role for translational regulation in mosquito saliva production. Conclusions Transgenic mosquitoes with reduced vector competence have been proposed as tools for the control of dengue virus transmission. Expression of anti-dengue effector molecules in the distal-lateral lobes of Ae. aegypti salivary glands has been shown to reduce prevalence and mean intensities of viral infection. We anticipate greater efficiency of viral suppression if effector genes are expressed in all lobes of the salivary glands. Based on our data, a minimum of two promoters is necessary to drive the expression of one or more anti-dengue genes in all cells of the female salivary glands.

Background: Mosquito Control Programs are articulated to control Mosquito Borne Diseases and success of such programs depends on the activities of field workers, and their adherence to the standard operating procedures (SOP's) is governed by their knowledge, attitudes, and practices (KAP). Present study was intended to assess the KAP of mosquito control workers of Pakistan to get an exact depiction of prevailing situation., Methods: A cross-sectional descriptive study was conducted in March-April 2020. Questionnaire containing 30 closed and open-ended questions were administrated to participants. Knowledge and practices were evaluated using a scoring system i.e., by giving 1 point to each correct answer while attitude questions were analyzed individually and expressed in percentage for each response., Results: Total 639 workers were interviewed, mean age was 29.8 (SD ±7.87) years, majority (65.1%) was in age group of 18-30 years. Mean knowledge score was 6.96±1.28 (range 0-9) with 77.36% correct answers (P= 0.073). Mean practices score was 7.00±1.62 (range 2-9) with 77.83% appropriate answers (P< 0.001). Both knowledge and practices scores were higher for permanent employees, practices score increased with increase in job experience. Very weak positive correlation (r= 0.127) was observed between knowledge and practice scores., Conclusion: Appropriate practice correlates with better knowledge and positive attitude towards control activities. Hence, training on protection and protective measures for having a positive attitude among healthcare workers is necessary against the fight with mosquitoes., Competing Interests: Conflict of interest statement The authors declare there is no conflict of interests., (Copyright © 2023 The Authors. Published by Tehran University of Medical Sciences.)

The indiscriminate application of synthetic pesticides on horticultural plants for the management of Bactrocera zonata has both economic and environmental implications due to the biomagnification of harmful residues in humans via the food chain. This necessitates the use of some eco-friendly control measures such as insect growth regulators (IGRs) as an alternative. A laboratory experiment was laid out to determine the potential chemosterilant effect of five IGRs including pyriproxyfen, novaluron, lufenuron, buprofezin, and flubendiamide at six different concentrations on B. zonata after treating adult diet. Using the oral bioassay, B. zonata were fed on IGRs impregnated diet (50-300 ppm/5 mL diet) which was replaced with the normal diet after 24 h of feeding. Ten pairs of B. zonata were placed in a separate plastic cage accommodating an ovipositor attractant guava for eggs collection and calculation. An analysis of the result revealed that fecundity and hatchability were higher at a low dose and vice versa. Lufenuron at 300 ppm/5 mL of diet significantly decreased the fecundity rate (31.1%) as compared to pyriproxyfen, novaluron, buprofezin and flubendiamide, which had 39.3%, 39.3%, 43.8%, and 47.5%, respectively. The lowest hatchability (19.9%) was noted in lufenuron treated diet followed by pyriproxyfen, novaluron, buprofezin, and flubendiamide, which had 22.1%, 25.0%, 30.9%, and 31.6%, respectively. Furthermore, in a population of crosses between the lufenuron treated male and female, a significant decrease in fecundity (45.5%) and hatchability (51.7%) was noted as compared to other IGRs. Overall, this study identified the chemosterilant potential of lufenuron on the population of B. zonata which can be integrated for its management strategy.

Termites are a significant pest of buildings, agriculture, and trees, and are mainly controlled by baiting. However, baiting systems are available for only lower termites (Rhinotermitidae) not for higher termites (Termitidae). Termite foraging behavior associated with baiting systems varies among species and families, and plays a significant role in baiting success. Here, foraging behavior of Odontotermes obesus (Blattodea: Termitidae: Macrotermitinae), a fungus-growing higher termite, was investigated relative to three bait-station sizes (small, medium, and large) containing different quantities of food. Significantly more workers recruited to large stations (470/station) compared to medium (246/station) and small (124/station) stations. Abundance of O. obesus in large and medium stations significantly positively correlated with relative humidity whereas negative but non-significant correlations were observed with temperature in large and medium stations. Total and continuous contacts with the stations increased with time and were greater in large stations. Station abandonment due to disturbance was significantly less in large stations (3%) followed by medium (9%) and small stations (20%). Our results suggest that large stations (≈8 litres volume) work best for population management of O. obesus and other related fungus-growing higher termites.

In developed and underdeveloped countries, ticks are important vectors transmitting various pathogens that cause diseases of veterinary and public health importance, like babesiosis, theileriosis, Crimean‑Congo haemorrhagic fever (CCHF) and many more. Many species of ticks have been reported in scientific literature from Pakistan, which need to be listed for ready reference. For this purpose, a checklist of tick species recorded in Pakistan is presented here after comprehensive review of the available literature on the subject. Overall, nine genera and 53 species of ticks infesting animals in Pakistan are presented in this checklist.

Indian siris, Albizia lebbeck (L.) Benth. (Fabaceae: Mimosoideae) has significant importance to human beings for its multipurpose use. Insects play a crucial role in the pollination biology of flowering plants. In the current study, we studied the pollination biology of A. lebbeck with special reference to insect floral visitors. The effectiveness of floral visitors was investigated in term of visitation frequency, visitation rate and pollen load during 2012 and 2013. In the second experiment, effect of pollinators on yield of A. lebbeck was studied in open and cage pollination experiments. Floral visitor fauna of A. lebbeck included eight-bees, two wasps, two flies, and two butterflies species. Among them, Apis dorsata , Apis florea , Amegilla cingulata, and Nomia oxybeloides had maximum abundance ranging from 349-492, 339-428, 291-342 and 235-255 numbers of individuals, respectively during two flowering seasons. A. dorsata had the highest visitation frequency (6.44 ± 0.49-8.78 ± 0.48 visits/flower/5min) followed by Amegilla cingulata (6.03 ± 0.43-7.99 ± 0.33 visits/flower/5min) and A. florea (3.61 ± 0.31-4.44 ± 0.18 visits/flower/5min). A. dorsata , N. oxybeloides, and Amegilla cingulata had the highest visitation rates (18.904 ± 1.53-11.43 ± 1.17 flower visited/min) and pollen load (15333 ± 336.22-19243 ± 648.45 pollen grains). The open pollinated flowers had significantly higher capsule weight (4.97 ± 0.21 g), seed weight (1.04 ± 0.05 g), seed numbers per pod (9.80 ± 0.34) and seed germination percentage (84.0 ± 1.78%) as compared to caged flowers. The results suggested bees especially A. dorsata , N. oxybeloides and Amegilla cingulata could be effective pollinators of A. lebbeck ., (© 2018 Production and hosting by Elsevier B.V. on behalf of King Saud University.)

Background: Dengue fever (DF) has become a major public health concern globally. It is an infection caused by a virus of the family Flaviviridae, with five serotypes (DENV 1-5). Recent years have seen an increase in the prevalence of the disease in Pakistan. The current study was carried out to evaluate the clinical features, laboratory findings and demographic information of the patients reported during the dengue outbreak in Multan of Pakistan in 2015., Methods: The hospital documentation-based data of confirmed DF cases were collected for the 6 months period from a Tertiary Care Hospital in Multan, Pakistan. The patients were labeled as confirmed on the basis of NS1 and IgM positivity by ELISA. The data collected were analyzed using SPSS., Results: Overall, 361 patients were investigated (78.67% males and 21.33% females), with maximum infection rate in the age group of 18-35yr (50.41%). Mean hospital stay was 2.64d (SD 1.2), while mean fever duration was 5.27 (SD 1.57). Outbreak occurred during the months from Jul-Dec, while maximum patients were reported in Oct (287). No mortality was reported, and all patients recovered., Conclusion: Better management practices and timely reporting can reduce the risk factors associated with the disease., (Copyright© Iranian Society of Medical Entomology & Tehran University of Medical Sciences.)

The house fly, Musca domestica L., is an important ectoparasite with the ability to develop resistance to insecticides used for their control. Thiamethoxam, a neonicotinoid, is a relatively new insecticide and effectively used against house flies with a few reports of resistance around the globe. To understand the status of resistance to thiamethoxam, eight adult house fly strains were evaluated under laboratory conditions. In addition, to assess the risks of resistance development, cross-resistance potential and possible biochemical mechanisms, a field strain of house flies was selected with thiamethoxam in the laboratory. The results revealed that the field strains showed varying level of resistance to thiamethoxam with resistance ratios (RR) at LC50 ranged from 7.66-20.13 folds. Continuous selection of the field strain (Thia-SEL) for five generations increased the RR from initial 7.66 fold to 33.59 fold. However, resistance declined significantly when the Thia-SEL strain reared for the next five generations without exposure to thiamethoxam. Compared to the laboratory susceptible reference strain (Lab-susceptible), the Thia-SEL strain showed cross-resistance to imidacloprid. Synergism tests revealed that S,S,S-tributylphosphorotrithioate (DEF) and piperonyl butoxide (PBO) produced synergism of thiamethoxam effects in the Thia-SEL strain (2.94 and 5.00 fold, respectively). In addition, biochemical analyses revealed that the activities of carboxylesterase (CarE) and mixed function oxidase (MFO) in the Thia-SEL strain were significantly higher than the Lab-susceptible strain. It seems that metabolic detoxification by CarE and MFO was a major mechanism for thiamethoxam resistance in the Thia-SEL strain of house flies. The results could be helpful in the future to develop an improved control strategy against house flies.

Background: House flies are of major public health concerns in areas with poor sanitation and hygienic conditions. Unfortunately, sanitation and hygiene have always been ignored in dairy farms particularly in the developing or low-income countries. Management of these flies mostly depends on the awareness regarding associated hazards and protective measures taken by the people to minimize risks associated with flies. The present study therefore explores the knowledge, attitude and practices taken by dairy farmers in Punjab, Pakistan against house flies., Methods: The present study was based on a cross sectional self administered survey to a convenience sample of 173 small scale dairy farmers in four localities - Multan, Lahore, Shorkot and Faisalabad - of Pakistan. The relationships between socio-demographics, knowledge and preventive practices were investigated through logistic regression analysis and chi-square test of association., Results: Considerable number of dairy farmers 71/173 (41.04%) had no idea about the problems associated with house flies. Although 77/173 (44.51%) dairy farmers reported house flies as disease transmitters, only 23 (29.87%) farmers were familiar with diseases and 22 (28.57%) had somewhat idea of the mode of disease transmission. We found a positive association between dairy farmer's education level and overall knowledge of house flies in multivariate analysis. Farmer's education level and knowledge of the house flies breeding sites had a positive association with the adoption of house fly prevention practices by the respondents. However, knowledge of the problems associated with house flies and preventive measures had no association with house fly prevention practices., Conclusion: The present ethnoentomological survey provides information about knowledge, attitude and practices of dairy farmers related to house flies in Punjab, Pakistan. We conclude that the farmers' education level and knowledge of the breeding sites had a positive association with the adoption of prevention practices against house flies. The study also highlights the need of targeting the lack of knowledge of dairy farmers for the successful management of house flies.