Bio-efficacy of Long Lasting Insecticidal Mosquito Nets (LLINs) on Malaria Vector Anopheles Mosquitoes in Malaria-Endemic Areas of Myanmar

Sixty used Long Lasting Insecticidal Nets (LLINs) from six malaria endemicareas of States and Regions of Myanmar were assessed for their bio-efficacy againstAnopheles mosquitoes. Total ten nets were collected from the randomly selectedhousehold of each area. Insecticide susceptibility and bio-efficacy test were doneaccording to WHO testing method. Results revealed that a total of 4470 mosquitoes of 12Anopheles species including main vector and secondary vectors were collected in highdensity in Beelin, Taungoo, Pyin Oo Lwin, Kamamaung and Hpa-an. All collectedmosquitoes were found susceptible to insecticides as recommended by the WHO. Bioefficacy of PermaNet 2.0, DAWA TANA, Yorkool, BASF, Net protect and Yahe LLINs netswere 12(100%), 11/12(91.67%), 4(100%), 8(100%), 5(100%) and 19(100%)respectively. The DAWA TANA net had 20% sensitivity after repetitive washing. Thesensitivity of LLINs nets was higher for all selected areas of States and Regions inMyanmar. The study suggested that there is need to distribute a large number of effectiveLLINs nets in malaria endemic areas as well as the replacement of expired, less effectiveand very old LLINs nets with a new one is also necessary. LLINs nets are very effectiveAnopheles mosquitoes control tools and it can reduce the human-vector contact effectively.Moreover, research on bio-efficacy evaluations of the LLINs nets is required regularly tomaintain and control the transmission of malaria through Anopheles mosquitoes.

Larvicidal activities of chinaberry, neem and Bacillus thuringiensis israelensis (Bti) to an insecticide resistant population of Anopheles arabiensis from Tolay, Southwest Ethiopia

Objective: To elucidate the larvicidal potency of neem, chinaberry and Bacillus thur-ingiensis israelensis (Bti) to larvae of Anopheles arabiensis under semi-field condition and adult susceptibility/resistance to the conventionally used insecticides in Tolay, Southwestern Ethiopia. Methods: Wild collected 3rd and 4th stage larvae were exposed to neem, and chinaberry seed powder dissolved in water and Bti in artificial containers at three treatment levels:0.2, 0.1 and 0.05 g/m2 and controls were free of treatments. Larval and pupal mortalities were monitored daily and residual activities were determined. The experiments were replicated three times. The World Health Organization tube test for all classes of in-secticides was conducted on adult Anopheles arabiensis reared from field collected larvae and pupae. Data were analyzed using STATA software version 11. Results: In the first application, neem powder caused 88.9%, 87.9%and 79.4%larval and pupal mortality at 0.2, 0.1 and 0.05 g/m2 after 4.3, 6.0 and 5.7 days, respectively. The cor-responding killing effect of chinaberry was 80.3%, 62.1%and 30.3%after 7.0, 7.7 and 8.3 days respectively. Bti at all treatments killed 100%after 24 h except 2.7 days for 0.05 g/m2. Adult mosquitoes were susceptible only for fenitrothion and pirimiphos-methyl with 100%mortality while resistant to deltamethrin, alpha-cypermethrin, etofenprox and dichloro-diphenyl-tricgloroethane with only 9.0%, 3.0%, 5.1%and 2.0%mortalities respectively. Conclusions: Neem, chinaberry and Bti showed potent larvicidal and pupicidal activ-ities. However, in the area, high level of mosquito resistance to pyrethroids and dichloro-diphenyl-tricgloroethane was seen which will pose serious challenge to vector control in the future. Therefore, using integrated approach including these botanical larvicides is warranted to manage insecticide resistance.

Larvicidal activities of chinaberry, neem and Bacillus thuringiensis israelensis (Bti) to an insecticide resistant population of Anopheles arabiensis from Tolay, Southwest Ethiopia

Objective To elucidate the larvicidal potency of neem, chinaberry and Bacillus thuringiensis israelensis (Bti) to larvae of Anopheles arabiensis under semi-field condition and adult susceptibility/resistance to the conventionally used insecticides in Tolay, Southwestern Ethiopia. Methods Wild collected 3rd and 4th stage larvae were exposed to neem, and chinaberry seed powder dissolved in water and Bti in artificial containers at three treatment levels: 0.2, 0.1 and 0.05 g/m

Bio-Efficacy of Insecticides Against Fruit Borer (Helicoverpa Armigera) in Tomato (Lycopersicon Esculentum).

Field experiment carried out during kharif, 2012 at Student’s Farm, College of Agriculture, Rajendranagar, Hyderabad to evaluate the efficacy of insecticides viz., emamectin benzoate 5 SG @11 g a.i. ha-1, emamectin benzoate 5 SG @ 22 g a.i. ha-1, profenophos 50 EC @ 500 g a.i. ha-1, profenophos 50 EC @1000 g a.i. ha-1, spinosad 45 SC @ 100 g a.i. ha-1, bifenthrin 10 EC @ 100 g a.i. ha-1 and Bacillus thuringiensis @ 25 g a.i. ha-1against tomato fruit borer (Helicoverpa armigera). Among all the insecticides, profenophos (1000 g a.i. ha-1) was found to be the most effective one with a maximum reduction in fruit borer population (65.20%), minimum per cent of fruit damage (28.80%) and maximum yield (26.43 kg/20 m2) followed by bifenthrin @ 100 g a.i.ha-1 with reduced larval population of 64.51% and damaged fruits 32.60%.

Preliminary Phytochemical, UV-VIS, HPLC and Anti-bacterial Studies on Gracilaria corticata J. Ag

Objective: The present study aimed to investigate the preliminary phytochemical analysis and UV-VIS, HPTC profiling and the antibacterial activity of Gracilaria corticata J. Ag extracts against the Gram positive and Gram negative bacteria. Methods: Preliminary phytochemical screening was carried out by Harborne method. The G. corticata extracts were tested against bacteria by the agar disc diffusion method. Results: The results of the presence study showed the presence of alkaloids, steroids, phenolic groups, saponins, tannin, flavonoids, terpenoids, glycosides and sugars. Proteins, xantoproteins, coumarins and catechin did not show any positive result for their presence in any of the six extracts of Gracilaria corticata tested. The result of the present study revealed the various behavior character of Gracilaria corticata crude drug. The UV-VIS spectrum profile of Gracilaria corticata methanolic, petroleum ether, benzene and aqueous extracts profiles were recorded. The HPLC profile of Gracilaria corticata petroleum ether benzene and aqueous extracts were tabulated. The maximum (9/12 bacterial pathogens) degree of antibacterial activity was observed in isopropanol soxhlet extracts followed by isopropanol cold extracts (7/12 bacterial pathogens). Conclusion: The results of the present study showed that G. corticata may be rich sources of phytoconstituents which can be isolated and further screened for different kinds of biological activities, depending on their reported therapeutic uses.

In vitro anti- bacterial activity of leaves extracts of Albizia lebbeck Benth against some selected pathogens

Objective: To screen the anti-bacterial activity of Albizia lebbeck (A. lebbeck) Benth leaves extract against the selected bacterial pathogens viz., Bacillus subtilis (MTCC441), Escherichia coli (MTCC443), Klebsiella pneumonia (MTCC 109), Proteus vulgaris (MTCC742), Pseudomonas aeruginosa (MTCC741), Salmonella typhii (MTCC733) and Staphylococus aureus (MTCC96).Methods:The leaves extracts of A. lebbeck was tested against bacteria by the agar disc diffusion method. Results: Results of the present study indicated that different extracts of A. lebbeck showed inhibitory effects against the pathogens. The present study results demonstrated that methanolic extracts of A. lebbeck conferred the widest spectrum activities that inhibited the growth of all studied pathogens with the maximum zone of inhibition. The methanolic extracts ofA. lebbeck illustrated the highest zone of inhibition against the pathogens Bacillus subtilis (16 mm), Escherichia coli (22 mm), Klebsiella pneumonia (11 mm), Proteus vulgaris (18 mm), Pseudomonas aeruginosa (22 mm), Salmonella typhii (23 mm) and Staphylococus aureus (17 mm). The ethyl acetate extracts demonstrated maximum zone of inhibition against Escherichia coli (26 mm), Pseudomonas aeruginosa (22 mm) and Klebsiella pneumonia (16 mm). Conclusions: It is expected that this study would direct to the establishment of some active compounds that could be used to formulate new and more potent anti-bacterial drugs of natural origin.