ABSTRACT
The bioefficacy of Piper aduncum L. essential oil formulated in aerosol cans was evaluated against Aedes aegypti and Aedes albopictus in a simulated room. The aerosol spray test was based on the Malaysian test standard for aerosol (MS 1221:1991UDC 632.982.2 modified from WHO 2009 methodology) and examined the knockdown effect within 20 minutes of exposure. Mortality rate after 24 hour of holding period was also determined. A commercial aerosol spray (0.09% prallethrin 0.05% d-phenothrin) was also tested as a comparison. Our results showed that the knockdown effect of the commercial aerosol spray and P. aduncum essential oil spray (8% and 10% concentrations) was significantly higher in Ae. albopictus adult females, when compared with that of Ae. aegypti adult females (P<0.05). There was a significant difference in knockdown between commercial aerosol spray and essential oil spray for both Aedes spp. (P<0.05). The essential oil induced significantly higher mortality in Ae. aegypti (80%) than in Ae. albopictus (71.6%) (P<0.05). The commercial aerosol spray caused 97.7% and 86.5% mortality against Ae. aegypti and Ae. albopictus respectively (P<0.05). Based on these data, P. aduncum essential oil has the potential to be used as an aerosol spray against Aedes spp.
ABSTRACT
The potential of the fly adhesives Neopeace®, Neopeace-F101®, and Malaysia Assurance Rats Glue®, for trapping synanthropic lies, was studied in the field. The objective was to compare the efficiency of the 3 adhesives. A chicken farm in Tumbuk, Kuala Langat District, Selangor, 85 km from Kuala Lumpur, was selected as the study site. Twenty pieces of hardboard and 20 pieces of plastic were placed on the ground. Each surface was sprayed with color and impregnated with glue. Bait, chicken intestines, was placed on the center surface to attract houseflies. The numbers of houseflies trapped were counted after 2 hours. The results showed that all 3 glues trapped houseflies efficiently in the field. Malaysia Assurance Rats Glue® was the most efficient (p \< 0.05). The most attractive color for houseflies was yellow (p \< 0.05). Field comparisons of the surfaces demonstrated that hardboard outperformed plastic for trapping houseflies (p \< 0.05). Neopeace® and Neopeace-F101® were equally efficient for attracting both sexes of housefly, while Malaysia Assurance Rats Glue® tended to attract females. The results indicated that all 3 types of glue could be recommended for use in a fly-control program.
ABSTRACT
This study investigated the repellency of Piper aduncum essential oil against Ae. aegypti under laboratory conditions, using human volunteers. Optimum repellency (ED₅₀ value 1.236 \µgcm⁻\² and ED₉₀ 0.845 \µgcm⁻\²) occurred at 90 seconds\’ exposure. Exposures of 60 and 120 seconds yielded much higher ED50 values (2.4170 \µgcm⁻\² and 1.8161 \µgcm⁻\², respectively). There was no significant difference between the ED₅₀ value of the essential oil and DEET (P \> 0.05). P. aduncum essential oil on human skin, at a concentration of 0.4 g, showed an immediate 100% reduction in Ae. aegypti mosquito bite, which reduced to 70.03% at hour 8 post-treatment. Treatment with 10% DEET yielded an immediate 100% reduction until hour 4, then reduced to 73.88% at hour 8 post-treatment. There was no significant difference between the plant essential oil and the commercial product DEET (p \> 0.05). Thus, P. aduncum essential oil is a potential repellent against dengue/dengue hemorrhagic fever vectors.
ABSTRACT
The objective of this study was to evaluate the effectiveness of imidacloprid (Q-Bayt®) against the Kundang and WHO 213 strains of the female housely Musca domestica. By scatter application of 4.0 g Q-Bayt®, after 24 hours, the mortality rates for the Kundang strain and WHO 213 were 36.7 and 54.4%, respectively. At 48 hours’ exposure to Q-Bayt®, the mortality of M. domestica Kundang strain increased to 63.3% and WHO 213 to 73.3%. By paint-on application with Q-Bayt® at 1.5 g/ml, after 24 hours the Kundang strain and WHO 213 showed 38.9 and 48.9% mortality, respectively, whereas 75.6% was obtained for the former and 77.8% for the latter at 48 hours’ post-treatment. On the whole, Student-t test and Mann-Whitney test showed no significant difference (p \> 0.05) in mortality rates between the two strains, with either scatter or paint-on application. Thus, Q-Bayt® is a potential insecticide for controlling the housefly M. domestica. With regard to the dosage used and mortality rates obtained, paint-on application was more efficient than scatter.