Biocontrol efficacy of bay essential oil against housefly, Musca domestica (Diptera: Muscidae)

Abstract

Background: The synanthropic housefly, Musca domestica, augments the transmission of several detrimental diseases like cholera and avian flu. Consequently, during the last century, many physico-chemical methods including synthetic compounds have been applied for its control. But these methods have proven to be prohibitive due to their side effects and serious issues like resistance development, environmental contamination, and detrimental effects on non-target fauna. Therefore, in view of these objectives, we investigated the effects of bay essential oil (EO) against M. domestica. Methods: The attractant/repellent assays were conducted by double choice technique. Different enzyme assays evaluating the effect of LC 50 concentration of the tested essential oil on larval gut were taken into consideration. To determine the composition, the tested oil was subjected to GC-MS/MS analysis. Further, the morphological alterations caused by EO treatment to third instar larvae were observed in a Nova Nano SEM machine. Data was statistically analyzed by one-way ANOVA using Tukey's test (p < 0.001). The LC 50 and LC 90 values were calculated by probit analysis. Results: The adulticidal bioassay revealed significant effects with LC 50 concentration as 43.03 mg/dm 3 against the newly emerged adult flies while in larvicidal assay mortality was dose dependent showing maximum effect at LC 50 0.0629 μg/cm 2. The pupicidal activity was more effective at a dose of LD 50 64.09 μl/0.25 L of air which either killed the pupae or caused deformity in the emerged adults. Likewise total sugar, protein, glycogen, and lipid contents of larvae were reduced after treatment with EO when compared with the normal larvae along with some gut enzymes. The EO reduced the acetylcholinesterase activity from 0.013 U/mg protein in normal larvae to 0.0093 U/mg protein after EO treatment. The GC-MS/MS analysis of the bay EO showed the abundance of myrcene, linalool, eugenol, chavicol, and anethole along with diterpenoid, geranylgeraniol. However, the insecticidal activity of tested EO might be majorly imparted by eugenol content. The FESEM analysis showed shrinkage of integument and distortion to intersegmental regions caused by the tested compound. Conclusion: The present study concludes the significant efficacy of bay EO against M. domestica which could be employed to breakdown its population below threshold levels to prevent the menace of vector-borne diseases.

Bioefficacy of Lemongrass and Tea Tree Essential Oils Against House Fly, Musca domestica

“…The culture of housefly, M. domestica procured from the national chemical laboratory (NCL), Pune (M.S. ), India, was maintained at 28 ± 2 °C and 60–70% R.H. for several generations in plastic jars of 35 × 15 cm dimension as described previously [ 7 ]. The jars were covered with muslin cloth to prevent the flies from escape.…”

“…The larvicidal assays were carried out by using the residual film method [ 7 ] with slight modifications. Briefly, the effect of different concentrations of tested oils, were checked on 3rd instar larvae ( n = 10) to determine the LC 50 and LC 90 concentrations.…”

“…The adulticidal assay on M. domestica was carried out according to the method described previously [ 7 ] with minor changes. The bioassays were designed such that the flies would have a maximum probability of exposure to the tested concentration of EOs.…”

“…The attractant/repellent assays were carried out by double choice method [ 7 ] where 20 individuals of newly emerged adult flies were released in a cage containing 2 conical flasks. One flask contained 0.1% test oil in 5 mL (v/v) of milk, while the other contained acetone as solvent with 5 mL of milk to serve as a control.…”

“…The α- and β-glucosidase activities were determined as per the method described previously [ 7 ] using p-nitrophenol as standard. The reaction mixture contained 50 µL of enzyme sample with 75 µL of 5 mM p -N-α-D-glucopyranoside or p -nitrophenyl–β–d-glucopyranoside (as substrates) for α- and β glucosidase, respectively.…”