bactrocera zonata

In the present study, the toxicity of three oxygenated monoterpenes, viz., (R)-carvone, (R)-camphor and (1R, 2S, 5R)-menthol was evaluated against the adults of the peach fruit fly, Bactrocera zonata (Saunders). Effects of these monoterpenes on oviposition, adult longevity and ovarian development have also been studied. The tested compounds revealed strong toxic effect against the adults of B. zonata. Nevertheless, (-)-carvone showed higher insecticidal activity than (1R, 2S, 5R)-menthol and (R)-camphor. Moreover, the tested monoterpenes induced significant reduction in female longevity at 20 and 50 mg/kg compared with control, with (-)-carvone being the most effective monoterpene. In addition, egg deposition was completely inhibited when the adults were treated with (-)-carvone at 20 and 50 mg/kg, and (1R, 2S, 5R)-menthol and (R)-camphor at 50 mg/kg. Histological studies indicated that monoterpenes induced delay in the development of ovarioles of females that fed on artificial diet treated with 20 and 50 mg/kg of compounds. Changes, such as empty egg chambers; constricted germarium, vacant spaces between ovarioles and failure of oocyte formation were observed.

Bactrocera zonata (Saunders) (Diptera: Tephritidae), an extremely aggressive species infesting some of the main commercial fruit and vegetables, has been subjected to a diverse array of control approaches. In the current study, performance of various Methyl Eugenol (ME) dispensers in combination with an organophosphate insecticide, Malathion, were evaluated against B. zonata in two consecutive years (2006-2007). Treatments efficacy was studied in various months using the criterion of trapped B. zonata flies. ANOVA revealed a significant difference among various application methods in both fruit infestation rate and capture of B. zonata flies. So that impregnation of chipboard block in ME caused the lowest B. zonata infestation and the highest B. zonata capturing values in both years. Population fluctuation study revealed a major peak for B. zonata in September i.e., mango ripening time. According to our results, it could be suggested that chipboard dispenser is the best application method as attractant in bait trap which exhibits more potent and longer lasting activity.