Efficacy of three essential oils and their nano-particles against Sitophilus granarius under laboratory and store conditions

The effect of three essential oils and their nano-preparations (castor, mustard and purslane) were tested against the granary weevil Sitophilus granarius under laboratory and stored conditions. Purslane oil (bulk and nano) had strong insecticidal efficacy and was significantly highly effective tested oil against granary weevil with 86.64, 75.21, 55.32, and 18.61% mortality obtained at 5, 2.5, 1.25 and 0.63% concentrations, respectively. While, the mortality values reached 95.61, 73.51, 58.39 and 20.61% when the adults were exposed to 0.5, 0.25, 0.13, 0.06 concentrations of nano-purslane, respectively. Castor oil had moderate effect and mustard was the least one. Nano-purslane was highly significantly more effective as sterilizer against adult weevils in comparison with other tested nano-oils. The mean number of eggs/female recorded 3.0 ± 3.8, 22.0 ± 7.8 and 28.8 ± 7.9 eggs/female in case of purslane, castor and mustard, respectively in comparison to control (198 ± 4.9 eggs/female). After 125 days of storage, the percentage of emerged weevils were 21 and 7% in case of purslane oil (bulk and nano), respectively comparing with untreated control (98%).