| Popis: |
Stored grains represent the main constituent of food in Egypt. The rust-red flour beetle, Tribolium castaneum (Herbst) comes on the top of the stored grain pests caused up to 40% weight reduction pills. The study aimed to determine the insecticidal activity of four every days-used essential oils (EOs) extracted from Allium sativum (Garlic), Cinnamomum camphora (Camphor), Syzygium aromaticum (Clove) and Brassica junicea (Mustard) against adults of T. castaneum under laboratory conditions. Also, the effects of these oils at sub-lethal dose on the biological and physiological responses of the beetle were tested. In addition, the effect on grains germination was determined. Gas Chromatograph-Mass Spectrometry (GC-MS) was used to analyze the major constituents of the oils. The results indicated that, the tested EOs have insecticidal, anti-feeding, and repellent activities against the adults. Clove oil had the highest insecticidal efficacy (LC50) (1.44 ml/kg grains), followed by Garlic (2.09 ml/kg grains), Mustard (3.67 ml/kg), and Camphor (2.75 ml/kg), respectively. Clove and Camphor showed adverse effects on the physiological status of adults. Also, the tested EOs significantly affect germination. Clove showed the lowest effect on grains germination percentages: 73.35 and 61.65% at LC50 and LC90 levels. Spectra pattern of EOs exhibited different bioactive components, where decanes, cosane, and sulphide groups showed the highest of abundance. On the other hand, the cytotoxic effects of both clove and garlic oils were investigated against WI-38 human cells by using MTT test. They showed low cytotoxic effect. We can conclude that. Clove and Garlic oils could be considered promising effective alternatives to control T. castaneum with biosafety profiles. |
