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Remote sensing has become a worldwide tool for natural resource managers as well as government agencies, industry and conservation organizations. Furthermore, it is a valuable technique in detecting and mapping different types of cosmopolitan hazards. Activities and development along the Egyptian Red Sea coast have grown in fast and remarkable manner. Tourism is one of the leading sources of income to Egypt's economy; tourism activities can affect marine and coastal living and nonliving components of local ecosystems. Sea turtles are among the most threatened and endangered animals due to human encroachments that affect nesting grounds and fishing activities that affect animals at foraging grounds and during migrations. The hawksbill Eretmochelys imbricata is a critically endangered species that nests in Giftun Island in the Red Sea off Egypt. Remote sensing and satellite imagery provided observations that show that Giftun Island is suffering from anthropogenic and physical threats; the results explain a decline in nests of Eretmochelys imbricata. Keywords: Remote sensing, Turtles, Red Sea, Eretmochelys imbricata, Big Giftun Island

The risk of using synthetic insecticides to the environment, human health, and the emergence of new genera of pests resistant to that kind of drugs, have led to attention in natural compounds. The present study aimed at evaluating the insecticidal activity of 0.25–6 mg/cm2 of basil (Ocimum basilicum), black seeds (Nigella sativa), and lavender (Lavandula angustifolia) essential oils (EOs) against one of the major stored product pests, Sitophilus oryzae (L.). This was done by assessing mortality and repellent percentage assay in the adult stage, as well as analysing up and down-regulated genes associated with toxicity effect of selected EOs. The three studied EOs showed a toxic effect on S. oryzae, where O. basilicum and L. angustifolia EOs explicated 100% mortality at 6mg/cm2 after 48 and 24 h, respectively. The highest repellence activity was recorded for O. basilicum EO at 0.75 mg/cm2 with value 82.3% after exposure time 5 h. In the highest dose (6 mg/cm2), the maximum up-regulated expression level of detoxification DEGs genes (CL1294 and CL 8) and cytochrome p45o gene (CYP4Q4) in Lavandula angustifolia EOs exhibited 8.32, 6.08, and 3.75 fold changes, respectively, as compared with 4.76 fold at 10 ppm malathion and 1.02 fold change in acetone control.

The risk of using synthetic insecticides to the environment, human health, and the emergence of new genera of pests resistant to that kind of drugs, have led to attention in natural compounds. The present study aimed at evaluating the insecticidal activity of 0.25–6 mg/cm2 of basil (Ocimum basilicum), black seeds (Nigella sativa), and lavender (Lavandula angustifolia) essential oils (EOs) against one of the major stored product pests, Sitophilus oryzae (L.). This was done by assessing mortality and repellent percentage assay in the adult stage, as well as analysing up and down-regulated genes associated with toxicity effect of selected EOs. The three studied EOs showed a toxic effect on S. oryzae; where O. basilicum and L. angustifolia EOs explicated 100% mortality at 6 mg/cm2 after 48 and 24 h, respectively. The highest repellence activity was recorded for O. basilicum EO at 0.75 mg/cm2 with value 82.3% after exposure time 5 h. In the highest dose (6 mg/cm2), the maximum up-regulated expression level of detoxification DEGs genes (CL1294 and CL 8) and cytochrome p45o gene (CYP4Q4) in Lavandula angustifolia EOs exhibited 8.32, 6.08, and 3.75 fold changes, respectively, as compared with 4.76 fold at 10 ppm malathion and 1.02 fold change in acetone control.