Tropospheric ozone (O 3) is a naturally occurring gas in the atmosphere. However, the concentration of O 3 increased in the 20 th century. Although the effects of O 3 on vegetation have been extensively studied since the 1950s, limited information exists regarding the effects of O 3 on insect herbivores. In particular, evidence is lacking regarding the effects of O 3 on the biology of insect herbivores. Agelastica coerulea (Baly, 1874) is a coleopteran species that grazes on Betulaceae plants. In this study, to investigate the effects of O 3 on A. coerulea biology for the first time, female adult insects were collected from Japanese white birch trees grown in a Free Air Controlled Exposure System (FACE) in Sapporo, Japan. These beetles inhabited trees exposed either to ambient or to elevated O 3 for 23 days. After 2 collection, the enzyme activities in the beetles were measured. Elevated O 3 led to a greater total antioxidant activity and lower α-and β-esterase activities, a phenomenon that may suggest an increased resistance of the beetles to stress. Our results are further discussed with regard to biological and toxicological aspects. Collectively, our findings indicate that total antioxidants and α-and β-esterase activities can serve as effective O 3 biomarker systems in this beetle species. This adaptive response of the beetle, which was induced by moderate O 3 exposure, should be further tested across generations and for its protection against greater exposure.

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The red palm weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera, Curculionidae) is the most serious insect pest of cultivated palm trees in several countries. The purpose of the present work is to study Susceptibility of five date palm trees varieties to infestation with red palm weevil, Rhynchophorus ferrugineus(OLIVIER) during four successive years (2010-2013) and quantitative variations of some chemical components. The results appeared that Zaghloul& Hayani varieties were the more preference for infestation than other varieties, The percentages of infestation were about (27, 16.5, 16.8 and 13.8 %) for Zagloul, (25, 15.3, 11.2 and 11.3 %) for Hayani , (19, 8, 5 and2 %) for Bent Eshia, (12, 5, 1and 0 %) for Samani and (4, 3, 0 and0%) for Amry variety during the four successive seasons, respectively.Chemical analysis for trunk tissues of date palm tree varieties showed clear variations between the amount of chemical components Phenols, Alpha esterase's, Phenol oxides, and total proteins appeared positive significant variation infested palm trees as compared with to total nitrogen, Free amino acids ,total carbohydrates ,Tannins, , B-glycosidase, which showed positive and non-significant variation in all infested date palm varieties.

lant proteinase inhibitors were (PIs) extracted from tomato leaves (Solanum lycopersicum L.) to test their effect on the digestive physiology of Spodoptera littoralis in relation to growth and development of the larvae. Larvae fed on leaves treated by crude extract protein of PIs (10 mg protein m1-1). The continuous feeding of the cotton leafworm on treated leaves from egg hatching led to significant inhibition of the 4 th larval instar gut proteases (decreased by 32.9% as compared to control). Effects of PIs on protein digestion suggested that PIs might alter protein metabolism. The results showed that total proteins were significantly reduced in treated larvae as compared to control (P< 0.05), but free amino acids were more affected than proteins (P< 0.01). Also, enzymes related to protein metabolism were also changed due to feeding on leaves treated by PIs. On the other hand, the study revealed that continuous feeding on tomato PIs reduced S. littoralis larval and papal weight, and caused 6.7% abnormalities i.e. appearance of larval-pupal intermediates. It could be suggested that tomato PIs act by in vivo inhibiting of the cotton leafworm gut proteases, not by resulting in hyperproduction of proteolytic enzymes related to protein metabolism such as Glutamic oxaloacetic transaminase (GOT) to compensate the reduced amount of available proteins due to treatment. It is the first time to test PIs activity towards the native pests. Results presented here demonstrating that the use of tomato PIs might be of a significant value in the field of pest control.