n a laboratory study, the impact of crude chitinase from Aeromonas hydrophila on the nutrient indices and on the major biochemical components of Galleria mellonella was studied. Fourth larval instar of Galleria mellonella was treated with 135.0 U/mg protein (LC50). Treatment with crude chitinase reduced the larval feeding efficiency, retarded larval growth and reduced larval weight, whereas approximate digestibility was increased. The total protein contents in the supernatant of the homogenate larvae post-treatment was decreased, as affected by crude chitinase (LC50) comparing with the check treatment. A significant reduction in the total lipid content was observed and it may due to its conversion to proteins in order to compensate the reduction in protein content or to produce supplementary energy. The total carbohydrate contents were significantly reduced to be ~111.17±4.24 µg/larva with respect to the control (147.21±1.77 µg/larva). Crude chitinase from Aeromonas hydrophila may serve as a powerful biocontrol tool against insects and provide a suitable substitute for synthetic pesticides.

he study is aimed to isolate and identify a potential entomopathogenic fungus from fields infested with spider mites and evaluate them as a bio-rationale agent against Tetranychus urticae Koch., which is an important agricultural pest that infests horticultural crops in both field and greenhouses. Macroscopic and microscopic characteristics showed that the obtained entomogenous isolate was Purpureocillium lilacinum (formerly, Paecilomyces lilacinus). P. Lilacinum demonstrated mortality rates on adult females of T. urticae of 71.19 and 77.97% with conidial concentrations of and 1.6 , respectively, 10 days after application. Median lethal concentration of P. lilacinum was 2.85 10 6 conidia/ml. Enzymatic activity of P. lilacinum was evaluated. In this context, chitinolytic activity of P. lilacinum was relatively weak, since the clear halo obtained was only 4.43 mm in diameter. The activity of chitinase enzyme insignificantly increased over the incubation period of 10 days. In contrast, proteolytic activity of P. lilacinum was high and showed a clear zone (25.8 mm) around the colony after 10 days. So, it is concluded that P. lilacinum has a potential biological control against T. urticae. Finally, evaluation of the ethyl acetate extract of P. lilacinum showed acaricidal potency since it exhibited LC 50 values of 10.49 mg/ml for eggs and 30.75 mg/ml for adults. So, it is concluded that P. lilacinum has a potential biological control against T. urticae.

reater date moth, Arenipses sabella Hmps. (Lepidoptera: Pyralidae), is one of the devastating pests to date palm production in most date palm producing countries. The current study aimed to estimate the distribution and the abundance of A. sabella larval population and the associated parasitoids across the Egyptian oases along the Egyptian Western Desert over a two years period (2017)(2018). In addition, infestation percentages inflicted on both bunch stalk and fallen fruits were recorded in all the examined oases. At the onset of date fruit harvesting season, bunch stalks of 10 fruitful trees and 100 fallen fruits had been sampled and investigated in 60 experimental sites allover the oases. The obtained findings declared that percentages of infested bunches behaved proportional trend toward the north direction, i.e. the percentage of infested bunches recorded its highest value in the experimental sites of Siwa oasis. The larval abundance across the examined sites was high in the northern oases whereas in the south larval abundance subsided to less than 1%. The more larval abundance percentages in the northern oases were corresponding to the more date fruit infestation. During the context of this study, the most abundant larval parasitoids were Habrobracon hebetor and Phanerotoma dentata (Hymenoptera: Braconidae). Population abundance of both hymenopteran wasps showed scarce representation percentages in the inspected fallen fruits with minor domination of Habrobracon population. The distribution percentages of both species exhibited slight increase towards the northern oases. The factors that may be responsible for distribution variance had been discussed.