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The success and sustainability of entomopathogens in insect control depend on their stress potential and ability to modulate certain physiological aspects of their insect hosts. In the present study, newly moulted fourth instars of Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) were incubated for 24 h with the median lethal dose (LD 50) of Steinernema riobrave, Heterorhabditis bacteriophora, or Beauveria bassiana to determine their effects on certain metabolic activities and nutritional physiology compared to those of uninfected (control) larvae. Infection decreased total protein, lipid, and carbohydrate contents. Carbohydrase activity was found to be pathogen and enzyme dependent, with S. riobrave and H. bacteriophora infection increasing amylase, invertase, and trehalase activities. Beauveria bassiana infection decreased amylase and invertase activities but increased that of trehalase. Infection with the three pathogens also enhanced phosphatase activity. All pathogens reduced transaminase activity. Changes in the nutritional indices varied not only with the variation in the candidate entomopathogen and surviving instar but also with the variation in the age of the same instar, with a profound change in late last instars (3-day-old sixth instars). The link between the metabolic activities and nutritional indices was discussed. Overall, the entomopathogen-host interaction appears to be primarily nutritional. The pleiotropic effects of the median lethal infections on the insect pest might eventually help in the biological control potential of the entomopathogens tested.

The red palm weevil, Rhynchophorus ferrugineus, is the biggest pest of various palm species. The aim of this study was to evaluate the impact of the essential oils of purslane, mustard and castor (bulk and nano) on R. ferrugineus and to evaluate the oviposition deterrent effect to prevent new infestations. Prepared concentrations of essential oils (bulk and nano) were tested for their impact on R. ferrugineus larvae, pupae and adults. The most effective oil was purslane oil (bulk and nano), followed by mustard and the least effective was castor. The percent mortality of larvae was 75.2, 45.3 and 17.9% (bulk phase) and 92.5, 84.4 and 65.5% (nano phase) in purslane, mustard and castor, respectively, when treated with the high concentration. The percent mortality of adults was 67.2, 40.0 and 15.6% (bulk phase) and 83.5, 72.9 and 60.0% (nano phase) in purslane, mustard and castor, respectively, when treated with the high concentration. The number of eggs laid decreased with increasing concentration of the tested oils. Purslane essential oil showed good impact on R. ferrugineus larvae and adults followed by mustard and castor oils as bulk and as nano.

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Background: Rhynchophorus ferrugineus is one of the most severe pests on palm species, including date palms In Asia. Purpose: The purpose of the current study is to evaluate the virulence of bio efficacy of nano-particle of entomopathogenic fungi and entomopathogenic bacteria on red palm weevil, Rhynchophorus ferrugineus. Methods: Prepare concentrations of Fungal Spores and Silver Nano Particles were prepared from Metarhizium anisopliae, Beauveria bassiana, Verticillium lecanii and B. thuringiensis, B. subtilis. Results: M. anisopliae was the highest % mortality (90%), (95%) and (77%) against eggs, larvae and adults of R. ferrugineus, respectively when treated with bio synthesized or with fungal spores after seven days from treatment and the lowest % mortality was recorded when treated with V. lecanii.Three concentrations, (10 3 , 10 4 , and 10 5 CFU/mL), formulated as bacterial suspensions and bio-synthesized silver nanoparticles, (Ag NPs) were evaluated for their ability to inhibit egg hatch. The 10 5 CFU/mL concentration, both as a bacterial suspension and formulated as Ag NPs, was tested for efficacy against 10 day-old larvae and adults. Egg hatch was significantly inhibited by all concentrations and formulations of B. subtilis and B. thuringiensis, and exhibited lethal concentrations for 50% mortality (LC50) of 3.45 X 10 3 and 6.73 X 10 4 CFU/mL, respectively. The percent mortality of larvae six days after treatment was 85% and 77% for B. thuringiensis and B. subtilis Ag NPs, respectively. The percent mortality of adults six days after treatment was 75% and 67% for B. thuringiensis and B. subtilis Ag NPs, respectively.Conclusion: The bio control efficiency of Ag NPs synthesized by five isolates of M. anisopliae, B. bassiana, Bio Magic, Bio Power and Bio Catch on R. ferrugineus was proven to be effective through bio assay by spore suspension and bio synthesized silver nanoparticles. M. anisopliae had the highest efficiency on R. ferrugineus and was more effective than B. bassiana, Bio Magic, Bio Power and Bio Catch.B. thuringiensis inhibited the hatching of R. ferrugineus, it is the highly effect than B. subtilis against all stages (eggs, Larvae and Adults) of R. ferrugineus. B. thuringiensis is the highly effect as a bio synthesized Ag NPs against larvae and adults of R. ferrugineus than bacterial suspensions. B. thuringiensis is the highest effect than B. subtilis as well bacterial suspensions or as a bio synthesized Ag NPs. KeywordsVirulence, Nano-particle, entomopathogenic fungi, entomopathogenic bacteria, Rhynchophorus ferrugineus.To cite this article: ABDEL-RAHEEM M.A., REYAD NF, ALGHAMDI HA. Virulence of Nano -Particle preparation of Entomopathogenic fungi and Entomopathogenic Bacteria against red palm weevil Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae).

The red palm weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae), is one of the most severe pests of date palms. The study aimed to evaluate the virulence of fungal spores and silver Nano-particles from entomopathogenic fungi (EPF) on R. ferrugineus under laboratory conditions. Concentrations of the fungal spores and the silver Nano-particles were prepared from Metarhizium anisopliae, Beauveria bassiana, and Verticillium lecanii. The results showed that the 3 EPF achieved 70-90% mortality rates within 7 days in egg stage. M. anisopliae and B. bassiana were the most effective ones. The isolate V. lecanii was tested on eggs, larvae, and adults. Spores of M. anisopliae increased eggs' mortality and reduced their hatchability. The egg mortality rate was 80% higher than the control. Seventy-percent adult mortality rate was achieved in 7 days, when treated with M. anisopliae, 60% with B. bassiana, and 53% with V. lecanii. M. anisopliae was more effective on R. ferrugineus than B. bassiana.

In the present study, the infectivity of the four entomopathogenic nematodes, Steinernema glaseri, Steinernema carpocapsae, Steinernema riobrave and Steinernema scarptasci on the earwig. Labidura riparia (Nymph and adult) was studied under laboratory conditions. S. carpocapsae exhibited a high virulence against the nymphs of L.riparia. On the other hand, S. scarptasci showed a higher mortality rate to the L.riparia adults. The highest numbers of juveniles emerging from infected insects (adult and nymphs) by nematode species S. carpocapsae were 38750 Is/adult and 20750 IJs/nymph. Using SDS-polyacrylamide gel electrophoresis the whole body proteins fractionated into 19, 18, 13, and 15 bands when L.riparia adult were infected by S.glaseri, S. scarptasci, S. riobrave and S. carpocapsae ,respectively. The most obvious observation was the complete disappearance of the slow moving protein fractions (fractions number 14-17) in samples infected by S. riobrave. Also, fractions 16-17 also disappeared in samples infected by S. carpocapsae. On the other hand, the disappearance of some protein fractions was accompanied with appearance of new fractions in samples of infected insects, i.e., fractions 18 and 19 in S.glaseri-infected insects. Most of these new protein fractions were among the low molecular weight. The tested samples affected the molecular weight, band percentage and protein content of the whole body profile protein. These results suggested the tested four steinernematid species have side effect on the predacious insect L.riparia (adults and nymphs), penetrates to its haemocoel causing death 4-days post infection.

Climate change could profoundly affect the status of agricultural insect pests. This study is a predict of the two-spotted spider mite in potato and tomato cops annual generation peaks under current and expected future climate by using the relationship between the accumulated thermal heat units expressed as degreedays unit (DDU) and the population fluctuations. The results indicate the population of the predicate annual generation number and duration of T. urticae of tomato and potato crop under current and expected future climatic changes and their relationship with accumulated thermal units (degree-days units), at Beheira, Bani sweif and Sohag governorates. Under current climate mean generation numbers of T. urticae (10-12 and 12) and mean numbers days per generate (21-19 and 19) and mean degree-days units for T. urticae (170.7-170.9 and 167.4) at Beheira, Bani sweif and Sohag governorates, respectively were highly recorded compared with expected future climate in 2050s and 2100s. Meanwhile, future predicate in 2050s and 2100s, mean generation numbers (15-17 generation) were highly recorded, but mean degree-days units (165.2-172.3 unit) were highly recorded and days numbers per generate (14-17 days per generate) were less recorded compared with data of current climate, respectively.