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An eco-friendly electron beam irradiation (EBI) technology was used to assess the effect of EBI on the different development stages of Callosobruchus maculatus (F.) and Bactrocera zonata (Saunders). No adults emerged after 3-d-old eggs of C. maculatus were irradiated with 304.8 Gy of EBI, and no adults emerged from the F1 generation of larvae and pupae irradiated with 103.6 Gy. The adult stage of C. maculatus was the most tolerant of EBI, with a high dose (414.3 Gy) irradiation of the adult stage resulting in complete prevention of the F1 generation adult emergence. Large-scale tests confirmed that 414.3 Gy was an effective dose for the phytosanitary and security treatment for C. maculatus. An EBI dose of 414.3 Gy prevented B. zonata egg hatching. EBI doses of 304.8, 414.3, and 653.5 Gy prevented the development of first, second, and third larval instars to pupation, respectively. Using the criterion of adult emergence from the F1 generation, targeting the third larval stage, considered the most tolerant stage to EBI, a dose of 304.8 Gy was effective for quarantine and security treatment of B. zonata.

The current laboratory study investigates the effect of low doses of gamma irradiation range of (5-50 Gy) cesium cell- 137 on the different developmental stages eggs, 1st, 2nd , 3rd instars larvae and pupae of peach fruit fly, Bactrocera zonata. In addition to that the evaluation of phytosanitary irradiation dose on 3rd instar larvae and their effects on the biochemical quality of guava fruits were proven. The findings indicate that irradiation of eggs with dose 25Gy prevents adult emergence, while the dose 45Gy prevents pupation and the dose 50Gy prevents the hatchability of eggs. Moreover, exposure of larvae with the dose 50 Gy resulted in 98.5, 91 and 86 % mortality for the 1st, 2nd and 3rd instars larvae, respectively. No adult emergence was reported in 1st, 2nd and 3rd instars at the dose level 30, 35 and 45 Gy, respectively. The 3rd instar larvae appeared to be the most tolerant stage to radiation treatment than the 2nd and 1st larval instars. When adult emergence was used as a criterion for determination of the effective irradiation dose, 50 Gy was adopted for phytosanitary irradiation dose for B. zonata. Large scale confirmatory tests were applied to 25,000 3rd instar larvae of B. zonata in guava fruits resulting in non- F1 adults’ production with a confidence level of 91.8%. In conclusion, the irradiation dose of 50 Gy induces the inhibition of adult emergence of 3rd instar larvae and is suggested as a possible minimum dose for phytosanitary treatment of B. zonata fruit fly without causing significant effect (p ≤ 0.05) on some biochemical characteristics of guava fruits.

Purpose Combining gamma irradiation and nanotechnology has become one of the most promising new approaches for area-wide (AW) pest management in recent years. The laboratory trials were conducted to determine the combining effects of BT-AgNPs and gamma irradiation for controlling P. gossypiella. Radio-sensitivity of male pupae at different doses of gamma radiation and the effectiveness of biosynthesized silver nanoparticles using Bacillus thuringiensis on larval instar were assayed. Additionally, the ultrastructure changes on the alimentary canal of 4th instar larvae were studied to evaluate the impact of the combined approach at a cellular level. Materials and methods Laboratory- rearing technique was used for rearing Pectinophora gossypiella. The irradiation process was achieved at Co60 - Gamma Chamber (4000 A). Alanine dosimeters were used for measuring the average absorbed dose and dose mapping. Preparation of Silver nanoparticles (AgNPs) using Bacillus thuringiensis (Bt) and their characterization has been investigated. The treated 4th instar larvae by gamma irradiation or ∕and BT-AgNPs were dissected under the stereo microscope. The alimentary canal was obtained anatomically and Transmission Electron Microscope) was used in examining the stained sections. Results Based on the nonhatching eggs produced by irradiated males' pupae, the values of effective doses were calculated. The effective doses ranged from 16 to 291 Gy for the ED25 - ED75. The sterility index reached 74.1% when irradiated with males by 291 Gy crossed with nonirradiated females and the adult emergence decreased to be 35.3%. The insecticidal potential of Bt-AgNPs on the 2nd and 4th larval instars was dose-dependent and its LC50 toxicity value was 0. 3 and 0. 4 mg/ml, respectively. The lethal concentration LC50 of the 2nd instar larvae increased the larval and pupal mortality to 55% and 44.4%, respectively, and reduced the adult emergence to be 55.6%. The combining effects of Bt-AgNPs with 291 Gy induced 100% pupae mortality and there was no adult emergence in F1 generation. Such effects also severed the ultrastructure deformity of the midgut of the 4th instar larvae after the two-day post-treatment. Conclusions The combining effects are recommended as an effective IPM program to control P. gossypiella by releasing sterile males (derived from pupae irradiated with 291 Gy) crossing with the normal females in the field, and reducing the fertility of the population to 31.2%. Subsequently, the resulted larvae treated with LC50 of Bt-AgNPs prevented the adult emergence and stopped the life cycle of P. gossypiella.

Irradiation is a quarantine treatment option for stored product pests. In the present studies, we try to investigate the effect of low gamma irradiation doses in the range of 20–300 Gy on the different developmental stages of Rhyzopertha dominica in wheat grains. It was found that no adults emerged after irradiation of eggs, larvae, and pupae at 140, 240, and 260 Gy, respectively. Treatment of adult weevils at the radiation dose of 180 Gy resulted in 71.33% mortality after 14 days post-treatment and there was no adult emergence in the F1 generation. When the adult emergence of the F1 generation was used for the measuring effective irradiation dose and phytosanitary efficacy, 280 Gy was required for quarantine security of wheat weevils. The comet assay serves to verify the DNA damage induced by the phytosanitary irradiation dose, 280 Gy on the R. dominica, and wheat grains. DNA damage was measured as the percentage of comet tail DNA. A significant linear increase in DNA damage was observed in the irradiated adult stage of R. dominica but there is no DNA damage in the wheat grains. Also, the wheat grains viability (in terms of wheat germination) was not affected by the dose level, 280 Gy. Thus, an irradiation dose of 280 Gy is recommended as an effective phytosanitary irradiation dose for quarantine security to control lesser grain borer.

Irradiation is a physical, environmentally friendly treatment which does not leave any residues in the product. It is increasingly used as an alternative to methyl bromide and other chemical fumigants for disinfestation of insect pest in stored grains. In this research, we try to evaluate the effect of low gamma irradiation doses in the range of 50–1200 Gy on the different stages of Callosobruchus maculatus. It was found that no adults emerged after irradiation of eggs at 450 Gy. No emerging adults (F1 generation) have been shown when larvae or pupae were exposed to 650 Gy. Also, no emerging adult has been shown from the parental C. maculatus adults irradiated with 650 Gy. When suppression of F1 generation was used for the measuring effective irradiation dose and phytosanitary efficacy, 650 Gy was required for disinfestation of cowpea seed weevils. The irradiation dose level of 650 Gy was used for the large-scale confirmatory tests applied to 27,754 adults of C. maculatus in cowpea seeds resulting in non F1 adults' production with a confidence level of 93.77%. All the physical and chemical characteristics of cowpea seeds were non-significantly (P ≤ 0.05) affected by the irradiation dose of 650 Gy. Meanwhile, this irradiation dose very slightly reduced the microbial load of cowpea seeds. We recommend the generic dose 650 Gy as the phytosanitary irradiation dose for the cowpea seed weevil.

The study was conducted in order to assess the impact of gamma radiation on the different development stages of peach fruit fly, Bactrocera zonata, and to evaluate the influence of irradiation treatment on the physical, chemical, sensorial and microbiological qualities of pomegranate fruits. Pomegranate fruits were artificially infected with eggs and the 1st, 2nd and 3rd instar larvae of B. zonata and treated with different irradiation doses in the range of 50–400 Gy. The results indicated that no emerging adults were seen when eggs had been exposed to 100 Gy. The 3rd instar larva appeared to be the most tolerant stage to radiation treatment than the 2nd instar larva. Radiation treatment with 350 Gy resulted in 100% mortality in the 3rd instar larva. When adult emergence was used as criterion for measuring the effective irradiation dose, 150 Gy was required for disinfestation of the 3rd instar larva of B. zonata. Irradiation treatment of pupae either 3-or 7- days olds with 300 Gy prevented adult emergence. The irradiation dose level of 150 Gy used for the large – scale confirmatory tests was applied to 17,000 3rd instar larvae of B. zonata in pomegranate fruits resulting in non F1 adults’ production with confidence level of 81.7%. It could be conclude that the irradiation dose of 150 Gy prevented adult emergence from infested pomegranate fruits without causing significant (p ≤ 0.05) effect on the quality characteristics of the pomegranate fruits.

Combining gamma irradiation and nanotechnology has become one of the most promising new approaches for area-wide (AW) pest management in recent years. The laboratory trials were conducted to determine the combining effects ofLaboratory- rearing technique was used for rearingBased on the nonhatching eggs produced by irradiated males' pupae, the values of effective doses were calculated. The effective doses ranged from 16 to 291 Gy for the EDThe combining effects are recommended as an effective IPM program to control

The present study aimed at evaluating the effect of lethal doses of gamma radiation (LD25, LD50 and LD75) on reproductive potential of females resulted from irradiated pupae, and the latent...

The current study evaluated the effect of electromagnetic radiation on the stomach cells of honey bee foragers. Normal cells are distinguished by different heights with well-developed muscular layers and an internal plasma membrane. During our study we used a mobile phone (Samsung F400) with the provider Vodafone, Egypt and a carrier frequency range of 900–1900 MHz. Bee workers were captured while returning from the field to the hive (about 23 days old). When honey bee foragers were exposed to mobile phone radiation for 20 min, the stomach cells were completely decayed. With regard to stomach cells which were exposed for 10 min, some parts of the cells were completely lysed, appeared as a thin tubular-like layer, or as compact mass, and the internal plasma membranes were not clear. Also, the chemical element composition of the cells exposed to 10 min of mobile phone radiation was affected as follows: Mg, Ca, Zn and Fe elements were significantly increased, while sulphate elements were significantly decreased. The current study demonstrated that mobile phone radiation is harmful to honey bee stomach cells, and we recommend limiting the use of mobile phones near hives.

Irradiation is a physical, environmentally friendly treatment which does not leave any residues in the product. It is increasingly used as an alternative to methyl bromide and other chemical fumigants for disinfestation of insect pest in stored grains. In this research, we try to evaluate the effect of low gamma irradiation doses in the range of 50-1200 Gy on the different stages of Callosobruchus maculatus. It was found that no adults emerged after irradiation of eggs at 450 Gy. No emerging adults (F1 generation) have been shown when larvae or pupae were exposed to 650 Gy. Also, no emerging adult has been shown from the parental C. maculatus adults irradiated with 650 Gy. When suppression of F1 generation was used for the measuring effective irradiation dose and phytosanitary efficacy, 650 Gy was required for disinfestation of cowpea seed weevils. The irradiation dose level of 650 Gy was used for the large-scale confirmatory tests applied to 27,754 adults of C. maculatus in cowpea seeds resulting in non F1 adults' production with a confidence level of 93.77%. All the physical and chemical characteristics of cowpea seeds were non-significantly (P ≤ 0.05) affected by the irradiation dose of 650 Gy. Meanwhile, this irradiation dose very slightly reduced the microbial load of cowpea seeds. We recommend the generic dose 650 Gy as the phytosanitary irradiation dose for the cowpea seed weevil.

In the present study, gamma radiation effects on the reproductive potential of the mosquito, Culex pipiens and its role in the transmission of the Hepatitis C Virus (HCV) were investigated. The susceptibility of female, Culex pipiens mosquitoes to gamma irradiation was carried out by exposed full grown pupae to doses 0, 20, 40, 60 Gy. The lethal doses were calculated, as the doses of gamma radiation increased, a progressive increase in the non- hatched eggs percentage. The viral load at mouth parts, in mid-gut and salivary gland, was detected in the irradiated females with LD75 (60 Gy) and non-irradiated using RT-PCR relatively at time 60 min., 5 and 13 days and tested in the mentioned position. Viral load in irradiated Culex pipiens that fed on an infected blood with a viral load 1.2 x 106IU/ml %was decreased by time from 6.0782 x 104 IU/ML% at zero time into 2.399 x 103 IU/ML% after 60 min. post-infection at the mouth parts. Also, the viral load decreased by time in the mid-gut from 2.63575 x 105 IU/ML% at zero time into 3.969 x 103 IU/ML% after 5 days post-infection, while HCV was not detected in the salivary glands. The current results indicated that the mechanical transmission through mouth parts in irradiated and non-irradiated Culex pipiens mosquitoes is plausible while the biological transmission did not occur.

Laboratory male pupae of Culex pipiens were exposed to 23, 41, 74 and 128 Gy doses of gamma radiation according to the LD 25, LD 50 , LD 75 and LD 90 calculation, respectively. The inherited deleterious effects of gamma radiation were observed in the F 1 , F 2 and F 3 generations. Levels of sterility index in the F 1 and F 2 were higher than those of untreated control but in the F 3 generation there was a semi-sterility compared with the control. Ultrastructure of normal males' testes of C . pipiens was studied using transmission electron microscopy. Histopathological responses were observed in the irradiated testes of C . pipiens . Gamma radiation had greatly affected the testes, such as (i) rupture, necrosis, degeneration and small vacuoles were reported in the testicular wall (ii) an abnormal distribution of the developmental stages of spermatogonia and spermatocytes leading to a general decrease in the rate of spermatogenesis; and (iii) deformity of sperm inhibitting the movements and the fertility of the sperm led to the decrease in the reproductive potential of C . pipiens . Consequently, these radiation doses are consistent with those used in the already established Sterile Insect Technique (SIT) programmes against Culex pipiens .

Wheat flour samples were artificially infested with Corcyra cephalonica, Ephestia kuehniella, Tribolium confusum (separately) and with the three insect populations together. The effect of insects’ infestation on wheat flour quantity and quality loss, fungal contamination and presence of mycotoxins was studied after two months of storage (25±2C and 65%RH). Wheat flour infested with insects was sieved into two portions (sieved and residual flour) after insects populations have been recorded. The results revealed radical changes in weight loss, population density of insects, nutritional composition, interaction between insects and fungal contamination in the flour samples. The maximum residual flour loss was recorded by C. ceplalonica followed by E. kuehniella while the minimum residual loss was induced by T. confusum. The flour consumption by the tested insects may be arranged in descending order as follows: three insects tested together > C. cephalonica > T. confusum > E. kuehniella. There was a significant correlation between the amount of flour consumed and insect population. Also, there was a significant increase in the total protein contents and decrease in the monosaccharaides and disaccharides in all infested sieved and residual flour samples tested. The average log total molds count in control flour samples was 1.28, while the average log of insect infested flour samples ranged from 2.36 to 4.34. Seven to ten fungal species belonging to five genera (Aspergillus, Penicillium, Cladosporium, Eurotium and Emercilla) were isolated from control and infested flour samples. Many fungal species were isolated from infested flour, but most of them belong to Aspergillus and Penicillium. Aflatoxins B1, B2 were detected in all flour samples, but at different levels. Ochratoxin A was not detected in the control samples and C. cephalonica flour samples while it was detected in flour samples infested with the other treatment. © 2016 Friends Science Publishers

External morphology of males' hind legs of Spodoptera littoralis subjected to thermal treatment (33 °C and 37 °C) or/and irradiated with substerilizing doses of gamma radiation (75, 100 and 150 Gy) were studied using scanning electron microscopy (SEM) in the parental generation. Five types of sensilla have been distinguished; three types of trichoid sensilla (T1,T2 and T3), sensilla basiconica and sensilla auricillica, which are considered as olfactory chemoreceptors. Moreover, sensilla chaetica are contact chemoreceptors, whereas sensilla styloconica are thermo–hygro/gustatory mechanoreceptors. The impact of thermal treatment or/and gamma irradiation reflect a clear morphological change in S. littoralis legs'sensilla, claws, spurs and scales. Otherwise, the degree of deformity was thermal and dose dependent, as it increased with an increase of the degree of temperature and dose of irradiation applied. Substerilizing doses 75 and 100 Gy, either alone or combined with thermal treatment 33 °C, have low undesirable effects on the hind legs with successful mobility or courtship behavior. Consequently, synergistic effect of gamma radiation and thermal stress induced successful application in the integrated pest management program for controlling S. littoralis.

Molecular resistance of Spodoptera littoralis to gamma radiation and/or fungal pathogenic Beauveria bassiana via malate dehydrogenase (Mdhs) and peroxidase (Pxs) isozymes by using native- polyacrylamide gel electrophoresis was the aim of this study. Under laboratory conditions, the pathogenicity of B. bassiana against 2nd instar larvae of S. littoralis was studied. Mortality percentage increased with the time period of fungal incubation. The LC50 value of B. bassiana was (0.4×105 spore/ml) after 5 days of treatment. Analysis of gel electrophoresis revealed 4 Mdhs and 6Pxs isozyme in the 6th instar larvae of S. littoralis. Tissue extracts have been assigned according to their mobility. Gamma rays revealed disorders of the Mdhs and Pxs isozyme expression and density. Mdh1band intensity was decreased at 100 and150 Gy, while Mdh2 band intensity was decreased only at 100 Gy. Furthermore, Px1, Px2 and Px3 isozyme intensity was decreased at 100 and 150 Gy. S. littoralis exposed to 50 Gy showed resistance to radiation effects and an increase in Pxs and Mdhs bands intensity. Through the course of infection by LC50 value of B. bassiana, Mdhs and Pxs were affected and disturbed. Combined treatment of 100 Gy and B. bassiana showed synergistic effects causing marked disturbance and decrease in the isozyme pattern intensity of Mdhs and Pxs or missing Px3. However, Mdhs and Pxs isozymes intensity and expression were greatly affected after 96 h. That reflects the depression in the resistance of S. littoralis and explains the rate of mortality after 5 days post treatment.

The present study aimed to evaluate the inherited deleterious effects and protein response of Musca domestica to LD50 of gamma irradiation through three generations at different cross combinations (irradiated female (IF) × irradiated male (IM), unirradiated female (UIF) × irradiated male, and irradiated female × unirradiated male (UIM)). Gamma radiation induced a significant effect on the reproductive potential of M. domestica through the first three generations, where the sterility index was higher than those of the untreated control, especially in F1 and F2 generations. The great inherited deleterious effects occurred when IM × IF and when IM × UIF indicating that the male of M. domestica is more radiosensitive than the female. The electrophoretic separation of protein bands in the third larval instar of M. domestica resulted from different matings (irradiated and unirradiated males and females) vs control was investigated in the present study. The control larvae recorded the highest number of protein bands (27), while the larvae resulted from crossing of UIF × IM (LD50 = 5 Gy) contained the lowest number of protein bands (14). However, the number of protein bands in larvae resulted from crossing of IF × UIM (LD50 = 7 Gy) was 24 bands also the number of bands resulted from crossing IF × IM (LD50 = 4 Gy) was 21 bands. In addition, the results showed that the type of mating affects the distribution of protein bands, where some protein bands appeared and others disappeared in third larval instar resulted from the different irradiated and unirradiated males and females. These results may indicate that males of M. domestica are more radio sensitive than females where the lowest number of bands was separated in larvae resulted from IM × UIF. Consequently, these radiation doses are recommended for the establishment of Male Sterile Insect Technique (SIT) programmes against M. domestica.

Scanning electron microscopy (SEM) allowed observing Beauveria bassiana and Metarhizium anisopliae adhesion and penetration structure on Agrotis ipsilon larvae. SEM of A. ipsilon larvae treated with the Lc50 of the fungus, B. bassiana revealed adhesion and penetration structures in the infected larvae. Growth of the fungus on the infected larvae and signs of hyphal penetration of insect cuticle as well as proliferation of the cuticle were also appearing. On the other hand, the fungus, M. anisopliae as declared by SEM showed a dense network together and cause the green spores on the insect cuticle. Also, SEM allowed observing the spores and hyphae of the fungus in the body cavity of infected larvae. Scanning electron microscopy is allowed tool to observe the mode of action of entomopathogenic fungi and to observe how they are able to colonize and infect the host.