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The present study evaluated the efficacy of X-ray irradiation for the sterilization of Ceratitis capitata. Pupae were exposed to doses of 0 (control), 60.7, 137, 156.9, 237.7, 300.59 and 344.46 Gy to determine which dose would not affect viability of irradiated fruit flies but would result in their sterilization. Doses of 60.7 and 137 Gy were suitable as males emerging from irradiated 7-day-old pupae were 100% sterile but were otherwise viable. Light and transmission electron microscopy were used to examine the structure of normal and treated male C. capitata testes. The testes of males originating from non-irradiated pupae of C. capitata consist of a single long follicle that looks like a sac and is full of germ cells at different stages of development. In testes of males originating from irradiated pupae, the presence of lysosomes, many vacuoles, and irregular distribution of spermatogonia and spermatocytes, led to an overall slowed rate of spermatogenesis. Apparent degeneration and abnormalities of the sperms resulted in the production of non-functional sperm or to a reduction in sperm production. This study concluded that X-ray is an alternative irradiation method for the sterile insect technique used to control Mediterranean fruit fly populations. [ABSTRACT FROM AUTHOR]

Ceratitis capitata is considered one of the world’s most destructive pests. Medflies can infest over 300 species of fruit plants, adapt to a variety of climate zones and have a high invasive potential. Medfly can target economically valuable fruit, resulting in significant economic losses estimated to be in the billions of dollars per year. This study aimed to investigate the effect of X-ray irradiation on the female ovary of Ceratitis capitata (resulting from irradiated pupae) in comparison to a normal female ovary of the same age. The structure of normal and treated female ovaries of Ceratitis capitata was studied using light and transmission electron microscopy. The female reproductive system of Ceratitis capitata is composed of paired lateral ovaries. Each ovary consists of polytrophic meroistic ovarioles formed by a terminal filament, a germarium and a vitellarium. The female ovaries were greatly affected by X-ray irradiation because of the appearance of abnormal shape and size of egg chambers, degeneration of nurse cells and their nucleus, the nucleus of follicular epithelium appear devoid of chromatin materials, presence of lysosomes and myeloid bodies, the oocytes appear devoid of yolk granules and its nucleus. The results of this study show that X-ray radiation technology has a clear effect on C. capitata and could be considered an effective and safe method to control medflies populations. [ABSTRACT FROM AUTHOR]

Five days old B. zonata pupae were subjected to gamma irradiation at doses of 25, 30, 35 and 50 Gray (Gy), from a Cesium cell-137. The resulting males were crossed with untreated females. The mean total number of eggs laid by the female (fecundity) is significantly decreased (P < 0.05) with the dose increase. The viability (hatching percent) of deposited eggs at all three doses showed a significant decrease (P < 0.05). Laid eggs by females mated with males resulted from pupae treated with gamma radiation with doses 25,30,35 and 50 Gy were processed for histological studies. First cleavage nuclei were observed about 2 hours pop and the blastoderm formation occur about 4 hours pop in control. At 8 hours pop, the blastoderm thickness forming the germ band. In about 24 hours pop brain appeared. The germ band Segmentation and formation of different organs started about 36hrs POP. Doses of 25 and 30 caused a failure of cleavage nuclei to migrate toward the periphery to form the blastoderm. While other embryos were blocked at germ band formation. In doses of 35 and 50 Gy, massive cellular and tissue damage to the embryos was reported. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. 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. 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. 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. [ABSTRACT FROM AUTHOR]

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 900-1900MHz. 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 20min, 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 10min 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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) x irradiated male (IM), unirradiated female (UIF) x irradiated male, and irradiated female x 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 x IF and when IM x UIF indicating that the male ofM. 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 x 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 x UIM (LD50 = 7 Gy) was 24 bands also the number of bands resulted from crossing IF x 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 x UIF. Consequently, these radiation doses are recommended for the establishment of Male Sterile Insect Technique (SIT) programmes against M. domestica. [ABSTRACT FROM AUTHOR]

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 (0.4x105 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. [ABSTRACT FROM AUTHOR]

Red palm weevil, Rhynchophorous ferrugineus (Olivier, 1790), (Coleoptera: Curculionidae) is the most dangerous pest for date palms in the Middle East, especially the Arab Gulf countries. The proboscis sensilla in males are studied by using Scanning Electron Microscopy (SEM) to assess the effect of gamma irradiation with different doses. Eight types of sensilla have been observed; four types of coeloconic sensilla (I, II, III, IV) are distributed on the lateral and frontal cuticular surface of the proboscis with a chemoreceptors function. Trichodea sensilla (I, II) and coeloconic sensilla (V) are concentrated on the dorsal surface of proboscis and are arranged in two rows to serve an olfactory and mechanosensory function. A very few number of squamiform sensilla (I) are scattered on the anterior-lateral side of proboscis to perform a mechanoreception function. Such malformation that gave rise to morphological structures of sensilla after exposing the pupae to the doses 10, 15, and 20 gray of gamma radiation are discussed. Irradiation with dose 10 Gy had a slight effect on the different types of sensilla as compared to the control, whereas at the radiation doses (15, 20 Gy) percentage of malformation are increased. The information gained from this study shows that the doses 15, 20 Gy have affected most types of sensilla and that the coeloconic sensilla (IV) are the only type that is not affected by any dose of irradiation. [ABSTRACT FROM AUTHOR]

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±2oC 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. [ABSTRACT FROM AUTHOR]

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±2oC 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. [ABSTRACT FROM AUTHOR]

Integrated pest control of the cotton leaf worm, Spodoptera littoralis (Boisd.) using gamma radiation and/or entomopathogenic fungus, Metarhizium anisopliae is a complex incident of different aspects, such as reproductive capacity, cellular immune system and biochemical challenges. Pathogenicity of M. anisopliae against 2nd instar larvae of S. littoralis was studied under laboratory conditions. Mortality percentage increased with time period of fungal incubation in insects. LC50 values of M. anisopliae was (8x108 spore/ml) after 5 days of treatment. The 6th instar larvae of S. littoralis, which resulted from injection with LC50 of M. anisopliae or exposure to gamma radiation, showed changes in hematological patterns. Exposure to 100 Gy of gamma radiation markedly decreased (THC)/mm³ and the percentage of all immune cell types (Pl, Gr, Sph, Adip, Cys and Oen) during the course of examination. M. anisopliae changed haemolymph properties in two stages: the first stage, in the first day after infection, there was an in crease in the (THC)/mm³ and in the percentage of all immune cell types, on the other hand, the second stage was at the second, third and fourth days post treatment as it showed a significant decrease in the THC and the percentage of all immune cell types. Combination of gamma rays and M. anisopliae also showed the same behavior, with marked significant decrease than that induced by each of M. anisopliae or gamma radiation alone. Analysis of haemolymph protein profile using gel electrophoresis showed fourteen differentially expressed proteins ranging from 9.6 - 116.2 KDa. Gamma-irradiation and infection with M. anisopliae markedly affected protein profiles and can be manipulated in the proteins of molecular weight in the range of 56.9-82.6 KDs of prophenoloxidases and phenoloxidases. In conclusion, the results revealed that gamma radiation and M. anisopliae infection greatly affect cellular immune system and protein expression. So, it may result into insect death due to disturbance in the immune system and proteins. [ABSTRACT FROM AUTHOR]

Chrysomya albiceps play a major role as a mechanical vector for plentiful pathogens to humans and animals such as bacteria, viruses, and helminths, as well as causing myiasis in animals. The present study aimed at investigating the effect of gamma radiation on the reproductive potential and embryonic lethality of C. albiceps.Results showed that the number of eggs laid by C. albiceps females resulted from pupae irradiated with different doses of gamma radiation decreased as the dose increased. Also, the nonhatching eggs %was found to be dose-dependent i.e., increased as the dose of the gamma irradiation used increased.The highest reduction in the number of eggs occurred at high doses (10 and 15 Gy) when irradiated females were crossed with non-irradiated males. Non-hatching egg % increased to record 76.6 and 66.8 at 15 and 10 Gy when irradiated females crossed with irradiated males. Gamma radiation resulted in a progressive increase in the sterility % of C. albicepsfemales as compared with the untreated group. Complete sterility (100.0%) was attained by 20 Gy for all groups. The sterility index was recorded at 96.3% when irradiated females crossed with non-irradiated males.In addition, gamma radiation-induced a progressive increase in egg lethality giving an estimated LD50 value of 9.3598 Gy when non-irradiated females mated with irradiated males, compared with 10.6257 Gy for egglethality laid by irradiated females mated with non-irradiated males. However, the LD50 value was 3.603 Gy when both males and females were irradiated, respectively. Generally, C. albiceps females were more radiosensitive than their male counterparts. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]