Recently, the mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) was recorded as a new pest on tomato plants (Lycopersicon esculentum Mill) growing in Egypt. The mealybugs specimens were collected from tomato plants in the Qalyoubia governorate during summer season of 2014. The mealybug was identified as P. solenopsis based on the morphological characters and taxonomic key of this species. This study represents the first record of P. solenopsis as a new insect pest attacking tomato plants in Egypt

BACKGROUND The German cockroach, Blattella germanica, is one of the most severe pests of urban and rural areas. High‐throughput genetic screening approaches indicate that the olfactory system of this pest is extremely powerful because it has an extensive array of olfactory receptor genes compared with many other insect species. Several of these genes have been identified previously, but their functions have not yet been characterized. RESULTS This study describes the sequence of five transcriptomes of B. germanica adult male antennae, female antennae, maxillary palps, legs, and fifth‐instar nymph antennae to investigate expression patterns of odorant receptors (ORs). Approximately 90% of ORs were found to be the most highly expressed genes in adult or nymph antennae. Additionally, every OR requires an odorant co‐receptor (Orco) to become fully functional, and this was selected and successfully inhibited by injection of the corresponding double‐stranded (ds)RNA targeting the Orco. A strong RNA interference (RNAi) effect was observed in which > 75% of Orco messenger RNA (mRNA) was clearly suppressed after 72 h of treatment. Olfactory behavioral assays showed that Orco‐impaired B. germanica respond more slowly and show less attraction to one volatile sex pheromone and food resources compared with a control group. CONCLUSION The results show that Orco plays a pivotal role in both sex pheromone and food‐seeking olfactory processes, and provide an alternative genetic technique for controlling this urban pest species by olfactory disruption. © 2020 Society of Chemical Industry

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Solanaceous plants have a great economic impact in Egypt. These groups of plants include potatoes, tomatoes and eggplants. The new invasive pest of tomatoes, Tuta absoluta (Meyrick) causes the greatest crop losses which can range from 60 to 100%.After its detection in Egypt during the last half of 2009, it spread quickly to all provinces in the country. We aiming to propose a sustainable control program for this devastating pest. In this research we tested three groups of control agents. The first was microbial and natural, the second -plant extracts and the third -chemical insecticides. Our results showed that the impact of T. absoluta can be greatly reduced by the use of sustainable control measures represented by different insecticide groups. Bioassay experiments showed that this devastating pest can be controlled with some compounds that give high mortality rates. Of these compounds, spinosad and Beauveria bassiana, microbial control agents, followed by azadirachtin, gave the best results in controlling T. absoluta. Of the chemical insecticides, lambda-cyhalotrin was the most effective, followed by lufenuron and profenofos. In conclusion we encourage farmers to use microbial and natural control measures in combating the tomato leafminer, T. absoluta, in Integrated Pest Mangement (IPM) programs.

Schistosomiasis is one of the major communicable diseases of public health and socioeconomic importance in the developing world. It is a waterborne disease in which Biomphalaria alexandrina snails are known to be the intermediate molluscan host for Schistosoma mansoni: the causative agent of human intestinal schistosomiasis. Therefore, snail control is one of the cornerstones of schistosomiasis control programs. Several methods have been used to eliminate snail hosts. One of these methods is chemical molluscicides, which have undesirable effect to nontarget organisms. Consequently, the search for biologically derived molluscicides to complement the use of synthetic molluscicides is a top priority. In this concern, this study is the first to evaluate the molluscicidal potency of Cyanobacterial Phycocyanin (C-PC) as a virtually untapped source. Laboratory assessment of three freshwater Cyanobacterial strains: Anabaena oryzae SOS13, Nostoc muscorum SOS14, and Spirulina platensis SOS13-derived C-Phycocyanin as a biocontrol agent against freshwater mollusks; B. alexandrina snails were performed. Also, the safety of tested C-PC on nontarget organisms (Tilapia fish) was assessed. Results reveal that C-PC extracted from all tested Cyanobacteria strains showed a promising molluscicidal activity (the mortality rate was 100% at 100 μg/mL concentration). Out of the examined strains, A. oryzae SOS13 phycocyanin was found to be the most potent strain (LC and LC were 38.492 and 49.976 μg/mL, respectively). Moreover, C-PC extracts from all tested strains have been found to be safe to Tilapia fish as the survival rate was 100% at the effective molluscicidal concentrations. We can conclude that C-PC extracts are the first promising microbial biopesticides for the control of freshwater B. alexandrina snails.

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Different techniques were adopted for molecular characterization of several indigenous strains of Bacillus thuringiensis (Bt) previously isolated from Egyptian soil samples. These isolates show different toxicity levels against neonate larvae of both insect species; Spodoptera littoralis (Biosduval); and Helicoverpa armigera (Hübner). The parasporal crystals among the most potent isolates contained polypeptides of about 127 and 130 kDa. PCR screening for genes encoding different Cry genes was performed. The Cry 1 gene is the most abundant in these isolates (83.33%) among tested Cry-type genes, followed by Cry 1 gene subfamilies (Cry 1B and Cry 1C) with percentage of 38.88% and 77.77%, respectively. The tested isolates showed the presence of Cry 2A(a,b) gene, but not all of these isolates were positive for Cry 2 gene (55.55%). Only 27.77% and 16.66% of the tested isolates harbor Cry 4 and Cry 3 genes, respectively. All strains were negative in PCR assays for the Vip 3Aa1 gene. Moreover, DNA fingerprinting using RAPD-PCR was performed to detect the genetic similarities and dissimilarities among the different isolates and standard strains. Assessment of Bt diversity based on the combined analysis of their protein and RAPD-PCR banding patterns was performed. This study demonstrates that Bt strains isolated from Egyptian soil samples can be distinguished and identified on the basis of the distribution of Cry-type genes and RAPD fingerprints.

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