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Chemical communication is an essential item for insects’ survivals that qualify them to adapt their behavior depending on the surrounding environment. Semiochemicals defined as informative molecules (M) mainly play an important role that conveys specific chemical messages between insect and insect and plant and insect. Olfaction mechanism in insects is a key point of chemical communication between the same and different insect species. Discrimination of various odors through the olfaction system depends only on the evolutionary pressures of the molecules which stimulate the development of specific binding proteins (BPs) and specific receptor sites present on individual chemosensory neurons. Pheromones are defined as species-specific chemical signals which enable communication between life-forms of the same species. Recently, semiochemicals become as alternative or complementary components to insecticide approaches in integrated pest management (IPM) strategies. Pheromones are secreted by insects causing a specific reaction, for example, either a definite behavior or a developmental process. Pheromones have been classified into eight various types: aggregation pheromones, alarm pheromones, oviposition-deterrent pheromones, home recognition pheromones, sex pheromones, trail pheromones, recruitment pheromones, and royal pheromones. Pheromones are promising and can be used singly or in integration with other control strategies for monitoring and controlling insect pests in agricultural systems.

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.

The present review provides a perspective angle on the historical and cutting-edge strategies of remote sensing techniques and its applications, especially for insect pest and plant disease management. Remote sensing depends on measuring, recording, and processing the electromagnetic radiation reflected and emitted from the ground target. Remote sensing applications depend on the spectral behavior of living organisms. Today, remote sensing is used as an effective tool for the detection, forecasting, and management of insect pests and plant diseases on different fruit orchards and crops. The main objectives of these applications were to collate data that help in decision-making for insect pest management and decreasing the environmental pollution of chemical pesticides. Airborne remote sensing has been a promising and useful tool for insect pest management and weed detection. Furthermore, remote sensing using satellite information proved to be a promising tool in forecasting and monitoring the distribution of locust species. It has also been used to help farmers in the early detection of mite infestation in cotton fields using multi-spectral systems, which depend on color changes in canopy semblance over time. Remote sensing can provide fast and accurate forecasting of targeted insect pests and subsequently minimizing pest damage and the management costs.

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

The cigarette beetle, Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae), is an important stored-product insect pest. In the present study, the external morphologies and distribution of the sensilla on the antenna and mouthparts of L. serricorne were described following scanning electron microscopy with the aim of understanding the behavioral mechanisms of this insect pest. On the antennae, various sensilla types were identified: Bohm bristles, three basiconic sensillum subtypes, two chaetica sensillum subtypes, three styloconic sensillum subtypes, as well as trichodea, capitulum, and campaniform sensilla. Interestingly, campaniform sensilla and two subtypes of styloconic sensilla (St1 and St2) were reported for the first time on L. serricorne antennae. The mouthparts of L. serricorne carried six different sensory structures including chaetica, basiconic, styloconic, auricillic, and trichodea sensilla, as well as long macrotubercles. Two subtypes of chaetica sensilla were recorded on the labrum, mandibles, and maxillary and labial palpi. A basiconic sensillum subtype (BS3) was distributed on the galea and lacinia, while subtype BS2 was also found on the lacinia along with long fan-like macrotubercles, which are hypothesized to help clean the area of the preoral cavity directly below the base of the labrum. Auricillic sensilla were also found on the galea. The labial palpi showed three subtypes of basiconic sensilla (BS3, BS4, BS5), whereas the maxillary palpi bears BS4, and BS5. Styloconic sensilla were also found at the top of the maxillary and labial palpi. Blunt basiconic (BS6) and trichodea sensilla were found on a tongue-shaped structure (pharynx) situated entirely at the midline of the preoral cavity. These findings improve understanding of the sensory perception of an important insect pest and could help to develop suitable control methods.

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.

This study has two main approaches. First, it exploits the susceptibility of tomato cultivars as a prophylactic measure to detect auto resistance characters of the tested tomato varieties against Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae). Secondly, it evaluates the efficacy of different bio-rational insecticides against B. tabaci under greenhouse conditions. The results exhibited a special significance in B. tabaci infestation suitability between the two tomato varieties with a high infestation significance found in the Shifa F1 hybrid tomato variety compared to the Savera F1 hybrid tomato variety in the first plantation period. Subsequently, in the second plantation period, there was a significant difference between the two tomato varieties. Bemisia tabaci showed a preference for the Shifa F1 hybrid over the Savera F1 hybrid tomato variety. These differences occurred during the 1st, 2nd, 4th, 6th, 7th, 8th, and 10th weeks. In the experimental trial for the efficacy of eco-friendly biorational insecticides, spinosad, azadirachtin, Beauveria bassiana and Metarhizium anisopliae, there were significant differences between the treated and untreated plants during the two plantation periods. A high efficacy of spinosad on the B. tabaci population was found. Bemisia tabaci infestation under all the applications was reduced from 50 to 94.61% for the two plantation periods. This obvious decrease in B. tabaci population increase attention to benefits of the different bio-rational insecticides.

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

Modification on the coventional protocol for insect microinjection was performed. This protocol describe a simple and unique protocol for microinjecting Spodoptera frugiperda. Insect eggs with thin chorions such as S. frugiperda or with chorions that are removable can be sensitive to desiccation, resulting in death of the embyro. To control or prevent excessive desiccation, eggs can be covered with liquid during the microinjection process. Spodoptera frugiperda are relatively large insect eggs (about 400μm in diameter) and because the chorion does not have to be removed it is somewhat less sensitive to desiccation during the microinjection process. However, injecting S. frugiperda eggs in the absence of any fluid covering resulted in rapid clogging of injection needles due to rapid drying of residual ooplasm onto the outside of the needle. So, seek for alternative covering liquid became a demand to overcome the lethal effect of the conventional covering liquid in order to developed microinjection and delivering system for the target insect emberyo. New liquids were tested for their compatibility with S. frugiperda viability. Halocarbon oils (either low viscosity #27 or high viscosity #700) which are used routinely during the microinjection of some Diptera, allowed for easy injections but were lethal to S. frugiperda embryos even after removing as much of the residual oil as possible immediately following injection. Alternatively, an emulsion of halocarbon oil and water; polysorbate 20 (Tween 20®); was used and didn’t affect on egg viability (90% hatch rate), while it causes turbidity and made injections more difficult due to the obstructed visibility. Finally, dilution of honey was found to a very effective medium with which to temporarily cover the eggs during injection resulting in a 100% survival rate of properly aged embryos. The solutions viscosity was similar to halocarbon oil #27 and this allowed the honey solution to completely cover the eggs without flowing off of the eggs and onto the glass slide. There were no problems with injection needles clogging due to ooplasm adhering and drying on the outside of the needle, and the honey solution was readily removed immediately after injection. Prolonged (24hrs or longer) exposure of developing embryos to the honey solution was detrimental to embryonic development and led eventually to death of the embryos before hatching and therefore it was removed immediately after eggs were injected.