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The sequence of the DNA contains coding and non-coding regions. The role of the non-coding regions is not known and is hypothesized to maintain the structure of the DNA. This study aimed to investigate the structure of the non-coding sequences in honey bees utilizing bioinformatics. The non-coding sequences of the mtDNA of three honey bee species Apis dorosata, Apis florea, Apis cerana, and ten subspecies of Apis mellifera were investigated. Different techniques were utilized to explore the non-coding regions of these bees including sequence analysis, phylogenetic relationships, enzymatic digestion, and statistical tests. Variations in size and sequences of nucleotides were detected in the studied species and subspecies, but with the same nucleotide abundance (i.e. nucleotides A were more than T and nucleotides G were less than C). The phylogenetic tree based on the non-coding regions was partially similar to the known phylogenetic relationships between these bees. The enzymatic digestion using four restriction enzymes confirmed the results of the phylogenetic relationships. The statistical analysis based on numerical codes for nucleotides showed the absence of significant variations between the studied bees in their sequences in a similar way to results of neutrality tests. This study suggests that the non-coding regions have the same functional role in all the studied bees regardless of the number of nucleotides, and not just to maintain the structure of the DNA. This is approximately the first study to shade lights on the non-coding regions of the mtDNA of honey bees.

Panonychus citri (citrus red mite) is a devastating pest of citrus orchards. The conventional chemical acaricides have been strongly forbidden for the management of agricultural insect pests in China. Therefore, we evaluated the susceptibility of adult and nymphs P. citri in laboratory against eight isolates of four fungal species, Akanthomyces lecanii, Metarhizium anisopliae, Beauveria bassiana and Aschersonia aleyrodis. Each citrus seedling having 40 adults (2-d-old) and nymphs (on separate plants) were sprayed with isolates at the concentration of 104 ~ 108 conidia mLˉ1 whereas controlled seedlings were sprayed with 0.02% Tween-80. After 9 days of fungal exposure, the four fungal isolates caused more than 50% mortality of mites, such as; 85.6%, 87.9%, 64.6% and 79.7% by A. lecanii (V3450), B. bassiana (BFZ0409), M. anisopliae (MFZ0706) and A. aleyrodis (AsG0910), respectively. The nymphal mites were less susceptible to applied fungi compared to adults. The LC50s of the tested isolates were determined by the fitted time-concentration-mortality relationships, which declined over days after spray. LT50s were decreased with a high concentration of isolates. After the 9-d inoculation, two isolates of B. bassiana (BFZ0409 and D1344) and one isolate of A. lecanii (V3450) were highly effective at the minimal dose of LC50 of 104 conidia mLˉ1 and are promising candidates to control mites, as compared to other tested fungal isolates.

American bolloworm, Helicoverpa armigera Hubner (Noctuidae: Lepidoptera) is considered as a major pest of various crops all over the world. It is mainly controlled by indiscriminate use of synthetic insecticides in the world due to which this pest developed resistance to most of the available insecticides. Therefore, in the current study, the efficacy of virulent strain of HaNPV (0.5 × 109 PIB/ml) alone and in combination with recommended doses of spintoram (20 g/100 L of water) and emamectin benzoate (200 ml/100 L of water) was tested in field. The combination of HaNPV with spintoram and emamectin benzoate 100% reduced the larval population as compared to emamectin benzoate and HaNPV alone. This suggested that the combination of spintoram and emamectin benzoate with HaNPV could be used in field to manage the infestation of H. armigera.

Background Mass rearing cost of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) is one of the critical methods for the successful utilization of Baculovirus pathogenicity and sterile insect technique (SIT). Effectiveness of both SIT and S. littoralis Nucleopolyhedrosis Virus (SpliNPV) was assessed in response to plant-based diet and substitution of agar with commercial sources of gelling components as feed. Results Pupal and adult recoveries produced by castor bean leaves were significantly high, followed by the agar-based diet. Moreover, larval durations were significantly prolonged for (starch + gelatin)-based diet than the other dietary diets. Obviously, SpliNPV pathogenicity against the larvae reared on (starch + gelatin)-based diet was 2.5 and 2 times higher than those reared on castor leaves and agar-based diet, respectively. Contrary to expectation, the sterility doses of male moths produced by castor leaves and agar-based diet were relatively similar. Conclusion The findings suggest that the lowest cost diets (starch + gelatin)-based diet could be used effectively for increasing the SpliNPV pathogenicity, while either castor leaves or agar-based diet could be considered as a promising choice for SIT program.

American bolloworm, Helicoverpa armigera Hubner (Noctuidae: Lepidoptera) is considered as a major pest of various crops all over the world. It is mainly controlled by indiscriminate use of synthetic insecticides in the world due to which this pest developed resistance to most of the available insecticides. Therefore, in the current study, the efficacy of virulent strain of HaNPV (0.5 × 109 PIB/ml) alone and in combination with recommended doses of spintoram (20 g/100 L of water) and emamectin benzoate (200 ml/100 L of water) was tested in field. The combination of HaNPV with spintoram and emamectin benzoate 100% reduced the larval population as compared to emamectin benzoate and HaNPV alone. This suggested that the combination of spintoram and emamectin benzoate with HaNPV could be used in field to manage the infestation of H. armigera.

Objectives: Ensuring adequate treatments for acaricide efficacy to combat mite infestation is a pre-requisite for healthy honeybees and a good yield of hive products. Therefore, this study aimed to assess the effect of the mode of application on efficiency of two acaricides; Vapcozin-20 (amitraz) and Mavrik 2F (fluvalinate) against Varroa mite infesting brood and adult honeybees. Methods: To do so, we used 21 honeybee colonies (3 colony per treatment) between December 2018 and March 2019. Varroacides were applied by three different methods: cotton strips (impregnated in each tested acaricide solution for 24 h) or direct spraying (5 mL for each colony) or using carton paper (impregnated in each tested acaricide solution for 5 min) then put directly on the top of brood combs. All treatments were applied twice at a month interval. We also quantified acaricides residues in honey and beeswax after 1, 15, 30, 60 and 90 days of acaricides treatment. Results: The different application methods of both acaricides against V. destructor showed relatively similar efficiencies in both brood and adult honeybees that ranged from 93.8 to 100% for Mavrik 2F and from 83.75 to 96.37% for Vapcozin with no significant differences between different application methods. Fluvalinate residues detected in both honey and wax collected from colonies treated with the strips method, exceeded the maximum residue limits (0.05 ppm for both honey and wax) according to EU Pesticides database. While amitraz residues were not detected in any colonies treated with Vapcozin-20 after 3 months of treatment, regardless of the application method. Conclusions: The three different methods of application of Mavrik 2F and Vapcozin-20 showed great efficiency for the control of Varroa mite, however the application of both miticides using carton paper method was the most appropriate because it showed very minimal acaricides residues.

Objectives The small hive beetles (SHBs) cause dangerous damages to bee colonies in several countries. Some African countries represent the native land to these beetles. The SHBs are not well established in North Africa and South Europe (the closest land to the native countries). Therefore, this study aimed to model the current and future distribution of SHBs in Africa and South Europe utilizing temperature datasets. Methods A total of 250 occurrence data was incorporated in the study. Six temperature variables were used in the Maxent analysis to model the suitability of the study countries for the SHBs. Three climate models were used to estimate the future distribution of SHBs in 2050 and 2070, considering the lowest and the highest limits of the Shared Socio-economic Pathways (126 and 585). Results and conclusions The high performance of the used model was confirmed by analyzing omission/commission rates as well as the area under curve. All future maps showed the potential expansion of SHBs towards the Northern parts of Africa and some parts in Europe. Such potential expansion was discussed in light of current distribution of SHBs. The study concluded that the SHBs can cause damages to bee colonies in new regions in Africa and Europe during the near future.

The landfill garbage includes organic and inorganic matter. The organic matter covers more than 50% of the total waste material. Due to improper management of landfill garbage, it causes serious risks to human health directly by the emission of toxic gasses. On the other hand, landfill sites are the natural habitat of several microbes and arthropods. The present discussion illustrates the impact of landfill garbage on insect ecology and human health. Here, we highlighted the arthropod density as well as diversity. Moreover, the population of insect vectors of various diseases, insect scavengers as well as pollinators has been pinpointed. It shows that landfill sites and adjacent areas are hotspots for a wide variety of arthropods. The proper management of landfill sites could reduce the population dynamics of various insect pests, and health risks could be decreased in low-and middle-income countries.