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Abstract 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.

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.