Our research shed light on the perspective of formulation technology regarding its responsibility to provide phyto-insecticides that are worthy of research into potential novel applications. There has been an increase in interest in using nanoemulsion as a new formulation in a variety of sectors during the last several decades. Boswellia sacra essential oil (Fam: Burseraceae) from the resin of frankincense trees has been recently proposed as a promising ingredient in a new generation of botanical insecticides. Frankincense nanoemulsion was formulated in 5% ratios comprising frankincense oil, surfactants, and water. A frankincense nanoemulsion was prepared using a high-energy ultra-sonication process and characterized by dynamic light scattering transmission electron microscopy surface tension, viscosity, and zeta potential value. Gas chromatography/mass spectrometry (GC/MS) was used to identify the chemical profiles of frankincense essential oil. Furthermore, insecticidal effects against second instar larvae of the spiny bollworm, Earias insulana, as well as their latent effects on the larvae were studied. In the present study, the formulation was a good nanoemulsion. The surface tension was 53.69, the viscosity was 4.76 cPs, the zeta potential was-10 mV, and the size distribution was 41.30 nm. The polydispersity index (PDI) of the nanoemulsion was found to be 0.26, and the morphology of the frankincense nanoemulsion was visualized in a spherical shape. The main constituents identified in frankincense oil were α-pinene (15.52%); monolinolenin (12.92%); and geranylgeranyl acetate (9.99%). The results showed significant insecticidal activity against the larval stage and considerably decreased the pupation percentage with increasing the volume of the frankincense nanoemulsion. On the other hand, the latent effects of the frankincense nanoemulsion on E. insulana resulted in a higher prolongation of larval and pupal durations as well as a significant reduction in the weight of larvae and pupae of E. insulana. Additionally, frankincense nanoemulsion dramatically influenced the adult emergence percentage. It also caused a significantly lower hatchability percentage compared to the untreated control. The concentrations used and the types of mating combination have a significant effect on the fecundity of E. insulana. This novel frankincense nanoemulsion formulation could be used in strategies to control the spiny bollworm on cotton plants.

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Toxicity and sublethal effects of emamectin benzoate, novaluron and diflubenzuron were evaluated against the 2 nd instar larvae of cotton leafworm (CLW). The joint toxic action of emamectin benzoate with novaluron or diflubenzuron was carried out. Emamectin benzoate (LC 50 = 0.014 mg L-1) was 264.3 and 5707.1 times more toxic than novaluron (LC 50 = 3.7 mg L-1) and diflubenzuron (LC 50 = 79.9 mg L-1), respectively. Novaluron was approximately 21.6 times more toxic than diflubenzuron. After 24 hrs of exposure, all mixtures of emamectin benzoate (at LC 10 or LC 25) with novaluron or diflubenzuron (at LC 10 or LC 25) resulted in antagonistic effects with co-toxicity factors (CTFs) ranged between-25 to-700 except the mixture of emamectin benzoate at LC 10 with novaluron at LC 10 (CTF = 60). Mixtures of emamectin benzoate at LC 10 with novaluron at LC 10 and emamectin benzoate at LC 25 with novaluron at LC 25 resulted in potentiating effects after 48, 72 and 96 hrs of exposure. On the other hand, all mixtures of emamectin benzoate with diflubenzuron resulted in antagonistic effects. Emamectin benzoate, novaluron and diflubenzuron at the two sublethal concentrations reduced average larval weight, average time to the pupation, %pupation, pupal mean weight and %adult emergence compared to control. Results of this study verified the lethal and sublethal effects of emamectin benzoate, novaluron and diflubenzuron on the larval stage of S. littoralis, which negatively affect some biological parameters and insect population can be negatively affected. Emamectin benzoate, novaluron and diflubenzuron can be used for S. littoralis control and in resistance management programs, because their mode of action is different from pyrethroid, carbamate and organophosphate insecticides.

Field studies were conducted during 2015 and 2016 cotton growing seasons, at AbouElmatameer, El-Behira Governorate to evaluate certain insecticide sequences in controlling two cotton bollworms pink bollworm (PBW), Pectinophora gossypiella, (Saund) and spiny bollworm (SPW), Earias insulana, (Boisd.) The side effects of all insecticide sequences on the lady beetle, Coccinella undecimpunctata was also determined. During 2015 season, sequence 2 (Dursban ® , Rado-X ® , Radiant ® , Cothrin ®) and sequence 6 (Dursban ® , Rado-X ® , Radiant ® , Proclaim ®) achieved the highest efficacy against PBW, gave general mean reduction percentages 81.4 and 83.5%, respectively. In season 2016, sequence 6 revealed the highest efficacy where the general mean reduction percentage was 83.3%. Sequences 6 induced the highest reduction percentages in cotton bolls infested by SBW in 2015 and 2016 seasons, with general mean reduction percentages 84.0 and 82.3%, respectively. Sequence 4 (Cothrin ® , Radiant ® , Rado-X ® , Dursban ®) achieved the least efficacy against PBW and SBW in both seasons 2015 and 2016. Sequence 6 proved to be the least toxic on C. undecimpunctata. On the other hand, all other sequences were comparable in there effects on C. undecimpunctata in both seasons.

The comparative toxicity of two Emamectin benzoate [(Speedo5.7% WG) and (Basha 1.9% EC)], two Lambdacyhalothrin [(Bestend 10% WP) and (Max sped 5% EC)] were examined against the cotton leafworm Spodoptera littoralis (Boisd.) 4 th larval stage on castor bean leaves. The effect of rate spreading droplets on the toxicity of Emamectin benzoate and Lambdacyhalothrin formulations were investigated under laboratory conditions. The results showed that Lambdacyhalothrin (Max sped 5%Ec) exhibited the highest toxicity against the fourth larval stage of S. littoralis with LC 50 values of 0.007 ppm. In contrast, Lambdacyhalothrin,(Bestend 10% WP) had the lowest toxicity with LC 50 values of 0.033 ppm. On the other hand, the Emamectin benzoate (Speedo5.7% WG) was given the lowest LC 50 value of 0.0061 ppm followed by (Basha 1.9% EC) LC 50 value of 0.0097 ppm. The results of joint toxic effect between rate spreading droplets and insecticides indicated that Emulsifiable concentrate of Lambdacyhalothrin and Emamectin benzoate formulation was the highest both rate spreading droplets and the mortality rates