Laboratory experiments were conducted to assess the efficiency of the new strain CCM 8367 of Isaria fumosorosea on different stages of the Egyptian cotton leafworm, Spodoptera littoralis (Boisd.), including soil treatments with pre-pupal and pupal stages. Treatments of larval instars showed a high susceptibility with 3rd, 5th and last instars to suspension of this fungus with concentration 5 × 10⁷ spores/ml. Larval mortality was over 90%. There were no significant differences (P = 0.7929, F = 0.2346) between instar treatments. The commercial fungus, PreFeRal® strain Apopka 97 of I. fumosorosea, which was used in comparison with this new strain caused mortality rates of between 63.33 and 90%. Statistically, differences between the effects of CCM 8367 strain and Apopka 97 were highly significant on the last instar (P = 0.0064, F = 6.479) and extremely significant on the 3rd instar (P < 0.0001, F = 13.29). No significant differences were recorded between the two strains on the 5th instar (P = 0.0597, F = 3.233). Fungal treatments with the late stage insects (end of the last instar or pupal stage) in soil yielded interesting results: the mortality rate on end of final instar larvae was 16.66% when treated with Apopka 97 and 83.33% when treated with CCM 8367. Soil containing pupae of S. littoralis that were inoculated with CCM8367 resulted in a high number of malformed adults, and the mortality rate was 64.52% (32.27% of malformed adults died and 32.25% of pupae fully infected by fungus). Only 3.23% of samples produced morphologically normal adults in this test. The results conclude that the strain of I. fumosorosea CCM 8367 has strong insecticidal effects on S. littoralis and has the potential to be implemented as a novel biocontrol agent.

In laboratory and greenhouse studies, the invading ability, virulence, and mortality caused by Stinernema feltiae and Heterorhabditis bacteriophora were compared. After one and two days of exposure to either nematode species, the mortality of Colordo potato beetle (CPB) Leptinotarsa decemlineata larvae at different instars, third and fourth, was recorded and the number of nematodes invading cadavers was more than the number of nematodes inside the larvae at the late last instar (one day before pre-pupa). Two concentrations, 250 and 500 IJs/dish, infective juvenile nematodes/0.5 ml were tested on different CPB larval instar. S. feltiae was more effective, with fourth instar rather than third and late last instar. On the other hand, H. bacteriophora showed a very weak effect with L. decemlineata. Also it was clear that S. feltiae was more effective and faster than H. bacteriophora: more than 70% of larvae were killed within 24 hours compared with H. bacteriophora which killed 40% of larvae within 48–72 hours. A significant difference in invading efficiency was observed with concentration 2500 IJs/pot in the greenhouse test. The number of adult females found in the cadavers of L. decemlineata larvae was always higher than the number of males. Foliage application of S. feltiae and H. bacteriophora resulted in a significant reduction of the number of damaged leaves and a lower index of damage compared with that in the control. We conclude that S. feltiae has significant potential and can help in the management of the Colorado potato beetle.

The effect of Artemisia monosperma wild plant hexane extract on some biological and physiological aspects of Spodoptera littoralis, as well as some biochemical and histopathological changes after treatment with this extract have been studied. The results indicated that treatment with larvae for two days revealed satisfactory effects in larval mortality (50%) and in larval weight and prolonged the effect in the pupal stage. Also the treatment reduced the food consumption and the amount of faeces of the tested larvae which led to a significant reduction in the final body weight with 76.4%. Treatment also extended the time of food passage through the midgut to 3.2 h compared to 1.38 h in control, and the larvae had a smaller midgut. The enzymatic activity of the digestive enzymes amylase and invertase revealed a significant inhibition in the treated larvae. Also transaminase enzyme activity (AST and ALT) reduced after treatment. The results of phosphatase enzyme activity (ACP and ALP) showed a potent inhibitory effect on both enzymes which more was pronounced in ALP than ACP activity, the percent inhibition being 73.8% and 30.6%, respectively. The histopathological effects of A. monosperma treatment on the midgut of Spodoptera littoralis revealed that the epithelium membrane was exfoliated and completely destroyed. Meanwhile, epithelia cells were strongly vacuolated and considerably elongated. Boundary lines between the cells disappeared.

Nano-formulation of Pelargonium graveolens essential oil was studied to improve its utilization, efficacy, and stability and its effect against (Sitophilus oryzae L.). P. graveolens nanoemulsion was prepared utilizing a high-energy ultra-sonication process and characterized by transmission electron microscopy (TEM). The average of droplets size found 30.99 nm, and the morphology of the droplets formed a spherical shape. Also, a higher zeta potential value of 50.8 mV results in a more stable. Furthermore, the accelerated stability of the optimized nano-formulations provided acceptable results under preparation conditions. There were no significant changes in the physical characteristics of the formulation. The bioassays results indicated that P. graveolens nanoemulsion provided the lower LC50 value 2.298 ppm/cm2, indicating a higher toxicity level, while the free oil value was 67.66 ppm/cm2. S. oryzae mortality increased with increasing exposure intervals and concentration rate when adults were exposed to treated wheat grains. However, increasing the exposure interval increased adult mortality. Progeny emergence six weeks after exposure to this beetle was generally low and after three months decreased with increasing concentration. These findings suggest that P. graveolens nanoemulsion was encourage the use of P. graveolens nanoemulsion in pest control systems for stored products, as well as the development of environmentally friendly materials and long-lasting control agents