The present study is the first attempt in Egypt which focused on determining the development rate of Spodoptera frugiperda at different constant temperatures, the number of degree-days (DD's) required for each stage to complete development, as well as the degree-days required for overall egg-to-adult development. The study was conducted under three constant temperatures (20, 25
This study was conducted to evaluate the efficacy of the bio-insecticide Bacillus thuringiensis (Dipel 2x ® 6.4 % WP) against, 1 st and 2 nd instar Larvae of Sesamia cretica compared with methomyl (Lannate 90 % SP). After 48 hours from treatment, The LC 50 value of B. thuringiensis for 1 st instar and 2 nd larvae were 0.00526 and 0.7 gm, respectively. While the LC 50 of methomyl after 24h. for 1 st instar and 2 nd larvae were 3394 and 5481 ppm, respectively. After treatment of 1 st and 2 nd instars larvae of S. cretica with LC 50 concentrates of B. thuringiensis, the average larval duration of S. cretica were (36.53 & 24.69) and (33.78& 20.31) days for treated and untreated, respectively. In addition, the pupation percentage was (47 & 92 %) and (18 & 84 %) for treated and untreated, respectively. The larval mortality percentage was (53 & 8 %) and (82 & 16 %) for treated and untreated, respectively. The pupal weight for (treated & untreated), S. cretica were (0.1887 & 0.184 gm) and (0.1842 & 0.1601 gm) when it treated as 1 st and 2 nd instars larvae, respectively. Furthermore, the pupal duration were (12.14 & 10) and (10.44 & 9.83 days) for (treated & untreated), when S. cretica treated as 1 st and 2 nd instar larvae, respectively. The total adult emergence for 1 st instar and 2 nd instar larvae were (94 & 100%) and (100 & 100%) for treated and untreated, respectively. On the other hand results indicated that, after treatment of 1 st and 2 nd instar larvae of S. cretica with LC 50 concentrates of methomyl, the average larval duration of S. cretica were (31.41 & 24.69) and (33.87& 20.31) days for treated and control, respectively. The pupation percentage was (34 & 92 %) and (28& 84 %) for treated and untreated when S. cretica treated as 1 st and 2 nd instars larvae, respectively. The larval mortality percentages were (66 & 8 %) and (72 & 16 %) for treated & untreated, respectively. The pupal weight for treated and control, were (0.1626 & 0.184 gm) and (0.1994 & 0.1601 gm), respectively. The pupal duration were (12.41 & 10) and (10.83 & 9.83) days for treated and untreated, respectively. The total emergence percentage for 1 st instar larvae were (100 & 100 %) and (85.7& 100%) for 2 nd instar larvae for each (treated & untreated), respectively.
Malnutrition is a main threat to honey bees. Health and the inability to resist adverse conditions are the main losses resulting from nutritional deficiencies. To address this problem, substitute diets are provided to honey bee colonies at dearth times. The present study was conducted to examine the vital impacts of 2 new substitutes on caged honey bee workers. The main components of both diets (A and B) were sugar, powdered milk, and brewer's yeast fortified with chamomile extract. Diet A was distinguished with chickpeas and corn. Diet B was distinguished with soybeans and wheat germ. Palatability of both diets has been reported in this study with more tendencies towards soybeans and wheat germ components. In comparison with control workers fed on sugar syrup only (1:1), workers fed on diets A and B have shown higher significant survival rates, in addition to outstanding findings of thoraces weights and mandibular and hypopharyngeal glands development. Accordingly, palatability and nutritional diversity in diet proteinaceous sources should be considered in provided substitutes. Diets A and B are highly recommended to be applied in apiaries.
Being the most invasive and destructive pests in maize fields, the promising insect; is the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). The first onset of fall armyworm in Egypt started in 2019 in the south of Egypt among maize plants in Aswan Governorate. Heading north, the pest spread quickly to Luxor, Qena, Sohag and Assuit governorates in the south. Many synthetic insecticides were recommended to control this insect pest. For this purpose, this research was to evaluate the potential effectiveness and toxicity of the following insecticides, Methomyl (Lannate ® 90%), Chlorpyrifos (Dofos 48%) and Spinosad (Tracer 24%) on the biological aspects of S. frugiperda in the laboratory. Bioassays were conducted on the newly molted 4 th instar of S. frugiperda larvae under 25 ± 2 °C room temperature, 70 ± 10% relative humidity. The LC50 values were 105.5, 470, and 2.5 ppm for the compounds methomyl, chlorphyrifos, and spinosad, respectively. Distilled water was served to the control group. Accumulative larval mortality percentages were 42, 55 and 44 for methomyl, chlorpyrifos, and spinosad, respectively. A significant increase in the total duration of the consecutive larval instars and pupae was recorded post-treatment at the 4 th instar larvae with the LC50 concentrations of tested insecticides. Accordingly, the differences were significant in the toxicity to S. frugiperda; hence, the variation in LC50 is a reference to the varying actions of the tested insecticides. These data indicate that these recommended synthetic insecticides are effective in controlling fall armyworm instars.
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