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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

Antennal sensillae of male and female peach fruit flies, Bactrocera zonata (Saunders) (Diptera: Tephritidae), obtained from three different host fruit species (guava, Psidium guajava L. (Myrtales: Myrtaceae); peach, Prunus persica (L.) Stokes (Rosales: Rosaceae); and orange, Citrus sinensis (L.) Osbeck (Sapindales: Rutaceae)), were studied with scanning electron microscopy. This study was carried out to describe the different types of sensillae present on the three antennal segments (scape, pedicel, and flagellum or funiculus) of both sexes of B. zonata on different host fruit. The antennal segments of females tended to be larger than those of males feeding on peach and guava fruit. On orange, both sexes were similar (no significant differences were found). The first two antennal segments, scape and pedicel, are reinforced by some bristles and have different types of sensillae, including trichoid I, II, S; basiconic II; and sensilla chaetica in different numbers on different host fruit species. Numerous microtrichia, as well as trichoid (I, II), basiconic (I), clavate, and coeloconic (I, II) sensillae were observed on the funiculus with a great variation in number and length. As a result of feeding on different hosts, differences were found between sexes and some plasticity in size, number, distribution, and position of some sensillae, including trichoid, basiconic, chaetica, and clavate on the antennae of the female B. zonata. These sensillae were significantly larger in females. Also, some morphological and morphemetric differences have been found according to their feeding on different host fruit.

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This study was designed to find out the optimum cold storage temperature (4, 7, and 10 °C) and storage period (1–16 weeks) of 3 different immature developmental stages (2, 4, 6 days post parasitism) of the egg parasitoid, Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae) to produce high-quality individuals to be utilized. Also, the effects of cold storage on parasitoids’ fitness in terms of parasitism percentage, developmental period, adults’ emergence percentage, female percentage, and longevity (fed and un-fed) of parents and F1 progeny were investigated. The obtained results revealed that T. bactrae larvae (2-day post parasitism) could be stored for at least 7 weeks at 10 °C, with least changes in their fitness in both the parents and F1 progeny, followed by 7 °C, whereas storage at 4 °C was the fatal temperature in this early stage of parasitoid with a maximum mortality rate that extended to the next generation (F1). Furthermore, female biased sex ratios were observed at all storage temperatures in the parental and F1 generations but with different values. After a cold exposure of pre- and pupal stages (4, 6 days post parasitism) of the parasitoid at 7 °C, adults’ emergence percentage in the parents was low, but the biological performance in progeny was great. In addition, these late stages could be stored for a short period up to 4 weeks at 10 °C with highest performances in both generations, followed by 7 °C. Ten degrees Celsius proved to be the most suitable storage temperature at different parasitoid ages (larvae, pre-pupae, and pupae). Only the larval stage could continue up to 16 weeks of cold storage, and hence, it can be recommended for a short- and/or a long-term storage period.

Background The greater wax moth, Galleria mellonella (L.) (Lepidoptera: Pyralidae), is the major devastating insect pest of beekeeping industry all over the world; however their larvae were valuable to be the most favorable alternative invertebrate model. For this purpose, new-hatched larvae were reared on five different nutritional diets based on: old wax-comb (natural food); wheat flour diet (Triticum aestivum L.); soybean diet (Glycine max); wheat germ diet; and date syrup diet (Phoenix dactylifera L.) till reaching the fully grown 6th instars to evaluate their fitness and hemocytic responses. Results Fully grown larvae from soybean diet had the highest rates of fresh (280 mg) and dry weights (104 mg), water contents (175.6 mg), carbohydrates (1.97%), total hemocyte count (THC) (4746/mm3), total soluble solid (TSS) (21.7%), hemolymph protein concentration (HPC) (1662.5 mg/100 ml), and hemolymph content (density 3.82 mg/µl and volume 70.35 µl/larva), followed by wheat germ diet in comparable to the natural food. All suggested diets considered as rich protein-materials; recording high protein rates on their larvae (39.51–41.87%), with only the exception of old wax-comb had the lowest one (36.63%). Moreover, five types of hemocytes were classified in the larval hemolymph as (prohemocytes (PR), plasmatocytes (PL), granulocytes (GR), oenocytoids (OE) and spherulocytes (SP)), but with different rates related to different diets. Regardless the rearing diets, PR type was the most frequently recorded cell type (73.31%) in hemolymph, followed by PL (8.37%), and the lowest one was OE cells (5.82%). Conclusions The suggested diets of soybean and wheat germ recorded the best results than the other diets used almost, and could be recommended as standard diets to mass-produce healthy and high-quality G. mellonella for in vivo experimentation and/or microbiological studies.

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Background The Egyptian cotton leafworm, Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) is one of the major insect pests, causing a significant damage on different cultivated agricultural crops. Developing an alternative non-chemical tool, an effective and environmentally friendly method to suppress pest's infestation is essentially needed. Therefore, biological control by releasing the egg parasitoids could be the most promising tool for integrated pest management. Results This study was designed to evaluate the efficacy of the egg parasitoid, Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae) as a bio-control agent against S. littoralis egg masses with different physical characteristics (number of egg layer and degree of scale density) in a no-choice and choice tests, under laboratory conditions. Also, the parasitoids’ fitness in terms of parasitism percentage, developmental period, adults’ emergence percentage, female offspring percentage, and longevity were investigated. The results revealed that T. bactrae wasps had a great ability to parasitize S. littoralis egg masses, but with different rates, related to their layers and scales’ thickness in both tests. The highest parasitism percentage was observed on one-layer eggs, followed by two layers. However, 3-layer eggs were the least preferable one. High numbers of adult emergencies (> 80%) were observed in all tested egg masses, except in the case of 3 layers with high scales. Furthermore, female-biased sex ratios were noticed at all examined eggs, with only the exception of high-scaly eggs with a single layer that recorded the lowest rate (≤ 45%). Besides, the survival of adult female parasitoids was not significantly affected in both tests. Conclusions T. bactrae could be used as a bio-control agent against S. littoralis egg masses with different physical characteristics based on the achieved results.