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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

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.

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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.