Mustafa M. Soliman

Previous research has shown that the effects of different drugs on the growth rate of blow flies vary by species, which can influence the determination of the minimum post-mortem interval (PMImin​). In this study, we assessed how morphine affects the development, growth, and survival rate of Chrysomya megacephala (Fabricius, 1794), a forensically important blow fly species, and whether these effects are dose dependent. We also measured morphine concentrations in insect samples (3rd -instar larvae and puparial cases) and in various post-mortem tissues of rabbits (cardiac blood, skeletal muscle, and liver). Rabbits were administered two lethal doses of morphine hydrochloride (5 and 10 mg/kg), then sacrificed, and tissue samples were collected for toxicological analysis. At a controlled temperature of 37 °C, newly hatched larvae (1–2 h old) were placed on the rabbit carcasses and randomly sampled at 12 h regular interval (12–132 h) to determine larval development time, puparial development time, larval mortality, larval length, and larval weight. Changes in these insect parameters led to an underestimation of PMImin by up to 15.92 h if the presence of morphine was not considered. Moreover, morphine concentrations in all insect samples (180 and 223 ng/g in the 3rd instar larvae; 40 and 45 ng/g in the puparial cases after treatment with 5 and 10 mg/kg of morphine hydrochloride, respectively) and rabbit tissues (1129 and 2564 ng/g in the cardiac blood; 1777 and 2823 ng/g in the liver; 825 and 1070 ng/g in the skeletal muscles after treatment with 5 and 10 mg/kg of morphine hydrochloride, respectively) were measured using high-performance liquid chromatography system equipped with a binary pump and UV detector. Morphine can affect the development of different life cycle stages of Ch. megacephala, highlighting the importance of accounting for its presence when determining PMImin ​ in such conditions. The data obtained could aid in criminal investigations. Although a concentration-dependent effect has been discussed, the use of whole animal carcasses may lead to uneven distribution of the drug, and concentrations in the areas from which larvae are feeding may differ significantly due to ante-mortem processes in the body.

The peach fruit fly (Bactrocera zonata), a significant polyphagous pest, poses a considerable threat to fruit crops across its expanding range. Although climate change significantly impacts pest populations, its effects on B. zonata remain understudied. This research examined B. zonata population dynamics across two distinct Egyptian ecological zones (Sohag and Ismailia Governorates) from 2013–2023 using pheromone traps and climate data. Results revealed significant spatial and temporal variations in abundance patterns. Both regions displayed a unimodal distribution, with Sohag exhibiting a distinct peak during September to November, whereas Ismailia showed a broader peak period spanning from August to December. Temperature significantly influenced population levels while precipitation showed no significant effect. Similarly, our results indicated increasing population trends in both regions despite no significant long-term temperature changes. These findings suggest that factors beyond temperature alone, such as host fruit availability, regional environmental variations, and potentially evolving agricultural practices, drive B. zonata population growth, highlighting the need for comprehensive, climate-responsive pest management strategies that account for regional variations.

{Pollutants in an environment can have long-term implications for the species living there, resulting in local adaptations with implications for their genetic structure. Heavy metal pollutants infiltrate soils and groundwater, bioaccumulate in food webs, and negatively impact biota. In this study, we investigated the degree to which the genetic structure and variability of the slender green-winged grasshopper (Aiolopus thalassinus (Fabricius) (Orthoptera: Acrididae)) were impacted by heavy metal pollution and distance. We used the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) method to examine the genetic variability of populations in 3 heavy metal-polluted and 3 unpolluted locations across varying geographical distances in Egypt. The heavy metal concentrations of cadmium, copper, lead, and zinc were measured from the grasshopper tissue and soils. Sixty-nine unique and polymorphic bands were produced by 4 primers. Cluster and principal component analyses separated the populations inside and outside Cairo into 2 main branches, which were further divided into smaller branches corresponding to their geographical regions. We found no differences in the Shannon genetic diversity index between populations or with increasing heavy metal concentrations in either the soil or the grasshopper tissue. Our results showed a greater genetic variation among populations than between populations within the same location, indicating populations within locations were less differentiated than those between locations. The moderate correlation between genetic similarity and spatial distance suggests geographical isolation influenced grasshopper population differentiation. Based on the RAPD analysis, environmental pollutants and geographical distances impact the A. thalassinus population structure, potentially restricting gene flow between sites even at small spatial scales.}