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The aim of this research was to explore the chemical composition and evaluate the insecticidal activities of Ruta graveolens, Mentha pulegium and Ocimum basilicum leaves essential oils from south of Tunisia. Fumigant toxicities were assessed toward the most important and destructive insects attacking dates in storage in Tunisia namely Ectomyelois ceratoniae and Ephestia kuehniella. GC–MS analyses showed that major compounds of O. basilicum essential oil were linalool (29.23%), methyl cinnamate (18.97%) and eugenol (5.84%), followed by 1,8-cineole (5.74%), α-cadinol (5.69%), estragol (4.72%) and α-bergamotene (4.24%), whereas M. pulegium essential oil had 1,8-cineole (14.60%), p-menthan-3-one (14.9%), piperitenone (11.4%), carene (10.19%), menthol (8.76%), trans-caryophyllene (6.64%) and menthyl alcohol (6.14%) as major components. The essential oil extracted from R. graveolens was remarkably rich in hydrocarbon ketones (52.5%) mainly 1-nonene (19.4%), 2-undecanone (16.22%) and 2-nonanone (11.9%). Results demonstrated that fumigant toxicity varied with insect species, essential oil concentration and exposure time. Lethal concentration (LC50) values of O. basilicum, M. pulegium and R. graveolens were, respectively, 0.96, 0.3 and 1.02 μL/L air on E. kuehniella and were 1.23, 0.31 and 1.97 μL/L air on E. ceratoniae. M. pulegium essential oil was more toxic to the two stored date pests E. kuehniella and E. ceratoniae at all tested concentrations. [ABSTRACT FROM AUTHOR]

The article focuses on a research conducted in order to compare the life cycle, longevity and fecundity of the spider mite Oligonychus afrasiaticus, on fruits of four date palms in southwestern Tunisia. It discusses the variation of duration of the whole immature phase from egg to adult emergence between host plants. The study revealed the substantial effects of the host plant on intrinsic rate of natural increase, net reproductive rate, and survival of the adult stage of O. afrasiaticus

Management of the COVID-19 pandemic relies on molecular diagnostic methods supported by serological tools. Herein, we developed S-RBD- and N- based ELISA assays useful for infection rate surveillance as well as the follow-up of acquired protective immunity against SARS-CoV-2. ELISA assays were optimized using COVID-19 Tunisian patients' sera and prepandemic controls. Assays were further validated in 3 African countries with variable endemic settings. The receiver operating curve was used to evaluate the assay performances. The N- and S-RBD-based ELISA assays performances, in Tunisia, were very high (AUC: 0.966 and 0.98, respectively, p < 0.0001). Cross-validation analysis showed similar performances in different settings. Cross-reactivity, with malaria infection, against viral antigens, was noticed. In head-to-head comparisons with different commercial assays, the developed assays showed high agreement. This study demonstrates, the added value of the developed serological assays in low-income countries, particularly in ethnically diverse populations with variable exposure to local endemic infectious diseases., (Copyright © 2023 Elsevier Inc. All rights reserved.)