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This research can be considered as the first complete survey for the valorization of new olive genotypes cultivated in the South-East of Tunisia as well as their oils. The study aimed to characterize the phytochemical composition of virgin olive oil produced from two olive cultivars, namely Nourgou and Gousalani. The pomological characterization of fruits, the quality criteria and the phytochemical profile were quantified. Additionally, antioxidant activity was evaluated using Ferric reducing antioxidant power (FRAP) and Oxygen radical absorbance capacity (ORAC) tests to also obtain a bioactive characterization of these monovarietal olive oils. The obtained results revealed that the analyzed olive oils samples can be classified into Extra Virgin category (EVOO) according to the regulated physicochemical characteristics. Our findings showed a significant variability in the chemical parameters of the analyzed EVOO likely associated with the genetic potential, mainly for chlorophylls contents (1.37–1.64 mg/kg), in carotenoids pigments (3.97–10.86 mg/kg), in α-tocopherol (175.59–186.87 mg/kg), in sterols (1036.4–1931.4 mg/kg) in oleic acid (65.33–68.73%), in palmitic acid (C16:0) (13.32–17.48%), in linoleic acid (C18:2) (11.06–13.47%). Additionally, the HPLC-MS/MS analysis showed that the two EVOOs analyzed contained appreciable amounts of total polyphenols, ranging from 348.03 up to 516.16 mg/kg, in Nourgou and Gousalani oils, respectively. Regarding the individual phenolic compounds, the EVOO samples were mainly characterized by phenolic alcohols, phenolic acids, secoiridoids, verbascoside, flavonoids and phenolic aldehydes. The prevalent simple phenolics detected were secoiridoids with the dominance of the oleuropein aglycone in Gousalani oil. In addition, findings from in vitro antioxidant assays (FRAP and ORAC) revealed that the two studied oils possessed a powerful antiradical activity and a good reducing power capacity. In conclusion, these new EVOOs exhibited a superior quality compared to other Tunisian varieties, considering their antiradical activity and reducing power capacity. [ABSTRACT FROM AUTHOR]

Pearl millet (Pennisetum glaucum (L.) R. Br., 2n = 2x = 14, Poaceae), is a cross-pollinated, warm-season crop grown worldwide. To select genotypes for breeding pearl millet cultivars that adapt to drought condition in southern Tunisia, we evaluated the grain yield (GY) and yield-related traits using a set of 27 landraces at two locations in southern Tunisia for two grown seasons (2019 and 2020). The genetic variability, phenotypic and genotypic association, and path coefficient (PC), based on grain yield (GY) and different yield-related agronomic traits, were evaluated. Analysis of variance and BLUPs value revealed a wide range of variability and the possibility of genetic selection for traits that are advantageous. Broad sense heritability (H) for all the traits ranged from 24.10% for grain yield (GY) to 57.11% for spike length (SL), indicating low to moderate inheritability. Genetic advance as a percentage of the mean (GAM) ranged from high (29.56%) for principal panicle weight (PPW) to moderate for all the traits except from plant high (PH) (7.31%). For all the traits, the phenotypic coefficient of variation (PCV) was higher than genotypic coefficient of variation (GCV), indicating the magnitude of environmental conditions. GY was significantly correlated with all the traits at the genotypic and phenotypic level. According to the path coefficient, the traits PPW and SL displayed the highest direct effects on GY. Heatmap analysis demonstrated a clear segregation between the early and late genotypes based on their geographic origin. Based on the cluster analysis and FAI-BLUPS analysis, genotypes G11, G13, G12, G17 and G18 were selected as the best-performing genotypes with the shortest cycle. [ABSTRACT FROM AUTHOR]

Soil salinity is one of the most brutal environmental factors that affect crop growth and productivity. Chenopodium quinoa is known as one of the essential food crops in the future due to its agronomic and nutritive value and its strong adaptability to stress environments and soil conditions. However, the molecular aspects of salt tolerance of quinoa remain not well known. Therefore, the expression study of candidate genes related to salt tolerance has become one of the most important features for the identification of their functions. However, one of the most crucial points in Quantitative PCR (qPCR) data analysis is the selection of appropriate reference gene that should be stable and unaffected in a given condition. In this study, six candidate reference genes were analysed in order to select the most stable one under salt stress conditions. The expression stability was assessed using three different algorithms: geNorm, NormFinder and BestKeeper. The most stable and appropriate reference genes screened in this study whose expression was confirmed to be constant in different salt treated and untreated quinoa plant were Monensin sensitivity1 (MON1) and Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and Factor elongation 1-alpha (EF-1α), while Ubiquitin-conjugating enzyme (UBC) and Ubiquitin-protein ligase 7 (UPL7) had the worst stability. However, the data obtained by BestKeeper demonstrated slight differences compared to those from geNorm and NormFinder. Overall, we designated MON1 and GAPDH as the best candidates and the most stable housekeeping gene under salt stress conditions and their geometric means would provide accurate normalization factor for expression data in Chenopodium quinoa. [ABSTRACT FROM AUTHOR]