Tossa jute (Corchorus olitorius L.) is an annual vegetable crop belonging to the Tiliaceae family and Corchorus genus. This annual dicotyledonous species originated in Africa and was cultivated to provide bark for fiber fabrication and mucilaginous leaves that are consumed for food as 'Mloukiya' in Arabic countries, where they are consumed either fresh or dried [1]. It is an important green leafy vegetable in many tropical areas, including Egypt, Sudan, India, Bangladesh, and the Caribbean, in tropical Asia such as the Philippines and Malaysia, and in North Africa and the Middle East,

The process of soil salinization and the preponderance of saline water sources all over the world represent one of the most harmful abiotic stress to plant growth. This pointed to the importance of obtaining plants which are tolerant or resistant to salt, considering that projection of climate change for the coming years indicate an increase in temperature and rain scarcity. In the current study, the effect of NaCl was investigated on germinating seeds of Lathyrus sativus L., Vicia sativa L., Vigna radiata L. R.Wilczek and Vigna unguiculata L. Walp., by combining physiological, biochemical, biostatistical and ultrastructural analyses. Our results revealed that germination was not influenced by high NaCl concentrations, while seedling growth was affected even at low NaCl concentrations, probably due to an alteration in water uptake and in organic matter biosynthesis. Nevertheless, the synthesis of antioxidant enzymes, phenolic acids and flavonoids was registered in all species, which tended to cope with the increasing salt stress, allowing a response mechanism such as cytoplasm detoxification and cellular turgor maintenance. Besides, the ultrastructural analysis evidenced plasmolyzed cells close to cells with a normal ultrastructure with no appreciable differences among the species. This research deeply investigates the mechanism of salt‐stress response focusing on species never tested before for their possible tolerance to salinity.

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Carob (Ceratonia siliqua L.) is a tree crop cultivated extensively in the eastern Mediterranean regions but that has become naturalized in other regions as well. The present study focused on the green synthesis of zinc oxide nanoparticles (ZnONPs) from Carob and their evaluation for antimicrobial activity in bacteria and fungi. The synthesized ZnONPs showed strong antibacterial activity against Staphylococcus aureus ATCC 25 923 (92%). The NPs inhibited the growth of pathogenic yeast strains, including Candida albicans ATCC90028, Candida krusei ATCC6258, and Candida neoformans ATCC14116, by 90%, 91%, and 82%, respectively, compared to the control. Fungal inhibition zones with the ZnONPs were 88.67% and 90%, respectively, larger for Aspergillus flavus 15UA005 and Aspergillus fumigatus ATCC204305, compared to control fungal growth. This study provides novel information relevant for plant-based development of new and potentially antimicrobial ZnONPs based on extracts. In particular, the development and application of phytogenic nanoparticles enhances the biocompatibility of nano-scale materials, thereby allowing to tune effects to prevent adverse outcomes in non-target biological systems.

Facing to the harsh environmental constraints, natural populations of widespread plant species may express plastic response, evolve local adaptation or combine both mechanisms in order to maintain their genetic variation and pervasiveness across a wide ecological niche. Here, 79 lines representing height Tunisian populations of Brachypodium hybridum were cultivated in two contrasting phosphorus (P) availability levels and their genetic variation was investigated using forage quality traits to identify the main mechanisms governing their genetic variation. Our results revealed large variation among populations for most traits. PCA analysis showed the separation between coastal and inland populations in both P levels. Importantly, all traits revealed high heritability in both P treatments and the response of most of them to P deficiency was highly influenced by the population effect, which accounted 52.38% of the total variation, indicating strong population differentiation. However, although significant for most traits, only 18.13% of variation was attributed to P treatment, suggesting little plastic response to P deficiency. Importantly, as revealed by the lack of population*treatment effect for most traits, the plastic response was probably common to all populations. Moreover, we found that 56.99% of variation was attributed to environmental factors with distance to coastline, precipitation seasonality, and annual precipitation being the most important factors, suggesting that the strong population differentiation likely reflects local adaptation to specific environmental conditions. Contrary to the coastal populations, which were characterized by high levels of fiber-related traits levels, the inland ones displayed the high values of most energy-related traits, suggesting that these latter were characterized by relatively higher forage quality. Overall, our results suggested that the effect of local adaptation overrides the effect of phenotypic plasticity in explaining the variation of forage quality traits, which indicate a broad adaptive genetic differentiation among the Tunisian populations of B. hybridum in response to P deficiency.

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Nineteen Tunisian onion genotypes were characterized based on phytochemical composition, sugar content, and antioxidant activity. The studied onions showed a great diversity on biochemical contents and composition. It seemed that there were differences between genotype categories (local landraces or local breeding lines) and within the same category. Quercetin and quinic acid were, respectively, the main flavonoid (flavonol) and organic acid (cyclitol) identified and quantified by HPLC. In all studied onions, quercetin was the predominant flavonoid, with the highest content in the local breeding line OP2-w (1142.19 mg 100 g -1 DW). OP3-w showed the highest value of total phenolic as well as total flavonoid content at 12.52 mg GAE g -1 DW and 48.28 RE g -1 DW respectively. Fructose and sucrose were the most abundant sugars in all the genotypes. Clustering and PCA analysis showed a great dispersion of these genotypes which were classified into 3 major groups. The chemical and nutritional composition found highlights the great value of this onion germplasm which can be used for the sustainable conservation and management of Tunisian onion genetic resources.