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Using saline water, especially in arid and semi-arid areas is unavoidable in order to overcome increasing water demand and drought. Salinity is a widespread stress limiting the growth and productivity of cultivated plants. In this frame the identification and selection of genotypes able to produce under salt stress conditions is necessary for the success of the cultivation in marginal areas of the Mediterranean basin. Activities during the two years took into account the evaluation for salt tolerance of 40 accessions of Crocus sativus L. and 14 of Crocus spp.. Corms were provided by the Bank of Plant Germplasm of Cuenca -Spain- (BGV CU). The plants were grown in flowerpots with peat and volcanic sand (1:1 in volume), as substrate. Corms were sown with a density of 166 n. m-2 (21 corms per pot). Salinity levels were 820, 4070 and 6420 µS cm-1, produced by 0, 1.5 and 3.0 g l-1 NaCl, respectively. Flowering and cormlets growth parameters were evaluated during both growing seasons. Number of produced flowers was strongly decreased, in all accessions, with increase in salinity level, especially during the second year, where only a few accessions produced some flowers. BCU 1672, 1640 and 1782 (obtained from Teruel, Albacete and Cagliari, respectively) were more tolerant accessions of Crocus sativus in the first year. Among the wild crocus, C laevigatus (BCU 1835) was the most tolerant to salt stress with 0.5 flower per plant at the highest levels of salinity (6420 µS cm-1). On average of all accessions subjected to salt stress, 1.95, 1.0 and 0.54 flowers per plant were obtained at salinity levels of 820, 4070 and 6420 µS cm-1, respectively. With reference to Crocus s. the average weight of the corms at the beginning of the test was equal to 13 g with a reduction at the end of the two-year period of 58 percent, while for the Crocus spp. with an initial weight of 1.5 g, a reduction of 68 percent was recorded at the end of the second year cycle

Plant diversity refers to the variety and variability of plant species. The vegetation cover of a given area has a definite structure and composition. Ethiopia is one of the states in the world with high level of biodiversity. Environmental degradation in Ethiopia is becoming the overriding cause for the loss of biodiversity. There is a significant lack of information on the ecology and diversity of some of the vegetation types in the country.

Essential oils (EO) are liquid mixtures of volatile compounds obtained from aromatic plants. They constitute what is called the "essence" of a plant and usually have pleasantly scented fragrances[1]. The chemical composition of the EO extracted from Lemon verbena [Aioysia triphylla (L'Her) Britton], has been frequently studied because the aerial parts of this plant are used in folk medicine. Lemon verbena is an herbal species indigenous to South America which was introduced into Europe at 17th century[2]. it has been cultivated mainly due to the lemon-like aroma and utilized for herbal tea, which is reputed to have antispasmodic, antipyretic, sedative and digestive properties[3). The aim of this study was to determine the accumulation of EO in Lemon verbena growth under different fertilizer regimes of nitrogen (N), phosphorus (P), potassium (K) and boron (B). All the nutrients were applied as liquid organic fertilizers. The nutrient solution was applied in soil surface through the holes made in the anti-weeds plastic mulch by where the plants grow. The nutrients were applied at the rates: 0, 37.5, 75 and 112.5 kg N ha·•; 0, 37.5 and 75 kg P P s ha·1; 0, 37.5 and 75 kg ~0 ha·1; and 0. 75 and 1.5 kg B ha·•. The total rates of fertilizers were fractionated into three applications during the growing season. The experimental design included three replications of all fertilizer treatments. Field samples, 5 to 6 individual plants were collected, weighed and dried. The determination of the EO yield was performed by the hydro-distilled process. The plant material was subjected to extraction for 3 h using a Clevenger-type apparatus. The results here presented should be considered preliminary. However, it seems that the increase in biomass due to the increasing rates of N, P and B decreased the oil content in the plant. ForK treatment, that relationship was not found. The high oil yields were found from the samples coming from the most productive plots. Funded by Projects PRODER no 46025 - Gestao Sustentave/ da Produr;ao de Plantas Aromaticas e Medicinais, and PRODER n° 46207 - Adaptar;ao cultural de hortela-vulgar e Stevia. info:eu-repo/semantics/publishedVersion

Considering the association of plants consumption and utilization with the treatment of some illnesses and diseases, several aromatic and medicinal plants have been used in traditional and contemporary medicine. This capacity has been proven scientifically and there are numerous studies describing their therapeutic properties in the treatment of inflammatory and cardiovascular disorders, diabetes, among other conditions [1] . The antioxidant and antimicrobial activities have already been studied in a wide variety of plants, which have been shown to contain bioactive molecules effective against pathogenic microorganisms and capable of removing reactive oxygen species formed in cells [2,3]. In this sense, ten aromatic and medicinal plants ( Eucalyptus globulus Labill., Olea europaea L., Melissa officinalis L., Origanum vulgare L., Glycyrrhiza glabra L., Arbutus unedo L., Matricaria recutita L., Thymus vulgaris L., Ocimum vulgare L., and Salvia officinalis L.) were selected to perform an initial screening for the exploration of natural ingredients with bioactive potential. The plant extracts were obtained after ethanolic extraction. The antioxidant activity was evaluated through two in vitro cell-based assays, namely the lipid peroxidation inhibition test (TBARS) and the oxidative hemolysis inhibition test (OxHLIA), and antimicrobial activity was tested by the broth microdilution method, against a panel of bacteria and fungi, selected according to their public health importance. These analyses presented very promising results, showing a high bioactive potential for all plant extracts. In the TBARS assay, E. globulus and O. vulgare stood out with lower EC 50 values, followed by T. vulgaris and S. officinalis . In turn, in the OxHLIA assay, for Δ t 60 min and Δ t 120 min, the excellent antioxidant capacity of S. officinalis and T. vulgaris was also evidenced, respectively. In addition, the evaluation of the antimicrobial activity highlighted the sample of G. glabra , both at the bacterial and fungal levels. Overall, it was possible to prove the great bioactive potential of the E. globulus , O. vulgare , S. officinalis , T. vulgaris and G. glabra extracts, and to highlight them as promising options for exploitation in the food industry. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by FCT, P.I., through the institutional and individual scientific employment program-contract for L. Barros and J. Pinela’s (CEECIND/01011/2018) contracts, respectively; research contract of C. Caleja (Project AllNatt, POCI- 01-0145-FEDER 030463) and E. Pereira (Project Mobilizador Norte-01-0247-FEDER-024479: ValorNatural®); to FEDER-Interreg España-Portugal program for financial support through the project TRANSCoLAB 0612_TRANS_CO_LAB_2_P, ERDF, through the Incentive System to Research and Technological development, within the Portugal2020 Competitiveness and Internationalization Operational Program for the financial support to BIOMA(POCI_01_0247_FEDER_046112); ERDF through the Regional Operational Program North 2020, within the scope of Project GreenHealth (Norte-01-0145-FEDER-000042). info:eu-repo/semantics/publishedVersion