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Increased soil salinization, tightly related to global warming and drought and exacerbated by intensified irrigation supply, implies highly detrimental effects on staple food crops such as wheat. The situation is particularly alarming for durum wheat (DW), better adapted to arid/semi-arid environments yet more sensitive to salt stress than bread wheat (BW). To enhance DW salinity tolerance, we resorted to chromosomally engineered materials with introgressions from allied halophytic Thinopyrum species. "Primary" recombinant lines (RLs), having portions of their 7AL arms distally replaced by 7el1L Th. ponticum segments, and "secondary" RLs, harboring Th. elongatum 7EL insertions "nested" into 7el1L segments, in addition to near-isogenic lines lacking any alien segment (CLs), cv. Om Rabia (OR) as salt tolerant control, and BW introgression lines with either most of 7el1 or the complete 7E chromosome substitution as additional CLs, were subjected to moderate (100 mM) and intense (200 mM) salt (NaCl) stress at early growth stages. The applied stress altered cell cycle progression, determining a general increase of cells in G1 and a reduction in S phase. Assessment of morpho-physiological and biochemical traits overall showed that the presence of Thinopyrum spp. segments was associated with considerably increased salinity tolerance versus its absence. For relative water content, Na+ accumulation and K+ retention in roots and leaves, oxidative stress indicators (malondialdehyde and hydrogen peroxide) and antioxidant enzyme activities, the observed differences between stressed and unstressed RLs versus CLs was of similar magnitude in "primary" and "secondary" types, suggesting that tolerance factors might reside in defined 7el1L shared portion(s). Nonetheless, the incremental contribution of 7EL segments emerged in various instances, greatly mitigating the effects of salt stress on root and leaf growth and on the quantity of photosynthetic pigments, boosting accumulation of compatible solutes and minimizing the decrease of a powerful antioxidant like ascorbate. The seemingly synergistic effect of 7el1L + 7EL segments/genes made "secondary" RLs able to often exceed cv. OR and equal or better perform than BW lines. Thus, transfer of a suite of genes from halophytic germplasm by use of fine chromosome engineering strategies may well be the way forward to enhance salinity tolerance of glycophytes, even the sensitive DW. [ABSTRACT FROM AUTHOR]

Strawberry trees (Arbutus unedo L.) are naturally grown in particular Black Sea and Mediterranean regions of Turkey with great diversity due to continuous seed propagation for centuries. The trees differ in terms of most of the horticultural characteristics. We investigated the phenolic compounds and the biochemical and pomological characteristics of the fruits of eight strawberry tree selections naturally grown in the western part of Turkey. Significant differences were found among the genotypes in terms of their phenolic compounds and their biochemical and pomological characteristics. Among soluble sugars, fructose (11.63 g 100 g−1) was the dominant sugar, followed by glucose (6.10 g 100 g−1) and sucrose (1.44 g 100 g−1) for all the genotypes. Positive correlation was found between fruit weight and soluble sugar content. Malic acid was the major organic acid (0.67-2.33 g 100 g−1), and the second major organic acid in strawberry tree fruits was citric acid (0.25-0.87 g 100 g−1). Vitamin C content was an average of 56.22 g 100 g−1 for the eight genotypes. Among phenolic compounds, gallic acid was dominant (1.62-7.29 mg 100 g−1), followed by chlorogenic acid (1.23-3.14 mg 100 g−1), on an average basis.

The chemical composition, antioxidant properties and antibacterial activities of different extracts (water, ethanol, acetate ethyl and hexane) and essential oil from Platycladus orientalis leaves were analysed in this study. The essential oil was extracted by hydrodistillation, and its chemical composition was determined by gas chromatography coupled to mass spectrometry (GC-MS). The major components of the essential oil were a-pinene (40.2%), ß-phellandrene (9.3), a-cedrol (9.2%) and ß-caryophyllene (6.3%). Phytochemical analysis of crude extracts and essential oil revealed the richness of ethyl acetate and ethanolic extracts in total phenolic content (62.69 and 61.44 mg GAE/g DW, respectively). The antioxidant activities of all samples were evaluated by four different methods including total antioxidant activity (TAC), 1,1-diphenyl-2-picrylhydrazyl radical scavenging (DPPH), ABTS free radical scavenging activity (ABTS) and reducing power assay (RPA). Results showed that ethanol extract exhibited the highest antioxidant activity with all assays. The antimicrobial activity was evaluated by the disc diffusion method against five bacterial strains: Staphylococcus aureus CIP 53156, Bacillus subtilis CIP 5262, Micrococcus luteus CIP 5345, Salmonella enterica CIP 8039, and Escherichia coli CIP 53126. Results demonstrated that essential oil of P. orientalis leaves is more effective against the tested strains than extracts, especially against Micrococcus luteus and Staphylococcus aureus. This study argues the use of P. orientalis essential oil and ethanol extracts as a potential source of natural antioxidants and antimicrobial agents and supports the valorization of these natural substances in further application domains. [ABSTRACT FROM AUTHOR]

Lemon balm (Melissa officinalis L.) is one of the rare medicinal plants in Tunisia. It was found only in two sites in the north of Tunisia with a small number of plants. The study of germination under the NaCl and PEG effect showed that Tunisian lemon balm seeds were sensitive to saline and osmotic stress. Morphological and biochemical characterizations of Tunisian M. officinalis were performed. Results showed that the Tunisian populations presented plants with long, broad leaves and weak branching. The major constituent in leaf essential oil was germacrene-D with a percentage ranging from 29.17 to 24.6%, and the major fatty acids were polyunsaturated fatty acids, linoleic acid, ranging from 73.93 to 66.74%. The phenolic content of M. officinalis extract varied significantly among origins which could explain the high variation in antiradical scavenging activity. The evaluation of allelopathic activities showed that the extract of the lemon balm leaves presented an allelopathic effect with the majority of the tested seeds. [ABSTRACT FROM AUTHOR]

WRKY transcription factors, being involved in several biological roles, stimulus signaling, and stress response, could be interesting candidates to prospect, particularly in the Citrus unshiu (Satsuma mandarin) genome. Our approach, mainly based on computational analyses, led to the identification of 51 CiuWRKYs followed by their molecular characterization. Syntenic relationship analysis showed significant bias towards sweet orange and Arabidopsis chromosomes. Analyses of promoter region showed that CiuWRKY1 modulates gene transcription through W-box site targeting. The deduced CiuWRKY1 protein was moderately hydrophobic. A comparative in silico analysis among Arabidopsis thaliana and Citrus sinensis WRKYs allowed us to designate orthologous genes. Lacking available CiuWRKY1 expression data, the expression patterns of these orthologous genes indicated that CiuWRKY1 transcription would be modulated by various environmental and biotic constraints and growth regulator stimuli. Our results suggested that the characterization of the CiuWRKY genes in C. unshiu provides new information that can help characterize the molecular mechanisms underlying stress responses and cellular growth, and that CiuWRKY1 would be an interesting candidate to use in Citrus breeding technologies. [ABSTRACT FROM AUTHOR]