Effects of salt stress on volatile compounds, total phenolic content and antioxidant activities of Salvia mirzayanii

AbstractSalvia mirzayanii is a medicinal and aromatic plant belonging to the Lamiaceae family, which is an endemic plant in Iran. In this study, the effects of different salt concentrations on total phenolic content, antioxidant activities and volatile components of the aerial parts of S. mirzayanii were studied. The results showed that total phenolic content increased with the increase in salt concentration. The increase was more pronounced under moderate salinity (3.8mg GAEg−1 DW at 6.8dSm−1 NaCl). Plants grown at 6.8dSm−1 NaCl displayed the highest DPPH˚ scavenging activity with the lowest IC50 value (2.13mgml−1) compared to the control. The volatile components were identified and analyzed by HS (headspace)-GC–MS using the Combi PAL System technique. The main components of control plants were α-terpinyl acetate, 1,8-cineole and bicyclogermacrene. The proportions of these main compounds were differently affected by salinity stress. The results showed that the synthesis of both total phenolic and some important volatile components was induced by moderate salinity

Ameliorative effects of salicylic acid on mineral concentrations in roots and leaves of two grapevine (Vitis vinifera L.) cultivars under salt stress

Salicylic acid (SA) acts as an endogenous signal molecule, synchronizing plant responses under abiotic stress and a component of tolerance in plants. The current study investigates the effects of SA on mineral nutrient concentrations in two grapevine (Vitis vinifera L.) cultivars, 'Qarah Shani' and 'Thompson Seedless' under NaCl stress. Grapevine rooted cuttings were planted in pots, containing a mixture of perlite and cocopeat (1:1 v/v) and placed in an open hydroponic system. Plants were exposed to five levels of salinity 0, 25, 50, 75 and 100 mM NaCl and four levels of SA 0, 100, 200 and 300 mg∙L-1. Results indicated that foliar spray with SA improved nutrient uptake by grape roots. Plant’s leaves and roots Na+ and Cl- contents increased significantly, and NO- 3-N, K+, Na+, Ca2+, Mg2+, Zn2+, Fe2+ and also K+/Na+ selectivity ratios decreased in both cultivars in response to salt treatments. Application of SA significantly reduced Na+ and Cl- accumulation in leaves and roots in both cultivars and it increased NO3-N, K+, Ca2+, Mg2+, Zn2+ and Fe2+ contents under NaCl stress. Therefore, SA could mitigate the detrimental effects of salinity on accumulation of harmful ions and improve the absorption of essential and beneficial elements in grapevine under salinity.

How exogenous nitric oxide regulates nitrogen assimilation in wheat seedlings under different nitrogen sources and levels

Nitrogen (N) is one of the most important nutrients for plants and nitric oxide (NO) as a signaling plant growth regulator involved in nitrogen assimilation. Understanding the influence of exogenous NO on nitrogen metabolism at the gene expression and enzyme activity levels under different sources of nitrogen is vitally important for increasing nitrogen use efficiency (NUE). This study investigated the expression of key genes and enzymes in relation to nitrogen assimilation in two Australian wheat cultivars, a popular high NUE cv. Spitfire and a normal NUE cv. Westonia, under different combinations of nitrogen and sodium nitroprusside (SNP) as the NO donor. Application of NO increased the gene expressions and activities of nitrogen assimilation pathway enzymes in both cultivars at low levels of nitrogen. At high nitrogen supplies, the expressions and activities of N assimilation genes increased in response to exogenous NO only in cv. Spitfire but not in cv. Westonia. Exogenous NO caused an increase in leaf NO content at low N supplies in both cultivars, while under high nitrogen treatments, cv. Spitfire showed an increase under ammonium nitrate (NH4NO3) treatment but cv. Westonia was not affected. N assimilation gene expression and enzyme activity showed a clear relationship between exogenous NO, N concentration and N forms in primary plant nitrogen assimilation. Results reveal the possible role of NO and different nitrogen sources on nitrogen assimilation in Triticum aestivum plants

Remote Video-to-Video Eye Telemonitoring Use Case for Glaucoma Patients

Part 1: IIVC WorkshopInternational audienceGlaucoma is the second leading cause of blindness globally and the second most common cause of avoidable visual impairment. It also holds a record in noncompliance to therapy from the patients in up to 50% of the subjects treated with anti-glaucoma eye drops. LiveCity e-Health is a European research program, which aims to provide better treatment and follow up of glaucoma patients at their home, through telemonitoring with high definition video-to-video (v2v) communication from the University Hospital. Secondly, it aims to reduce the cost of health and improve the city environment by decreasing the number of visits to the Hospital. For this purpose, a software application has been developed; the latter is easy to use for elderly people at home, and capable of keeping the medical history and digital records of every patient in the Glaucoma Department. In addition, a specific web camera with snapshot ability of high quality photo of the eye has utilised. Two patients have been initially enrolled in the study and the preliminary results are so presented