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Background Salinity as a most significant environmental challenges affects the growth and productivity of plants worldwide. In this study, the ionic and iso-osmotic effects of salt stress were investigated in Aeluropus littoralis L., a halophyte grass species from Poaceae family, by cDNA-amplified fragment length polymorphism (cDNA-AFLP) technique. To dissect the two different effects (ionic and osmotic) exerted by salt stress, various ionic agents including 200 and 400 mM sodium chloride (NaCl), 200 and 400 mM potassium chloride (KCl) as well as 280 and 406 gl − 1 (− 0.9 and − 1.4 MPa) polyethylene glycol 6000 (PEG) as their iso-osmotic concentrations were applied. Results Application of KCl and PEG significantly reduced the fresh weight (FW) of A. littoralis seedlings compared to control while NaCl treatment markedly enhanced the FW. At the transcriptome level, different observations of changes in gene expression have been made in response of A. littoralis to ionic and osmotic stresses. Out of 69 transcript derived fragments (TDFs), 42 TDFs belong to 9 different groups of genes involved in metabolism (11.6%), transcription (10.2%), ribosomal protein (8.7%), protein binding (8.7%) transporter (5.8%), translation (5.8%), signal transduction (4.3%), nucleosome assembly protein (2.9%) and catabolism (2.9%). The 44 and 28 percent of transcripts were expressed under ionic stress (NaCl-specific and KCl-specific) and osmotic stress (common with NaCl, KCl and PEG), respectively which indicating a greater response of plants to ionic stress than osmotic stress. Expression pattern of eight candidate TDFs including; SYP81 , CAND1 , KATN , ISB1 , SAMDC , GLY1 , HAK18 and ZF30 was evaluated by RT-qPCR at high salinity levels and recovery condition. Conclusion Differential regulation of these TDFs was observed in root and shoot which confirm their role in salt stress tolerance and provide initial insights into the transcriptome of A. littoralis . Expression pattern of ionic and osmotic-related TDFs at A. littoralis can be taken as an indication of their functional relevance at different salt and drought stresses.

Context: Satureja khuzistanica Jamzad. (Lamiaceae), is known for its antifungal and antioxidant compounds, especially rosmarinic acid (RA). Objective: The study examines the effect of elicitors on RA production and phytochemical properties of S. khuzistanica. Materials and methods: In vitro plants were treated with methyl jasmonate (MeJA) and multi-walled carbon nanotubes (MWCNTs). In vivo plants were treated with MWCNTs and salicylic acid (SA). RA was measured by HPLC. Catalase (CAT), guaiacol peroxidase (POD) and ascorbate peroxidase (APX) were quantified. DPPH and b-carotene were assayed in in vivo extracts. The antifungal effects of extracts were evaluated against Fusarium solani K (FsK). Results: The highest RA contents of in vitro plants were 50 mg/L MeJA (140.99 mg/g DW) and 250 mg/L MWCNTs (140.49 mg/g DW). The highest in vivo were 24 h MWCNTs (7.13 mg/g DW) and 72 h SA (9.12 mg/g DW). The maximum POD and APX activities were at 100 mg/L MeJA (5 and 4 mg protein, respectively). CAT had the highest activities at 50 mg/L MeJA (2 mg protein). DPPH and b-carotene showed 50% and 80% inhibition, respectively. The FsK aggregation was the lowest for in vitro extract in number of conidia [1.82 Â 10 10 ], fresh weight (6.51 g) and dry weight (0.21 g) that proved RA inhibitory effects. The callus reduces FsK growth diameter to 2.75 on the 5th day. Discussion and conclusions: Application of MeJA, SA, and MWCNTSs could increase RA in S. khuzistanica and highlighted potential characteristics in pharmaceutical and antifungal effects.

Climate change has caused breeders to focus on varieties that are able to grow under unfavorable conditions, such as drought, high and low temperatures, salinity, and other stressors. In recent decades, progress in biotechnology and its related tools has provided opportunities to dissect and decipher the genetic basis of tolerance to various stress conditions. One such approach is the identification of genomic regions that are linked with specific or multiple characteristics. Cereal crops have a key role in supplying the energy required for human and animal populations. However, crop products are dramatically affected by various environmental stresses. Barley (Hordeum vulgare L.) is one of the oldest domesticated crops that is cultivated globally. Research has shown that, compared with other cereals, barley is well adapted to various harsh environmental conditions. There is ample literature regarding these responses to abiotic stressors, as well as the genomic regions associated with the various morpho-physiological and biochemical traits of stress tolerance. This review focuses on (i) identifying the tolerance mechanisms that are important for stable growth and development, and (ii) the applicability of QTL mapping and association analysis in identifying genomic regions linked with stress-tolerance traits, in order to help breeders in marker-assisted selection (MAS) to quickly screen tolerant germplasms in their breeding cycles. Overall, the information presented here will inform and assist future barley breeding programs.