The leaf area, fresh and dry matter, and water content in the roots and shoots of broad bean were significantly reduced with a rise in salinity. The protein components in the roots and shoots decreased in response to salinity, whereas the proline content significantly increased. The sodium content in both roots and shoots increased with increasing salinity, whereas potassium and calcium decreased. Salinity induced an increase in total amino acids and ammonia.Spraying with salicylic acid (SA) increased the three growth parameters, stimulated the synthesis of protein at all salinities, retarded the accumulation of proline, retarded the accumulation of Na + and increased the content of K + and Ca 2+. The total content of amino acids was about 1.6-fold the untreated control and there was a drastic increase in the content of threonine and serine.The electrophoretic pattern of SA-treated seedlings showed 21 polypeptides compared to 12 in the salt-treated ones. Salinity plus SA resulted in the disappearance of 4 polypeptides. In addition, two peptides with molecular masses of 99 and 102 kDa appeared in the gel in both NaCl-treated seedlings and NaCl+SA-treated seedlings.

Strategic implementation of vermicompost as safe biofertilizer besides defensing saline soils offer dual function solving problems in developing countries. The current study aims to utilize vermicompost (VC) for amelioration of 200mM NaCl in Vicia faba Aspani cultivar and investigate the molecular role of salt overly sensitive pathway (SOS1). The experiment was conducted following a completely randomized design with three replicates. Treatments include 0; 2.5; 5; 10; 15% dried VC intermingled with soil mixture (clay: sand; 1:2) and/or 200 mM NaCl. The results show that salinity stress decreased broad bean fresh and dry weight; and K+/Na+. However, malonedialdehyde and H2O2 contents; increased. Application of 10% VC and salinity stress increases Ca2+ (41% and 50%), K+/Na+ (125% and 89%), Mg2+ (25% and 36%), N (8% and 11%), indole acetic acid (70% and 152%) and proteins (9% and 13%) for root and shoot, respectively, in comparison to salt treated pots. Moreover, all examined enzymatic antioxidants and their substrates increased, except glutathione reductase. A parallel decrease in abscisic acid (75% and 29%) and proline (59% and 58%) was also recorded for roots and leaves, respectively. Interestingly, the highly significant increase in gene expression of SOS1 (45-fold) could drive defense machinery of broad bean to counteract 200 mM NaCl.

The present study describes the response of Zea mays to hematite nanoparticles (NPs) using five concentrations ranged from 500 to 8000 mg kg −1 , and Cd 2+ concentrations (110 or 130 mg kg −1 Cd 2+ ) only or combined with 500 mg kg −1 NPs, using soil culture. The endpoints measured were root/shoot growth, elements uptake, ultra-structural alterations, lipid peroxidation, some antioxidant enzyme activities, and their relative gene expressions. The results indicated that hematite NPs exhibited a dual behavior, in which 500 mg kg −1 NPs significantly enhanced maize growth, while 4000 and 8000 mg kg −1 NPs significantly increased lipid peroxidation and superoxide dismutase (SOD) activity displaying positive correlation with SOD expression in shoots (r = +0.472, p < .05). Ultrastructure micrographs revealed the appearance of aggregated NPs inside the vacuoles. The stunted growth, perturbed ultra-structure, and high lipid peroxidation were used as toxicity biomarkers for Cd 2+ . However, combined treatments of 500 mg kg −1 NPs and Cd 2+ significantly stimulated growth and glutathione reductase activity, while significantly reduced catalase (CAT) activity displaying positive correlation with CAT expression in roots (r = +0.694, p < .01). In conclusion, hematite NPs could alleviate Cd 2+ toxicity not at the level of antioxidant defense, but by affecting mechanisms of Cd 2+ detoxification.

Changes in growth parameters, sodium accumulation, element composition, and antioxidant enzyme activity of habitat-indifferent Salsola drummondii during the vegetative stage were investigated. Our results showed that S. drummondii grew very well in up to 500 mM NaCl. There were no significant differences in the water content and biomass of shoots, roots, and leaves between the control and plants treated with 500 mM NaCl (equivalent to seawater salinity). However, chlorophyll and carotenoid content was reduced at higher salinities, which was associated with a significant increase in H2O2 and malondialdehyde. Our results revealed that S. drummondii can translocate Na+ from the roots to shoots, with Na+ content in the shoots being higher than that in the roots. In contrast, the S. drummondii plants treated with NaCl exhibited a significant decrease in the levels of essential ions in different plant organs. Proline concentration significantly increased with increasing salinity and significant changes were observed in guaiacol peroxidase, catalase, and ascorbate peroxidase levels under different salinity treatments. The activity of antioxidant enzymes and proline accumulation in S. drummondii plants was correlated with enhanced salt tolerance. Our findings provide novel insights into the salt tolerance ability of S. drummondii.

The objective of the current study was to find out the effect of aluminum on the seedlings pre-treated by two levels of boron concentrations 4μM or 32μM grown in hydroponic solution of Al from 100-500μMAl for 3 days. Data revealed that Al had a negative effect on fresh, dry weight, water content, carbohydrate, protein and amino acids including proline constituents and changes in protein profile were analyzed of fourteen day-old Al-tolerant (‘Sakha 93’) cultivar of Triticum aestivum. The effect of boron treatment was pronounced at 32μM B level. Pretreatment of 4µM B and exposure to 500 µM Al revealed that insoluble protein increased soluble, total protein and total soluble sugars decreased in comparison to Al treatment only. Levels of amino acids most notably proline, the glutathione forming amino acids cysteine, glycine and glutamic and the branched chain amino acids (BCAAs) leucine, isoleucine and valine were increased under Al stress. The obtained results showed the high resistance of ‘Sakha 93’ cultivar to aluminum stress. Aluminum detoxification coincides with increased TSS, TP, Pro, BCAAs contents and polypeptides in the root to cope with alleviation of Al-stress; boron may have a role in this concern.

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This study evaluates the influences of nickel and ozone exposure individually and/ or in combination on growth performance, antioxidant activity and genes up regulation of two rice cultivars Sakha 101 and Giza 178. Ni treatment at high doses (100 µM Ni) and 75 ppb O 3 alone reduced the fresh weight, mineral content, membrane integrity and Rubisco content. There was an increase in SOD and APX activity in the shoots of rice cultivars, whereas, there was a decrease in GR and GST in the roots and shoots. In contrast combined stresses appeared to be stimulatory for growth and mineral contents, Rubisco content and antioxidant enzymes. Nonspecific lipid transfer protein and transmembrane protein genes were up regulation in rice cultivars in response to Ni stress. Carotenoid cleavage dioxygenase is upregulated in response to ozone stress; RNA pseudouridine synthase, heat shock proteins and cytochrome P450-like were upregulated in response to combined stresses. The results revealed that the interactive effects of both stresses were antagonistic on growth parameters and antioxidant activities to overcome the adverse effects of both pollutants.

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