In order to evaluate the effects of seed priming with salicylic acid (SA) (0, 2, 10, and 20 mM) to increase salt tolerance (0, 50, 100, 150, and 200 mM NaCl) in medicinal plant Dracocephalum moldavica at seed germination, an experiment was conducted as factorial in a completely randomized design with four replicates. The assessed parameters included germination percentage and rate, length, dry weight, lipid peroxidation, electrolyte leakage, and the activity of catalase, ascorbate peroxidase, and guaiacol peroxidase of the seedlings. Results revealed the values of germination indices significantly decreased with increasing salinity levels. Nevertheless, seed priming with SA (2 mM) significantly mitigated the adverse effects of salinity in D. moldavica. Under salinity and at this level of SA priming, seed germination percentage increased by 24% and 75% at 100 and 150 mM compared to exclusive salt stress. Also, germination rate augmented by SA priming up to 9.2% at 100 mM and 2 folds at 150 mM NaCl. The values of weight (+ 9.1% at 100 mM and +8 folds at 150 mM) and length (+12.5% at 100 mM and + 15.1% at 150 mM NaCl) of seedlings significantlyincreased by SA priming compared to the exclusively salt-stressed ones. SA priming increased antioxidant enzymes activities while it decreased the level of lipid peroxidation and ion leakage in the seedlings of D. moldavica. As a conclusion, SA improved seed performance in D. moldavica under salt stress by reduction of detrimental effects of oxidative stress. Manuscript profile

In order to study the effect of silicon nutrition to increase salt tolerance in black bean variety of Phaseolus vulgaris, 12-day-old seedlings were treated with NaCl (0 and 50 mM) and NaCl (50 mM) + silicon (0.5 or 3 mM) in the green house for four weeks. The analyzed parameters were fresh and dry weights, total chlorophyll and free proline concentrations, relative water content (RWC) and electrolyte leakage in the leaves, and the concentrations of Na+ and K+ in the shoots and roots. Salt stress decreased the values of fresh (39.3%) and dry weight (48.4%), total chlorophyll (20.9%), K+ (60.6% in the roots; 20.3% in the shoots) and RWC (50%). Moreover, the level of free proline (19%), electrolyte leakage (2.4 folds) and Na+ concentration (4.6 folds in the shoots; 3.8 folds in the roots) significantly increased. However, silicon (particularly at 3 mM) ameliorated the deleterious effects of NaCl. At this case and compared to exclusively salt stress, the fresh and dry weights were increased by 20.3 and 66%. Also, the content of total chlorophyll (21%), RWC (83%) and K+ (21% in the shoots, 90% in the roots) augmented, but electrolyte leakage (38%) and the content of Na+ decreased (39.7% in the shoots, 27.8% in the roots). Generally, current data suggested silicon enhanced salt tolerance in black bean plants by reducing the entrance of Na+ and maintaining the level of K+ in the salinized tissues. Besides, it improved the water status, membrane integrity and function of photosynthetic machinery under salinity. Manuscript profile

Pistachio suffers from some physiological disorders such as fruit abscission, endocarp lesion, blankness, non-split, early-split and deformed nuts. In this experiment, the effects of calcium nitrate (2 gr/lit), calcium chloride (2 gr/lit), boric acid (200 ppm) and their combination treatments were investigated on physiological disorders of ‘Kaleh-Ghoochi’ pistachio. Foliar application was applied one week earlier and two weeks later than full bloom. Then, physiological disorders and enzyme activities, such as catalase (CAT), poly phenol oxidase (PPO), peroxidase (POD), phenylalanine ammonilyase (PAL) and total phenol level of nut-shells and proline level of leaves were tested. Results specified that all applied treatments diminished fruit abscission. Also, all treatments, excepting boric acid, diminished endocarp lesion and non-split nut disorders but there were no considerable differences between the treatments. Results specified that all applied treatments decreased the blank nut but there were no considerable differences between the treatments. In this research, the lowest deformed nuts with 10.38 percent and early split nut with 2.48 percent were observed by application of both calcium nitrate and boric acid. Meanwhile, the highest split nuts with 56.55 percent were obtained by application of calcium nitrate and boric acid. Generally, all treatments especially use of both calcium nitrate and boric acid diminish the catalase, poly phenol oxidase, peroxidase, and phenylalanine ammonilyase enzymes activities and moreover total phenol of nut-shells and proline of leaves. Manuscript profile