Aims: Germination stage is one of the most sensitive stages to drought stresses and if the plant is able to tolerate stresses in this stage, it can pass the later growth stages. Priming could improve germination of seeds under stress.
Materials and Methods: Experiment was carried out using a randomized complete block design. 25 seeds were placed in petri dish under drought stress with polyethylene glycol 6000 in three levels of 0, -6 and -12 bar. After 14 days, it was found that the germination percent in these seeds was low (>40%). Then nano priming was used to improve seed germination attributes. Treatments were; control, silver nanoparticles with the concentrations of 25, 50 and 75%.
Findings: Data analysis of variance indicated that influence of nano priming, drought stress, and their interaction was significant on root and shoot length, wet and dry weight, vigor index, allometric coefficient and mean germination time (p≤0.01). Results showed that PEG stress had a negative effect on seeds germination. And an increase of silver nanoparticles concentration improves F. ovina seed germination and seedling traits. The maximum of GP (86%), SG (6N/D), Vi (5), AC (6) and MGT (7.08d) were recorded for seeds nano primed in the stress of 0 level.
Conclusion: Nano-priming is an impressive technique to the betterment of seedlings germination and growth of F. ovina. In the most studied indices, nano-priming 75% had the greatest influence. Before planting to restore of rangelands, to promote the establishment and growth of planted F. ovina it is recommended to prime seeds with nano-silver particles.

Aim: The effects of potassium silicate nanoparticles (PSN) and effective microorganisms (EM) were studied on the growth of alfalfa (Medicago sativa L.) and sainfoin (Onobrychis sativa Lam.) and soil.
Materials & Methods: Split-split plot in a complete randomized block design with three replications was used for this experiment. Planting time in two seasons (autumn and spring) as the main plot, facilitators in five levels, including control, PSN (500 and 1000mg/lit), and EM (1 and 2%), as sub-plots and two legume species as sub-sub plot were studied in the field. In the four-leaf step of plants, PSN and EM were added in three steps as a solution.
Findings: The highest amount of plant viability (80, 82.22%), height (59, 68.33cm), basal diameter (13.33, 16.66cm), canopy cover (993.33, 1242.66cm²), leaf area index (67.79, 84.93cm²), relative water content (70.46, 88.32%), chlorophyll (0.87, 0.72mg.g^-1), photosynthesis rate (27.29, 28.49µmolco₂.cm^-2s^-1), number of inflorescence (57.33, 56N/m²) and 1000-grain weight (33.30, 3.89g.m^-2) were in sainfoin (EM2%) and alfalfa (PSN1000mg/lit), respectively. Total biomass (423.87 and 374.50g.m^-2) was maximum in PSN1000mg/lit for both species. EM and PSN caused desirable effects on the soil characters of species substrates (p<0.01). The maximum value of all studied soil characters belonged to PSN1000. Additionally, autumn sowing compared to spring planting enhanced the studied traits of planted species and their substrate soil.            
Conclusion: The usage of appropriate PSN and EM concentration in this study to restore dry-farming lands and improve species growth and forage yield can be suggested.