Abstract: The effects of various priming solutions on germination of freshly harvested Lolium multiflorum Lam. seeds were investigated. The results revealed that priming seeds in various concentrations of KNO3, KH2PO4 or polyethylene glycol for five days at 25°C with a 12 h photoperiod had no effect on dormancy release mechanism of annual ryegrass seeds although 1% KNO3 gave slightly increased germination percentage compared to untreated control. Inclusion of various concentrations of methyl jasmonate (MeJA), 1-aminocyclopropane-1-carboxylic acid (ACC) or 6-benzylamino-purine (BAP) into priming solution indicated that 100 μM BAP was the only treatment that improved germination rate while 1 μM ACC along with 500 μM BAP enhanced seedling emergence rate only. The possible reasons of the lack of reaction to the other plant growth regulators were also discussed.