Improvement of seed germination traits in in Scots pine (Pinus sylvestris), Black pine (Pinus nigra) and Turkish pine (Pinus brutia) by using the polyethylene glycol pre-treatment

Proper Seed germination and establishment is one of the most important issues in pre-planting treatments. Seed osmopriming is proposed as a pre-emergence treatment to increase the characteristics germination and seedling establishment, especially in unfavorable conditions. The effects of osmopriming on germination (germination percentage, maximum daily average germination, germination rate, mean germination time, germination value) of Scots pine, black pine and Turkish pine under controlled conditions in order to determine the best treatment were investigated in this research. A factorial experiment was conducted as a completely randomized design with three replicates. Main factors included the time (0, 1, 2 and 3 days) and osmotic potential (0.8, 1.2 and 1.5 MPa) using polyethylene glycol 6000. The results indicated that there were significant differences between treatments on germination characteristics in all three species, and all studied traits were improved by osmopriming. The highest germination factors were recorded for Scots pine and black pine treated with 1day in concentrations of 0.8 MPa (polyethylene glycol 6000) and for Turkish pine were obtained with 2 days in the concentration of 1.2 MPa in compared with control treatment. So it can be suggested that in order to increase the quantity and quality of production in seedlings nursery of these species, the pre-planting treatments should be considered further