The effect of duration of moist chilling, concentration, type and application time nitrogen compounds on seed germination and seedling growth of Kelussia odoratissima Mozaff

Kelussia odoratissima Mozaff. is one of the pasture and native plants in Iran that has a special value. Seeds of this species have shown dormancy that causes reduction of seed germination this plant. Therefore in this research, 2 factorial experiment with completely randomized design and with 3 replication carried out to evaluate the effect of duration of moist chilling, in 7-level, concentration of nitrogenous compounds (Potassium nitrate and Thiourea) in 3-level and application time nitrogenous compounds in 2-level (before and after chilling), on seed germination capacity and germination velocity. Also a factorial experiment design performed to evaluate the effect of the type, concentration and application time of the same nitrogenous compounds on growth parameters of developed seedlings from 10 weeks pre-chilled seeds. Results of research showed that 10 week moist pre-chilling has significant effect on seed germination this plant and increased seed germination and germination velocity. Concentrations of 0.2 % potassium nitrate, or 0.5 % thiourea had positive effect, but concentrations 0.6% potassium nitrate or 5% thiourea had a negative effect on seed germination. Treated with 0.2 % of potassium nitrate had no effect on root length and dry weight but increased length, fresh weight and dry weight of stems and root fresh weight in the level of 5 percent in compared to control. In contrast the concentration of 0.6 % potassium nitrate, all of these traits decreased in compared to control. In this study both thiourea concentrations inhibited seedling growth.