Effect of pretreatments on seed germination of musk rose (Rosa moschata Herrm.)

Abstract

We investigated effects of different chemical pre-treatments on seed propagation in musk rose (Rosa moschata Herrm.), an important Himalayan medicinal and aromatic climbing shrub. The seeds were pre-treated with potassium nitrate (150, 300, 450, 600 mM) or polyethylene glycol-PEG 8000 (12.5, 25.0 mM) for 24 or 48 hours. The seed pre-treatments were carried out at 15 °C or 25 °C in a seed germinator. The pre-treatment with potassium nitrate (300, 450 or 600 mM) for 48 h at 15 °C resulted in significantly (P ≤ 0.05) higher germination than the control and other treatments. The seed germination in treatment with 600 mM potassium nitrate (39.71 %) for 48 h at 15 °C was 34 fold higher than in the control (1.16 %). Further, the rate of seed germination (Timson’s Index) was also significantly higher in the potassium nitrate treatments than the control and other treatments. The pre-treatment was found more effective in case of seeds stored for 26 months than the one stored for 13 months. Among the other treatments, pre-treatment with 12.5 mM PEG 8000 for 24 h at 25 °C resulted in significantly higher germination (21.83 %) than the control. The germinating seeds from the treatments successfully established in seedlings and mature plants subsequently. Results of the present study thus suggest the pre-germination seed treatment with 600 mM potassium nitrate solution for higher, synchronous and rapid germination in musk rose for a large scale propagation of this economically and ecologically important Himalayan plant.