Author/Authors :
Ali Mohammadizad، Hossein نويسنده tment of Horticultural Sciences, Faculty of Agriculture, Islamic Azad University, Science and Research Branch, Tehran, Iran , , Khazaei، Iraj نويسنده Department of Horticultural Sciences, Faculty of Agriculture, Islamic Azad University, Karaj Branch, Karaj, Iran , , Ghafari، Moslem نويسنده Department of Horticultural Sciences, Faculty of Agriculture, Islamic Azad University, Science and Research Branch, Tehran, Iran , , Fatehi Sinehsar، Mir Fazel نويسنده Department of Horticultural Sciences, Faculty of Engineering, Islamic Azad University, Mianeh Branch, Mianeh, Iran , , Barzegar، Roghaieh نويسنده Department of Horticultural Sciences, Faculty of Agriculture, Islamic Azad University, Science and Research Branch, Tehran, Iran ,
Abstract :
High salinity in soil or irrigation water and drought are common environmental problems affecting seed germination and plant growth especially in arid and semi-arid regions. Seed germination is the most sensitive stage to abiotic stress. Iranian catnip (Nepeta persica) is one of the important medicinal plants. This study was carried out in order to investigate the effects of osmotic and drought stresses at critical stage of plant life (seed germination). The effect of salt and drought stresses at the levels of 0, -3, -6, -9 and -12 bars induced by sodium chloride (NaCl) and polyethylene glycol (PEG) on germination and seedling growth of Iranian catnip (Nepeta persica). The objective was to determine the most sensitive component to stress. Germination rate and percentage (GR and GP), root length (RL), shoot length (SL), root to shoot ratio (R/S) and seedling fresh weights (SFW) were measured. Results showed that drought and salinity decreased GP, root length, shoot length and SFW significantly and seedling growth was more sensitive than seed germination. In addition, R/S was significantly affected by drought stress and water potential decreased, R/S increased which shows shoot growth is more sensitive than root growth to both salinity and drought stresses.
