عنوان مقاله [English]
In order to determine the effect of different levels of salinity (EC=1.6, 3.2, 4 and 0.8 dS/m as control) using sodium chloride on physiological parameters and also some growth indices in the three grafted-pear rootstocks (OHF69, pyrodwarf and one seedling rootstock) in grafting with Daregazi, Louise Bonne and William Duchesse scions, a pot experiment was carried out as factorial arrangement based on randomized complete block design with three replications in Horticulture research station of Kamalabad/Karaj in spring of 2015. In the present work, different indices of susceptibility and tolerance for all studied parameters were identified and also rank mean (Ṝn) and standard deviation of ranks (SDR) of all mentioned parameters were measured. Results of this study showed that among all studied parameters the reduction of chlorophyll or SPAD value (20% reduction in saline conditions) was higher than other parameters. Among all grafted-pear rootstocks, seedling rootstock in grafting with Louise bonne showed comparative advantage in terms of length, diameter, FV/FM and the amount of chlorophyll or SPAD value compared to other grafted-pear rootstocks. Also, pyrodwarf rootstock in grafting with Louise bonne showed in saline conditions, further reducing the parameters of length, diameter, leaf area, Fv/Fm and chlorophyll or SPAD value compared to other grafted-pear rootstocks. In the present work, seedling rootstock in grafting with Louise Bonne was identified as the most salt tolerant between studied grafted-pear rootstocks, while pyrodwarf rootstock in grafting with Louise Bonne as the most sensitive.