Tolerance comparison of four wild almonds to salinity in Chaharmahal and Bakhtiari province

Drought and salinity are the most important environmental stresses that are causing adverse effects on natural ecosystems. There are species among Iranian natural germplasm that are resistant to environmental harsh conditions. Restoring of degraded ecosystems، promoting of biodiversity and increasing of species richness will provide by identifying of these species. Almond species with broad ecological range have this capability. In order to compare the resistance of wild almond species to salinity stress and investigation on effect of aspect (geographical direction) on salinity resistant، seeds of Amugdalus Arabica، A. scoparia، A. haussknechtii and A. eleagnifolia were collected from north and south aspects from Karebas site in Chaharmahal and Bakhtiari province. Seeds were treated by cold-water stratification and then were planted in the nylon bags in green house. After two months، seedlings were experimented by using of sodium chloride with five levels of salinity (control، 25، 50، 75، 100 Mm)، by factorial experiment in completely randomized design with three replications. Results showed that the maximum amount of growth and biomass belonged to seedlings from south aspect. Control seedlings were grown 14 cm during the experimental period and the growth rate of seedlings under 100 mmol reduced to 8. 9 centimeters. By increasing of salinity، length and height increment of seedlings decreased. Increasing of salinity caused reduce in absorption of copper، zinc، iron، manganese and potassium and increase in uptake of magnesium، sodium، chlorine، nitrogen، calcium and proline concentration in the shoots of seedlings. Proline in control seedlings was 39 mg/g، by increasing of stress amount of proline received to 118. 4 mg/g in seedlings under salt stress of 100 mmol. Among the studied species، A. arabica had highest levels of growth factors، pigments concentration and uptake of necessary elements in facing of salinity stress، which sounds to be the most resistant species to salinity.