Effect of drought and salinity stresses on germination characteristics of indigo (Indigofera tinctoria)

Indigo (Indigofera tinctoria) is one of the legume family which its flowers because of producing a blue color and having wound healing properties is widely used in traditional medicine and cosmetics industries. Due to reduction of water resources and agricultural lands salinization، evaluation of tolerance of this plant to drought and salinity stress conditions at germination stage was investigated. In order to investigate the effects of drought stress caused by PEG 6000 (0، -2، -4، -6 and -8 bar) and salinity stress induced by NaCl (0، 100، 200، 300، 400 and 500 mM)، two separate experiments were carried out. According to the results، different levels of drought and salinity had significant effects on all germination indices، so that germination percentage in control treatments was highest in both experiments (90. 1 and 90 percent respectively) and was lowest at -8 bar and 500 mM treatments (17. 7 and 72. 5 percent، respectively). According to the results، it seems that this plant has a good tolerance to drought and salinity stresses at germination stage.