effect of two blue green algae and tragacanth coated seed in maize under salinity stress

Soil salinity gradually become a major problem in arid and semiarid regions of the world. seed coating through biomaterials is a new method that maintains humidity around the seed. the aim of this study is to use absorbing biocompounds to increase the percentage of germination and improving growth of zea mays l. under salt stress. the experiment was conducted with maize seed which coated with tragacanth, tragacanth + anabaena and tragacanth + pseudo anabaena when exposed to 0, 120 and 160 mm nacl per kg of cocopeat. all seed treatments effectively promoted seed germination percentage in 160 mm nacl. seed coating with tragacanth led to a significant increase of growth indices compared to the noncoated seeds under salt stress. while, the combination of tragacanth with anabaena or peusodoanabaena reduced the growth parameters. coating treatment of maize seeds resulted in decreasing of na content in the plants compared to the plants from noncoated seeds. the results suggested that maize seed coating with tragacanth could improve na tolerance in the plants associated with a positive regulation of the seed germination and plant growth.