Effect of Co-inoculation of Endophytic Fungus Piriformospora Indica and Azospirillum Strains on Some Physiological Traits, Nutrient Absorption and Grain Yield of Wheat (Triticum aestivum cv. Sardari) Under

Bacteria of the genus Azospirillum and mycorrhizal fungi, well known as plant growth promoting microorganism, are considered to can improve plant tolerance to environmental stresses such as drought and salinity conditions. A factorial randomized complete block design replicated in three times was conducted to test the effects of Azospirillum strains and fungus Piriformospora indica under increasing salinity levels on wheat seedlings growth, nutrient absorption as well as some physiological traits. Treatments were consisted of five bioinoculants (P. indica, salt adapted and non-adapted Azospirillum strains, dual inoculation of the both microorganisms and non-inoculated treatment as control) as well as four salinity levels (0.2, 4, 8 and 12 dS m-1). Singly or co-inoculation of wheat with P. indica and salt-adapted and non-salt adapted Azospirillum strains lead to a higher increase in grain yield, N and P concentrations, protein content as well as total photosynthetic pigments, both under salinity and normal conditions. Plant inoculated with salt-adapted Azospirillumspp., under salinity, had the higher nutrient uptake (P and N), protein content as well as total photosynthetic pigments. From obtained result of the present study use of endophytic plant growth promoting microorganism singly or in combination depend on induced salinity levels is different. Under non-salinity dual combination of both microorganisms was more effective in enhancing grain yield compared to other treatments. While under the lower level of salinity (EC=4) microorganisms, both in singly or in combination, had a same effect on grain yield, under severe salinity (EC=12) singly inoculation of each microorganisms had a better performance on grain yield.