Phosphorus uptake and partitioning in stem elongation and anthesis growh stages of wheat and barley as influenced by fertilizer P rate and inoculation with Streptomyces sp. bacterium

In this study, concentration, absorption and distribution of phosphorus, as most restrictive essential element after nitrogen, in these two stages of wheat and barley were studied.The experimental factors were fertilizer P rate (0, 8.4, 16.8, 25.2 and 33.6 mg P per kg dry soil equal to 0, 20, 40, 60 and 80 kg P ha-1), inoculation or uninoculation with Streptomyces sp. bacterium and crop (wheat cultivar Morvarid and barley cultivar Sahra). In both growth stages of SE and Ant, P concentration was increased linearly in all plant parts by increasing the amount of applied fertilizer phosphorus. In all fertilizer P rates, plant parts in terms of P concentration were arranged as leaf > shoot > total plant > stem > root, and in term of P content were arranged as root< leaf< stem< shoot< total plant. Inoculation with Streptomyces isolate increased root P concentration in SE and leaf, shoot and whole plant P concentration in Ant, P accumulation in these parts of plants and stem in Ant, significantly. In both growth stages, P concentration and accumulation in different parts of plant except phosphorus has accumulated in the stem, in barley was more than wheat. Results showed that P allocation coefficient to different organs has higher stability than P concentration and accumulation. Findings of this study indicated a strong relationship between the amount of accumulated P in whole plant in SE and Ant with grain yield in two crops. This relationship well described by a segmented linear-plateau function.