Effect of Microbial Inoculation on Phosphorus Efficiency (PE) of Different Genotypes of Barley

Phosphorus (P) is regarded as the most important soil nutrient after nitrogen (N) for plant growth and development as it plays key roles in plant metabolism, structure and energy transformation. Also, although soil P is often abundant in both organic and inorganic forms, it is frequently a major or even the prime limiting factor for plant growth. Low phosphorus (P) availability is a major global global constraint to crop production. In most soils, soil and fertilizer P are easily bound by either soil organic matter or chemicals, and thus are unavailable to plants unless hydrolyzed to release inorganic phosphate. Phosphorus efficient plants play a major role in increasing crop yields due to shortage of inorganic P fertilizer resources, limited land and water resources, and increasing environmental concerns. Therefore, the development of P-efficient crop varieties that can grow and yield better with low P supply is a key for improving crop production. Enhancing P efficiency in plants can be achieved through enhancing P acquisition, utilization, or both.
In order to investigate the effect of microbial inoculation on phosphorus efficiency of different genotypes of barley, a glasshouse factorial experiment was conducted in a completely randomized block design with 10 barley genotypes and different phosphorus (P) treatments including control (P0), phosphate rock (RP), RP inoculated with phosphate solubilizing fungi (RP), RP inoculated with phosphate solubilizing bacteria (RP), RP inoculated with both fungi and bacteria inoculums (RPߡ), and soluble phosphate (PS) in three replications. After sieving (2 mm sieve), and, air - drying of soil samples, basal nutrients mixed thoroughly at the following soil test results. Then, soils placed in plastic pots (3 kg). The P treatments as (KH2PO4 and Rock Phosphate) 80 mg kg-1 soil added at the depth of 5-cm of soil. After 9 weeks the plants were harvested, grain dry weight (GDW) and grain P concentration measured and then content P (TP), P efficiency (PE), P acquisition efficiency (PACE) and P utilization efficiency (PUTE) were calculated.
The results indicated that microbial inoculation had significant effect (P