پديد آورندگان :
موسوی، رقیه نويسنده دانشجوی دكتری گروه علوم خاك Mosavi, R. , سپهر، ابراهيم نويسنده دانشكده كشاورزي,گروه علوم خاك, دانشگاه اروميه,ايران , , صمدي، عباس نويسنده دانشكده كشاورزي- دانشگاه اروميه , , رسولی صدقیانی، میر حسن نويسنده دانشیار گروه علوم خاك Rasouli Sadaghiani, M.H. , صادق زاده، بهزاد نويسنده سازمان تحقیقات، آموزش و ترویج كشاورزی موسسه تحقیقات دیم كشور، مراغه Sadeghzade, B.
كليدواژه :
جو , ريزجانداران حل كننده فسفات , سنگ فسفات , فسفركارايي
چكيده لاتين :
Introduction: 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.
Materials and Methods: 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+F), RP inoculated with phosphate solubilizing bacteria (RP+B), RP inoculated with both fungi and bacteria inoculums (RP+B+F), 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.
Results and Discussion: The results indicated that microbial inoculation had significant effect (P <0.01) on grain yield, grain P concentration and Phosphorus efficiency, as on average TP increased from 9.5 g pot -1 in RP treatment to 16.4 g pot-1 in (RP+ B), to 22.8 g pot-1 in (RP+ F) and to 13.6 g pot -1 in (RP+B+F). PE increased from 0.49 in control to 0.74 in (RP+F), to 0.65 in (RP+B) and to 0.69 in (RP+B+F). There was significant difference between microbial treatments for PACE. It increased from 0.18 in control to 0.65 in (RP+F), to 0.47 in (RP+B) and to 0.40 in (RP+B+F). Compared with control treatment PACE increased by 2.5 times in (RP+ F), 1.6 times in (RP+ B) and 1.2 times in (RP+B+F). PUTE reduced significantly with increasing the P supply. On the average, the highest PUTE obtained in P0 treatment (0.55 g GDW/mg P) and reduced to 0.18 (g GDW/mg P) in (PS), to 0.31 (g GDW/mg P) in (RP +F), to 0.38 (g GDW/mg P) in (RP +B) and to 0.43 (g GDW/mg P) in (RP +B+F). There was no significant difference between P0 and RP treatments in PUTE. The barley genotypes showed significant differences (P <0.01) in yield parameters and P efficiency indices. In control treatment (P0), Obruk with 5.1 g pot-1 and Denmark with 2.5 g pot-1 had the highest and the lowest GDW; in microbial treatments, Sahand, Obruk, Gara-arpa and Rihane-03 had the highest TP. Rihane-03 and Diktoo had the highest PACE. Sahand and Abidar had the lowest PACE among the barley genotypes in control treatment (P0). In the (RP+F) treatment, PACE varied from 0.27 for Denmark to 2.23 for Obruk. In P0 treatment, Yea-168, Denmark and AltICB-98 were more efficient in P utilization and Dayton-Ranny, Obruk-68 and AltICB-98 were more efficient in P utilization than other genotypes in microbial treatments.
Conclusions: This study provides estimates of efficiency of different genotypes of barely. According to the results, Phosphate-solubilizing microorganisms were very effective to increasing the plant available P in soil as well as the growth and P efficiency of crops. Then, it was concluded that screening P-efficient varieties along with inoculation by phosphate-solubilizing microorganisms can be reduced application of the chemical fertilizers due to increasing P absorption from phosphate rock and insoluble forms of P in soil.
