[Screening, identification of P-dissolving fungus P83 strain and its effects on phosphate solubilization and plant...

To isolate phosphate-solubilizing microorganisms from farmland, and to provide P-solubilizing microbial resource for bio-fertilizer production.

Phosphate-solubilizing fungus was identified using morphological and cultural characteristics and ITS rDNA sequence analysis. The phosphate-solubilizing capacity of strain P83 was measured by Petri dishes, broth medium and soil pot experiment. The effect of strain P83 on plant growth was studied in field trials.

Strain P83 was identified as Penicillium decumbens with a strong ability to dissolve insoluble phosphates. P83 dissolved 42.68% Ca3 (PO4) 2 (5 g/L) and the concentration of available phosphorus was 956 mg/L during a 10-d shaking incubation. The concentration of available phosphorus dissolved from Yonghe rock phosphate by P83 was 152.8 mg/L after 10d shaking incubation at 28 degrees C and a speed of 180r/min. P. decumbens P83 had a significant growth promotion effect on corn in Chao soil under three phosphates such as Ca3 (PO4) 2, Zn3 (PO4) 2 and rock phosphate. Compared with the control, inoculation with P83 increased the fresh weight of corn biomass by 9.5% - 89.2% and dry weight of corn biomass by 35% - 231%, and soil available phosphorus content increased 2.1 mg/kg -40.5 mg/ kg. Field trials show that P. decumbens P83 had a greater effect on enhancement of corn grain yield, the yield was average 9.2t/hm2 and 35.3% higher than the control.

One new phosphate- solubilizing strain P83 was obtained and identified as P. decumbens. It solubilized insoluble phosphates in petri dishes, broth medium and pot experiments. P. decumbens P83 could increase corn yield significantly in field trials. P. decumbens P83 strain has the potential for biofertilizer production in the future.