Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
Research Journal of Microbiology
Year: 2009  |  Volume: 4  |  Issue: 7  |  Page No.: 235 - 250

Rock Phosphate Solubilization by Two Isolates of Aspergillus niger and Penicillium sp. and their Promotion to Mung Bean Plants

W.I.A. Saber, K.M. Ghanem and M.S. El-Hersh    

Abstract: Isolation and identification of rock phosphate (RP) solubilizing fungi were studied under laboratory conditions. Fungal isolates that displayed the highest ratio of clear zone/colony diameter on plates of phosphate solubilization medium, were selected and identified as Aspergillus niger and Penicillium sp. The optimum condition for RP solubilization were found to be at the 6th (A. niger) and 7th (Penicillium sp.) day of incubation with shaking (150 rpm) at 30°C and pH ranging from 5.6 to 6.0. Glucose followed by fructose and xylose supported the RP solubilization process in the presence of 2.5 g L-1 RP as the optimum concentration. The overall soluble P after optimization studies on RP were 99.7 (A. niger) and 77.5 mg L-1 (Penicillium sp.). During the fermentation process, there was remarkable reduction in the final culture pH. The titratable acidity was positively correlated with RP solubilization. Under NaCl salt stress both fungi were able to solubilize RP, in which, A. niger was more tolerant than Penicillium sp. The dual and individual cultures of fungi solubilized sources of phosphate commonly exist in soil and also, possessed phytase activity. Under in vivo conditions, the inoculation of mung bean seeds with A. niger and/or Penicillium sp. in the presence of RP or calcium superphosphate (CSP), increased significantly the growth (except for branches No. plant-1), seed yield and P-uptake, as well as, improved the nodulation status and population of total and phosphate dissolving fungi in the rhizospheric soil of mung bean. These inoculations saved about 1/3 phosphate fertilizer dose. Hereby, these combined effects encourage the potential use of the isolated fungi in the biosolubilization of RP in soil plant system.

Cited References   |    Fulltext    |   Related Articles   |   Back
  Related Articles

Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility