Acid and alkaline phosphatase enzyme activities of different strains of soil fungi in the presence of organic compounds of phosphorus (phytic acid and sodium glycerophosphate)

Document Type : Research Paper

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Abstract

Soil fungi play an important role in nutrient cycling. They have a significant effect on mineralization of organic matter in soils. Some fungi could decompose organic compound with producing different enzymes. Since soil phosphorus in organic soils exists mostly in organic forms, fungi have a vital role in mineralization of those compounds. In order to study the effect of phytic acid and sodium glycerophosphate on acid and alkaline phosphatase activities  of some fungi isolates, an experiment was conducted as a completely randomized design with factorial arrangement with three replications. The first factor included seven fungi isolates (four Aspergillus isolates(A19,A15,A10,A7) and three fungi isolates (Penicillium, Rhizoctonia Solani Trichoderma harzianum) and control (no fungus)) and the second factor included two different organic phosphorus compounds (Phytic acid and Sodium Glycerophosphate). All isolates were grown in PDB at 28 oC and acid and alkaline extracellular phosphatase activities were determined after 7 and 14 days inoculation. The results showed that acid and alkaline phosphatase activity was significantly different among all soil isolates on a 5% significance level. The highest level of acid and alkaline extracellular phosphatase was observed in Trichoderma harzianum (Th) treatment. In this experiment, A15 was the superior among Aspergillus Isolates. Different studies showed that acid phosphatase activity was higher than alkaline extracellular phosphatase among all studied isolates and type of organic phosphorus compound had a significant effect on the phosphatase enzyme activity among all studied isolates. Acid and alkaline Phosphatase activity in sodium glycerophosphate treatment was higher than phytic acid.