Identification endophytic fungi of Nutgrass (Cyperus rotundus L.) as solubilizing phosphate and indole-3-acetic acid producers

Abstract

Low phosphate content in the soil can cause insufficient plant needs. Besides, the endophytic fungi of nutgrass have the potential as a phosphate solvent and can produce IAA (Indole-3-Acetic Acid). This study aimed to determine the levels of solubilizing phosphate and production of IAA (Indole-3-Acetic Acid) by the endophytic fungi of nutgrass and to identify the isolates based on rDNA-ITS sequences. The methods used were the isolation of endophytic fungi, analysis of solubilizing levels of phosphate and IAA production, and molecular analysis with rDNA-ITS sequences. Results of isolation and purification, found five isolates coded URT1, URT2, URT3, URT4, and URT5. The endophytic fungi of nutgrass were able to solubilizing phosphate levels around 54.03 - 87.83 ppm, with the highest levels produced by URT4 isolate. IAA levels around 5.58 - 45.50 ppm, with the highest levels produced by URT1 isolate. Based on molecular analysis with rDNA-ITS sequences, it showed that URT4 had 97.42% similarity to Aspergillus tereus species, while UTR1 had 100% similarity to Fusarium oxyporum species. To conclude, the endophytic fungi of nutgrass from A. tereus and F. oxyporum species have high levels of solubilizing phosphate and IAA production so that they are potential candidates for biofertilizer.