Biosynthesis of Plant Growth Hormones (Indol Acetic Acid and Gibberellin) By Salt-Tolerant Endophytic Fungus Aspergillus terreus SQU14026

Ghoniemy, Eglal A.; El-Khawaga, Maie A.; Abd El-Aziz, Marwa A.; Abulila, Hend I.

doi:10.21608/eajbsg.2020.214043

Biosynthesis of Plant Growth Hormones (Indol Acetic Acid and Gibberellin) By Salt-Tolerant Endophytic Fungus Aspergillus terreus SQU14026

Document Type : Original Article

Authors

¹ Department of Botany and Microbiology, Faculty of Science, Al-Azhar University (Girls Branch), Cairo, Egypt.

² Regional Center for Mycology and Biotechnology, Al-Azhar University, Cairo, Egypt

10.21608/eajbsg.2020.214043

Abstract

Twenty-seven fungal isolates were isolated from salt-tolerant (halophytes) plants, which were collected randomly from the planted field in Wadi El-Natroun. All isolates screened for production of plant growth hormones (GA and IAA) production and salt tolerance. All isolates can tolerate salts and produce GA and IAA in varying degrees. The maximum IAA and GA production were obtained by isolating 19 (0.098 and 0.77 µg mlˉ¹ respectively), which can tolerate salts (NaCl) up to 15% with MSC 20 mglˉ¹. According to DNA and PCR amplification, isolate 19 was identified as Aspergillus terreus strain SQU14026. The optimum culture conditions for a maximum of production growth hormones by Aspergillus terreusstrain SQU14026 were studied. The maximum yield was obtained on the 8^th day of incubation at incubation temperature 30^oC and pH6 on Czapeks Dox medium containing 10% NaCl, using glucose and ammonium sulphate concentrations (20g and 3g respectively). The high level of IAA and GA production attained by adding 0.2 mg / ml tryptophan to the growth medium under controlled conditions, the production increased by 124.7% and 48.19% respectively compared to their production at 8^th day.

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