Optimization of IAA Production by Halotolerant Bacterial and Fungal Consortia
Keywords:
Bacillus, CCD, Halotolerant, IAA, Placket BurmanAbstract
The current study focused on optimizing the production of indole-3-acetic acid (IAA) by halotolerant bacterial and fungal consortia, which are crucial for promoting plant growth under saline conditions. Initial screening using Plackett–Burman design identified pH, tryptophan concentration, and incubation period as the most significant factors affecting IAA synthesis. These factors were further optimized using Response Surface Methodology (RSM), resulting in maximal IAA yields of up to 125 µg/mL under conditions of pH 6.25–7.0, tryptophan 0.7–1.2 mg/mL, and incubation of 8.5–12 days. The statistical model exhibited strong significance (p<0.0001) with non-significant lack-of-fit, confirming the model's validity. The findings suggest that tailoring these parameters can significantly boost IAA production in halotolerant consortia, enhancing their potential as bioinoculants in saline-stressed soils. This work provides a solid foundation for developing effective microbial formulations to improve plant productivity in challenging environments.
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