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bioRxiv · 10.64898/2026.10.21.760685

Study on The Effect of a Propiconazole Based Fungicide on Plant Growth Promoting Properties of Isolates from Wheat Rhizosphere

Haque, M. T.·Saha, A.·Begum, A.·Akhter, H.
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Abstract

Reliance on propiconazole based fungicides has been on the rise for better harvest of crops. Such fungicides can also affect non-target rhizosphere microorganisms. However, the off-target effect of propiconazole on rhizobacteria remains scarcely discussed. The main objective of the present study was to observe the effect of this compound on six plant growth promoting (PGP) properties of wheat rhizosphere isolates using a statistical approach. The study showed that although the overall PGP profile shifted only modestly across propiconazole doses, siderophore and ammonia production were suppressed at the highest fungicide concentration, IAA production declined in the presence of the fungicide, and cellulase activity declined at 4.24 mg/L and above, whereas siderophore appeared to act as a bridge between growth promotion and enzymatic activity. This pattern indicates propiconazole exerts a selective pressure on specific traits rather than holistic disruption. The findings of this study contribute to our understanding of pesticide risk assessment in sustainable agriculture.

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Haque, M. T., Saha, A., Begum, A., Akhter, H.. 2026-10-22. Study on The Effect of a Propiconazole Based Fungicide on Plant Growth Promoting Properties of Isolates from Wheat Rhizosphere. https://doi.org/10.64898/2026.10.21.760685

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