<i>Preussia</i> sp. BSL-10 producing nitric oxide, gibberellins, and indole acetic acid and improving rice plant growth

<i>Preussia</i> sp. have been least known to improve plant growth and produce phytohormones. The current study investigated the production of nitric oxide (NO), indole-3-acetic acid (IAA), and gibberellins (GA₄, GA₇, GA₁₅, and GA₅₃) by a novel endophytic-fungal strain <i>Preussia</i> sp<i>.</i> BSL-10 using advanced chromatographic and spectroscopic techniques. Production of these phytohormones were validated by RT–PCR analysis, which indicated the expression of genes encoding <i>tryptophan synthase</i> (<i>TRP</i>), <i>indole-3-acetamide hydrolase (IAAH), tryptophan-2-monooxygenase (IAAM), aldehyde dehydrogenase (ALD), GA₄ desaturase (DES), geranylgeranyl-diphosphate synthase (GGS2), ent-desaturase oxidase (P450-4), GA₁₄ synthase (P450-1) and nitrite reductase (NIRK/NIRS), cytochrome P450 (P450nor), nitrate reductase (NR), NOS-like (NOL),</i> and <i>nitric oxide reductase (QNOR/CNOR).</i> In plant growth-promoting effects, the inoculation of <i>Preussia</i> sp. BSL-10 significantly increased the growth of dwarf mutant <i>Waito-C</i> and wild-type rice cultivars. In conclusion, utilizing new endophytic with the ability to produce NO, IAA, and gibberellins can be used to promote growth and yield of marginalized crops.