A novel PGPF Penicillium olsonii isolated from the rhizosphere of Aeluropus littoralis promotes plant growth, enhances salt stress tolerance, and reduces chemical fertilizers inputs in hydroponic system

• DOI: 10.3389/fmicb.2022.996054
• Publication Date: 2022-10-27T13:07:38Z
• Authors: Mohamed Tarroum; Walid Ben Romdhane; Fahad Al-Qurainy; Ahmed Abdelrahim ...; Abdullah Al-Doss; Lotfi Fki; Afif Hassairi
• Keywords: Halotolerance; Dry weight

The hydroponic farming significantly enhances the yield and enables multiple cropping per year. These advantages can be improved by using plant growth-promoting fungi (PGPF) either under normal or stress conditions. In this study, fungal strain (A3) isolated from rhizosphere of halophyte Aeluropus littoralis was identified as Penicillium olsonii based on sequence homology its ITS region. A3 fungus shown to halotolerant (up 1 M NaCl) optimal growth at 27°C, but inhibited 40°C. liquid culture medium, produced indole acetic acid (IAA) especially in presence L-tryptophan. Tobacco plants grown system were used evaluate promoting activity direct effect mycelium (DE) indirect (IDE) cell-free filtrate (A3CFF). results showed that for two conditions (DE IDE) tobacco seedlings exhibited significant increase their height, leaf area, dry weight, total chlorophyll content. Interestingly, A3CFF (added MS medium nutrient solution (NS), prepared commercial fertilizers) induced parameters, proline concentration, catalase (CAT) superoxide dismutase (SOD) activities plants. maintained even after extended storage 4°C Since is a fungus, we tested ability alleviate salt effects. Indeed, when added 1:50 dilution factor NS 250 mM NaCl, enhanced tolerance increasing levels chlorophyll, proline, CAT, SOD activities. addition, treated accumulated less Na + roots more K leaves. also found induce expression five related genes (NtSOS1, NtNHX1, NtHKT1, NtSOD, NtCAT1). Finally, proved reduce half chemical fertilizers inputs. 0.5xNS supplemented with (1:50) higher than those 1xNS. an attempt explain mechanism, profile some (nitrogen metabolism (NR1, NRT1), auxin (TRYP1, YUCCA6-like), brassinosteroid (DET2, DWF4) biosynthesis) performed. all these up-regulated following treatment A3CFF. summary revealed P. stimulates growth, tolerance, reduces required fertilizer inputs system.