Synergistic association of endophytic fungi enhances tolerance, growth, and heavy metal uptake of Alocasia calidora in landfill contaminated soil

The present research is designed to determine the influence of inoculation of a consortium of indigenous filamentous fungi on the modulation of Alocasia calidora growth attributes and biochemical responses and to investigate the tolerance, uptake, and translocation of multiple metals under multi-metal contamination. The results revealed increased activity of soil enzymes: urease (EC 3.5.1.5), acid phosphatase (EC 3.1.3.2), invertase (EC 3.2.1.26), and dehydrogenase in the fungi supplemented soil. The inoculation of A. calidora with a consortium of fungi enhanced substantially the shoots and roots growth through improved production of chlorophyll and carotenoids. The upregulated activity of antioxidant enzymes (peroxidase (EC 1.11.1.7), catalase (EC 1.11.1.6), and ascorbate peroxidase (EC 1.11.1.11)) was equally monitored in the fungi inoculated A. calidora. Various metabolites which aided the metal tolerance, growth, and accumulation were determined in the plant (Tryptophan (L-tryptophan), Indole-acrylic acid (Indole-3-acrylic acid), 5,7,2',3'-Tetrahydroxyflavone, 5,2-Dihydroxyflavone, Scutellarein-6-glucoside, tripeptides, S-(4-Nitrobenzyl) glutathione). Chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were significantly accumulated in the shoots of inoculated A. calidora (P < 0.05), while, the accumulated iron (Fe, 1203.00 mg/kg), Pb (347.51 mg/kg), and Zn (523.02 mg/kg) in the roots of inoculated A. calidora were also higher than those of the control A. calidora. It is presumed that inoculation of A. calidora with fungal organisms can be utilized as an effective strategy for enhancing the tolerance, growth, and metal removal from polluted soils.