Penicillium aculeatum PDR-4 and Trichoderma sp. PDR-16 promote phytoremediation of mine tailing soil and bioenergy production with sorghum-sudangrass

• PDR-4 and PDR-16 had As, Cu, Pb and Zn tolerance and plant growth-promoting traits.
• The fungi increased mobilization of P and heavy metals in mine tailing soil.
• Soil inoculation promoted growth and As, Pb and Zn uptake by sorghum-sudangrass.
• Co-inoculation was more effective than using single isolates.
• The fungi can promote phytoremediation and biomass production on mine tailing soil.

Fungi can facilitate phytoremediation of mine tailing soil containing heavy metal(loid)s (HMs). Penicillium aculeatum PDR-4 and Trichoderma sp. PDR-16, isolated from the rhizosphere of Pinus koraiensis in mine tailing soil, exhibited high HM tolerance and plant growth-promoting characteristics. The isolates increased available P in a 1:1 (w/w) mixture of soil and liquid media by 14–43% and the bioavailability of As, Cu, Pb and Zn was also increased. Both isolates exhibited phosphatase, phytase and siderophore activity. ACC deaminase activity was greater in PDR-16 than in PDR-4; IAA was produced by PDR-4 but not by PDR-16. Sorghum-sudangrass (Sorghum bicolor × sudanense) produced 37–95% more aboveground dry biomass and contained 74–128% more chlorophyll in inoculated soil. In soil inoculated with both isolates, HM concentrations increased in roots by 109% (As), 39% (Cu), 50% (Pb) and 38% (Zn), and in shoots by 72% (As), 69% (Pb) and 82% (Zn) compared to those of control plants (Cu concentration did not increase in shoots). HM bioavailability and available soil P, as well as plant biomass, chlorophyll content and plant As, Pb and Zn concentrations were highest in soil inoculated with both fungi. Results suggest that inoculating soil with P. aculeatum PDR-4 and Trichoderma sp. PDR-16 will be beneficial for phytoremediation and production of sorghum-sudangrass as a bioenergy crop in HM-contaminated soils.