Regnier, TC, Mokgalaka, ND, Memel, O & Laing, MD 2011, 'Trichoderma harzianum as a tool for reaching suitable growth and vegetation cover on mine tailings', in AB Fourie, M Tibbett & A Beersing (eds), Mine Closure 2011: Proceedings of the Sixth International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 85-91, https://doi.org/10.36487/ACG_rep/1152_10_Regnier
(https://papers.acg.uwa.edu.au/p/1152_10_Regnier/)
Abstract: Rapid and efficient revegetation of mining landscapes is always a challenge. One of the main difficulties in revegetation is the amount of plants species which are able to establish and survive in the harsh conditions often associated with mining. Finding a suitable growth medium is the initial requirement for the plant to produce an appropriate vegetation cover. Fast growing plants with a good root system are of interest as they not only immobilise metals but also prevent erosion and soil compaction. For this reason, it is important for the phytoremediation biotechnologies to have a better understanding of the potential growth of different plant species.
Recent publications have shown the potential interest of using grasses as the first stage of revegetation. The candidates should be fast growing and resist metal toxicity when planted on mine tailings. Many products have been registered as growth promoters. One of them, Eco-T, a fungal species (Trichoderma harzianum Rifai strain kd) is currently produced in South Africa and well accepted as a growth promoter. AgriSil K50 a silica based product is known to provide a regular supply of potassium to the plant. 
The Department of Chemistry at Tshwane University of Technology has been assessing the efficacy of this growth promoter Trichoderma harzianum (Eco-T) in increasing the growth of some grasses while buffering the soil contaminated by copper and arsenic. Anthericum saundersiae was used as a model plant to confirm the effect of Eco-T on growth under stress conditions, thus providing preliminary data for further application. This study was extended to Sorghum (Sorghum bicolor (L) Moench) to evaluate its use as a phytoremediation candidate and as an alternative source of income from biofuel production. 
Initial results indicate that the combination of Eco-T and AgriSil K50 leads to a significant increase of the biomass, chlorophyll content in the presence of metals. This confirms that the application of this growth promoter in association with a chelating agent was able to reduce the toxic effect of the metals on the plants providing adequate stimulation of the root system and above ground biomass. In conclusion, this study highlights the importance of including growth promoters in the revegetation strategies.