Mycoremediation of Cd and Pb from contaminated soil using arbuscular mycorrhiza Glomus leptotichum

The objective of study was to investigate the possibility of utilization of arbucular mycorrhizae (AM) to clean up the soil contaminated with two heavy metals, Cd and Pb using sunflower plants ( Helianthus annuus ) as a test plants. AM fungi used was Glomus leptotichum. Study was carried out under controlled conditions and sterilized soil. There was significant increase in dry weight of the root system of the AM inoculated plants compared to the negative control. The results showed variable effect of heavy metals on the dry weight of shoot system. Root and shoot dry weight, in response to increasing concentrations of heavy metals applied to the soil, had a significant adverse or negative effect of Cd and non significant effect at the concentration 50 and 100 ppm of Pb on plants inoculated with AM fungi. The AM showed high efficiency for extraction of these heavy metals from the soil at low concentrations and reduction of this efficiency at high concentrations. Compared to shoot rate of accumulation was almost five times lower than the roots. The rate of Cd accumulation in the seeds of the plant was within the toxic levels and recorded 12.9 ppm. in the plants inoculated with G. eptotichum. This indicates the efficiency of thisAM species to remove this metal from the soil, i.e. within the toxic levels and probably present a risk to human health.