Phytotoxicity Test to Check the Effectiveness of Mycoremediation to Support Seed Germination and Plant Growth in Withania somnifera (L.) Dunal

In the present study, the effect of different treatments on the growth parameters of Withania somnifera (L.) Dunal was evaluated. Soil samples were collected from the oil spill site by stratified random sampling method, i.e. near the well (NW), 20 metre distance, 40 metre distance, 60 metre distance and 80 metre distance from the oil spill well. Eight different treatments were applied to crude oil contaminated soil samples from five different distances. The treated soil samples were incubated for 14 days, and transferred to root trainers in a glass house and then the seeds of Withania somnifera (L.) Dunal were sown. It was kept for four months under a glass house and net house conditions. Growth parameters like collar diameter, shoot height, root length, fresh weight, dry weight and percentage germination of plants were measured in each treatment. Two-way analysis of variance was carried out to study the effect of treatments, distances and their interaction on growth parameters of Withania somnifera (L.) Dunal. Best values of the plant parameters (like collar diameter = 2.21 mm; shoot height = 3.200 cm; root length = 12.6 cm; fresh weight = 0.526 g; dry weight = 0.132 g) were obtained when the soil was sterilised and bioaugmented with yeast extract, molasses and Aspergillus terreus.