Effect of Piriformospora indica and Trichoderma tomentosum fungi on basil (Ocimum basilicum L.) growth under copper nitrate levels

In order to investigate the effects of Piriformospora indica and Trichoderma tomentosum fungi on basil (Ocimum basilicum L.) growth under copper nitrate levels, a pot experiment in factorial arrangement with three replicates was done during 2012. Treatments were four levels of copper nitrate (0, 100, 200 and 300 mg kg-1 of soil) and four levels of fungal coexistence (non-inoculation control, inoculation of Piriformospora indica and Trichoderma tomentosum fungi alone and co-inoculation of two fungi). The seeds were inoculated at before planting time and copper nitrate was fertigated four weeks after planting. The studied parameters were plant height, stem diameter, branches number, leaf number per plant, both stem and leaf fresh and dry weights. Results indicated that all measured parameters except leaf fresh weight showed a positive response to copper nitrate concentrations. In terms of plant height and dry weight of leaf and stem a quadratic equation while for other traits a linear equation was fitted. Interaction between copper nitrate and fungi inoculation was significant for branch number, leaf number, leaf, stem and plant fresh weights and plant and leaf dry weights. Coinoculation of two fungi had the most positive effect (ranged from 14 to 50%) on the mentioned traits. In conclusion, results of the present study represented a positive effect of copper nitrate, mycorrhizae-like fungi and Trichoderma especially for simultaneous application of two fungi along with copper nitrate on basil growth and yield improvement.