Selection of Ectomycorrhizal fungal strains for large scale inoculum production

Ectomycorrhizal (EM) fungal strains have been selected for large scale cultivation based on their tolerance ranges of temperature, pH and salinity. Among 60 EM fungal strains, 12 were observed to grow in the temperature range between 25 and 37 degrees C. Of these, 8 strains were able to grow in the pH range between 3 and 8. All 8 strains were capable of growing at 0.2% salt concentration, while 3 strains of Pisolithus tinctorius and one strain of Rhizopogon vulgaris survived upto 3% salt concentration. Temperature, pH as well as salinity affected sugar utilization and mycelial growth of EM fungi. Based on these studies, Laccaria laccata (3334), Pisolithus tinctorius (Pt M, Pt 144, Pt S237 and Pt 3339) and Rhizopogon vulgaris (S377) were selected. Further selection will be made based on their ability to vigorously form mycorrhizae in a wide range of tree species.