2023 Volume 60 Pages 15-23
The preservation of four strains of Trichoderma spp. using mycelium agar disks (5 mm in diameter) soaked in four kinds of cryoprotectants (i.e. 40% (w/w) maltose aqueous solution, 40% (w/w) glucose one, 10% (w/w) glycerol one, and pure water) at 20°C of an experimental freezer and at around 19°C of a domestic freezer was investigated. The results obtained were as follows:
(1) The survival rate of the four strains (NBRC 33016, 93130Tr, ANCT-05011, ANCT-05138) was 100% soaked in the maltose aqueous solution, the glucose one, and the glycerol one at -20°C for 133 days.
(2) Using the maltose aqueous solution for the cryoprotectant, the survival rate of all two strains tested (NBRC 33016, ANCT-05011) was 100% at 20°C and at around -19°C for 240 days.
(3) Using pure water for the cryoprotectant, the survival rate of the two strains tested (NBRC 33016, ANCT-05011) was 100% at -20°C and at around -19°C for 84 days. Therefore, it was revealed that the cryopreserving of Trichoderma spp. strains using mycelium agar disks at around -20°C had a potential.