Abstract:

Using traditional taxonomic methods, ITS sequences and phylogenetic analysis, Trichoderma strain NTYM-0112 isolated from an Antarctic moss habitat was identified as T. asperellum. A preliminary study was made of its antibacterial activities and range in inducing salt and cold resistance effects in plants. The antibacterial activities results revealed that strain NTYM-0112 showed obvious inhibition to seven common plant pathogens including Pyrfcularia oryzae, Verticillium dahlia and Fusarium graminearum. Salt resistance results indicated that the germination rate of tomato seeds increased 13.4% compared with the control after treatment with strain NTYM-0112; the salt injury index reduced significantly by 35.7%; and the survival rate and water content of tomato dry weight increased by 34.4% and 20.4%, respectively, after treatment with strain NTYM-0112. The MDA content of leaves was obviously reduced compared with the control. The cold resistance results showed that after treatment with strain NTYM-0112, the electrolyte leakage rate of cucumber seedlings at 0°C, 5°C and 10°C reduced by 13.1%, 20.9% and 32.8%, respectively, and the extravasation values of soluble sugar decreased by 18.0 mg/g, 28.6 mg/g and 48.4 mg/g, respectively. All of these results confirmed Antarctic habitat strain Trichoderma asperellum possessed preferable antibacterial activity and effect of inducing plant resistance to stress.

Key words: cold resistance