Abstract: In order to study the effect of Trichoderma asperellum ACCC30536 on the physical and chemical properties and nutrient components of the soil in a 60-day growing period under field conditions, we conducted pot culturing experiment of one-year-old tissue-cultured Populus davidiana×P.bolleana seedlings. Both soil in empty pots and soil in seedling-culturing pots were treated with T.asperellum conidia solution at the concentration of 5×10³ cfu·cm^-3 soil in the experiment (as T and T1 group), where bare pot soil and soil in a seedling-culturing pot without treatment were taken as control groups (Con and Con1, respectively). By ANOVA, the differences in inducing durations and levels of T.asperellum treatment significantly influenced the moisture content of the soil (P<0.05), while all treatments significantly decreased the moisture content (P<0.05). The differences in inducing durations and levels of T.asperellum treatment had no significant influence on the alteration of soil pH (P>0.05). Although T.asperellum treatment had a general buffering effect on soil pH, the pH was kept in the range of 6.84-6.97. The differences in inducing durations and levels of T.asperellum treatment significantly affected the content of organic matter, total nitrogen, total phosphorus, available phosphorus and total potassium (P<0.05), resulting in a highest organic matter content of 1.27 and 1.31 times of that of Con and Con1 respectively, among those of all sampling time points in all seedlingculturing pots (P<0.05), and a maximum total nitrogen content of 1.18, 1.18 and 1.25 times of those of Con, Con1 and T, separately (P<0.05), and a maximum total phosphorus content of 1.12 times of that of Con1(P<0.05), a maximum available phosphorus content of 1.13 times of that of Con1 (P<0.05), and a maximum total potassium content of 1.17 times of that of Con1 (P<0.05). Inducing duration had a significant influence on the available potassium content (P<0.05), while difference in treatment levels had no significant influence on the available potassium content of the soil (P>0.05). Furthermore, the interaction between the inducing durations and the difference in treatment levels of T.asperellum also significantly influenced the above indexes (P<0.05). Therefore, T.asperellum ACCC30536 conidia treatment can significantly affect the physical and chemical properties and the nutrient components of soil.

Key words: Trichoderma asperellum, Populus davidiana×, P.bolleana, soil nutrient, soil moisture content, soil Ph