Abstract: By the methods of laboratory incubation and bioassay, a simulation test was conducted to study the allelopathic effects of different concentration diisobutyl adipate on pepper seed germination and its seedling growth and Fusarium oxysporum f. sp. vasinfectum. For the pepper seed germination and seedling growth, diisobutyl adipate exhibited allelopathic promotion at low concentration, but allelopathic inhibition at high concentration. There existed greater differences in the allelopathic effects of diisobutyl adipate on the seed germination and seedling growth of pepper and eggplant. The promotion effects of low concentration diisobutyl adipate on pepper were stronger than those on eggplant, while the inhibition effects of high concentration diisobutyl adipate on pepper were weaker than those on eggplant. All test concentration diisobutyl adipate had significant inhibition effects on the mycelium growth of Fusarium oxysporum f. sp. vasinfectum, and the effects increased with increasing diisobutyl adipate concentration, being the strongest (an inhibitory rate of 10.75%) at 1 mnol·L^-1. Field text indicated that diisobutyl adipate at all test concentrations enhanced the disease resistance of pepper seedlings. The best effect was observed at 1 mmol·L^-1 of diisobutyl adipate, with the disease index decreased by 49.88%, compared to the control.

Key words: Subalpine coniferous forest, Ecological process, Artificial restoration, Species diversity, Picea asperata