关键词: 拜赖青霉, 芝麻枯萎病, 生物学特性, 培养条件优化, 防治效果

Abstract: Penicillium bilaiae strain 47M-1 is a highly effective biocontrol strain with broad-spectrum inhibition activity and growth promotion ability, but its biological characteristics, optimum culture conditions and control efficacy on sesame diseases have not been systematically studied. The purpose of this study was to determine the biological characteristics, the optimum culture conditions and control efficacy of Penicillium bilaiae 47M-1. On the basis of identifying the biological characteristics of strain 47M-1, the optimum culture conditions of strain 47M-1 were obtained by single factor test with Fusarium oxysporum as target and the control efficacy was determined by pot test. The results showed that mycelium growth was fast under the conditions of 25 ℃～28 ℃, pH 5.0～7.0 and 0～16 h light in photoperiod, and sporulation was the high under the conditions of 25 ℃～28 ℃, pH 3.0～10.0 and 8 h light in photoperiod. Lethal temperature of conidia was 60 ℃ for minutes. The optimal culture fluid for producing inhibition substances was as follows: sucrose 30 g, yeast powder/beef extract/peptone 5 g, KCl 0.5 g, MgSO₄·7H₂O 0.5 g, FeSO₄·7H₂O 0.01 g, distilled water 1000 mL. When 2% or 3% spore suspension were inoculated with 75～125 mL optimized culture fluid at pH 7.0, and cultured at 25℃～27℃ for 5 days on a constant temperature shaker, the inhibition activity of culture filtrate was the strongest. The results of pot experiment showed that the control efficacy of both spore suspension and 10-fold diluent of fermentation filtrate were more than 70% against sesame Fusarium wilt. Penicillium bilaiae 47M-1 showed excellent potential for biocontrol. The results will lay a foundation for the study of inhibition substances, production of biocontrol agent and application in field.

Key words: Penicillium bilaiae, sesame Fusarium wilt, biological characteristics, optimization of culture conditions, control efficacy