林木病原菌广谱拮抗菌株的筛选及功能研究

以尖孢镰刀菌、腐皮镰孢菌、胶孢炭疽菌、拟盘多毛孢菌等林木常见病原菌为指示菌，用平板对峙法和菌丝球干重法，从土壤固氮细菌群中筛选广谱拮抗菌株，并调查了各菌株的溶磷及解钾能力。结果表明 对4 种病原菌拮抗能力较强的菌株有24 株，其中11 株能溶解无机磷，7 株能溶解有机磷，4 株有解钾功能。通过拮抗能力复筛得到最优菌株为菌株2024 和7014。菌种鉴定结果表明2024 菌株为枯草芽孢杆菌亚种( Bacillus subtilis subsp． subtilis) ，7014 菌株为成团
泛菌( Pantoea vagans).

Broad-spectrum antagonistic bacterial strains were screened from soil diazotrophic bacterial communities using common forest pathogenic fungi including *Fusarium oxysporum*, *Fusarium solani*, *Colletotrichum gloeosporioides*, and *Pestalotiopsis* spp. as indicator strains via the dual culture plate assay and mycelial ball dry weight method. Additionally, the phosphate-solubilizing and potassium-releasing capacities of all screened strains were evaluated. The results demonstrated that 24 strains displayed strong antagonistic activity against the four aforementioned pathogenic fungi. Of these, 11 strains could dissolve inorganic phosphorus, 7 strains could solubilize organic phosphorus, and 4 strains exhibited potassium-releasing functionality. Through secondary screening based on antagonistic performance, the optimal strains were identified as strain 2024 and strain 7014. Further strain identification results showed that strain 2024 was *Bacillus subtilis subsp. subtilis*, while strain 7014 was *Pantoea vagans*.