野燕麦生防菌株HZ-31的分离与致病性研究

Isolation and Pathogenicity of a Strain HZ-31 as a Biocontrol Agent for Avena fatua

为了开发恶性杂草野燕麦的生防真菌制剂,从刺儿菜患病植株根际经单孢分离获得一菌株HZ-31,并对其进行分离及致病性研究。结果表明,该菌株的适宜生长温度为20～30℃,喷雾接种病原菌的孢子量为1×108 mL-1时,接种后14d野燕麦地上部完全萎蔫,接种后保湿超过24h,可以明显提高该菌株的致病效果;在孢子悬浮液中添加φ=0.2%SDP可以明显提高致死效果,对小麦、蚕豆、豌豆安全,对青稞轻微致病,对油菜严重致病;形态学鉴定及ITS rDNA序列分析将其定为多孢木霉(Trichoderma polysporum)。综上,菌株HZ-31具有开发成为真菌除草剂的潜力。

To develop a biocontrol agent against the weed, Arena fatua L. （Wild oat）, a fungus strain HZ-31 was isolated from the infested weeds rhizosphere soil. Results showed that HZ-31 grows well at 20 ℃ to 30 ℃ When the inoculum concentration is 1×10^8 mL-1 ,wild oat could be killed within 14 days. When the dew period was more then 24 h, the virulence of HZ-31 could increase significantly. SDP with a concentration of 0.2% was proved to be the most efficacious adjuvant to HZ-31. Strain HZ-31 kept perfect security to crops such as wheat, broad bean and pea and had light or severely susceptible to barley and rape. According to morphology and ITS rDNA analysis, the strain HZ-31 was identified as Trichoderma polysporum. Therefore, the fungus strain HZ-31 may be with the potential of being exploited as a mycoherbicide.