利用麦瓶草病原菌株WP-1开发微生物除草剂初探

从自然感病的麦瓶草近基部分离得到一寄生疫霉菌株(WP-1),土壤接种盆栽试验结果表明,在供试的作物和杂草范围内,该菌的寄主范围相对专一,感病植物主要集中在十字花科、苋科和石竹科;无菌培养滤液强烈抑制麦瓶草幼苗胚根生长,抑制率为86.1%;该生防菌及其代谢产物具有开发微生物除草剂的潜力。对该菌的生物学特性研究表明:菌丝菌落生长的最佳条件为番茄培养基(液),20~28℃,光照,震荡增大通气量有利于菌丝体生长。偏碱性有利于生防菌菌落的生长,但液体培养环境下对培养基的初始酸碱度要求不严格;培养滤液对植物毒性最强的培养条件为Plich’S培养液和马铃薯葡萄糖培养基液PDB,25~30℃,中性偏酸,黑暗,静止培养15d。

Preliminary Results of the study on Phytophtoora nicotianae (WP-1) as a Mycoherbicide

An indigenous strain of Phytophtoora nicotianae (WP-1) was isolated from infected Conical Silene stems in Taian, Shandong, P. R. China, in 2003. Its host range and biological characteristic was investigated. The result of host range tested with 37 plant species showed that the pathogen was safe except for several plant species of Caryophyllance, Achyranthes and Cruciferae. The result of bioassay showed that the crude of filtrate from the strain is toxic to Silene conoidea L. For mycelium growth, the optimal culture condition was TA media in solid, CFB media in liquid, independent on the tissue juice of Silene conoidea L; 20~28℃; pH 4 ~9; 24 hours light every day ; shaking culture 15 days. The filtrate of WP–1 cultured in Plich’S media at 28℃, dark, still, acid for 15 days was phytotoxic to Silene conoidea L. Although the filtrate doesn’t inhibit the germination of seeds of Silene conoidea L., it could significantly restrain the growth of the root. The experimental results will assist in further developing mycoherbicide and utilizing the phytotoxin of the strain WP-1 to develop bioherbicide.