Total 69 isolates of Phytophthora nicotianae var. nicotianae were isolated and identified from tobacco black shank samples collected from different areas of Anhui province,and mating types of the oomycete were investi...Total 69 isolates of Phytophthora nicotianae var. nicotianae were isolated and identified from tobacco black shank samples collected from different areas of Anhui province,and mating types of the oomycete were investigated by the method of partnership culture in vitro on L-tryptophan medium with β-sitosterol.The results showed that A2 mating type was the predominant in isolates of P.nicotianae var.nicotianae,next was A0 mating type,A1 and other mating types were not observed.It was suggested that sexual reproduction of P.nicotianae var.nicotianae might not take place frequently,and Anhui province might not be the original center of P.nicotianae var.nicotianae.The results indicated further that mating type geographical distribution of P.nicotianae var.nicotianae in Anhui province was in line with that in China.In addition,the significance of the test results and the possible reason for A1 mating type being absent were discussed.展开更多
文摘Total 69 isolates of Phytophthora nicotianae var. nicotianae were isolated and identified from tobacco black shank samples collected from different areas of Anhui province,and mating types of the oomycete were investigated by the method of partnership culture in vitro on L-tryptophan medium with β-sitosterol.The results showed that A2 mating type was the predominant in isolates of P.nicotianae var.nicotianae,next was A0 mating type,A1 and other mating types were not observed.It was suggested that sexual reproduction of P.nicotianae var.nicotianae might not take place frequently,and Anhui province might not be the original center of P.nicotianae var.nicotianae.The results indicated further that mating type geographical distribution of P.nicotianae var.nicotianae in Anhui province was in line with that in China.In addition,the significance of the test results and the possible reason for A1 mating type being absent were discussed.
文摘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15 d.
