黑龙江省冬小麦雪腐病病原鉴定及生物学特性研究

Pathogen identification and biological characteristics of the winter wheat snow mold in Heilongjiang Province

采用形态特征观察和致病性测定方法,对黑龙江省饶河县冬小麦雪腐病进行了病原鉴定,并对病菌生物学特性进行了研究。结果表明,黑龙江省饶河县冬小麦雪腐病是由半知菌亚门雪腐格氏霉[Gerlachia nivalis(Ces.ex Sacc.)W.Gams et E.Mull.]侵染引起的红色雪腐病。病菌生长最适温度为20～25℃,适宜pH为7,但3.5～11.5范围内差异不显著;光暗交替有利于菌丝生长,最佳碳源为淀粉,最佳氮源为牛肉膏;病原菌致死温度为50℃处理10min。产孢最适温度为15℃,最适pH为7,最佳碳源为麦芽糖,最佳氮源为硝酸钠。缺N、C比缺Mg、Fe、K、P元素对病原菌的生长影响大。

The pathogen of the winter wheat snow mold in Heilongjiang Province was identified through morphological characteristics and pathogenicity. The results showed that winter wheat snow mold in Heilongjiang was pink snow mold, caused by Gerlachia nivalis （Ces. ex Sacc. ） W. Gams et E. Mull. Biological characteristics of G. nivale were also studied. The optimum temperature for mycelial growth was 20-25 ℃, and the suitable pH was around 7. Alternated light conditions benefited mycelial growth, and the best carbon and nitrogen sources were starch and beef extract, respectively. Lethal temperature of the pathogen is 50 ℃ （10 min）. The optimum condition for spore reproduction was 15 ℃ at pH= 7, and the suitable carbon and nitrogen sources were maltose and sodium nitrate, respectively. The lack of nitrogen and carbon influenced more severely on the pathogen growth than lack of magnesium, ferrum. kalium and phosphor.