甘肃省玉米鞘腐病病原菌鉴定及生物学特性观察

Dentification and Biological Characteristics of Pathogens of Sheath Rot of Maize in Gansu Province

2021年6月在甘肃省张掖市甘州区党寨镇自然感玉米鞘腐病的玉米植株中分离鉴定病原菌并观察分析病原菌的生物学特性。结果表明,该致病菌株(QF-1RC)形态学结构与拟轮枝镰孢菌(Fusarium verticillioides)一致。基于rDNA-ITS和微管蛋白序列分析发现,该病原菌与拟轮枝镰孢菌MN652651和FR997663的相似度达99%,结合形态学和与分子生物学的鉴定结果将其定为拟轮枝镰孢菌。生物学特性观察发现,菌丝生长最适温度为25℃,弱酸弱碱环境下均有利于菌丝生长,全光照环境条件下菌丝生长速率快,不同C、N源对菌丝生长和产孢量有一定的影响,D-纤维二糖培养基上菌丝生长相对受限,在海藻糖和D-半乳糖培养基上菌株产孢量较多,硫酸铵培养基上病原菌生长相对受限,乙酸铵培养基上菌株产孢量最多,硝酸钠培养基上菌株产孢量较少。

In June 2021,pathogens were isolated and identified from corn plants of naturally susceptible corn sheath rot in Dangzhai Town,Ganzhou District,Zhangye City,Gansu Province,and their biological characteristics were observed and analyzed.The results show that:The morphological structure of this pathogenic strain(QF-1RC)was consistent with that of F.verticillioides.Based on rDNA-ITS and tubulin sequence analysis,the similarity be⁃tween QF-1RC and F.Verticillioides(MN652651 and FR997663)reached 99%.Combined with morphological and molecular biological identification results,it was identified as F.verticillioides.It was found that the optimum tem⁃perature for mycelium growth was 25℃,The environment of weak acid and weak alkali was conducive to mycelium growth,The growth rate of mycelia was fast under full light,Different C and N sources had certain effects on myceli⁃al growth and spore production,The mycelial growth was relatively limited on D-cellose medium,while the spore production was more on trehalose and D-galactose medium.The growth of pathogenic bacteria was relatively limited on the(NH_(4))_(2)SO_(4) medium,the spore production of bacterial strains on the ammonium acetate medium was the most,while the spore production of bacterial strains on the NaNO_(3) medium was less.