无壳葫芦根腐病病原菌的鉴定及生物学特性初步研究

Identification and preliminary studies on biological characteristics of the pathogen of shell gourd root-rot

近年来随着内蒙古无壳葫芦种植面积不断扩大,其病害也越来越严重,其中无壳葫芦根腐病是最普遍、最严重的一种病害。通过对无壳葫芦根腐病的病原菌进行分离、鉴定,确定该病原菌为茄镰孢(Fusarium solani)。本试验利用孢子悬滴法测量孢子萌发10 h后菌丝长度来研究病原菌的生物学特性,比较方便、省时、降低试验费用。该病菌在25℃条件下,菌丝生长速度最快,适应的pH范围较广,偏向于酸性;大型分生孢子萌发条件要求比较宽泛,小型分生孢子萌发条件要求较高,在PS培养液中萌发最好,土壤浸液能够促进分生孢子萌发以及菌丝生长;分生孢子的致死温度为60℃。

Shell gourd is one of the major crops in Bayannur City and the root-rot is the main disease in the grow- ing areas. Via isolation and identification, we confirmed that Fusarium solani （Mart.） Sacc. was the main patho- genic fungus for this disease. We firstly used conidium-drop method to detect the hyphal length at 10 hours after the spores germinated. In this way, we could analyze the biological characteristics of the pathogen more conven- iently and economically. Our results showed that the mycelia of this pathogen grew fastest at 25 ℃, were adapted to a wider range of pH values, and preferred acidity. Large-spore germination conditions were broad, while small conidia required stricter germination conditions, germinating the best in the PS medium, and soil extract could promote spore germination and mycelial growth; the lethal temperature to conidiospore was 60 ℃.