桃枝枯病菌生物学特性研究

Biological characteristics of Phomopsis amygdali as pathogen of peach shoot blight

桃枝枯病是近年来在江、浙、沪一带出现的一种新病害,为有效防控桃枝枯病,对其病原桃拟茎点霉(Phomopsis amygdali)的生物学特性进行研究。结果表明:桃枝枯病菌菌丝在PDA培养基、温度25℃、pH 6.0~7.0及光照12 h·d^(-1)条件下生长最好;菌丝生长最适碳源是蔗糖和葡萄糖,最适氮源是蛋白胨和牛肉浸膏。病菌在PDA上易产生分生孢子器和分生孢子。分生孢子在温度25℃、pH 6.0~7.0、光照12 h·d^(-1)及高湿(95%以上)条件下萌发率最高。综合而言,不同的营养(培养基、碳源、氮源)、温度、光照、pH、湿度等环境条件对桃枝枯病菌菌丝生长和孢子萌发有显著影响。

Peach shoot blight is an occurring serious and new disease in Jiangsu,Zhejiang and Shanghai peach growing areas in recent years.The biological characteristics of Phomopsis amygdali of peach shoot blight was studied in order to provide the basis for further study and prevention of this disease.In this study,mycelial growth and conidial germination were detected in relation to temperature,illumination,pH,humidity and nutritional conditions.The results showed that the optimum temperature for mycelial growth of pathogen was 25 ℃,PDA was the best of the 4 culture media in the experiment,the befitting pH was 6.0 to 7,0,and 12 hours of illumination time each day was suitable for mycelial growth.The optimum carbon source of mycelial growth was sucrose and glucose,and nitrogen source was peptone and beef extract.PDA was the best for pycnidia and conidia production.The rate of conidial germination was highest under this condition which includes 25 ＂C,pH 6.0 — 7.0,12 hours of illumination time each day,and higher than 95%relative humidity.Therefore,different nutrients（media,carbon,nitrogen）,temperature,illumination,pH,humidity conditions have a significant impact on the peach shoot blight pathogen mycelial growth and conidial germination.