温度、湿度和光照对苹果炭疽叶枯病菌(Glomerella cingulata)产孢的影响

苹果炭疽叶枯病(Glomerella cingulata)是我国苹果上新发现的一种病害,为了了解病原菌的产孢条件和产孢动态,为病害的预测预报与防控提供依据。本研究在人工控制条件下,测试了温度、湿度和光照对苹果炭疽叶枯病菌产生分生孢子和子囊孢子的影响。结果表明,苹果炭疽叶枯病新形成的病叶润湿后,在15℃~30℃下保湿培养2~6 d后可产生大量橘黄色的分生孢子堆,其中30℃下产孢量最大,产孢速度最快,仅需2 d时间。炭疽叶枯病菌在新形成的病叶上于15℃~30℃下培养20~30 d可形成子囊孢子,最适温度为25℃,子囊孢子的形成需要高湿环境或叶片润湿。炭疽叶枯病菌的单孢分离菌株于15℃~25℃下,在马铃薯葡萄糖琼脂培养基(PDA)上培养20~30 d也可形成子囊孢子,最适产孢温度25℃。紫外光、黑光和日光都能促进子囊孢子的形成。

Effect of temperature,moisture and illumination on sporulation by Glomerella cingulata

Glomerella leaf spot (GLP) caused by Glomerella cingulata is a new kind of apple disease in China. To understand the requirements and developments of sporulation by the pathogen, and provide information for developing methods to forecast and control the disease, effect of temperature, moisture and illumination on sporulation of conidia and ascospores were investigated under artificially controlled environment. Results showed that when wetted disease leaves were cultivated in the environment at 15℃-30℃ with RH=100% for 2-6 days, a large amount of acervuli and conidia were produced on diseased leaves. The largest amount of conidia was observed at 30℃ among all the temperature treatments and only 2 days were required for conidial formation. Perithecia and ascospores were also produced on the diseased leaves when cultured at 15℃ to 30℃ for 20-30 days. The optimum temperature for G. cingulate to produce perithecia was 25℃ and formation of perithecia required saturated relative humidity or wetted environment. Perithecia and ascospores were also produced by the single-spore isolates of G. cingulata after cultivated on PDA at the optimum temperature (25℃) for 20-30 days. Result also showed that UV light (254 nm), black light (365 nm) and sunlight can promote the sporulation of the pathogen.