细辛叶枯病病原菌及其生物学研究

 研究确认细辛叶枯病病原菌为槭菌刺孢(Mycocentrospora acerina(Hartig) Deighton),是我国真菌新记录种。该菌分生孢子萌芽和菌丝生长的最适温度为15~20℃、最适pH7。分生孢子在清水中即可萌芽,条件适宜时0.5h即可产生芽突、5h萌芽率近100%。分生孢子致死温度接近50℃。田间病残叶上的分生孢子230天后仍具9%的萌芽率。新生菌丝在有光条件下可产生鲜艳的玫瑰红色素。该菌在供试的多种培养基上不能形成分生孢子,采用菌块切割、水滴保湿的方法可以诱生大量分生孢子。该菌对细辛有较强的致病性,在人工培养条件下可以产生毒素。

BIOLOGICAL CHARACTERISTICS OF THE PATHOGENIC FUNGI OF ASARUM LEAF BLIGHT

Asarum leaf blight caused by Mycocentrospora acerina (Hartig) Deighton is a wide-distributed and destructive disease in Northeastern China. The optimum temperature for conidium germination and hyphal growth of M. acerina is 15~20℃. The optimum pH value is 7. Conidia could germinate in water. Under proper conditions, conidia started germination in 0.5 hour and the germination percentage reach up to 100% in 5 hours. The lethal temperature for conidia was about 50℃. The conidia on the leaf spots could overwinter in the fields. Under light conditions, the hypha on PDA was able to produce rose-red pigment. The pathogen could not produce conidia on many kinds of media tested. By means of cutting the colony, keeping the humidity with water drops, the pathogen was able to produce a number of conidia. M. acerina could produce toxin in the media.