云南小叶黄杨叶斑病病原鉴定及生物学特性分析

Identification and Biological Characteristics of Pathogen Causing Buxus microphylla Leaf Spot,Yunnan

文章对小叶黄杨叶斑病病原进行形态鉴定及ITS和TUB2序列分析,并在不同温度、p H值、光照周期、碳源、氮源等条件下的生长及孢子萌发状况进行了较为系统的研究,测定了不同杀菌剂对病菌的抑菌效果,为该病害防治提供理论依据。实验结果表明,该菌为拟盘多毛孢属Pestalotiopsis sp.,其适宜的生长温度范围为25~30℃。不同光照条件处理下的菌落生长无明显差异,光照有利于孢子萌发,NO-3态氮的利用最有利于菌落生长,而在不同碳源条件下,其菌落生长无明显差异。分生孢子萌发的最适p H值为8,抑菌效果最好的是百菌清。

The morphological identification and ITS and TUB2 sequences systematical analysis of the pathogen was given in this paper,and the influence of various temperature, pH value, photoperiod, different carbon and nitrogen source, fungicide on the growth and conldlo- phores gemtination of a fungi isolate from Buxus microphylla were studied. The results showed that the fungal belonged to the genus of Pestalotiopsis sp. , 25 - 30℃ was the optimum temperature for colony growth and conldiophoree germination. Different illumination had no obvi- ously influences on isolate growth,but illumination was beneficial for conidiophores germination of Pestalotiopsis strain. NO3^- was the opti- mum sole nitrogen source to the strain growth, while there were no significant effects on the strain gnnvth with different carbon source. The optimum pH value for conidiophores germination was 8. Chlorothalonil had the most antlfungal effect on this strain.