两种橡胶炭疽病菌生物学特性的比较

Biological characteristics of 2 species of Colletotrichum causing Colletotrichum leaf disease

胶孢炭疽菌（Colletotrichum gloeosporioides Penz．）和尖孢炭疽菌（ColletotrichumacutatumSimmonds）均能引起橡胶炭疽病的发生，胶孢炭疽菌是主要病原。通过对2种橡胶炭疽病菌的生物学特性进行研究，结果表明：胶孢炭疽和尖孢炭疽的最适温度均为28℃。胶孢炭疽在全光照的条件下，菌落直径最大；而尖孢炭疽在光暗交替的环境下，菌丝生长最好。2种炭疽菌生长的适宜pH值均为6～8。它们对碳源的利用有较大差异，胶孢炭疽在麦芽糖上生长最好，而尖孢炭疽在甘露醇和乳糖上生长较好。2种炭疽菌对甲基托布津的敏感性差异显著，尖孢炭疽有较强的耐药性。

Colletotrichum leaf disease was caused by Colletotrichum gloeosporioides Penz. and Colletotrichum acutatum Simmonds. Colletotrichum gloeosporioides Penz. was the major pathogen. The biological characters of Colletotrichum gloeosporloides and CoUetotrichum acutatum was reported in this paper. The result showed that the optimum temperature of mycelium growth was 28 ℃ for CoUetotrichum gloeosporioides and Colletotrichum acutatum. The mycelium growth of Colletotrichum gloeosporloides was the best under light. However, the alternation of light and darkness every 12 hours was found to be the best for Colletotrichum acutatum. The optimum pH range of mycelium was pH 6 -8. There were significant differences on the carbon resources between Colletotrlchum gloeosporioides and Colletotrichum acutatum. Colletotrichum gloeosporioides grew well on the media using maltose as the carbon resources and Colletotrichum acutatum grew well on mannitol and lactose. There was obsot obviously differente of the reaction of Colletotrichum gloeosporloides and Colletotrichum acutatum to 70 % thiophanate-methyl, Colletotrichum acutatum had stronger resistance to fungicide.