紫胶霉病的初步研究 Ⅰ病原菌分离鉴定及其生物学特性

经鉴定,引起紫胶霉病的病原菌是芽枝状枝孢霉(Cladosporium cladosporioides)粉红单端孢霉(Trichothecium roseum)。浓色煤炱(Neocapnodium theae Hara)和柑桔煤炱(Capnodium Citri)主要为害寄主树,后期亦轻度为害紫胶。 芽枝状枝孢霉在PDA加蜜培养基上生长良好,菌落圆形,边缘整齐,表面菌丝茸毛状,鼠色,培养7—10天后,产生大量分生孢子。菌丝生长最适温为24—25℃,最适PH值5—6,孢子萌发最适相对湿度为96.1％。 浓色煤炱在PDA培养基上菌落圆形,边缘不整齐,浓黑色,后期中央部分产生絮状气生菌丝。培养5—8天形成大量分生孢子器,连续培养20天后,仍不形成子囊座。菌丝生长与分生孢子萌发的温、湿度,PH值与芽枝状枝孢霉相近。

A PRELIMINARY STUDY ON THE MILDEW SHELLAC ( LACCOFER CACER )I. Identification and biological characteristics of the causal organism of the mildew of shellac

The mildew of shellac has widely distriputed in the southern and northern Fujian province. The symptoms of disease, identification, and biological characteristics of the causal organism have been well studied.The causal organism of mildew of shellac ( cladosporium cladosporioides ) formed mouse colonies on Patato-Glucase Agar medium. After incubation for 7-10 days at 25℃, a great amount of conidia were produced. The optimum temperature of mycelia growth ranged from24℃to 26℃ and optimum PH was between 5-6. The high relative humidity was necessary for the germination of conidia.The causcal organism of host ( Neocapnodium theae ) formed black colonies on P. D. A medium. After Incubation for 5-7 days at 25℃, a great of pycnidia were produced and no ascus was formed after 20 dayS. The pycnidia and asci were produced under natural condition. The optimum temperature and the R. H, PH of mycelia growth were similar to those of Cladosporium cladosporioides.