苹果斑点落叶病菌的生物学特性

苹果斑点落叶病菌是ＡｌｔｅｒｎａｒｉａｍａｉｌＲｏｂｅｒｔｓ的强毒株系，该菌生长发育温度范围是５～３５°Ｃ，最适温度为２８℃。在ｐＨ３～９之间的培养基上生长良好，但以４．５～６．０为最佳。各光照处理对菌落的形成差异较明显，以黑暗与日光灯交替处理病原茵生长最快。该茵在ＰＳＡ、ＰＤＡ培养基上生长速度快，且产孢呈大。病原菌能有效地利用碳源，以萄葡糖最佳，蔗糖次之。氮源以牛肉胨最好，尿素最差，分生孢子萌发温度范围在５～３５℃，最适萌发温度为２５℃。在湿度试验中，当相对湿度高于８５％时，孢子萌发率逐渐提高。该菌孢子致死温度为５５℃。

Studies on the Biological Characteristics of Alternaria mali Roberts

The biological characteristics of Alternaria mali Roberts(the pathogen of appleleaf spotted disease)were tested in Gansu from 1990～1994.The results revealed that thetemperatures for the growth and development of this pathogen were 5～35℃,with the opti-mum of 28℃,the pH values from 3 to 9,with the optimum of 4.5～6.0 for the mycelialgrowth.The alternation of darkness and fluorescent light treatments favored the pathogendeveloping.The best media for the fungi growth and sporulation were PDA. The fungi grewbetter in glucose and sucrose as the carbon sotirce. Among nitrogen sources,beef extract wasthe best,urea was the worst.The optimum temperature of spore germination was 25℃.Therelative humidity for spore germination was above 85%. The lethal temperature of thepathogen was 55℃.