烟草赤星病菌(Alternaria alternata)营养生理研究

研究了6种碳源和6种氮源对烟草赤星病菌Alternaria alternata(Fr)Keissler]菌丝生长和产孢量的影响。结果表明,不同的碳源和氮源对该病菌菌丝生长和产孢量均有显著影响。病菌在以淀粉为碳源的培养基上菌丝生长最快,乳糖次之;菌丝干重以果糖培养基上最大,乳糖、葡萄糖、麦芽糖、蔗糖、淀粉次之,无碳对照最低;产孢量以在麦芽糖为碳源的培养基上最高,乳糖次之,无碳对照最低。病菌在以蛋白胨为氮源的培养基上菌丝生长最快,菌丝干重最大,硝酸铵次之,脲最慢;产孢量以在蛋白胨为氮源的培养基上最高,硝酸铵、硫酸铵上次之,脲最低。脲和氯化铵对病菌生长和孢子形成均有抑制作用。

Studies on Nutritional Physiology of Alternaria alternata

The effects of different carbon and nitrogen sources on Alternaria alternata (Fr) Keissler, the causal organism of tobacco brown spot were studied in this paper to probe the nutrition requirement for mycelial growth and conidial production and provide experimental evidence for studying the pathogenic mechanism and framing control countermeasure. The results showed that the mycelium growth and conidial production of the fungus were largely influenced by different carbon and nitrogen sources. The pathogenic fungus could make good use of the carbon sources tested. Soluble starch was the best carbon source for the mycelium growth of the fungus, next was lactose. Fructose was the best carbon source for the increase of the dry weight of mycelium, the next were lactose, glucose, maltose, sucrose and soluble starch in turn, and carbon-free CK was the least. Maltose was the best carbon source for conidial production, the next was lactose. The fungus could also utilize the nitrogen sources tested. Among the 6 tested nitrogen sources, peptone was the best for the mycelium growth and sporulation, the next was ammonium nitrate, and urea was the worst. But there were little spores and the dry weight of mycelium in the medium of ammonium chloride and urea that could inhibit the mycelium growth and sporulation.