马蹄金白绢病生物学特性的研究

Study on the Biological Characteristic of Southern Sclerotium Blight in Dichondra repens

研究了马蹄金白绢病的生物学特性，结果表明：马蹄金白绢病菌在5～35℃条件均能生长，以25℃生长最优；在pH值为3．0～10．0均能生长，适宜生长的pH值为5．0～6．0。马蹄金白绢病菌的菌丝能较好地利用不同碳源，但利用程度不同，以蔗糖利用效果最好，其次为葡萄糖和半乳糖，果糖次之，可溶淀粉最差；马蹄金白绢病菌能不同程度地利用有机氮源和无机氯源，在固体培养基中对硝态氮的利用能力最好，有机氮（尿素乙酸铵）次之，无机铵盐（硫酸铵）最差；不同光照时间对马蹄金白绢病的影响不同，以全部黑暗条件下培养菌丝生长最快，光和暗交替培养菌丝生长速度次之，全部光照条件下培养菌丝其生长速度最低。

The biological characteristics of southern scleretium blight in Dichondra repens were studied and the results showed that Sclerotium rolfsii in D. repens could grow in 5 - 35 ℃ and its growth at 25 ℃ was best, and it could grow in pH values of 3.0 - 10.0 and the suitable pH value for its growth was in 5.0 - 6.0. The hypha of S. rolfsii in D. repens could utilize different carbon sources better to different degrees, the utilization effect was best on sucres, secondary on glucose and galactose, tertiary on fructose and worst on soluble starch. S. rolfsii in D. repens could utilize organic and inorganic nitrogen sources to different degrees, in solid medium, its utilization ability was best on nitrate nitrogen, secondary on organic nitrogen （urea and ammonium acetate） and worst on inorganic ammonium salt （ammonium sulfate）. Different illumination time had different influences on S. rolfsii in D. repens, the growth velocity of hypha cuhured in complete dark was fastest, that cultured in alternation of light and dark was secondary and that cultured in complete light was lowest.