马铃薯黄萎病菌生物学特性及室内药剂筛选

对马铃薯黄萎病两种病原菌的生物学特性以及室内药剂筛选进行了测定.结果表明,两种病原VertiG cillium alboGatrum Reinke ＆ Berthold 和V．dahliae Kleb．的生物学特性具有部分共同点：生长温度范围均为10~35℃,都能够利用5种供试培养基和5种供试碳源.但在其他方面存在较多差异：V．alboGatrum菌丝生长最适培养基为梅干煎汁培养基,最适温度20℃,酸碱度生长范围为 pH 值5.0~11.0,最适 pH 值8．0,最适碳、氮源为甘油和磷酸铵；而V．dahliae 菌丝生长最适培养基为改良查氏2号培养基,最适温度25℃,酸碱度生长范围为 pH 值5．0~12．0,最适 pH 值7.5,最适碳、氮源为蔗糖和硝酸钠.药剂筛选试验结果表明：50％苯并咪唑、70％甲基硫菌灵及75％百菌清表现出良好抑菌作用,EC50值≤4．05 mg/L.

Biological Characteristics of the Pathogens Causing the Verticillium Wilt of Potato and Selection of Fungicides in Laboratory

The purpose of this paper was to study the biological characteristics of the pathogens causing the verticillium wilt of potato and the inhibitory effect of fungicides in laboratory.The results showed the biological characteristics of the 2 kinds of pathogens of verticillium wilt of potato：Verticillium alboGatrum Reinke ＆amp; Berth and V.dahliae Kleb were basically the same.Both of their temperature for mycelial growth was from 10 ℃ to 35 ℃.Five tested mediums and five tested carbon sources could be used by them. Besides,there were more differences between the 2 pathogens.The optimum medium of V.alboGatrum, mycelial growth was PLYA medium.The optimum temperature was 20 ℃ and the optimum acidbase pH was 8.0 for hypha growth.The optimum carbon and nitrogen source came from （NH4 ）3 PO4 .The optimum medium V.dahliae,of mycedium was the No.2 improved Czapek medium.The optimum temperature was 25 ℃ and the optimum acidbase pH was 7.5 for hypha growth.The hypha could grow best on the culture whose carbon source came from sucrose and nitrogen source came from NaNO3 .The results of fungidides selection in laboratory showed that 50% carbendazim,70% thiophanateGmethyl and 75% chlorothalonil proved to be the most effective fungicides,their 50% effective concentration value was less than or epual to 4.05 mg/L.