草莓枯萎病菌的分离鉴定及防治药剂筛选
Isolation and Identification of Strawberry Fusarium Wilt Pathogen and Fungicides Screening

草莓枯萎病是目前危害北京草莓产业的主要病害，为筛选出安全有效的杀菌剂，采用组织分离法从北京昌平地区采集的草莓枯萎病株中分离到引起草莓枯萎病的病原菌。经形态学和分子生物学手段鉴定该病原菌为尖孢镰刀菌草莓专化型（Fusarium oxysporum Schlecht f.sp.fragariae Winks et Williams）。采用菌丝生长速率法对14种杀菌剂进行筛选，其中，206.7 g/L噁酮·氟硅唑、寡雄腐霉、φ=25%腈菌唑、w=60%嘧菌酯、w=70%代森锰锌、w=75%百菌清、w=50%异菌脲7种杀菌剂对草莓枯萎病具有显著的抑菌效果，其EC50值分别为0.003、0.63、0.73、5.91、8.90、78.54、229.09 mg/L；另外，206.7 g/L 噁酮·氟硅唑、寡雄腐霉、w=70%代森锰锌和w=75%百菌清4种杀菌剂的药效可持续96 h以上，其他3种药剂处理48 h后对草莓枯萎病的抑制效果显著下降。因此，206.7 g/L噁酮·氟硅唑、寡雄腐霉、w=70%代森锰锌和w=75%百菌清是草莓枯萎病防治的优先选择。
Strawberry Fusarium wilt is a major threat of strawberry industry in Beijing. In order to screen for the safe and effective fungicides to control strawberry Fusarium wilt spreading in Beijing area,tissue isolation method were used to isolate the casual agent that caused Fusarium wilt of the strawberry in Changping district of Beijing.The pathogen was identified as Fusarium oxysporum Schlecht f. sp. fragariae Winks et Williams through morphological,molecular biological methods and pathogenicity analysis. Subsequently,14 fungicides were screened by the mycelium growth rate method. According to the value of EC50,7 fungicides showed significant inhibitory effect on the pathogen of strawberry Fusarium wilt,which were 206.7 g/L famoxadone · flusilazole,Pythium oligandrum,φ=25% myclobutanil,w=60% azoxystrobin,w=70% mancozeb,w=75% chlorothalonil,and w=50% iprodione,which EC50 value is respectively 0.003,0.63,0.73,5.91,8.90,78.54,and 229.09 mg/L. Moreover,inhibitory effect of 4 fungicides,including 206.7 g/L famoxadone · flusilazole,Pythium oligandrum,w=70% mancozeb,and w=75% chlorothalonil,lasted for 96 h; however,the inhibitory effect of the remaining 3 fungicides significantly decreased after 48 h. Therefore,4 fungicides,including 206.7 g/L famoxadone · flusilazole,Pythium oligandrum,w=70% mancozeb and w=75% chlorothalonil,are the best choice of field fungicide application for strawberry Fusarium wilt.