四氟醚唑手性异构体对植物病原真菌的活性差异

Bioactivity Differences of Tetraconazole Stereoisomers to Plant Pathogenic Fungi

[目的与方法]采用菌丝生长速率法,明确四氟醚唑手性异构体及外消旋体对小麦纹枯病菌、小麦赤霉病菌、水稻纹枯病菌、草莓灰霉病菌、大豆炭疽病菌的活性差异。[结果]四氟醚唑外消旋体对小麦纹枯病菌的抑菌活性最高,EC_(50)值为0.700 mg/L;对大豆炭疽的抑菌活性最弱,EC_(50)值为4.047 mg/L;对小麦赤霉病菌、水稻纹枯病菌、草莓灰霉病菌的抑菌活性也较强,EC_(50)值介于1.164~1.263 mg/L之间。(+)-四氟醚唑对5种菌抑菌活性高于(-)-四氟醚唑或外消旋体,(-)-四氟醚唑与(+)-四氟醚唑对小麦纹枯病菌、小麦赤霉病菌、水稻纹枯病菌、草莓灰霉病菌、大豆炭疽病菌的EC_(50)比值分别为1.49、1.98、1.69、4.11、2.01,其中对草莓灰霉病菌的抑菌活性差异最显著。[结论]四氟醚唑外消旋体及手性异构体对5种病原菌均有不同程度的抑菌活性,(+)-四氟醚唑为优映体。

[Aims and Methods] The study aims to confirm the bioactivity differences between tetraconazole stereoisomers and racemate tetraconazole to five plant pathogenic fungi（Fusarium graminearum, Rhizoctonia cerealis, Rhizoctonia solani, Botrytis cinerea Pers, Colletotrichum truncatum） by mycelial growth rate methods. [Results] The results showed that R. cerealis was the most sensitive one to racemate tetraconazole, with EC_（50） value of 0.700 mg/L, followed by F.graminearum, R. solani and B. cinerea Pers, with EC_（50） value of 1.164-1.263 mg/L, C. truncatum was the least sensitive one to racemate tetraconazole, with EC_（50） value of 4.047 mg/L. The inhibitory activity of（＋）-tetraconazole on five fungi were higher than（-）-tetraconazole or rac-tetraconazole. The EC_（50） ratio between（-）-tetraconazole and（＋）-tetraconazole to F. graminearum, R. cerealis, R. solani, B. cinerea Pers and C. truncatum were 1.49, 1.98, 1.69,4.11, 2.01, respectively. The most significant bioactivity difference was to B. cinerea Pers among them.[Conclusions] Tetraconazole stereoisomers and racemate tetraconazole have different inhibitory activities against five plant pathogenic fungi on mycelial growth, and（＋）-tetraconazole was eudomer.