Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Agriculture & Key Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province , South China Agricultural University , Wushan Road 483 , Tianhe District, Guangzhou , 510642 , China.
J Agric Food Chem. 2018 Apr 11;66(14):3637-3643. doi: 10.1021/acs.jafc.7b05483. Epub 2018 Mar 26.
Tebuconazole, which consists of a pair of enantiomers with different fungicidal activities, is one of the most common fungicides used in the control of Fusarium graminearum. In this study, the fungicidal activity of rac-tebuconazole and its enantiomers against F. graminearum was determined at 0.997, 0.975, and 0.950 a and at 20, 25, and 30 °C on wheat-based media. Then, F. graminearum was treated with rac-tebuconazole and its enantiomers at the EC, EC, and EC levels under different culture conditions, and DON production was measured. Finally, expression of the DON biosynthetic genes ( TRI5 and TRI6) was quantified by real-time RT-PCR after incubation with EC doses of rac-tebuconazole and its enantiomers for 4, 8, and 14 days at 30 °C and a 0.997. The results showed that the fungicidal activity of tebuconazole was strongly influenced by temperature, a, and the combined factors. (-)-Tebuconazole is higher in fungicidal activity than (+)-tebuconazole and rac-tebuconazole with 24-99-fold and 1.8-6.7-fold, respectively. However, (-)-tebuconazole was generally more favorable for DON production than (+)-tebuconazole under the same conditions. Additionally, (-)-tebuconazole and rac-tebuconazole induced significantly increased expression of the DON biosynthetic genes ( TRI5 and TRI6) compared to the control by the 14th day of treatment. In this research, the combination condition of 30 °C and 0.997 a is the most suitable for DON production by F. graminearum. The test strains of F. graminearum treated with the EC dose of (-)-tebuconazole produced the greatest amounts of DON.
戊唑醇由一对具有不同杀菌活性的对映异构体组成，是防治禾谷镰刀菌(Fusarium graminearum)最常用的杀菌剂之一。本研究在小麦培养基上，于 0.997、0.975 和 0.950 a 和 20、25 和 30°C 条件下，测定了 rac-戊唑醇及其对映异构体对禾谷镰刀菌的杀菌活性。然后，在不同培养条件下，用 rac-戊唑醇及其对映异构体在 EC、EC 和 EC 水平处理禾谷镰刀菌，并测定 DON 的产量。最后，在 30°C 和 0.997 a 下用 rac-戊唑醇及其对映异构体的 EC 剂量处理 4、8 和 14 天，通过实时 RT-PCR 定量测定 DON 生物合成基因（TRI5 和 TRI6）的表达。结果表明，戊唑醇的杀菌活性受温度、a 和组合因素的强烈影响。(-)-戊唑醇的杀菌活性比(+)-戊唑醇和 rac-戊唑醇分别高 24-99 倍和 1.8-6.7 倍。然而，在相同条件下，(-)-戊唑醇通常比(+)-戊唑醇更有利于 DON 的产生。此外，与对照相比，(-)-戊唑醇和 rac-戊唑醇在第 14 天处理时显著增加了 DON 生物合成基因(TRI5 和 TRI6)的表达。在本研究中，30°C 和 0.997 a 的组合条件最适合禾谷镰刀菌产生 DON。用(-)-戊唑醇 EC 剂量处理的禾谷镰刀菌测试菌株产生的 DON 量最大。
