College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China.
Key Laboratory of Integrated Crop Pest Management of Shandong Province, Qingdao, China.
Pest Manag Sci. 2020 Aug;76(8):2619-2626. doi: 10.1002/ps.5800. Epub 2020 Mar 12.
Non-target-site resistance (NTSR) to herbicides is a serious threat to global agriculture. Although metabolic resistance is the dominant mechanism of NTSR, the molecular mechanisms are not yet well-characterized. This study aimed to uncover the likely metabolism-related genes in Beckmannia syzigachne (American sloughgrass) resistant to fenoxaprop-p-ethyl.
Ultra-performance liquid chromatography - tandem mass spectrometry experiments showed that the resistant American sloughgrass biotype (R, SD-04-SS) showed enhanced degradation of this herbicide compared to the susceptible biotype (S, SD-12). R and S biotype were harvested at 24 h after fenoxaprop-p-ethyl treatment to conduct RNA sequencing (RNA-Seq) analysis to investigate the likely fenoxaprop-p-ethyl metabolic genes. The RNA-Seq libraries yield 417 969 980 clean reads. The de novo assembly generated 115 112 unigenes, of which 57 906 unigenes were annotated. Finally, we identified 273 cytochrome P450s, 178 oxidases, 47 glutathione S-transferases (GSTs), 166 glucosyltransferases (GTs) and 180 ABC transporter genes to determine the likely fenoxaprop-p-ethyl metabolism-related genes in R biotype. Twelve overlapping up-regulated genes in the R biotype (fenoxaprop-p-ethyl-treated R/non-treated R, fenoxaprop-p-ethyl-treated R/fenoxaprop-p-ethyl-treated S) were identified by RNA-Seq and the results were validated using qRT-PCR. Ten were identified as fenoxaprop-p-ethyl metabolism-related genes, including three P450s (homologous to CYP71D7, CYP99A2 and CYP71D10), one GST (homologous to GSTF1), two GTs (homologous to UGT90A1 and UGT83A1) and four oxidase genes.
This work demonstrates that the NTSR mechanism by means of enhanced detoxification of fenoxaprop-p-ethyl in American sloughgrass is very likely driven by herbicide metabolism related genes. The RNA-Seq data presented here provide a valuable resource for understanding the molecular mechanism of NTSR in American sloughgrass. © 2020 Society of Chemical Industry.
非靶标部位除草剂抗性（NTSR）是全球农业的严重威胁。尽管代谢抗性是 NTSR 的主要机制，但分子机制尚不清楚。本研究旨在揭示稗草（美国水稗草）对 fenoxaprop-p-ethyl 产生抗性的可能与代谢相关的基因。
超高效液相色谱-串联质谱实验表明，与敏感生物型（S，SD-12）相比，抗性稗草生物型（R，SD-04-SS）对该除草剂的降解能力增强。在 fenoxaprop-p-ethyl 处理后 24 小时收获 R 和 S 生物型进行 RNA 测序（RNA-Seq）分析，以研究可能的 fenoxaprop-p-ethyl 代谢基因。RNA-Seq 文库产生 417969980 条清洁读数。从头组装生成 115112 条 unigenes，其中 57906 条 unigenes被注释。最后，我们鉴定了 273 个细胞色素 P450s、178 个氧化酶、47 个谷胱甘肽 S-转移酶（GSTs）、166 个葡萄糖基转移酶（GTs）和 180 个 ABC 转运蛋白基因，以确定 R 生物型中可能的 fenoxaprop-p-ethyl 代谢相关基因。通过 RNA-Seq 鉴定了 12 个在 R 生物型中上调的重叠基因（fenoxaprop-p-ethyl 处理的 R/未处理的 R，fenoxaprop-p-ethyl 处理的 R/fenoxaprop-p-ethyl 处理的 S），并用 qRT-PCR 进行了验证。其中 10 个被鉴定为 fenoxaprop-p-ethyl 代谢相关基因，包括 3 个 P450s（与 CYP71D7、CYP99A2 和 CYP71D10 同源）、1 个 GST（与 GSTF1 同源）、2 个 GTs（与 UGT90A1 和 UGT83A1 同源）和 4 个氧化酶基因。
本研究表明，稗草通过增强 fenoxaprop-p-ethyl 的解毒作用产生的 NTSR 机制很可能是由与除草剂代谢相关的基因驱动的。本研究提供的 RNA-Seq 数据为了解稗草 NTSR 的分子机制提供了有价值的资源。© 2020 化学工业协会。
