Department of Agronomy and Horticulture, IPB University, Bogor, Indonesia.
PLoS One. 2024 Oct 4;19(10):e0308465. doi: 10.1371/journal.pone.0308465. eCollection 2024.
The most bothersome weed in rice fields in the Indonesian province of West Java is Monochoria vaginalis (Burm. F.) C. Presl, an aquatic herbaceous plant. Metsulfuron-methyl has long been used in wetland rice in West Java with a high enough intensity. However, the case of Monochoria vaginalis resistance to metsulfuron-methyl herbicides in Indonesia has not been widely reported and investigated. The study aims to (1) classify the resistance level of M. vaginalis toward metsulfuron-methyl, (2) identify Target Site Resistance (TSR) mechanism mutations in the MvALS1 gene of the resistant biotype of M. vaginalis. The Whole Plant Pot Test method was utilized to assess the resistance level of Monochoria vaginalis. Following that, all samples were subjected to DNA sequencing using the PCR method to identify mutations in the MvALS1 gene from the resistant biotype. After then, this study used DUET, a server with an integrated computational methodology, to anticipate the effect of mutations on protein stability. The result showed that Monochoria vaginalis from Rawamerta, Karawang showed a moderate level of resistance to metsulfuron-methyl with a resistance ratio of 6.00, Patokbeusi, Subang showed a low level of resistance to metsulfuron-methyl with a resistance ratio of 3.89, compared to susceptible Monochoria vaginalis. Nucleotide base alignment in the MvALS1 gene revealed that base substitutions occurred in the Monochoria vaginalis biotype from Rawamerta and Patokbeusi, resulting in 5 amino acid substitutions: Ser-64-Ala, Asp-66-Glu, Asn-240-Asp, Glu-426-Asn, and Ser-469-Asn and Sukra: Ser-64-Ala, Asp-66-Glu, and Asn-240-Asp. The analysis showed that S64A, D66E, and N240D stabilize the protein, whereas E426N and S469N destabilize it. This study confirms for the first time that Ser-64-Ala, Asn-240-Asp, and Glu-426-Asn amino acid mutations were found in cases of M. vaginalis resistance to metsulfuron-methyl (ALS inhibitor).
印度尼西亚西爪哇省稻田中最令人讨厌的杂草是水鳖 Monochoria vaginalis（Burm. F.）C. Presl，一种水生草本植物。甲磺隆甲酯在西爪哇的湿地水稻中已被长期大量使用。然而，关于印度尼西亚 M. vaginalis 对甲磺隆甲酯除草剂的抗药性问题尚未得到广泛报道和研究。本研究旨在：（1）对 M. vaginalis 对甲磺隆甲酯的抗药性水平进行分类；（2）鉴定抗药性 M. vaginalis 生物型 MvALS1 基因的靶标位点抗性（TSR）机制突变。采用全株盆栽试验法评估 M. vaginalis 的抗药性水平。随后，所有样本均采用 PCR 法进行 DNA 测序，以鉴定抗药性生物型 MvALS1 基因的突变。然后，本研究使用 DUET 服务器，这是一个集成计算方法的服务器，来预测突变对蛋白质稳定性的影响。结果表明，来自拉瓦梅塔（Rawamerta）和卡拉旺（Karawang）的 M. vaginalis 对甲磺隆甲酯表现出中等水平的抗性，抗性比为 6.00，而来自帕托克布西（Patokbeusi）和苏邦（Subang）的 M. vaginalis 对甲磺隆甲酯表现出低水平的抗性，抗性比为 3.89，与敏感的 M. vaginalis 相比。MvALS1 基因的核苷酸碱基比对显示，在拉瓦梅塔和帕托克布西的 M. vaginalis 生物型中发生了碱基替换，导致 5 个氨基酸替换：丝氨酸-64-丙氨酸、天冬氨酸-66-谷氨酸、天冬酰胺-240-天冬氨酸、谷氨酸-426-天冬酰胺和丝氨酸-469-天冬酰胺以及苏克拉：丝氨酸-64-丙氨酸、天冬氨酸-66-谷氨酸和天冬酰胺-240-天冬氨酸。分析表明，S64A、D66E 和 N240D 稳定了蛋白质，而 E426N 和 S469N 则使其不稳定。本研究首次证实，在 M. vaginalis 对甲磺隆甲酯（ALS 抑制剂）的抗药性情况下，发现了丝氨酸-64-丙氨酸、天冬酰胺-240-天冬氨酸和谷氨酸-426-天冬酰胺的氨基酸突变。
