Characterization of target-site resistance to ALS-inhibiting herbicides in Ammannia multiflora populations

Abstract

Ammannia multiflora Roxb. is a dominant broadleaf weed which is a serious problem in southern China rice fields, and ALS-inhibiting herbicides have been used for its control for a long time. Excessive reliance of ALS-inhibiting herbicides has led to herbicide resistance in A. multiflora. In this study, 10 A. multiflora populations from Jiangsu province of China were collected, and the resistance levels and target-site resistance mechanisms to ALS-inhibiting herbicides bensulfuron-methyl and penoxsulam were investigated. The dose response assays showed that 8 populations evolved resistance to bensulfuron-methyl (9.1 to 90.9-fold) and penoxsulam (5.0 to 103.1-fold). Amplification of ALS genes indicated that there were three ALS genes (AmALS1, AmALS2, and AmALS3) in A. multiflora. Sequence analysis revealed amino acid mutations at Pro197 in either AmALS1 (Pro-197-Ala, Pro-197-Ser, and Pro-197-His) or AmALS2 (Pro197Ser and Pro197Arg) in resistant populations, and no mutations were found in AmALS3. Moreover, two independent mutations (Pro197Ala in AmALS1 and Pro197Ser in AmALS2, or Pro197Ala in AmALS1 and Pro197Arg in AmALS2) coexisted in two resistant populations, respectively. In addition, the auxin mimic herbicides MCPA and florpyrauxifen-benzyl, PSII inhibitor bentazon and PPO inhibitor carfentrazone-ethyl can effectively control the resistant A. multiflora populations. Our study demonstrated the wide prevalence of ALS-inhibiting herbicides-resistant A. multiflora populations in Jiangsu province, the diversity of Pro197 mutations in ALS genes, and provides alternative herbicide options for controlling resistant A. multiflora populations.

Antioxidant Activities of Plant Extracts (Ammannia multiflora, Ammannia coccinea, and Salix gracilistyla) Activate the Nrf2/HO-1 Signaling Pathway

“…In this study, we tested the DPPH radical scavenging activity of 184 plant extracts and identified three extracts (FBCC-EP858 from A. multiflora, FBCC-EP920 from A. coccinea, and FBCC-EP1014 from S. gracilistyla) that possessed powerful antioxidant activity. A. multiflora, A. coccinea, and S. gracilistyla are plants known for their traditional medicinal uses, and their antioxidant properties were previously unknown or not well-characterized [21,27]. We found that these extracts enhanced antioxidant activity both in vitro and in vivo by activating the Nrf2/HO-1 pathway.…”

“…Ammannia multiflora is a plant belonging family Lythraceae and is well-known as an annual dicot weedy plant in agricultural lands and plants inhabiting aquatic environmental systems [21]. According to studies over the years, it has been proven that A. multiflora contains medicinal properties as it has shown antihyperglycemic activity, antimalarial properties, and microbicidal properties [21][22][23][24][25]. Regarding the biochemical and phytochemical analysis, the studies have revealed that it is rich in flavonoids, which may contribute to antioxidant activity [26].…”

Occurrence of Bensulfuron-Methyl Resistance and Target-Site Resistance Mechanisms in Ammannia auriculata Biotypes from Paddy Fields

“…Tanigali et al [ 33 ] found that the resistant mutations exclusively occurred in ALS1 or 3 in M. vaginalis . In our previous study, amino acid mutations in ALS1 or 2 independently, or in both, were found in Ammannia multiflora [ 34 ]. The preference of resistant mutations may be related to gene expression levels, herbicide use, and weed species.…”

Survey Reveals Frequency of Multiple Resistance to Tribenuron-Methyl, Bensulfuron-Methyl and Halosulfuron-Methyl in Cleavers (Galium aparine L.)

“…Several studies have found that ALS gene mutation or gene overexpression can lead to the resistance of weeds to ALS inhibitor herbicides, while the enhanced metabolic capacity mediated by cytochrome p450 oxidases can lead to the resistance of weeds to ALS inhibitor herbicides and herbicides with other action mechanisms [44][45][46][47][48][49]. We found that the population of cleavers in different regions of Jiangsu Province had obvious resistance to the ALS inhibitors such as tribenuron-methyl, bensulfuron-methyl and halosulfuronmethyl, but was sensitive to the auxin herbicides and PPO inhibitors.…”