Herbicides Toxicology and Weeds Herbicide-Resistant Mechanism—Series II

A special issue of Agronomy (ISSN 2073-4395). This special issue belongs to the section "Weed Science and Weed Management".

Deadline for manuscript submissions: 31 May 2025 | Viewed by 16670

Special Issue Editor

College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
Interests: weed biology and management; herbicide toxicology and resistance
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Weeds have become an increasing threat to agriculture production. The management of weeds relies heavily on herbicides and causes consequent weed resistance to herbicides, which has been an un-neglectable issue for farmers and weed scientists. Many efforts have been put into the exploring of herbicide toxicology and resistance mechanisms, and many resistance mechanisms for reported resistance cases have been reported. However, more knowledge on herbicide toxicology and resistance are still needed to obtain a better understanding of weed resistance in order to take reasonable resistance management measures, as cases of resistance keep arising.

The aim and scope of this Special Issue are the biochemical and molecular modes of action of herbicides, biochemical and molecular resistance mechanisms of weeds to herbicides, especially cutting-edge research on the molecular modes of action of novel herbicides, and novel resistance mechanisms for weeds to herbicides which have never been reported.

We are soliciting papers that cover the following topics:

  • Molecular modes of action of novel herbicides;
  • Target-site-based resistance mechanisms for novel resistance cases;
  • Non-target-site-based resistance mechanisms for major weeds in crop system;
  • Fitness cost of herbicide-resistant weeds.

Dr. Jun Li
Guest Editor

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Keywords

  • herbicide toxicology
  • herbicide-resistant weeds
  • herbicide resistance
  • resistance mechanisms to herbicides

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Published Papers (11 papers)

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Research

13 pages, 817 KiB  
Article
Resistance to Acetyl Coenzyme A Carboxylase (ACCase) Inhibitor in Lolium multiflorum: Effect of Multiple Target-Site Mutations
by Gulab Rangani, Ana Claudia Langaro, Shilpi Agrawal, Reiofeli A. Salas-Perez, Juan Camilo Velásquez, Christopher E. Nelson and Nilda Roma-Burgos
Agronomy 2024, 14(10), 2316; https://doi.org/10.3390/agronomy14102316 - 9 Oct 2024
Viewed by 571
Abstract
Italian ryegrass (Lolium multiflorum Lam.) is a persistent weed species that poses significant management challenges in key agricultural crops such as wheat, corn, cotton, and soybean. This study investigated the prevalence of resistance to ACCase inhibitor herbicides, specifically diclofop and pinoxaden, among [...] Read more.
Italian ryegrass (Lolium multiflorum Lam.) is a persistent weed species that poses significant management challenges in key agricultural crops such as wheat, corn, cotton, and soybean. This study investigated the prevalence of resistance to ACCase inhibitor herbicides, specifically diclofop and pinoxaden, among field-collected Italian ryegrass populations. The survey revealed widespread resistance to diclofop and emerging cross-resistance to pinoxaden. To elucidate the physiological mechanism of ACCase herbicide resistance, we investigated mutations in the carboxyl-transferase (CT) domain of the ACCase enzyme, a critical region for herbicide sensitivity. Using dCAPS assays and CT domain sequencing, several known resistance-conferring mutations were detected in diclofop survivors, including I1781L, W2027C, I2041N, D2078G, and C2088R. Additionally, other mutations such as L1701M, E1874A, N1878H, G1946E/Q, V1992D, and E2039D were identified. To understand the functional role of these mutations in herbicide resistance, homology modeling was performed using AutoDock Vina for selected mutation combinations. The computational analysis revealed that all mutations and their combinations resulted in reduced binding affinity with diclofop and pinoxaden compared to the wild-type ACCase CT domain. Computational binding energy predictions indicated that the G1946E mutation and the L1701M + I1781L + E1874A + N1878H combination exhibited the lowest affinities for diclofop and pinoxaden, respectively. This study provides valuable insights into the molecular basis of ACCase inhibitor resistance in Italian ryegrass. However, further research is needed to validate the functional significance of each new substitution and its combinations in conferring herbicide resistance. Full article
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15 pages, 5319 KiB  
Article
Synthesis, Herbicidal Activity, and Molecular Mode of Action Evaluation of Novel Quinazolinone—Phenoxypropionate Hybrids Containing a Diester Moiety
by Shumin Wang, Na Li, Shibo Han, Shuyue Fu, Ke Chen, Wenjing Cheng and Kang Lei
Agronomy 2024, 14(9), 2124; https://doi.org/10.3390/agronomy14092124 - 18 Sep 2024
Viewed by 554
Abstract
To develop aryloxyphenoxypropionate herbicides with novel structure and improved activity, a total of twenty-eight novel quinazolinone–phenoxypropionate derivatives containing a diester moiety were designed and synthesized. The herbicidal bioassay results in the greenhouse showed that QPEP-I-4 exhibited excellent herbicidal activity against E. crusgalli, [...] Read more.
To develop aryloxyphenoxypropionate herbicides with novel structure and improved activity, a total of twenty-eight novel quinazolinone–phenoxypropionate derivatives containing a diester moiety were designed and synthesized. The herbicidal bioassay results in the greenhouse showed that QPEP-I-4 exhibited excellent herbicidal activity against E. crusgalli, D. sanguinalis, S. alterniflora, E. indica, and P. alopecuroides with inhibition rates >80% at a dosage of 150 g ha−1 and displayed higher crop safety to G. hirsutum, G. max, and A. hypogaea than the commercial herbicide quizalofop-p-ethyl. Studying the herbicidal mechanism by phenotypic observation, membrane permeability evaluation, and transcriptomic analysis revealed that a growth inhibition of plants by QPPE-I-4 was the result from damage of the plants’ biomembrane. The evaluation of ACCase activity in vivo indicated that QPPE-I-4 could inhibit ACCase and may be a new type of ACCase inhibitor. The present work indicated that QPPE-I-4 could represent a lead compound for further developing novel AOPP herbicides. Full article
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7 pages, 911 KiB  
Communication
Chlorophyll Fluorescence Imaging Reveals the Dynamics of Bentazon Action on Sunflower (Helianthus annuus L.) Plants
by Mikhail Bazhenov, Dmitry Litvinov, Alina Kocheshkova, Gennady Karlov and Mikhail Divashuk
Agronomy 2024, 14(8), 1748; https://doi.org/10.3390/agronomy14081748 - 9 Aug 2024
Viewed by 619
Abstract
Fluorescence photography was used to evaluate the effects of bentazon, an herbicide that inhibits electron transport in photosystem II, on sunflower, taken as a model plant. We measured chlorophyll fluorescence to visualize the penetration, distribution, and effect of the herbicide on the plant. [...] Read more.
Fluorescence photography was used to evaluate the effects of bentazon, an herbicide that inhibits electron transport in photosystem II, on sunflower, taken as a model plant. We measured chlorophyll fluorescence to visualize the penetration, distribution, and effect of the herbicide on the plant. Our results showed that bentazon penetrates the leaf within 10–16 min, reaching full depth within 40 min. Also, we show that the herbicide is distributed along the conducting tissues of the leaf. The presence of necrotic spots, as well as the size of increased-fluorescence areas, were positively correlated to the concentration of herbicide. These findings suggest that fluorescence imaging may be a useful tool for observing the absorption and distribution of photosystem II-inhibiting herbicides in plants as an alternative to radioactive labeling in some cases. Full article
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12 pages, 1531 KiB  
Article
Reduced Translocation Confers Paraquat Resistance in Plantago lanceolata
by Vhuthu Ndou, Deon Kotze, Biljana Marjanovic-Painter, Ethel E. Phiri, Petrus J. Pieterse and Molahlehi S. Sonopo
Agronomy 2024, 14(5), 977; https://doi.org/10.3390/agronomy14050977 - 6 May 2024
Viewed by 1043
Abstract
Ribwort plantain (Plantago lanceolata L.) is a common weed in the winter rainfall region of South Africa. This weed is widespread across vineyards, orchards, and roadsides in the region. The weed has already evolved resistance to glyphosate and paraquat; however, the mechanism [...] Read more.
Ribwort plantain (Plantago lanceolata L.) is a common weed in the winter rainfall region of South Africa. This weed is widespread across vineyards, orchards, and roadsides in the region. The weed has already evolved resistance to glyphosate and paraquat; however, the mechanism of paraquat resistance has not been documented. This study aimed to investigate the resistance mechanisms in this resistant (R) biotype. Dose–response trials conducted with R biotypes from the Robertson area reconfirmed paraquat resistance. Dose–response trials established that the paraquat rate causing 50% mortality (LD50) for the R biotype is three times greater than for the susceptible (S) biotype. To find out how paraquat affected the photosynthetic performance of P. lanceolata, the quantum yield of photosystem II was measured. The photosystem reaction centres of the R biotype recovered 24 h after paraquat treatment. To evaluate paraquat transport in the plant cell, selective transport inhibitors were applied. Plantago lanceolata (S) biotypes had the highest electrolyte leakage after paraquat treatment. A combined radio/UV-HPLC was used for the separation and identification of paraquat and its metabolites. Paraquat degradation was not observed, indicating that metabolism was not a resistance mechanism within the R biotype. To assess leaf absorption and translocation, [14C]-labelled paraquat was applied to fully expanded leaves. There were no significant differences in paraquat absorption. However, paraquat translocation differed significantly across the R and S biotypes, indicating that non-target site resistance through reduced paraquat translocation was the main mechanism of resistance in the R biotype. As the resistance of weed species to post-emergence herbicides continues to increase, achieving sustainable weed management necessitates the implementation of diversified weed control strategies. Full article
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12 pages, 1030 KiB  
Article
Herbicidal Activity of Cinmethylin against Grass Weeds and Its Safety for Use with Different Wheat Varieties
by Hongle Xu, Qiuli Leng, Wangcang Su, Lanlan Sun, Jingping Cheng and Renhai Wu
Agronomy 2024, 14(5), 885; https://doi.org/10.3390/agronomy14050885 - 24 Apr 2024
Viewed by 966
Abstract
Cinmethylin is a potential pre-emergence herbicide that could be used to control grass weeds in winter cereals. To determine the herbicidal activity of cinmethylin against common gramineous weeds in wheat fields in China and its level of safety on wheat, we conducted the [...] Read more.
Cinmethylin is a potential pre-emergence herbicide that could be used to control grass weeds in winter cereals. To determine the herbicidal activity of cinmethylin against common gramineous weeds in wheat fields in China and its level of safety on wheat, we conducted the following experiments: (i) assessing the efficacy of cinmethylin against 11 grass weeds and (ii) determining its safety against 19 wheat varieties. The results showed that cinmethylin had good herbicidal efficacy against annual bluegrass (Poa annua L.), shortawn foxtail (Alopecurus aequalis Sobol.), slender meadow foxtail (Alopecurus myosuroides Huds.), Japanese foxtail (Alopecurus japonicus Steud.), Italian ryegrass (Lolium multiflorum Lam.), British timothy (Phleum paniculatum Huds.), Asia Minor bluegrass (Polypogon fugax Nees ex Steud.), Helictotrichon tibeticum (Roshev.) Holub., and wild oat (Avena fatua L.), with a GR50 (the herbicide dose resulting in 50% growth inhibition) value of 4.50–99.21 g a.i. ha−1 in plant height and 1.43–70.34 g a.i. ha−1 in fresh weight. However, cinmethylin cannot control Japanese brome (Bromus japonicus L.) or Tausch’s goatgrass (Aegilops tauschii Coss.) at a dose of 200 g a.i. ha−1. Different wheat varieties varied in their phytotoxicity to cinmethylin. Overall, there is a phytotoxicity risk when using cinmethylin on wheat, mainly to wheat roots, with a reduction in root length of 40.81–64.09% at a dose of 400 g a.i. ha−1. These findings indicate that the pre-emergence herbicide cinmethylin provides good efficacy against most grass weeds and may possess potential for weed management in wheat fields. However, attention should be given to the application dosage and the sensitivity of wheat varieties when using cinmethylin in wheat fields. Full article
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10 pages, 579 KiB  
Article
Management of Eleusine indica (L.) Gaertn Resistance to Glyphosate Herbicide in Indonesia
by Denny Kurniadie, Ryan Widianto, Uum Umiyati, Dedi Widayat, Ceppy Nasahi and Ari Budiawan
Agronomy 2023, 13(6), 1649; https://doi.org/10.3390/agronomy13061649 - 20 Jun 2023
Cited by 3 | Viewed by 2772
Abstract
Eleusine indica (L.) Gaertn, commonly known as goosegrass or wiregrass, is a type of grass that is widespread in many parts of the world. The broad-spectrum herbicide glyphosate is most frequently used in Indonesian oil palm plantations to get rid of weeds and [...] Read more.
Eleusine indica (L.) Gaertn, commonly known as goosegrass or wiregrass, is a type of grass that is widespread in many parts of the world. The broad-spectrum herbicide glyphosate is most frequently used in Indonesian oil palm plantations to get rid of weeds and other undesirable plants. However, improper rotation of herbicide types by farmers has led to an increased risk of resistant weed emergence. This investigation tries to validate E. indica’s glyphosate resistance, investigate mutations in the EPSPS gene of the resistant biotype, and determine the type of herbicides that can control E. indica glyphosate-resistant biotypes. The whole plant pot test method was used to measure the resistance level, while DNA sequencing using the PCR method was conducted on all samples to identify mutations in the EPSPS gene of the resistant biotype. The study results showed that all biotypes of E. indica were identified as resistant to glyphosate but susceptible to propaquizafop, ametryn, and sulfentrazone herbicides. Several biotypes, such as the North Sumatra biotype, were identified as having multiple resistances to glyphosate, paraquat, and ammonium glufosinate. Thr102Iso and Pro106Ser amino acid substitutions were found in the EPSPS gene of E. indica-resistant biotypes. The findings of this study showed that E. indica was resistant to paraquat and ammonium glufosinate; further research is required to determine the mechanism. Full article
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15 pages, 2609 KiB  
Article
Nontarget Site-Based Resistance to Fenoxaprop-P-ethyl and Candidate Genes Involved in Alopecurus japonicus
by Hongle Xu, Xiaofan Ye, Shaoqi Liang, Jingping Cheng, Qiuli Leng, Lanlan Sun, Wangcang Su, Fei Xue, Liyao Dong and Renhai Wu
Agronomy 2023, 13(6), 1587; https://doi.org/10.3390/agronomy13061587 - 12 Jun 2023
Viewed by 1458
Abstract
Nontarget-site resistance (NTSR) is a complex multigenic trait that is associated with the potential mechanisms of herbicide resistance which pose a serious threat to global crop protection. However, the NTSR mechanisms of Alopecurus japonicus, a malignant weed infesting wheat fields, are less [...] Read more.
Nontarget-site resistance (NTSR) is a complex multigenic trait that is associated with the potential mechanisms of herbicide resistance which pose a serious threat to global crop protection. However, the NTSR mechanisms of Alopecurus japonicus, a malignant weed infesting wheat fields, are less characterized. In this study, we used RNA-sequencing transcriptome and enzyme activity detection to investigate the NTSR mechanisms and candidate genes involved in fenoxaprop-P-ethyl (FE) in a previously identified resistant population compared to the sensitive population of A. japonicus. Transcriptome analysis identified nine upregulated genes, which were constitutively overexpressed and upregulated by FE application in the resistant population, and the results were validated using quantitative real-time PCR. These genes including one cytochrome P450 monooxygenase (P450) gene (CYP75B4), one ATP-binding cassette (ABC) transporter gene (ABCG36), one laccase (LAC) gene (LAC15), one 9-cis-epoxycarotenoid dioxygenase (NCED) gene (NCED5), two purple acid phosphatase (PAP) genes (PAP4, PAP15), one sucrose phosphate synthase (SPS) gene (SPS3), one protein related to disease resistance gene (RGA3) and one immune protein gene (R1B-17). The activity assay of LAC, NCED, PAP and SPS revealed that the activities of these enzymes in the resistant population were significantly higher than those in the sensitive population at 0 h and after FE application at 12 h, 24 h and 72 h. Nevertheless, whether LAC, NCED, PAP and SPS genes were involved in herbicide metabolism needs to be further validated. Our results revealed that CYP, ABC transporter and LAC genes may participate in A. japonicus resistance. These genes identified in the present study provide new insights into the resistance mechanism of weeds in response to herbicide. Our study also implies the complexity of the NTSR mechanisms of weeds. Full article
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12 pages, 2857 KiB  
Article
Molecular Basis of Resistance to Bensulfuron-Methyl in a Smallflower Umbrella Sedge (Cyperus difformis L.) Population from China
by Shanshan Yin, Wei Hu, Yin Chai, Minghao Jiang, Jingxu Zhang, Haiqun Cao, Ning Zhao and Min Liao
Agronomy 2023, 13(4), 1179; https://doi.org/10.3390/agronomy13041179 - 21 Apr 2023
Cited by 3 | Viewed by 1952
Abstract
Smallflower umbrella sedge (Cyperus difformis L.) is an invasive weed, and infestations of C. difformis are increasing in rice (Oryza sativa L.) fields in China. Bensulfuron-methyl is a widely used sulfonylurea herbicide that inhibits the acetolactate synthase (ALS) enzyme and [...] Read more.
Smallflower umbrella sedge (Cyperus difformis L.) is an invasive weed, and infestations of C. difformis are increasing in rice (Oryza sativa L.) fields in China. Bensulfuron-methyl is a widely used sulfonylurea herbicide that inhibits the acetolactate synthase (ALS) enzyme and has been used in recent years for effectively controlling annual weeds in the Cyperaceae family. In this study, a suspected resistant population of C. difformis (BBHY1) was collected from a rice field in Huaiyuan County, Anhui Province, China, that survived treatment with bensulfuron-methyl at the field-recommended rate (FRR). Single-dose tests and whole-plant bioassays confirmed that the BBHY1 population was resistant to bensulfuron-methyl and had evolved a high level of resistance, with a resistance index (RI) of 12.87. Sequencing of the ALS gene revealed a CCT to CAT point mutation at codon 197, which caused a P-to-H substitution in the resistant plants. Analysis of the relative expression of ALS revealed no significant differences between the resistant and susceptible populations. Inhibiting the activity of cytochrome P450s (P450s) or glutathione S-transferases (GSTs) had no significant effect on bensulfuron-methyl resistance. The BBHY1 population exhibited cross-resistance to pyrazosulfuron-ethyl, penoxsulam, and bispyribac-sodium, with RIs ranging from 5.48 to 20.63, but remained susceptible to MCPA sodium, florpyrauxifen-benzyl, and bentazon, with RIs of <1.00. These herbicides could be potentially used as alternatives for controlling resistant populations and managing herbicide resistance in other aggressive weeds in rice fields. Full article
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14 pages, 2372 KiB  
Article
Detection of Resistance in Echinochloa spp. to Three Post-Emergence Herbicides (Penoxsulam, Metamifop, and Quinclorac) Used in China
by Yangyang Zhang, Miao Wu, Shuijing Bao, Jiamin Li, Dingrong Liu, Liyao Dong and Jun Li
Agronomy 2023, 13(3), 841; https://doi.org/10.3390/agronomy13030841 - 13 Mar 2023
Cited by 1 | Viewed by 1567
Abstract
In this study, rapid resistance in-season quick (RISQ) tests were developed for detecting the resistance in Echinochloa spp. to penoxsulam, metamifop, and quinclorac, which are widely used in rice fields to control E. spp. biotypes. Seedlings in 1–2 leaf stages from nine biotypes [...] Read more.
In this study, rapid resistance in-season quick (RISQ) tests were developed for detecting the resistance in Echinochloa spp. to penoxsulam, metamifop, and quinclorac, which are widely used in rice fields to control E. spp. biotypes. Seedlings in 1–2 leaf stages from nine biotypes of E. crusgalli, E. crusgalli var. zelayensis, and E. glabrescens, with different susceptibility to the three herbicides tested, were transplanted to plates containing nutrient agar and different rates of herbicides. The survival rates were recorded at 8 days after treatment when no more new roots emerged for all the treatments. By comparing the results from RISQ tests and whole-plant pot bioassays statistically, discrimination rates could be determined to distinguish resistant plants from susceptible plants. For penoxsulam, metamifop, and quinclorac, the discrimination rates were 0.3, 0.6, and 2.4 µmol/L, respectively. Two additional biotypes of E. crusgalli collected in rice fields were used to confirm the validation of the RISQ test and the obtained results by the RISQ test were consistent with that of the whole-plant pot bioassay. Therefore, the developed RISQ test would be a possible alternative method to determine the susceptibility of E. spp. to certain herbicides. Full article
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16 pages, 2795 KiB  
Article
Comparative Transcriptome Analysis of the Differential Effects of Florpyrauxifen-Benzyl Treatment on Phytohormone Transduction between Florpyrauxifen-Benzyl-Resistant and -Susceptible Barnyard Grasses (Echinochloa crus-galli (L.) P. Beauv)
by Wenyong Jin, Jinqiu Sun, Wei Tang, Yongjie Yang, Jianping Zhang, Yongliang Lu and Xiaoyue Yu
Agronomy 2023, 13(3), 702; https://doi.org/10.3390/agronomy13030702 - 27 Feb 2023
Cited by 5 | Viewed by 1949
Abstract
Echinochloa crus-galli (L.) P. Beauv (common name: barnyard grass) is a major weed in rice-growing areas and has evolved resistance to multiple herbicides. Florpyrauxifen-benzyl (trade name Rinskor) is a novel synthetic auxin herbicide that was approved in China in 2017 and is widely [...] Read more.
Echinochloa crus-galli (L.) P. Beauv (common name: barnyard grass) is a major weed in rice-growing areas and has evolved resistance to multiple herbicides. Florpyrauxifen-benzyl (trade name Rinskor) is a novel synthetic auxin herbicide that was approved in China in 2017 and is widely used in rice production to control resistant weeds, including barnyard grass. We identified a florpyrauxifen-benzyl-resistant E. crus-galli biotype with a resistance index (RI) of 11.89 using screen house herbicide experiments. To understand the phytotoxicity mechanisms of florpyrauxifen-benzyl, we used transcriptomics technologies to compare the gene expression profiles of florpyrauxifen-benzyl treatment on phytohormone transduction between florpyrauxifen-benzyl-resistant and -susceptible barnyard grasses (Echinochloa crus-galli (L.) P. Beauv). A total of 1810 DEGs were identified in the S comparison setting (FTS vs. UTS), and 915 DEGs were identified in the R comparison setting (FTR vs. UTR); 464 genes overlapped between the two comparison groups. Approximately sixty-nine hormone-related DEGs were detected after treatment with florpyrauxifen-benzyl in both R and S biotypes. At 24 h after florpyrauxifen-benzyl treatment, compared with the R biotype, the S biotype showed a stronger auxin response and higher expression of related genes involved in ethylene and abscisic acid biosynthesis and signal transduction. In addition, a brassinolide receptor gene was upregulated after florpyrauxifen-benzyl treatment and had higher expression in the S biotype than in the R biotype. This study is the first transcriptome analysis of the differential effects of florpyrauxifen-benzyl treatment between florpyrauxifen-benzyl-resistant and -susceptible E. crus-galli. It reflects the difference in phytohormone biosynthesis and signal transduction between R and S barnyard grasses in response to florpyrauxifen-benzyl treatment and will be helpful for understanding the phytotoxicity mechanisms of florpyrauxifen-benzyl. Full article
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13 pages, 2429 KiB  
Article
Candidate Genes Involved in Tolerance to Fenoxaprop-P-Ethyl in Rice Induced by Isoxadifen-Ethyl Hydrolysate
by Yaning Zhao, Wenqing Li, Lanlan Sun, Renhai Wu, Hongle Xu, Wangcang Su and Chuantao Lu
Agronomy 2023, 13(1), 225; https://doi.org/10.3390/agronomy13010225 - 11 Jan 2023
Cited by 2 | Viewed by 2076
Abstract
The metabolic resistance of plants to herbicides is similar to the herbicide metabolism process accelerated by safeners. The tolerance to fenoxaprop-P-ethyl (FE) is distinct among different varieties of rice in which phytotoxicity forms easily, resulting in the restricted use of FE in paddy. [...] Read more.
The metabolic resistance of plants to herbicides is similar to the herbicide metabolism process accelerated by safeners. The tolerance to fenoxaprop-P-ethyl (FE) is distinct among different varieties of rice in which phytotoxicity forms easily, resulting in the restricted use of FE in paddy. Safener effectively resolves this issue. This study showed that rice 9311 and Meixiangzhan No. 2 (MXZ) had different tolerance mechanisms to FE. Isoxadifen-ethyl hydrolysate (IH) alleviated FE the inhibition of rice growth. Transcriptome sequencing revealed numerous differentially expressed genes (DEGs) between the two varieties. A total of 31 metabolic enzyme genes related to herbicide detoxification were screened by analyzing the DEGs in different rice varieties or treatments. The results of the quantitative reverse transcription polymerase chain reaction indicated that 12 genes were potential metabolic genes resistant to FE in rice. Additionally, the enhanced expression of GSTU6, DIMBOA UGT BX8, and ABCG39 was confirmed to be induced by safener. Taken together, our results demonstrated that the induced expression of these three genes might be crucial for resistance to herbicide phytotoxicity in crops. These results may help us to understand herbicide metabolism in crops and to develop novel strategies for the safe use of herbicides. Full article
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