Fendioxypyracil, a new and systemic PPO-inhibiting herbicide for X-spectrum weed control

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15 Fendioxypyracil is a novel protoporphyrinogen oxidase (PPO)–inhibiting herbicide (HRAC 16 Group 14) developed to address the increasing prevalence of herbicide-resistant weeds and 17 to expand available weed control options. PPO inhibitors disrupt chlorophyll biosynthesis by 18 blocking the conversion of protoporphyrinogen IX to protoporphyrin IX, resulting in light-19 promoted formation of reactive oxygen species and rapid plant necrosis. Building on 20 established PPO chemistry, fendioxypyracil incorporates a pyridine-based core and an 21 aryloxy sidechain designed to enhance binding affinity and post-emergence activity. 22

23 Greenhouse evaluations demonstrated high efficacy of fendioxypyracil against key grass 24 weeds, including wild oat (Avena fatua), crabrass (Digitaria Sanginalis), goosegrass 25 (Eleusina indica) and barnyard grass (Echinochloa crus-galli), as well as strong control of 26 major broadleaf species. Physiological characterization and enzyme inhibition assays 27 confirmed PPO as the primary site and mode of action, with IC₅₀ values lower than those of 28 the commercial standard saflufenacil for both PPO isoforms. 29

30 Fendioxypyracil represents a next-generation PPO inhibitor with broad-spectrum and 31 systemic activity, offering a valuable new tool for integrated weed management. Its high 32 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 2 Internal biological activity and efficacy across multiple weed taxa supports its potential to enhance 33 on-farm weed control strategies and contributes to resistance management programs. 34 35 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 3 Internal 1. Introduction 36 37 Protoporphyrinogen oxidase (PPO) inhibitor herbicides – classified as Group 14 by the 38 Herbicide Resistance Committee (HRAC) – play a crucial role in modern weed management, 39 providing effective control of broadleaf and some grass weeds across diverse cropping 40 systems. These herbicides are valued for their rapid action, often producing visible 41 symptoms within hours under favorable environmental conditions (1). Their versatility allows 42 for both pre- and post-emergence applications, either as stand-alone products or in tank 43 mixtures, supporting both efficacy and resistance management strategies (2). 44 PPO inhibitors act by targeting two key enzymes in the tetrapyrrole biosynthetic pathway, 45 PPO 1 and 2, which are involved in the synthesis of chlorophyll and heme – two compounds 46 vital for plant survival. Inhibition of these enzymes disrupts the conversion of 47 protoporphyrinogen IX to protoporphyrin IX, leading to the accumulation of toxic 48 intermediates. Under light and aerobic conditions, this results in the strong generation of 49 reactive oxygen species (ROS), causing rapid membrane damage, tissue necrosis, and 50 ultimately plant death (3). 51 Several chemical families fall under PPO inhibitors, including diphenylethers (e.g., 52 fomesafen), N-phenyltriazolinones (e.g., sulfentrazone), and N-phenylimides (e.g., 53 saflufenacil (4)). Despite their structural diversity, these herbicides share a common mode of 54 action (MoA) and are widely used in crops such as soybean, corn, cotton, and cereals. Their 55 high efficacy, rapid symptom development, and relatively short environmental persistence 56 make them attractive for both conventional and conservation tillage systems. 57 Continuous innovation in PPO inhibiting chemistry has led to the discovery of new active 58 ingredients, even decades after the first introduction of nitrofen in 1964. Recent advances 59 include the development of molecules with improved characteristics, such as tiafenacil 60 (launched in 2020) (5). However, the emergence of herbicide resistance and the need for 61 broader-spectrum solutions drive ongoing research in this area (6, 7). 62 In response to these challenges, we introduce fendioxypyracil – provisionally approved by 63 ISO - a novel PPO inhibitor designed for broad-spectrum, post-emergence weed control in 64 major crops. Here, we present details on the discovery and synthesis, MoA confirmation, 65 and greenhouse efficacy of fendioxypyracil, highlighting its value as next-generation tool for 66 sustainable weed management (8). 67 68 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 4 Internal PPO herbicides generally provide strong dicot control both pre- and post-emergence (9). For 69 example, saflufenacil (Kixor®) is an excellent tool for post-emergence conyza control, one of 70 the most difficult dicot weeds to manage (10). Trifludimoxazin (Tirexor®) proved to be 71 exceptionally effective in controlling even PPO-resistant amaranth weeds (11). With the 72 horizon of PPO-tolerant crops in the midterm future and expected, as well as already 73 observed, resistance issues for Glyphosate on grass weeds (12, 13), we aimed to develop a 74 new post-emergence, broad-spectrum PPO herbicide – a crucial tool for future weed 75 management. 76 In the late 1990s, Novartis (now Syngenta) published PPO inhibitor herbicides bearing 77 pyridinone (Scheme 1, 1) as well as pyridine cores (2) (14-16). The pyridine motif was 78 further explored by the newly formed Syngenta company in the early 2000s, resulting in 79 pyrido-oxazinone (Scheme 1, 3) and 3-arylpyridine structures (4) (17-19). None of these 80 structures were commercialized, and the central pyridine motif in PPO structures did not 81 receive further attention until BASF revisited it in 2017 (8). By employing nucleophilic 82 aromatic substitution (SNAr) reactions, diverse nucleophiles can be readily introduced onto 83 the pyridine core. Even complete warheads bearing a nucleophilic nitrogen can be directly 84 attached (20). Besides warheads, sidechains connected via nucleophilic atoms like oxygen 85 can be easily introduced. For PPO herbicides, ether sidechains proved to be highly active, 86 ranging from simple methoxy- or propargyloxy-ethers to lactic acid- and acetal-sidechains (9, 87 21). Another interesting class of ether sidechains includes substituted aryloxy residues. In 88 the early 2000s, Sumitomo described a set of phenoxy-, pyridyloxy-, and pyrimidyloxy-89 sidechains with diverse substitutions in the ortho-, meta-, or para-positions (22, 23). 90 Sumitomo’s work on aryloxy sidechains ultimately led to the PPO market product 91 Epyrifenacil (Rapidicil®) (24), which features a pyridyl-ether sidechain and a phenyl core. 92 Connected through SNAr reactions, the aryloxy side chains are particularly intriguing when 93 combined with the pyridine core. The preferred dihedral angle between the PPO core and 94 the aryloxy side chain is more constrained with a pyridine core compared to a phenyl core 95 (Figure 1). This pyridine core induced preorganization matches the ligand’s dihedral angle in 96 the enzyme pocket more closely, thereby promoting a favorable fit with the targeted binding-97 mode geometry. While, in general, ortho-, meta-, and para-substituted phenoxy as well as 98 pyridyloxy residues show good biological activity in combination with the pyridine core (19), a 99 simple catechol unit elongated by ethyl acetate provided excellent grass and dicot control 100 post-emergence. This led to the invention of compound 5, provisionally approved by ISO as 101 fendioxypyracil, BASF’s next-generation herbicide for post-emergence broad-spectrum weed 102 control (Scheme 1, 5). Here, we present evidence for the high efficacy of fendoxypyracil and 103 the mode and site of action of fendioxypyracil. 104 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 5 Internal 105 106 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 6 Internal 2. Material and Methods 107 108 2.1 Statistical distribution of dihedral angle in Figure 1 109 The histogram of the statistical distribution of dihedral angles was generated with the 110 software MOE (25). 111 The data were obtained from the Mogul program (CSD 6.00 with CSD Aug25 update) of the 112 CCDC suite (26). 113 The analyzed dihedral angles were C–C–O–C for the phenyl variant and N–C–O–C for the 114 pyridine variant. 115 2.2 Synthetic Method 116 2.2.1 Synthesis of Fendioxypyracil (5) 117 Step (a): 2-azido-6-(2-benzyloxyphenoxy)-5-chloro-3-fluoro-pyridine (7) 118 To a solution of 5.0 g (29 mmol) 3-chloro-2,5,6-trifluoropyridine (CAS 2879-42-7) in 50 mL 119 DMSO was added 2.1 g (33 mmol) NaN3 and the solution was stirred at room temperature 120 for 3 hours. Then 19.5 g (60 mmol) Cs2CO3 was added followed by a solution of 6.2 g (31 121 mmol) 2-(Benzyloxy)phenol) in 40 mL DMSO. The mixture was stirred at room temperature 122 for 16 hours, water (200 mL) was added and the mixture was extracted with ethyl acetate 123 (3*300 mL). The organic layer was separated, washed with brine, dried over anhydrous 124 Na2SO4, filtered and the solvent was removed under reduced pressure. The crude material 125 (15 g) was used without further purifiction in the next step. [M+H] = 371.0; Rt = 1.368 min 126 Step (b): 2-amino-6-(2-benzyloxyphenoxy)-5-chloro-3-fluoro-pyridine 127 To a solution of 15 g of compound 7 in THF (100 mL) was added 9.7 g (150 mmol) zinc and 128 100 mL aq. NH 4Cl dropwised at 0°C. The mixture was stirred for 16 hours at room 129 temperature, filtered and the filter cake was wa shed with ethyl acetate (50 mL). The filtrate 130 was extracted with ethyl acetate (3*200 mL), the combined organic layer was dried over 131 anhydrous Na 2SO4, filtered and the solvent was removed under reduced pressure. The 132 crude material was purified by silica gel column (petrol ether/ethyl acetate) to give 8.8 g 133 (25.6 mmol, 88% from 3-chloro-2,5,6-trifluoropyridine) of 2-amino-6-(2-benzyloxyphenoxy)-5-134 chloro-3-fluoro-pyridine. [M+H] = 345.0; Rt = 1.232 min 135 Step (c): ethyl N-[6-(2-benzyloxyphenoxy)-5-chloro-3-fluoro-2-pyridyl]carbamate (8) 136 To a solution of 8.8 g (25.6 mmol) of 2- amino-6-(2-benzyloxyphenoxy)-5-chloro-3-fluoro-137 pyridine in 80 ml dichloromethane was added 3 g (38 mmol) pyridine followed by 4 g (37.5 138 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 7 Internal mmol) ethyl chloroformate. The mixture was stirred at 25°C for 20 hours, diluted with water 139 and extracted with dichloromethane. The combined organic layer was washed with brine, 140 dried over anhydrous Na 2SO4 and concentrated to give 14.4 g of a mixture of carbamate 8 141 and the di-substituted derivative. The crude mi xture (12.4 g) was dissolved in 200 ml ethanol 142 and aqueous NaOH (1 M) was added dropwise at 0° C with stirring. The mixture was stirred 143 at 15°C for 6 hours, diluted with brine and extracted with ethyl acetate. The combined 144 organic layer was dried over anhydrous Na2SO4, filtered and the solvent was removed under 145 reduced pressure. The crude product was purified by column chromatography on silica 146 (petrol ether/ethyl acetate) to give 6.6 g (15.9 mmol, 62%) of the desired compound 8. [M+H] 147 = 417.1; Rt = 1.293 min 148 Step (d): 3-[6-(2-benzyloxyphenoxy)-5-chloro-3-fluoro-2-pyridyl]- 6-(trifluoromethyl)-1H-149 pyrimidine-2,.4-dione 150 To a solution of 1.7 g (43 mmol) NaH in NMP (60 mL) at 0°C was added 6 g (14 mmol) of 151 compound 8 and the mixture was stirred for 30 minutes at 35°C. Then 3.9 g (21 mmol) of 152 ethyl (E)-3-amino-4,4,4-trifluoro-but-2- enoate (CAS: 372-29-2) was added and the reaction 153 mixture was stirred at 100°C for 3 days. The resulting mixture was quenched with ice water 154 (100mL), acidified to pH=2 by using 6N HCl and extracted with ethyl acetate (3*100mL). The 155 combined organic layer was washed with brine, dried over anhydrous Na 2SO4, concentrated 156 and directly used in the next step. [M+H] = 508.0; Rt = 1.240 min 157 Step (e): 3-[6-(2-benzyloxyphenoxy)-5-chloro-3-fluoro-2-pyridyl]-1-methyl-6-(trifluoromethyl)- 158 pyrimidine-2,4-dione (9) 159 To a solution of 6.5 g (12.8 mmol) of 3-[6-(2-benzyloxyphenoxy)-5-chloro-3-fluoro-2-pyridyl]-160 1-methyl-6-(trifluoromethyl)-pyrimidine-2,.4-dione in 65 mL acetonitrile was added 5.3 g (38 161 mmol) K2CO3 followed by 7.3 g (51 mmol) methy iodide at 0 o C with stirring. The mixture 162 was stirred at 15°C for 16 hours, then water (80 mL) was added, and the pH was adjusted to 163 pH=5 by using 2M HCl. The mixture was extracted with ethyl acetate (3*90mL), the 164 combined organic layer was washed with brine and dried over anhydrous Na 2SO4, filtered 165 and the solvent was removed under reduced pressure yielding 7 g of the crude product 9, 166 which was used without further purification. 167 1H-NMR (CDCl3, ppm): 7.63 (d, J=7.28 Hz, 1 H); 7.21 - 7.25 (m, 4 H); 7.12 - 7.17 (m, 2 H); 168 6.98 (t, J=7.03 Hz, 3 H); 6.26 (s, 1 H); 4.99 (s, 2 H); 3.47 (s, 3 H). [M+H] = 522.0; Rt = 1.323 169 min 170 Step (f): 3-[5-chloro-3-fluoro-6-(2-hydroxyphenox y)-2-pyridyl]-1-methyl-6-(trifluoromethyl) 171 pyrimidine-2,4-dione 172 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 8 Internal To a solution of 7 g (13.4 mmol) of compound 9 in 70 mL xylene was added 3.6 g (26 mmol) 173 solid AlCl 3 at 15°C with stirring. The mixture was stirred at 130 o C for 16 hours and after 174 cooling to 15°C, ice-water (100 mL) was added to the mixture. After separation of the xylene 175 layer, the water phase was extracted with ethyl acetate (3*80 mL), the combined organic 176 layer was dried over anhydrous Na 2SO4, filtered and the solvent was removed under 177 reduced pressure. The crude product was purified by column chromatography on silica gel 178 (petrol ether/ethyl acetate) to give 3.2g (7 .4 mmol, 55%) of 3-[5-chloro-3-fluoro-6-(2-179 hydroxyphenoxy)-2-pyridyl]-1-methyl-6-(trifluoromethyl)-pyrimidine-2,4-dione. 180 1H-NMR (CDCl3, ppm): 7.80 (d, J=7.26 Hz, 1H); 7.03 – 7.19 (m, 3H); 6.93 (dt, J=7.68 Hz, 181 J=1.7 Hz, 1H); 6.3 (s, 1H); 5.6 (s, 1H); 3.5 (s, 3H).[M+H] = 431.9; Rt = 1.077 min 182 Step (g): ethyl 2-[2-[[3-chloro-5-fluoro-6-[3-methyl-2,6-dioxo-4-(trifluoromethyl)pyrimidin-1-yl]-183 2-pyridyl]oxy]phenoxy]acetate, Fendioxypyracil, (5) 184 To a solution of 0.2 g (0.46 mmol) of 3-[5-c hloro-3-fluoro-6-(2-hydroxyphenoxy)-2-pyridyl]-1-185 methyl-6-(trifluoromethyl)-pyrimidine-2,4-dione in 10 mL dry acetonitrile was added 0.19 g 186 (1.3 mmol) K 2CO3 at 0 oC followed by dropwise addition of 0.15 g (0.92 mmol) ethyl 187 bromoacetate. The mixture was stirred at 15° C for 16 hours, diluted with 15 ml water and 188 extracted with ethyl acetate (3*15mL). The combined organic layer was washed with brine, 189 dried over anhydrous Na 2SO4, filtered and the solvent was removed under reduced 190 pressure. The crude product was purified by reversed phase preparative HPLC containing 191 TFA to give 0.16 g (0.31 mmol, 67%) of ethyl 2-[2-[[3-chloro-5-fluoro-6-[3-methyl-2,6-dioxo-192 4-(trifluoromethyl)pyrimidin-1-yl]-2-pyridyl]oxy]phenoxy]acetate (5, Fendioxypyracil). 193 1H-NMR (CDCl3, ppm): 7.76 (d, J=7.28 Hz, 1 H); 7.22 (d, J=7.72 Hz, 1 H); 7.17 (t, J=7.83 194 Hz, 1 H); 6.99 - 7.06 (m, 1 H); 6.88 (d, J=7.94 Hz, 1 H); 6.25 (s, 1 H); 4.49 (s, 2 H); 4.19 (q, 195 J=7.20 Hz, 2 H); 3.47 (s, 3 H); 1.25 (t, J=7.17 Hz, 3 H). [M+H] = 518.0; Rt = 1.217 min 196 197 2.3 Biochemistry test Methods 198 2.3.1 Recombinant Expression, Purification, and In Vitro Inhibition Assays of wild type 199 Amaranthus tuberculatus PPO1 and PPO2 enzymes. 200 The complete coding sequences of wild-type Amaranthus tuberculatus PPO1 and PPO2 201 were synthesized de novo and inserted into the pRSetB expression vector (Invitrogen, 202 Carlsbad, CA, USA) using BamHI and HindIII rest riction sites. To facilitate purification, an N-203 terminal hexahistidine tag was included. Recombinant constructs were transformed into 204 Escherichia coli strain BL21(DE3)pLysS (Novagen, EMD Millipore, Billerica, MA, USA), and 205 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 9 Internal transformants were selected on LB agar plates containing 100 µg mL ⁻ ¹ ampicillin and 34 µg 206 mL⁻ ¹ chloramphenicol. 207 For protein expression, a single colony was inoculated into 3 mL LB medium with antibiotics 208 and incubated at 37 °C with shaking (200 rpm) for 6 h. A 20-µL aliquot of this starter culture 209 was transferred into 20 mL fresh LB medium and grown overnight. The following day, 100 µL 210 of the overnight culture was inoculated into 100 mL ZYM-5052 autoinduction medium 211 supplemented with antibiotics. Cultures were incubated at 37 °C for 5 h and then shifted to 212 25 °C for an additional 21 h. 213 Cells were collected by centrifugation at 6,000 × g for 30 min at 4 °C. Pellets were 214 resuspended in PPO lysis buffer [10 mL g ⁻ ¹ pellet; 50 mM NaH ₂ PO₄ , 100 mM NaCl, 5 mM 215 imidazole, 5% (v/v) glycerol, pH 7.5] supplemented with 20 mg mL ⁻ ¹ lysozyme, 30 U mL ⁻ ¹ 216 DNase I, and protease inhibi tors (complete EDTA-free, Roche Diagnostics, Mannheim, 217 Germany). Suspensions were sonicated on ice (3 min total, 30 s bursts at 90% amplitude). 218 After centrifugation at 38,000 × g for 30 min at 4 °C, the supernatant was collected and 219 supplemented with 2 mL of 5 M NaCl. 220 For affinity purification, a 500-µL bed volume of HisPur Ni-NTA resin (Thermo Fisher 221 Scientific, IL, USA) was equilibrated with buffer (20 mM NaH ₂ PO₄ , 50 mM NaCl, 5 mM 222 imidazole, 5 mM MgCl ₂ , 17% glycerol, 0.1 mM EDTA, pH 8.0). The clarified extract was 223 applied to the resin, which was then washed with 5.6 mL wash buffer (20 mM NaH ₂ PO₄ , 50 224 mM NaCl, 5 mM imidazole, 17% glycerol, pH 7.5). Bound proteins were eluted with 1 mL 225 elution buffer (20 mM NaH ₂ PO₄ , 50 mM NaCl, 250 mM imidazole, 17% glycerol, pH 7.5). 226 Protein concentrations were measured us ing a Scandrop nano volume spectrophotometer 227 (Analytikjena, Life Science, Germany). Purity and solubility were confirmed by SDS–PAGE 228 (10%) with 2.5 µg protein per lane. 229 Enzyme activity assays for PPO1 and PPO2 were performed using a fluorescence-based 230 approach (excitation 405 nm, emission 630 nm). Reactions (187 µL) contained 100 mM 231 Tris–HCl, 1 mM EDTA, 5 mM DTT, 0.0085% Tween 80, and 15 µL enzyme in resuspension 232 buffer (50 mM Tris–HCl, pH 7.3, 3.2 mM EDTA, 20% v/v glycerol). Enzyme concentrations 233 were adjusted for each variant to normalize maximum fluorescence in the absence of 234 inhibitor under saturating substrate conditions. 235 Dose–response assays were carried out with f endioxypyracil and saflufenacil, dissolved in 236 80% DMSO. Ten concentrations (10 µL; 1 × 10 ⁻ /i1 to 5.12 × 10 ⁻ ¹² M) were tested in the 237 assay mixture, with a 30-min pre-incubati on at room temperature before addition of 238 protoporphyrinogen IX. Fluorescence was monitored for 30.25 min (33 cycles of 55 s each) 239 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 10 Internal using a CLARIOstar microplate reader (BMG LabTech, Germany). Percent inhibition was 240 calculated relative to untreated (positive) and no-enzyme (negative) controls. All assays 241 were performed in triplicate. IC ₅₀ values (inhibitor concentrati on reducing PPO activity by 242 50%) were estimated by nonlinear regression usin g three- or four-parameter log-logistic 243 models. 244 2.3.2 Physiological Profile 245 Generation of the physiological profiles were performed exactly as described in Johnen et 246 al., 2022 (27). 247 2.3.2.1 Cell Galium 248 Freely suspended callus from Galium mollugo was heterotrophically cultivated in a modified 249 Murashige-Skoog Medium (4.4g/L M&S basal medium, 30g/L sucrose, 29.7mg/L L-alanine, 250 3.1mg/L L-arginine-monohydrochloride, 3.8mg/L L-asparagine, 1.7mg/L L-aspartic acid, 26 251 mg/L gamma-aminobutyric acid, 3 mg/L L-cysteine, 0.3mg/L L-glutamine, 15.7 mg/L L-252 glutamic acid, 2.7mg glycine, 0.05 mg/L L-histidine-monohydrochloride, 5 mg/L L-leucine, 2 253 mg/L L-lysine hydrochloride, 0.05 mg/L DL-methionine, 0.05 mg/L DL-phenylalanine, 1.9 254 mg/L L-proline, 12.8 mg/L L-serine, 4.1 mg/L DL-threonine, 0.05 mg/L L-tyrosine, 2.3 mg/L 255 DL-valine, 2 mg IAA, 0.1mg 2,4-D). The cells were subcultured in 7-day intervals. For 256 screening, acetone solutions of the test compounds were pipetted into plastic tubes, and the 257 solvent was allowed to evaporate before adding 2 mL of exponentially growing cell 258 suspension. The tubes were shaken at 400 rpm and 25°C in the dark on a rotary shaker with 259 an attachment for 288 test tubes. After incubation for eight days, the conductivity of the 260 growth medium was measured using a micro-electrode (Mettler Toledo FiveEasyPlus with 261 the electrode InoLab-752). The mean of three replicates was determined and subtracted 262 from the value obtained before incubation. The reduction in conductivity is inversely 263 proportional to the increase in growth. Results were expressed as percentage growth 264 inhibition relative to untreated control. 265 2.3.2.2 Algae 266 Cells of Scenedesmus acutus (culture collection Gottingen, 276-3a) were propagated 267 photoautotrophically in aerated culture tubes containing an inorganic medium (1 g/L 268 potassium nitrate, 260 mg/L disodiumhydrogenphosphat dihydrate, 740 mg/L potassium 269 dihydrogen phosphate, 2.55 g/L magnesium sulfate heptahydrate, 25 mg/L calcium chloride 270 hexahydrate, 0.0066 mg/L aluminum sulfate octadecahydrate, 0.099 mg/L manganese 271 chloride tetrahydrate, 0.005 mg/L copper sulfate pentahydrate, 0.028 mg/L cobalt sulfate 272 pentrahydrate, 0.0063 mg/L zinc sulphate heptahydrate, 0.03 mg/L boric acid, 0.002 mg/L 273 ammonium molybdate tetrahydrate, 0.0029 mg/L Ammonium metavanadate, 0.026 mg/L 274 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 11 Internal Nickel(II) sulphate hexahydrate, 0.25 mg/L potassium iodide, 0.24 mg/L potassium bromide, 275 0.0084 mg/L potassium bromide, 14.5 mg/L iron(III) nitrate nonahydrate, 13.3 mg/L 276 Titriplex® III, 0.048 mg/L copper sulfate pentahydrate) and kept at 22°C under continuous 277 light (Thorn white neon tubes, c.90 pmol m-z s-l, 400-750 nm). The bioassay was performed 278 in plastic microtiter dishes (8.5 x 12.5 cm, NUNC) containing 24 wells. Before loading the 279 wells with 1 mL cell suspension each, the test compounds were added in acetone, and the 280 solvent was allowed to evaporate. The 15 additional compartments of the dishes were filled 281 with sodium carbonate/bicarbonate buffer (0.5 ml) generating a 0.25 % partial pressure of 282 carbon dioxide. The dishes were sealed with plastic lids and incubated on a MTS 4 shaker 283 (IKA, Staufen, Germany) at 500 rpm under continuous light (Osram white neon tubes, c.70 284 pmol m-' s-l, 400-750 nm) at 23°C. After 24 h, the contents of each well were removed, 285 diluted and cell numbers were determined by a Coulter Counter (type ZM, Coulter 286 Electronics, Luton, UK). Two replicates were measured, and growth inhibition was calculated 287 as a percentage of the control. 288 2.3.2.3 Lemna 289 For L. paucicostata cultivation and treatments, stock cultures were propagated 290 mixotrophically in an inorganic medium containing 1 % (w/v) sucrose (KNO3 (400 mg/L), 291 CaCl2 * 2 H2O (540 mg/L), MgSO4 * 7 H2O (614 mg/L), KH2PO4 (200 mg/L), Fetrilon 13 % 292 (2,81 mg/L), MnCl2 * 4 H2O (0.415 mg/L), H3BO3 (0.5 mg/L), Na2MoO4 * 2 H2O (0.12 mg/L), 293 ZnSO4 * 7 H2O (0.05 mg/L), CuSO4 * 5 H2O (0.025 mg/L) and CoCl2 (0.025 mg/L). The 294 bioassay was conducted under aseptic conditions in plastic petri dishes (5 cm in diameter), 295 which contained 15 mL medium without sucrose. The test compounds were added to the 296 dishes in acetone solution, and the organic solvent was allowed to volatilize before four 297 fronds were added to each dish (4 leaves per dishes). The culture dishes were then closed 298 with plastic lids and incubated under continuous light (white LED irradiation, 70 µmol m-2 s-1) 299 in a growth chamber at 25°C. Eight days after treatment, the increase of the area covered by 300 the fronds in each dish was determined as the growth parameter using an image analyzing 301 system (LemnaTec Scanalyzer; LemnaTec, Würselen, Germany). The area of fronds before 302 incubation was subtracted from this value. Results were expressed as percentage growth 303 inhibition relative to untreated control. 304 2.3.2.4 Arabidopsis 305 Sterilized seeds (MC24 ecotype) were stratified overnight at 4°C in 48-well plates containing 306 250 µL half-strength Murashige & Skoog incl. Gamborgs B5 Vitamins (Duchefa: 307 M0231.0050; 2,2 g /1 L) containing 2.5 µL of acetone (as solvent control) or 2.5 µL 308 respective compound resulting in the following concentrations 0.001, 0.01 and 0.1 mM. 48-309 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 12 Internal well plates were sealed with micropore tape and grown for 7 d in constant light at 22 °C 75% 310 humidity. Growth inhibition and symptoms were evaluated manually. 311 2.3.2.5 Cress germ. D and Cress germ. L 312 For the germination bioassay, seeds of cress (Lepidum sativum L) were placed in 6-well 313 plates filled with a vermiculite substrate. Stock solutions of the test compounds in acetone 314 were added together with 12 mL of water to reach respective test concentrations. Control 315 seeds were moistened only with water and acetone. The plates were incubated in a growth 316 chamber at 22 °C in the dark for 72 h. Inhibition of germination and seedling development 317 was evaluated visually (0 = no influence, 100 = total inhibition). Afterwards, the dishes were 318 incubated for further 3 days under light conditions (16h/8 h light:dark at 22 °C and 75% 319 relative humidity, 230 µmol m−2 s−1 photon irradiance, 400–750 nm) and seedling 320 development and plant symptoms were evaluated. 321 2.3.2.6 Hill Assay 322 Thylakoids were isolated from shoots of 3 weeks-old plants of Triticum aestivum L, as 323 follows. Plants were put 24 h in dark and subsequent steps were performed under green 324 light. Shoots were cut and homogenized in Hill-Medium (HM) containing 50 mM tricine, 10 325 mM NaCl, 5 mM MgSO4 and 0.4 M sucrose (pH 8.0 adjusted with NaOH) using a mixer. 326 Homogenate was filtered and centrifuged at 500 x g. Pellet was washed with suspension 327 medium (SM) containing 50 mM tricine, 10 mM NaCl and 5 mM MgSO4 (pH 8.0 adjusted 328 with NaOH) once at 500 x g and resuspended in reaction medium (RM) containing 50 mM 329 tricine, 5 mM MgSO4 and 0.1 M sucrose (pH 8.0 adjusted with NaOH). For the Hill assay, 330 isolated thylakoids (chlorophyll content 41 µg ml−1) in reaction medium were used. The 331 influence of the compounds on photosynthetic electron transport in photosystem II was 332 evaluated according to the method of Avron and Shavit (28). Briefly, the assay mixture 333 consisted of thylakoid suspension (0.23 ml), test compound dissolved in 80% aqueous 334 acetone + water (80 + 20 by volume; 0.05 ml), and K-ferricyanide (0.02 ml) with and without 335 compound. During the subsequent illumination, ferrocyanide was formed in the Hill reaction 336 if not inhibited by compound present. Then, in darkness, the ferrocyanide was allowed to 337 react with ferric salt to form the ferrous salt which produced a complex with phenanthroline. 338 The complex was measured photometrically by its absorption at 510 nm. Results were 339 expressed as percent inhibition relative to untreated control and after subtraction of 340 absorbance of the compound itself. 341 2.3.2.7 CO2 assimilation 342 The plants of Galium aparine L, which had been raised under greenhouse conditions to the 343 second-whorl stage, were cultivated in Vermiculite containing pots watered with half 344 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 13 Internal Linsmaier Skoog medium (KNO3 950 mg/L, NH4NO3 825 mg/L, MgSO4*7H2O 185 mg/L, 345 CaCl2*2H2O 219 mg/L, KH2PO4 85 mg/L, Fetrilon 13 % 46.2 mg/L, H3BO3 3 mg/L, 346 MnSO4*H2O 6.8 mg/L, ZnSO4*7H2O 5.3 mg/L, KJ 0.42 mg/L. Na2MoO4*2H2O 0.125 mg/L, 347 CuSO4*5H2O 0.015 mg//L, CoCl2*6H2O 0.015mg/L, pH 5.8) for 5 days in a Phytotron 348 chamber (12h day/ 12h night for 25°C / 22°C, 75% humidity). The plant treatment is a foliar 349 spray application of a compound with the concentration of 10-3M. The measurement of the 350 photosynthetic rate (µmol (CO2) m-2 s-1) to determine the inhibition was accomplished with a 351 LI-COR, LI-6400XT, comparing the untreated Galium plant at timepoint 0h with the same 352 plant 1 day after the compound application (24h). Additionally, epinasty and necrosis 353 symptoms are evaluated visually. Results were expressed as percent inhibition relative to 354 untreated control. 355 2.3.2.8 Respiration 356 Galium mollugo were cultivated as described in Cell Galium (see point 1.1). 3 mL Galium cell 357 suspensions were treated with compound in plastic tubes for 3-5 h in the dark on a rotary 358 shaker. Measurement of oxygen consumption using the dissolved oxygen measuring system 359 Mettler Toledo SevenExcellence. After 30 s of calibration the oxygen consumption (mg/L) in 360 a time frame of 60 s was determined. The resulting consumption was used to calculate the 361 inhibition of oxygen consumption relative to the mock treated control. 362 2.3.2.9 Uncoupler 363 50 mL BY-2 suspension culture cells (7-9 days old) heterotrophically grown in Linsmaier & 364 Skoog medium supplemented with 3 % (w/v) sucrose and 200 µg/L 2,4-D were pelleted by 365 gravity and resuspended in 50 mL suspension buffer (50 mM HEPES, 0.5 mM CaCl2, 0.5 366 mM K2SO4, 10 mM Glucose, pH of 7.0 with KOH). 2 mL of cell suspension was treated with 367 the respective compound in respective concentration in Greiner tubes and incubated for 1.5 368 h at 25°C in the dark while shaking (300 rpm). Cells were washed with suspension buffer. 369 750 µL cell suspension was incubated with 2 µg/µL JC-1 Dye in 24-well plates (Thermo 370 Fisher, T3168) for 15 min in the dark while shaking. JC-1 exhibits potential-dependent 371 accumulation in mitochondria, indicated by a fluorescence emission shift from green to red 372 (29). Fluorescence emission at 590 nm at an excitation at 500 nm was measured using a 373 plate fluorometer. Inhibition value is calculated as follows: fluorescence intensitymock ctrl – 374 fluorescence intensitytest compound /fluorescence intensitymock control – fluorescence intensitypositive 375 ctrl (dinoseb). Samples were measured in duplicates. 376 2.3.2.10 ROS Assay 377 To determine the formation of reactive oxygen species (ROS), Lemna plants grown 7 to 9 378 days according to point 1.3 were treated with respective compounds and mock for 18 h and 379 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 14 Internal then stained with 10 μ M of dihydroethidium (DHE) in 100 μ M of CaCl2, pH 4.75, while 380 shaking for 30 min at room temperature in the dark according to (30). DHE is a superoxide 381 anion specific indicator that is oxidized by ROS to yield fluorescent 2-hydroxyethidium. After 382 soaking in 100 μ M of CaCl2 for 5 min to remove the residual dye, fluorescence of 2-383 hydroxyethidium in Lemna roots was observed using an Olympus BX61 epifluorescence 384 microscope (Hamburg, Germany). ROS formation was evaluated visually (0 = no formation, 385 100 = strong formation). 386 2.3.2.11 Chlorophyll fluo. 387 For L. paucicostata cultivation and treatments, stock cultures were propagated 388 mixotrophically in an inorganic medium containing 1 % (w/v) sucrose (KNO3 (400 mg/L), 389 CaCl2 * 2 H2O (540 mg/L), MgSO4 * 7 H2O (614 mg/L), KH2PO4 (200 mg/L), Fetrilon 13 % 390 (2,81 mg/L), MnCl2 * 4 H2O (0.415 mg/L), H3BO3 (0.5 mg/L), Na2MoO4 * 2 H2O (0.12 mg/L), 391 ZnSO4 * 7 H2O (0.05 mg/L), CuSO4 * 5 H2O (0.025 mg/L) and CoCl2 (0.025 mg/L)). The 392 bioassay was conducted under aseptic conditions, using 15 mL medium without sucrose. 393 The bioassay was performed in plastic microtiter dishes (8.5 x 12.5 cm, NUNC) with 24 394 wells. Loading the wells with 1 mL cell suspension and approx. 12 fronds of Lemna. Effects 395 on chlorophyll fluorescence (fluorescence quantum yield, Y(II)) were measured after 24 h 396 compound treatment using an Imaging Pulse-Amplitude-Modulation (PAM) M-Series system 397 (Walz, Effeltrich, Germany). Measurements were taken after 5 minutes of darkness with the 398 following settings: Meas.light=1, act. Light=2. Results were expressed as percent inhibition 399 relative to untreated control. 400 2.3.2.12 ATP content 401 Growth and treatment were performed according to Chlorophyll fluorescence (point 1.11). 402 ATP content was measured with the ATP Determination Kit (A22066, Thermo Fisher 403 Scientific,Grand Island, NY14072) according to manufacturer’s instructions using 9-12 mg L. 404 paucicostata extract in tricine buffer. Results were expressed as percentage growth 405 inhibition relative to untreated control and fresh weight. 406 2.3.2.13 Neural Network Modeling of Physiological Profiling Data 407 A variational autoencoder was fitted to the results of 14 types of physiological assays for 408 herbicide compounds which were assessed at different concentrations as described in 409 Johnen et al., 2022 (10.1002/ps.7004). Concentrations were treated as different features, 410 resulting in a total of 34 features. Samples per compound/assay/concentration combinations 411 were aggregated by median. The autoencoder was semi-supervised with a classification 412 network attached to the latent samples and learned a latent space with eight dimensions. 413 Multilabel classification was applied to allow for non-mutually exclusive MoA predictions. 414 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 15 Internal Eight classes of modes of action, along with an 'Unknown Mode of Action' class were used 415 as targets. Monte-Carlo dropout was applied in the classification network. The uncertainty 416 resulting from the samples in latent space along with the Monte-Carlo dropout samples of 417 the classification network allowed for assessments of uncertainty of predicted MoA labels. 418

sample contributions to the cross entropies MoA class were inversely weighted 419 by the number of positive examples over negative examples, for their respective MoA 420 classes. Missing values for input features and labels were imputed with zeros but were 421 masked in the respective loss function terms. The Kullback-Leibler Divergence (KLD) and 422 classification loss terms were balanced using weight parameters in the loss function. The 423 KLD and classification weights were slowly ramped up during training, to help the learning. 424 The test compound fendioxypyracil was part of the test set of unknown mode-of-actions. 425 426 2.4 Herbicidal Test Methods 427 2.4.1 POST- Emergence Greenhouse Trials 428 The active ingredients for the POST-Emergenc e greenhouse trials were selected from the 429 most used PPO inhibitors (HRAC E, 14) in US and Brazil Soy fields: saflufenacil (N-Phenyl-430 imide, manufacturer: BASF), trifludimoxazin (N-Phenyl-imide, BASF), tiafenacil (N-Phenyl-431 imide, Nufarm), Flumioxazin (N-Phenyl-imide, Sumitomo). 432 The key broadleaf weed species and the grass species that were tested in the greenhouse 433 trials are described in Table 1, including the EPPO Codes (former Bayer Codes, European 434 and Mediterranean Plant Protection Organization). All used seeds are an own production in 435 BASF’s Germany site at Limburgerhof. Application was done at BBCH 12/13. 436 The plants were cultivated using standard methods in Limburgerhof soil (slightly loamy sand 437 soil, clay 6,9% dm; loam 16,6% dm; sand 76,5% dm, organic matter (OM) 1,38% dm; pH 438 7,4). The plant pots had a diameter of 9 cm at the broadest point and contained 439 approximately 313 cm3 of soil (standard pot size). Monocot weeds were cultivated directly in 440 the plant pots. Dicot weeds were cultivated in propagation soil (pH 5,6; N 14%, P 2O5 16%, 441 K2O 18%, Fe 0,09%) and transplanted into pots with Limburgerhof soil after emergence. 442 The plants were treated with specific formulated active ingredients at various application 443 rates to evaluate their responses to different dosages. The application was carried out under 444 controlled conditions to facilitate a clear distinction between the active compounds and to 445 manage the various weed species effectively. An initial trial aimed to establish suitable 446 application rates. Given that most of the compounds are UV-dependent, significantly lower 447 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 16 Internal rates were employed in greenhouse trials compared to field rates. For consistency, all PPO 448 inhibitors were applied at a uniform rate (Table 2). 449 The POST-Emergence trial was repeated 4 times in terms of having enough replication for 450 each evaluation of each rate. The application volume was standardized at 200 liters per 451 hectare, with 0.5% methylated seed oil (MSO) used as an adjuvant. All applications were 452 conducted using a flat spray nozzle from the XR Teejet 110015VS series. After treatment, 453 the solvents and water were allowed to evaporate from the plants for 30 minutes in a 454 separate tunnel with an airflow of 3000 m-3 h. Subsequently, the plants were transferred to 455 greenhouses tailored to the required growing conditions. The trials utilized three different 456 greenhouses: a warm house (22-24°C, mean humidity 57%), a cold house (18-21°C, mean 457 humidity 64%), and a cold cabin (12-14°C, mean humidity 83%). Each greenhouse was 458 illuminated with photosynthetically active radiation (PAR; 380 – 780 nm) from 10:00 p.m. to 459 4:00 a.m., in addition to natural daylight. 460 Irrigation for the plants was conducted using specially prepared water that included nutrients 461 tailored to their growth stage, biomass availability, and water needs. The irrigation water was 462 prepared by diluting 1 per mile of the liquid fertilizer "Kamasol brilliant Grün 10-4-7®" in tap 463 water. 464 Plant damage was assessed at 7- and 20-days post-application of the active ingredients. 465 The evaluation involved a visual inspection of the above-ground parts of the plants, with 466 damage quantified as a percentage of Plant Damage Compared to Untreated Control 467 (PDCU) using a scale ranging from 0 to 100, including increments of 2 (0%, 5%, 10%, 15%, 468 …, 90%, 95%, 98%, 100%). A PDCU value of 0% indicated no damage, while 100% 469 indicated complete plant death. For the analysis of the rating data collected, the statistical 470 software R was utilized. The analysis of variance (ANOVA) technique, as outlined by Stahle 471 and Wold in 1989, was employed to identify differences in means. When significant 472 differences were noted in the ANOVA results, the means were categorized into distinct 473 groups following the method described by Scott and Knott, using a significance level (α ) of 474 0.05. The clustering analysis method developed by A. Scott and M. Knott (31) was applied to 475 group the variants into cohesive and homogeneous categories. 476 477 3. Results and discussion 478 479 3.1 Synthesis 480 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 17 Internal Fendioxypyracil can be synthesized starting from 3-chloro-2,5,6-trifluoropyridine (Scheme 2). 481 In a sequential one-pot nucleophilic substitution reaction using sodium azide followed by 2-482 (benzyloxy)phenol, the respective aryl-ether azide is formed. Reduction of the azide to the 483 amine using zinc and subsequent reaction with ethyl chloroformate generates the respective 484 carbamate building block 8. From the carbamate the uracil ring is constructed by employing 485 ethyl 3-amino-trifluorobutenoate followed by N-methylation. Deprotection of the benzyl-group 486 and alkylation with ethyl bromoacetate provides then fendioxypyracil (5) with very good 487 yields. 488 489 3.2 Physiological profiling of fendioxypyracil indicates inhibition of PPOs as MoA 490 Physiological profiling for the identification of herbicidal modes of action has been 491 successfully used and refined for decades (30, (27, 32). The MoA identification is based on 492 the generation of an inhibition fingerprint from an array of different assays that also includes 493 the assessment of the compound-induced symptoms. To identify its mode of action, we 494 generated a physiological profile (P-Profile) for fendioxypyracil (Fig 2A). Fendioxypyracil 495 induced rapid necrosis and led to substantial inhibition in plant tissues that were incubated in 496 light, as observed in Lemna paucicostata, algae and cress seedlings. In addition, the 497 germination and growth of light incubated Arabidopsis thaliana seedlings was strongly 498 inhibited by fendioxypyracil. In contrast, heterotrophically, dark grown Galium cell 499 suspensions were only affected at high concentrations and cress germination in darkness 500 was only mildly inhibited. Carbon dioxide (CO2) assimilation in Galium plants was strongly 501 inhibited by fendioxypyracil. In contrast, fendioxypyracil only slightly affected the Hill reaction 502 and the chlorophyll fluorescence assay, which uses the quantum yield (Y(II)), as an indicator 503 for how much absorbed light energy is used for photochemical reactions in photosystem II 504 (PSII). The above-described results show that even though the overall photosynthesis is 505 affected by fendioxypyracil, it is not based on the direct inhibition of the PSII but it is light 506 dependent. No or only mild effects were observed in the respiration assay as measured 507 through oxygen consumption in heterotrophic Galium cell suspensions and on mitochondrial 508 membrane potentials in Lemna roots. Fendioxypyracil treatment led to rapid necrosis, 509 chlorosis and inhibition of root growth in Lemna; necrosis and inhibition of root growth in the 510 cress germination assay and in Galium plants used for the analysis of CO2 accumulation. 511 To identify the mode of action, we analyzed the P-Profile result by application of a semi-512 supervised variational autoencoder model. The effects of the test compound fendioxypyracil 513 were investigated first by exploration of the learned latent space and second by calculated 514 probabilities for nine target classes (eight known modes of action and ‘Unknown Mode of 515 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 18 Internal Action’) in the multilabel classification prediction. The latent space which has been learned 516 over results derived from a diversity of herbicides including commercially-relevant reference 517 herbicides listed and classified by the herbicide resistance action committee (based on 518 herbicides listed on the HRAC poster 2024 (33), is shown in Figure 2B (latent space). The 519 eight dimensions of the learned latent space have been reduced to two dimensions by 520 UMAP (Uniform Manifold Approximation and Projection) for visualization purpose. 521 Fendioxypyracil (treated as test compound in the model prediction) aligns within a cluster of 522 established PPO inhibitors, saflufenacil, trifludimoxazin, epyrifenacil and tiafenacil (Figure 523 2B, latent space) (4) . The calculated probabilities for eight different known MoA classes and 524 ‘Unknown Mode of Action’ modeled are shown in Fig. 2C (probabilities) and in Table 3 and 525 indicate a probability of over 99% for the MoA PPO inhibition and a very low probability of all 526 other target classes. The very low uncertainty of the prediction as modeled by Monte Carlo 527 dropout and displayed by the spread of the probabilities in Fig. 2C (probabilities) indicates a 528 high reliability of the prediction results. Both the location of fendioxypyracil within the latent 529 space (Figure 2B, latent space) as well as the calculated probabilities of the classification 530 model (Fig. 2C, Table 3, probabilities) indicated PPO inhibition as MoA. 531 For the known PPO inhibitor saflufenacil a P-Profile was already reported by Grossmann et 532 al., 2010 (4) albeit in a slightly refined setup as exploited here. Nevertheless, the inhibitory 533 effects and symptoms in the P-Profile of saflufenacil (i.e. light dependent inhibitory effects on 534 photosynthesis without affecting the PSII and induction of necrotic symptoms, 535 https://doi.org/10.1614/WS-D-09-00004.1) are resembling the profile of fendioxypyracil. 536 Furthermore, we generated profiles with saflufenacil, trifludimoxazin, epyrifenacil and 537 tiafenacil identified in the PPO cluster (Fig. 2B) in the current P-Profile setup and to compare 538 the profiles to that induced by fendioxypyracil. The inhibition profile and the observed 539 symptomology induced by fendioxypyracil were highly similar to those of saflufenacil, 540 trifludimoxazin, epyrifenacil and tiafenacil (Fig 2A, D-G) corroborating the outcome of the 541 classification model. Collectively, these analyses indicated that the MoA of fendioxypyracil is 542 based on the inhibition of PPOs in planta. 543 544 4.2 Fendioxypyracil inhibits both the Amaranth tuberculatus PPO1 and PPO2 wild 545 type enzymes in vitro 546 547 Enzyme inhibition assays confirmed that both PPO1 and PPO2 from A. tuberculatus are 548 strongly inhibited by fendioxypyracil and the benchmark compound saflufenacil, as well-549 characterized PPO inhibitor (34) (Table 4). For PPO1, fendioxypyracil displayed an IC ₅₀ of 550 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 19 Internal 195 nM, whereas saflufenacil was less potent, with an IC ₅₀ of 412 nM. This indicates that 551 fendioxypyracil requires roughly half the concentration of saflufenacil to achieve comparable 552 inhibition of PPO1 activity. A more pronounc ed difference was observed with PPO2, where 553 fendioxypyracil exhibited an IC ₅₀ of only 2.8 nM compared with 11 nM for saflufenacil. Thus, 554 fendioxypyracil inhibited PPO2 with approx imately four-fold greater potency than the 555 benchmark herbicide. At a saturating concentra tion of 10 µM, both compounds fully inhibited 556 PPO1 and PPO2 activity, resulting in 100% loss of enzymatic activity. Taken together, these 557

demonstrate that fendioxypyracil is a highly effective inhibitor of both PPO isoforms in 558 vitro. While saflufenacil confirmed its expected inhibitory activity, fendioxypyracil consistently 559 showed stronger potency, particularly against PPO2, highlighting its potential as a powerful 560 PPO-targeting herbicide. 561 562 4.3 Weed performance of Fendioxypyracil in Post-emergence application in the 563 greenhouse and confirmation in field trials 564 565 The post-emergence greenhouse trials demonstrated that fendioxypyracil is highly effective 566 against a broad spectrum of weed species, including both grasses and broadleaf weeds. At 567 a rate of 16 g active ingredient per hectare, fendioxypyracil controlled more than 80 weed 568 species, as shown in Table 5 (fig 4 and 5). This broad activity was confirmed in multiple field 569 trials, highlighting its robust performance under practical conditions (fig 7). 570 A key finding is fendioxypyracil’s exceptional control of grass weeds—such as wild oat, 571 barnyard grass, crabgrass, and goosegrass—by foliar application in greenhouse pot tests 572 (fig 5 and 6). This level of grass control is unique among PPO inhibitors, which typically 573 show limited efficacy against grasses. In comparative trials in the greenhouse, 574 fendioxypyracil was tested alongside other PPO-inhibiting herbicides (saflufenacil, 575 trifludimoxazin, flumioxazin, tiafenacil), all applied at identical rates and with the same 576 adjuvant. The results showed that all PPO inhibitors provided strong control of broadleaf 577 weeds, with minimal differences in efficacy (Figure 4). However, fendioxypyracil stood out for 578 its consistently high efficacy, even at the lowest tested dose of 1 g ai/ha on the greenhouse, 579 and for its flat dose-response curve, indicating reliable performance across a range of 580 application rates. Fendioxypyracil achieved high average control of broadleaf weeds, 581 matching or exceeding the performance of other PPO inhibitors. Specific weeds such as 582 Amaranthus palmeri (AMAPA), Bidens pilosa (BIDPI), Capsella bursa-pastoris (CAPBP), 583 and Kochia scoparia (KCHSC) were effectively controlled (fig 4). 584 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 20 Internal Fendioxypyracil provided superior control of both cold-season grasses (e.g., Avena fatua, 585 AVEFA) and warm-season grasses (e.g., Digitaria sanguinalis, DIGSA; Eleusine indica, 586 ELEIN) compared to other PPO inhibitors. Notably, only tiafenacil approached similar levels 587 of grass control, but fendioxypyracil maintained a steadier response rate and higher overall 588 efficacy (Figure 5). 589 Fendioxypyracil has demonstrated outstanding efficacy in global field trials. Field data 590 showed (fig 7) that fendioxypyracil achieves rapid and thorough weed control at low use 591 rates (25 g ai/ha) in pre-plant burndown applications, outperforming other PPO inhibitors, 592 especially in grass weed management (ECHCG and Setaria species, SETSS). In the US, 593 fendioxypyracil delivered near-complete control of AMAPA a major driver of herbicide 594 resistance issues. These results position fendioxypyracil as a valuable tool for sustainable 595 weed management in major cropping systems, offering growers a new solution for pre-plant 596 burndown and resistance management strategies. 597 In summary, fendioxypyracil offers outstanding post-emergence weed control, particularly for 598 grass species a significant advancement for PPO-inhibiting herbicides. Its broad-spectrum 599 activity, reliable efficacy at low dose rates, and unique strength against grasses makes it a 600 valuable tool for sustainable weed management in major crops. 601 602 4. Conclusion 603 Fendioxypyracil is a novel PPO-inhibiting foliar herbicide with strong PPO target inhibition, 604 offering broad spectrum weed control (grass and broadleaf weeds) at low use rates. These 605 key attributes will make fendioxypyracil a useful (effective?) preplant burndown herbicide for 606 broad acre crops such as soybeans and corn. Future PPO inhibitor tolerant crops will enable 607 over-the-top applications of fendioxypyracil, thereby broadening its use in future weed 608 management programs. Fendioxypyracil is being developed in many key agricultural 609 countries such as USA, Brazil and Argentina. It is expected to be commercially available in 610 the first countries around the end-2020s, contributing to global food production in the 611 midterm future. Resistance testing is in progress and aims to assess fendioxypyracil activity 612 against PPO-resistant weed populations target site mutant PPO enzymes, and a 613 comprehensive evaluation of resistance mechanisms and management implications will be 614 the objective of a subsequent study. 615 616 5. Acknowledgements 617 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 21 Internal We would like to thank Susanne Knauer, Misha Manuchehri Byrd, Simone Huber, Sarina 618 Rühm und Stefanie Zimmermann for the experimental support. This research did not receive 619 any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. 620 621 6. Conflict of Interest 622 Authors affiliated with BASF have contributed to the planning and implementation of 623 research activities. 624 625 626 627 628 629 630 631 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 22 Internal 7. Tables 632 Table 1: Investigated monocotic weeds and dicot weeds of the Post-Emergence Trial 633 EPPO Code Scientific name English name Authority ABUTH Abutilon theophrasti velvet leaf Medicus AMAPA Amaranthus palmeri palmer amaranth Watson AMARE Amaranthus retroflexus redroot pigweed Linnaeus AMATA Amaranthus x tamariscinus tall amaranth Nuttall AMBEL Ambrosia artemisiifolia common ragweed Linnaeus BIDPI Bidens pilosa hairy beggarticks Linnaeus CAPBP Capsella bursa-pastoris shepherd's purse (Linnaeus) Medicus CHEAL Chenopodium album common lambsquarters Linnaeus COMBE Commelina benghalensis Bengal day flower Linnaeus EPHHL Euphorbia heterophylla wild poinsettia Linnaeus ERICA Erigeron canadensis Canadian horseweed Linnaeus GALAP Galium aparine cleavers Linnaeus IPOHE Ipomoea hederacea morning glory Jacquin KCHSC Kochia scoparia kochia (Linnaeus) Schrader MATCH Matricaria chamomilla wild chamomile Linnaeus PAPRH Papaver rhoeas common poppy Linnaeus RAPRA Raphanus raphanistrum wild radish Linnaeus SEBEX Sesbania herbacea coffeebean (Miller) McVaugh SIDRH Sida rhombifolia common sida Linnaeus SOLNI Solanum nigrum black nightshade Linnaeus XANST Xanthium strumarium common cocklebur Linnaeus ALOMY Alopecurus myosuroides blackgrass Hudson AVEFA Avena fatua wild oat Linnaeus BRARU Brachiaria decumbens Surinam grass Stapf (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 23 Internal BROST Bromus sterilis poverty brome Linnaeus CYPIR Cyperus iria rice flatsedge Linnaeus DIGSA Digitaria sanguinalis crabgrass (Linnaeus) Scopoli ECHCG Echinochloa crus-galli barnyard grass (Linnaeus) Palisot de Beauvois ECHCO Echinochloa colonum small barnyard grass (Linnaeus) Link ELEIN Eleusine indica goosegrass (Linnaeus) Gärtner ERBVI Eriochloa villosa woolly cupgrass (Thunberg) Kunth LEFFA Leptochloa fusca subsp. fascicularis bearded sprangletop (Lamarck) Snow LOLMU Lolium multiflorum Italian ryegrass Lamarck LOLPE Lolium perenne English ryegrass Linnaeus PANDI Panicum dichotomiflorum fall panicum Michaux SETFA Setaria faberi giant foxtail Herrmann SETIT Setaria italica foxtail millet (Linnaeus) Palisot de Beauvois SETVE Setaria verticillate bristly foxtail (Linnaeus) Palisot de Beauvois SETVI Setaria viridis green foxtail (Linnaeus) Palisot de Beauvois SORHA Sorghum halepense Johnson grass (Linnaeus) Persoon * from EPPO Global Database: https://gd.eppo.int/ 634 635 636 637 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 24 Internal 638 Table 2. Application conditions for active ingredients in the Post-Emergence Trial. All actives 639 were applied with 1% MSO (Lecitech) as adjuvant and a water volume of 200 L/ha 640 Active Ingredient Formulation* Rate (g ai ha-1) Water Control Saflufenacil 342 g L-1 SC 8 4 2 1 Trifludimoxazin 500 g L-1 SC 8 4 2 1 Flumioxazin 51% WG 8 4 2 1 Tiafenacil 50 g L-1 ME 8 4 2 1 Fendioxypyracil 342 g L-1 SC 8 4 2 1 *SC: Suspension concentrate, WG: Water dispersible granules, ME: Microemulsion, SL: 641 Soluble liquid concentrate, g ai ha-1: gram active ingredient per hectare 642 643 644 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 25 Internal Table 3. Calculated probabilities computed by a multilabel classification network including 645 nine target classes reveal PPO as the most likely MoA of fendioxypyracil and a very low 646 probability for other modes-of-action target classes. 647 648 Target class Probability ACCase 0.00000 ALS 0.00001 Auxin Mimics 0.00000 HPPD 0.00000 Microtubule Assembly 0.00000 PPO 0.99995 Photosynthesis 0.00005 Unknown Mode of Action 0.00000 VLCFA Synthesis (Elongase) 0.00000 649 650 651 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 26 Internal Table 4. In vitro inhibition of Amaranthus tuberculatus PPO1 and PPO2 wild-type enzymes 652 by fendioxypyracil and the benchmark herbicide saflufenacil. 653 IC₅₀ values (nM) represent the herbicide concentration required to reduce enzyme activity by 654 50%, as estimated from nonlinear regressi on of dose–response curves. Saflufenacil was 655 included as a reference compound. % inhibition values were determined at a saturating 656 concentration of 10 µM, at which both enzymes were fully inhibited. Each value is an 657 average of three replications (P < 0.0001). 658 659 660 661 662 PPO isoform Enzyme backbone Fendioxypyracil IC50[nM] P<0.0001 Saflufenacil IC50[nM] P<0.0001 Fendioxypyracil % Inhibition at saturation Saflufenacil % Inhibition at saturation PPO1 AMATU 195 412 100 100 PPO2 AMATU 2.8 11 100 100 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 27 Internal Table 5 Examples of weeds controlled by fendioxypyracil in Greenhouse at 16 g/ha 663 Weed Type Broadleaf weeds Abutilon theo phra s ti, Amar anthu s pal m e r i , Amaran thu s re t r ofl ex us, Amaran thu s x tama r i sci nu s , A m bro sia artem i s ii fo lia, Bi den s pilo sa, Cap sell a bursa -pa st ori s , Cen taur ea c yanu s, Che nop odium a lbum, C ir sium arven se, Comm elina b enghal en s i s , Co nv olvu lus arven si s, Euphorbia hete rophyll a, Eri oc hloa v illo sa, E r ig e ron ca naden si s, G a lium a pa rine, G e ra nium dis se ctum, Gera nium pus i l lum, Ipo moea h ed e r a cea , Ipomo ea lac unose , Koch ia scopa ria , La mium ampl exic aule, Lami um purpur eum, Matr i ca ria chamomi lla, M a tric aria ino dora , O ry z a ru fipog on , Pa nicum dicho t omi fl or u m, Panic um mil iace um, P a pa ver rho ea s, Phy s a li s ixoc arpa , Polyg onum c onvolv ulus, Por t u laca ol erac ea, P ortul ac a ol e r a cea s ub sp . s a t iv a, Ra pha nu s rapha nis trum, S al sola k al i s u b s p . ruth eni ca, S e sbania herbac e a, Si da rh ombifoli a, Si napi s al ba , Sina pis arven si s , Sola n um nigrum, S onchus ole ra ceu s, St ell ari a medi a, Ta r a xac um of fici nale , T hla spi arven se, Ver onic a pe rsica , Viol a arven si s, Xanthium s trumarium Grasses Agro s ti s s tol o nif era , Alopec u ru s m yosu r o ides, A p e r a s p ica -v enti, Avena fatu a, Br ac hiaria de cumbe n s , B rac hiari a plantagi n ea, Br omus in ermi s, B r om us st e r i li s, C y p e r us es c u le nt us , Cy pe r us i r i a , D i g it a r i a s an g u i n al is , Echi nochlo a cru s-galli , Ech inochl oa c olon um, El eusin e indi ca, E r i ochl oa vill os a, Is c h aemum r ug o s um , Lep toc hloa c hinensi s , Le ptochl oa fu s c a s ub sp . fa sc icula r is , L eptochl o a muc r ona te , Lol ium multiflo rum, Lolium perenn e, O ryza ru fipogon, Panic um dic h otomifl orum, P a nicum miliac eum, Pa spalum n o t a t u m , Phal a r i s c anari en si s, Poa annu a, Ro t tbo el lia coc hinch inen si s , Se taria fa b er i , Se tar ia it alic a, Se ta r i a ver tic illa te, Se tar ia viridis, S o r g hum hale p en s e 664 665 666 667 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 28 Internal 8. Schemes and Figures 668 669 670 1 34 2 5 Novartis 1999 Syngenta 2001 Syngenta 2004 BASF 2017 Fendioxypyracil 671 Scheme 1: Discovery of PPO herbicide structures with a central pyridine core 672 673 674 675 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 29 Internal 5 a b,c d,e f,g 67 8 9 676 Scheme 2: Fendioxypyracil synthesis: (a) i) NaN3, ii) 2-(Benzyloxy)phenol; (b) Zn, NH4Cl; 677 (c) ethyl chloroformate; (d) ethyl (E)-3-amino-4,4,4-trifluoro-but-2-enoate; (e) MeI; (f) AlCl3; 678 (g) ethyl bromoacetate. 679 680 681 682 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 30 683 Figure 1: Histograms of the dihedral angle distributions for the phenyl-core (left) and 684 pyridine-core (right) variants. The 3D structures, which correspond to the conformations 685 observed in the protein binding pocket, are shown in stick representation. Carbon atoms are 686 colored white, nitrogen blue, oxygen red, chlorine dark green, and fluorine light green. The 687 angles shown in the histograms are indicated in the structures by black arrows. 0° (magenta 688 line in the histograms) means the C–C–O–C (phenyl) or N–C–O–C (pyridine) atoms lie in the 689 same plane (shown as magenta plane in the 3D structures). 690 691 692 693 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 31 694 Figure 2: (A, D-G) (A) Physiological profiles of fendioxypyracil, saflufenacil, trifludimoxazin, 695 epyrifenacil and tiafenacil. Effect of respective compounds on heterotrophic Gallium mollugo 696 cell suspensions, green algae Scenedesmus obliquus, Lemna paucicostata plants, 697 Arabidopsis thaliana seedling morphology, germination of cress (Lepidium sativum L.) under 698 dark/light conditions, the Hill reaction in isolated Triticum aestivum chloroplasts, CO2 699 assimilation in G. mollugo plants, oxygen consumption (respiration) in heterotrophic G. 700 mollugo cell suspensions, uncoupler activity and accumulation of reactive oxygen species 701 (ROS) in L. paucicostata root tissue, chlorophyll fluorescence, and ATP content are shown. 702 Uncoupler activity and ROS accumulation are shown as effect compared with control, while 703 values of all other assays are expressed as percentage of inhibition. Letters indicate 704 physiological symptoms observed: rapid necrosis (NR), necrosis (N), root growth inhibition 705 (I), chlorosis (C) and inhibition of germination (K) (B) Latent Space learned by a variational 706 autoencoder model using P-Profile results generated for a diversity of herbicides. 707 Dimensional reduction of the latent space has been performed by UMAP. Pesticides with 708 unknown target class are shown in light grey along pesticides with known target classes, 709 highlighted in red for known PPO (protoporphyrinogen oxidase) inhibitors, namely 710 saflufenacil, trifludimoxazin, epyrifenacil and tiafenacil, and in dark grey for eight additional 711

target classes detailed in C. The test compound fendioxypyracil is displayed as 712 light grey dot with a black border. Fendioxypyracil aligns with known PPO inhibitors in the 713 latent space (C) Calculated probabilities (y axis) computed by a multilabel classification 714 network including nine target classes (x axis). Prediction uncertainty has been assessed by 715 Monte Carlo dropout and is shown as spread (y axis). 716 717 718 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 32 719 Figure 3. Dose–response curves showing percent inhibition of (left) PPO1 and (right) PPO2 720 by fendioxypyracil (red circles) and Saflufenacil (green triangles). Enzymatic activity was 721 measured across a range of inhibitor concentrations (0.001–100,000 nM), and percent 722 inhibition was calculated relative to the activity of enzyme with no herbicide (positive control). 723 Data points represent mean values from three replications, and curves were fitted using a 724 four-parameter logistic model to estimate IC₅₀ values (Table 4). 725 726 727 728 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 33 729 730 Figure 4: Broadleaf weed (BLW) control in greenhouse. Represented is the BLW average 731 control as well as activity against specific BLW, such as AMAPA, BIDPI, CAPBP, KCHSC. 732 The assessment was done 20 days after treatment 733 734 735 736 0 10 20 30 40 50 60 70 80 90 10 0 12 48 12 48 12 48 12 48 12 48 [ g a i/ h a] [ g a i/ h a] [ g ai/ h a] [ g ai/ h a] [ g ai/ h a] F e ndi ox y py r ac il Ti af e na c il T r if l ud imo x az in S af l uf e na ci l F lu mi ox az in BL W me an AMA PA BI D P I CAP B P KC HS C (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 34 737 738 Figure 5: Grass control after greenhouse application. Represented is the mean grass control 739 as well as activity against AVEFA as cold season grass, DIGSA, ELEIN and ECHCG as 740 warm season grasses. The assessment was done 20 days after treatment. 741 742 743 744 0 10 20 30 40 50 60 70 80 90 10 0 12 48 12 48 12 48 12 48 12 48 [ g a i/ h a] [ g a i/ h a] [ g ai/ h a] [ g ai/ h a] [ g ai/ h a] F e ndi ox y py r ac il Ti af e na c il T r if l ud imo x az in S af l uf e na ci l F lu mi ox az in gras s mean AVE FA DI GS A EL EIN ECH CG (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 35 745 746 Figure 6: Grass activity in glasshouse pot trial. Post-emergence application on wild oat, 747 crabgrass and goosegrass. Comparison of fendioxypyracil, saflufenacil and flumioxazin. 748 Spray volume 200 L/ha with 0.5 % MSO, 20 Days after treatment 749 750 751 752 753 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 36 754 755 Figure 7: Field Trials in Seymour, IL, USA. Pre-Plant Burndown application, using 200 l/ha 756 with 0,5 % MSO and 1 % AMS. 9 days after application. Control of AMASS, ECHCG and 757 SETSS 758 759 760 761 762 763 764 765 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint 37 Internal 766

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Gro ssmann K , Ch ri s tia nsen N , Loo s er R, T re sch S , Hutz l er J , Po llmann S , Ehrhardt T. 832 Phy s io no mics a nd m eta bolomic s —two k ey a pproache s i n h erbici dal mod e of ac t i o n discove r y . Pe s t 833 Mana gemen t S cienc e . 20 12;68(4 ):494 -5 0 4. 834 33. http s: //www .hracg lobal.c om /. 2025 [ 835 34. Porri A, Be tz M, Se ebruck K, Knapp M, Jo hnen P, W i tsche l M , et al . Inhibi tion pro f i le of 836 trifl udimox az i n towar ds PP O2 ta rget si te mutation s . P es t Man age men t Sc ience . 2 023;7 9(2) :507-19 . 837 838 839 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted January 5, 2026. ; https://doi.org/10.64898/2026.01.05.697680doi: bioRxiv preprint