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Fluazifop-p-butyl (FPB) is an herbicide that inhibits the enzyme acetyl-CoA carboxylase (ACCase), which is active in lipid biosynthesis in plants. This study evaluates the effects of FPB on the behaviour, brain acetylcholinesterase, biochemical parameters, and hematological indices in orally exposed rats. Thirty-two (32) male albino rats (Rattus norvegicus) (80 - 188 g) were randomly grouped into A to D. Group-D served as control, while animals in groups A, B, and C received FPB at 75 mg/kg, 37.5 mg/kg, and 18.75 mg/kg, respectively, for 14 days. FPB caused significant changes in behaviour, acetylcholinesterase, some biochemical parameters, and some hematological indices at p < 0.05. When compared to the control group, the treatment group exhibited a generally torpid state, a lower reactivity to touch, and decreased food consumption. These responses abated during the 7 days of withdrawal. It was found that the white blood cell (WBC) total count decreased in treatment groups compared to control. This decrease was duration- and dose -dependent even after the 7 days of withdrawal. Neutrophil count followed the pattern of WBC total count, while lymphocyte count increased significantly. Urea, creatinine, alanine transaminase, aspartate transaminase, alkaline phosphatase, acid phosphatase, and acetylcholinesterase significantly increased (p < 0.05), while total protein and glucose significantly decreased following the administration of FPB. Hepatosomatic indices were not affected in the FPB-treated groups. Overall, the results suggest that FPB modulates the behaviour, acetylcholinesterase, and haematological and biochemical parameters in rats. [ABSTRACT FROM AUTHOR]

Fluazifop-P-butyl is a commercial herbicide commonly used in agricultural practices for controlling grass weeds. The present work aimed to detect and compare the deleterious changes that may occur in the kidney of the African catfish, C. gariepinus under the different concentrations of fluazifop-P-butyl, as well as studying the histopathological changes in the kidney of exposed fishes to different levels of the selected pollutant. Fish were exposed to different concentrations (1.72 & 0.57 mg/L) of fluazifop-P-butyl for different periods (14 and 28 days). At the end of the exposure time, the levels of uric acid, creatinine and urea were measured in the blood serum to determine kidney functions. In addition, a histopathological examination of the kidney was performed to assess the impact of fluazifop-P-butyl on its tissue structure. The results showed that exposure of catfish Clarias gariepinus to fluazifop-P-butyl led to a significant increase in the levels of uric acid, creatinine, and urea in the serum, indicating impairment in kidney functions. The histological examination revealed pathological changes in the kidney structure, including degeneration of renal cells, atrophy of renal tubules and interstitial fibrosis. The findings of this study highlighted the importance of considering the potentially toxic effects of fluazifop-P-butyl on aquatic organisms upon using this herbicide in agricultural practices. [ABSTRACT FROM AUTHOR]

Invasive plant species create barriers to native species' reestablishment after land degradation. Postemergent herbicides are preferred (over preemergent) for use in restoration as they are not expected to affect native seeds. However, recent studies found that postemergent herbicides can persist in soils and reduce native species' seed germination and seedling emergence. Activated carbon seed enhancement technologies (SETs) can protect seeds from preemergent herbicides but are untested with postemergent herbicides. We explored the effects of two postemergent herbicides, Roundup and Fusilade, on seedling emergence and health of five species native to Banksia Woodlands of Western Australia. We investigated if activated carbon SETs protect seeds and seedlings from any negative effects caused by herbicide application. A randomized block design was used, and herbicide applied to the soil after seeds (nonenhanced and enhanced with activated carbon SETs) were sown under field conditions. Roundup considerably reduced seedling emergence of Acacia pulchella, Banksia menziesii, and Eucalyptus todtiana, whereas Fusilade did not negatively affect emergence. Both herbicides considerably reduced seedling health for A. pulchella, B. menziesii, and E. todtiana. Activated carbon increased A. manglesii emergence in all treatments. Activated carbon also notably increased the percentage of healthy A. pulchella, B. menziesii, and E. todtiana seedlings in herbicide treatments, indicating that activated carbon can provide protection from postemergent herbicides applied to the soil before seedling emergence. Roundup and Fusilade should not be used in restoration when soil seed banks are the source of native seeds, and a time lag is required when direct seeding after herbicide application. [ABSTRACT FROM AUTHOR]

The relatively high temperature at Kessem sugarcane plantation in Ethiopia was hypothesized to justify the implementation of chemical ripeners as a strategic intervention to combat poor cane quality. Accordingly, a field experiment was carried out to assess the responsiveness of four sugarcane varieties (B52-298, NCo334, C86-12, and SP70-1284) to five ripener treatments: 2-chloroethylphosphonic acid (Ethephon™, 480 g ai L−1) at 720 g ai ha−1, fluazifop-p-butyl (Fusilade Forte™, 150 g ai L−1) at 25.6 g ai ha−1, trinexapac-ethyl (Moddus™, 250 g ai L−1) at 250 g ai ha−1, 2-chloroethylphosphonic acid + fluazifop-p-butyl combination at the mentioned application rates, trinexapac-ethyl + fluazifop-p-butyl combination at the mentioned application rates, and an untreated control. The experiment was conducted in a factorial arrangement in a randomized complete block design (RCBD) with three replications. The results showed that stalk height, stalk weight, sucrose content (%), and sucrose yield (t ha−1) were affected by the main effect of ripener treatment, but there was no significant cultivar x ripener treatment interaction for the parameters collected. Overall, the sequential application treatment of trinexapac-ethyl followed by fluazifop-p-butyl 28 days later performed the best and improved sucrose content and sucrose yield by 2.64% unit and 2.15 t ha−1, respectively. In economic terms, the trinexapac-ethyl + fluazifop-p-butyl sequential application treatment resulted in a marginal rate of return of 2393%. Therefore, the sequential trinexapac-ethyl + fluazifop-p-butyl ripener program was identified as a promising ripening strategy to be evaluated on a commercial scale at the sugarcane plantations in Ethiopia. [ABSTRACT FROM AUTHOR]

A two-year field experiment was conducted at experimental farm, Faculty of Agriculture, Kafrelsheikh University, Egypt during both 2015/2016 and 2016/2017 successive winter growing seasons to the effect of some pre and postemergence herbicides on physiological and histological characters, productivity and quality of carrots (cv. "Tokita"). Each experiment included nine weed control treatments which consists of four herbicides (three herbicides used as pre-emergence i. e. prometryn 312.5 or 625g; linuron 112.5 or 225g and pendimethalin 425 or 850 g a. i./fed. while the other herbicide i. e. fluazifop-p-butyl 62.5 g was used as post-emergence, and hand hoeing twice (at 30 and 45 DAS) and weedy chick. Significant differences on chlorophyll content (chi. a, b and total) were induced during the both seasons. Prometryn gave the highest value of chlorophyll a. Pendimethalin gave the highest value of RWC and least of LWD. The highest values of carrot root half diameters and cortex tissue thickness were detected by pendimethalin treatment. All tested herbicides gave the highest values of quality characters in carrot roots, followed by hand weeding of the annual weeds. [ABSTRACT FROM AUTHOR]

When making decisions about how to restore habitat for at-risk species, land managers must balance multiple competing objectives in the face of uncertainty about the impacts of management actions on at-risk populations. The Oregon silverspot (Speyeria = Argynnis zerene hippolyta) is a federally threatened butterfly, and uncertainty exists about the effects of proposed management. We used structured decision making (SDM) to guide restoration for Oregon silverspots. Managers identified persistence as their primary objective and further identified effects of herbicides as a key uncertainty. We developed a model of population dynamics incorporating management actions and parameterized the model based on experiments with a surrogate subspecies, the Zerene silverspot (S. z. zerene). Herbicide application may directly harm Oregon silverspots by increasing larval mortality, while indirectly benefiting silverspots by reducing the competition faced by their host plant. In this system, potential herbicide treatments include grass-specific fluazifop-P-butyl or forb-specific clopyralid applied with Agri-Dex® or Nu-Film®-IR adjuvants. We found that Oregon silverspot population growth rate is greatest with clopyralid and fluazifop-P-butyl when combined with Nu-Film®-IR than other alternatives (including no treatment) considering only direct effects or in combination with indirect effects. An adaptive management program would benefit Oregon silverspots by promoting exploration of management alternatives while allowing managers to act quickly to arrest steep declines. Uncertainty remains regarding how well our results will generalize in field conditions. Implications for insect conservation: SDM, in combination with experiments to parameterize models, provides a powerful tool for evaluating risks from management actions relative to conservation benefits. [ABSTRACT FROM AUTHOR]

Herbicides are used as management tools to improve habitat for native plants and animals, but their application may also have harmful effects on the native community. The federally threatened Oregon silverspot butterfly (Speyeria = Argynnis zerene hippolyta) resides in remnant native grasslands along the Pacific Northwest coast. However, like many grasslands, many of these areas have high incidences of invasive plants, such as false dandelion (Hypochaeris radicata) and velvet grass (Holcus lanatus). These and other invasive plants severely limit the abundance of the Oregon silverspot's larval host plant, the early blue violet (Viola adunca). Selective herbicides, such as clopyralid and fluazifop-P-butyl, can reduce invasive plant abundance. However, non-target effects of these herbicides, and of adjuvants applied with these herbicides, on Oregon silverspots are unknown. In our study, we applied herbicides and adjuvants to host plants and Zerene silverspot (S. z. zerene) larvae, a subspecies closely related to Oregon silverspots. Responses in silverspot larvae measured in two experiments included survival, sex ratio, development time, mass, morphology, fecundity, and behavior. Our results suggest that negative effects of herbicides, clopyralid and fluazifop-P-butyl, and adjuvants, Agri-Dex® and Nu-Film®-IR, are limited. However, we detected weak effects from clopyralid and fluazifop-P-butyl with and without Agri-Dex® on larval and pupal development time and pupal mass. Implications for insect conservation: Our study contributes to the growing literature on non-target effects of herbicides on butterflies, which suggests that butterfly responses are species- and chemical-specific. For Speyeria species, our results indicate that the risks posed by the herbicides we examined are low. In management settings where herbicides are used to combat invasive species posing a conservation threat to native communities, monitoring the direct and indirect effects of herbicides on Oregon silverspots or other Speyeria butterflies will shed additional light on the risk–benefit tradeoffs. [ABSTRACT FROM AUTHOR]

The usefulness of 3 herbicides and flame weeding in lemon balm sown directly into the field was assessed in a two-year experiment. Glufosinate-ammonium (600 g·ha-1) and flame weeding (90 kg propane·ha-1) were applied 12-13 days after lemon balm sowing, i.e. shortly after weed emergence and 4 days before crop emergence. Bentazon (960 g·ha-1) and fluazifop-P-butyl (150 g·ha-1) were sprayed approximately 3 weeks after sowing, during the emergence of lemon balm, and when the weeds were in the cotyledon -- 2-4 true leaves stage. All of the studied weed control methods significantly reduced the number and fresh weight of weeds growing 4 weeks after lemon balm sowing. The most effective method was spraying with glufosinate-ammonium, which controlled 69-76% of weeds. The efficiency of flame weeding was slightly lower. Bentazon caused slight, temporary chlorosis of some lemon balm cotyledons. Content of essential oil (1.9-2.1%), its composition and content of rosmarinic acid (2.08-2.44%) in lemon balm leaves, as well as content of total nitrogen (2.18-2.55%), phosphorus (0.30-0.32%), potassium (2.94-3.22%), calcium (1.02-1.60%), and magnesium (0.30-0.32%) in lemon balm raw material were independent of the weeding method. Content of essential oil, phosphorus, potassium and calcium were significantly higher in the dryer year. Studied weed control methods proved useful in the cultivation of lemon balm from direct sowing into the field. Methods with total action (flaming and glufosinate-ammonium) were more effective than those with selective herbicides (bentazon and fluazifop-P-butyl). [ABSTRACT FROM AUTHOR]

The usefulness of 3 herbicides and flame weeding in lemon balm sown directly into the field was assessed in a two-year experiment. Glufosinate-ammonium (600 g∙ha–1) and flame weeding (90 kg propane∙ha–1) were applied 12–13 days after lemon balm sowing, i.e. shortly after weed emergence and 4 days before crop emergence. Bentazon (960 g∙ha–1) and fluazifop-P-butyl (150 g∙ha–1) were sprayed approximately 3 weeks after sowing, during the emergence of lemon balm, and when the weeds were in the cotyledon – 2–4 true leaves stage. All of the studied weed control methods significantly reduced the number and fresh weight of weeds growing 4 weeks after lemon balm sowing. The most effective method was spraying with glufosinate-ammonium, which controlled 69–76% of weeds. The efficiency of flame weeding was slightly lower. Bentazon caused slight, temporary chlorosis of some lemon balm cotyledons. Content of essential oil (1.9–2.1%), its composition and content of rosmarinic acid (2.08–2.44%) in lemon balm leaves, as well as content of total nitrogen (2.18–2.55%), phosphorus (0.30–0.32%), potassium (2.94–3.22%), calcium (1.02–1.60%), and magnesium (0.30–0.32%) in lemon balm raw material were independent of the weeding method. Content of essential oil, phosphorus, potassium and calcium were significantly higher in the dryer year. Studied weed control methods proved useful in the cultivation of lemon balm from direct sowing into the field. Methods with total action (flaming and glufosinate-ammonium) were more effective than those with selective herbicides (bentazon and fluazifop-P-butyl).

The widespread use of pesticides contributes to their existence in the environment. The compounds with photocatalytic activity in environmental matrixes play a significant effect on the photodegradation of pesticides. In order to clear the photolysis effects of the main characteristic inorganic metal elements in the of Panax ginseng field soil on fluazifop-p-butyl, a series of tests were carried out. The obtained results indicated that Mn2+ and Sn+ exhibited a significant photosensitization on the ultraviolet photodegradation of fluazifop-p-butyl. Also the high content of VO3– and Mo7O246– in the photolysis system showed a photoquenching on fluazifop-p-butyl, but the low content is a photosensitive effect. However, in the photolysis system, as the concentration of Co2+ and Li+ increases, the photoquenching effect on fluazifop-p-butyl becomes obvious, and no photosensitization at any tested concentration of them. [ABSTRACT FROM AUTHOR]

Weeds represent a major constraint for successful pea cultivation, resulting in loss of green pea yield and quality. Two field experiments were carried out during the winter seasons of 2018/2019 and 2019/2020. The objectives of the current study were to evaluate the efficacy of pendimethalin, butralin, fluazifop butyl, bentazon, and hoeing on weed control, and their impact on pea growth, nodule formation, yield, quality, and storability. The results indicated that hoeing and fluazifop butyl were the most effective treatments for weed control in terms of the lowest values of total weed dry weight. The bentazon and fluazifop butyl herbicides didn’t affect active nodules number, plant height, plant weight, root length, or number of leaves and branches. Additionally, bentazon and hoeing resulted in the highest total yield per plant and protein content. Butralin and pendimetalin achieved the lowest yield, and butralin also resulted in the lowest plant height and weight. Bentazon-treated peas had the highest chemical compositions in terms of chlorophyll, carotenoids, total sugar, and vitamin C contents in pea pods at harvest and during cold storage at 4 °C and 95 RH for 45 days. No detectable residues of the four herbicides under study were detected in green pods, suggesting that pods can be safely consumed at the time of harvesting. It can be concluded that nodules formation in pea was not affected significantly by the application of the tested herbicides, except pendimethalin and butralin. Furthermore, bentazon had a positive impact on nodules formation and pods quality and could be used effectively for controlling the broadleaf weeds, and it was simultaneously a selective and safe herbicide in pea cultivation. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herbicides have been used to control Brachiaria grass in pastures established or in formation given their practicality, however their efficiency is questionable due to the lack of specific graminicides for different forage species. Therefore, the goal of this study was to evaluate the efficiency of glyphosate and fluazifop-p-butyl in the control of Brachiaria decumbens (signalgrass) and the intoxication levels of Panicum maximum cv. Tanzania (Tanzania quinea grass) in pasture establishment. The experiments were designed in randomized blocks, in a 2 × 5 × 4 factorial arrangement of two herbicides (fluazifop-p-butyl and glyphosate), five doses equivalent to the commercial dosage of each herbicide (0.25; 0.50; 1.00; 1.50; 200), and four evaluation times after herbicide application (15, 21, 30 and 45 days). There was interaction between doses and evaluation times. The dose 1.5 L ha-1 fluazifop-p-butyl provides efficient control of signalgrass, however, leads to high intoxication in Tanzania guinea grass. Glyphosate is efficient in the control of signalgrass even at the lowest dose (90 g ha-1), however, it causes high intoxication in Tanzania guinea grass, preventing its use in developing pastures. It can be concluded that fluazifop-p-butyl and glyphosate herbicides are not recommended for the control of B. decumbens, cv. Basilisk in developing pastures of Tanzania guinea grass.

Sunflower is an important industrial crop since it is grown all over the world for oil production, while Johnsongrass (Sorghum halepense (L.) Pers.) is characterized by great competitiveness and can severely impair plant growth and crop productivity. Thus, a two-year field experiment was conducted to evaluate the impact of Johnsongrass control practices on plant growth, seed yield, and oil content of sunflower crop. The results indicated that Johnsongrass competition negatively affected sunflower growth and productivity as the lowest values of height, dry biomass, seed, and oil yields were recorded at the weed-infested treatment, followed by the weed infested for 30 days after sowing. All the other treatments had a positive effect on vegetative and yield parameters. Moreover, fluazifop-p-butyl, quizalofop-p-ethyl, and the combination of fluazifop-p-butyl and imazamox effectively controlled Johnsongrass. Specifically, in 2020, the lowest dry weight of Johnsongrass was observed in the plots where fluazifop-p-butyl + imazamox were applied. Thus, the results of this study clearly showed that the use of the above-mentioned herbicides can improve the seed and oil yield of a sunflower crop by managing Johnsongrass, while the competition of this rapidly growing weed for a short period of 30 days can significantly reduce crop yield.

Field experiments were conducted to evaluate the efficacy of glyphosate (H1) and fluazifop- -P-butyl (H2) herbicides with adjuvants on the common reed without cutting and at two different cutting levels (10 and 30 cm). The adjuvants were urea, nitric acid and sulfonic acid. The relative importance value (RIV), leaf chlorophyll content and plant density were determined to assay the efficacy of herbicides. Glyphosate treatment only (H1a) was more effective than fluazifop-P-butyl (H2a) on reeds without cutting and at the 10 cm cutting level. However, no significant difference was observed between them at the 30 cm cutting level. A positive effect of plant cutting occurred on the efficacy of all herbicides applied alone or in a tank mix with adjuvants. Furthermore, the 10 cm cutting level was more effective in eradication of reeds than the 30 cm cutting level. The adjuvants significantly improved the efficacy of the recommended (Hb) and half recommended (Hc) herbicide rates in comparison to being used alone on uncut reeds. The reduction percentages were 94.5, 86.99, 76.61 and 69.94 for H1b, H1c, H2b and H2c treatments, respectively. However, the adjuvants did not improve the glyphosate effect at different levels of cutting. Conversely the reduction percentage of reeds was improved by the recommended rate of fluazifop-P-butyl with adjuvants (H2b) to 92.77% and 84.62% at 10 and 30 cm cutting levels, respectively.

Fluazifop‐p‐butyl (FPB) is used to control the gramineous weeds in Panax ginseng field, which has the risk of exceeding the maximum residue limit of FPB in Panax ginseng. A modified QuEChERS sample preparation method was developed for the simultaneous determination of FPB and its two major relevant metabolites, fluazifop‐p‐acid (FP) and 2‐hydroxy‐5‐ trifluoromethylpyridin (TFMP) in Panax ginseng by using Carboxylated multi‐walled carbon nanotubes (MWCNTs‐COOH) mixed with ostade‐cylsilane (C18), primary secondary amine (PSA), and graphitized carbon black (GCB) as purification materials. Furthermore, the HPLC‐MS/MS parameters were optimized. The method was further validated by determining the linearity (R2>0.999), fortified recovery (77.6‐97.8%), relative standard deviation (<13.6%) and sensitivity (LOQ, 2.0‐ 8.6 μg kg‐1 for FPB, 3.9‐5.8 μg kg−1 for FP and 3.5‐9.0 μg kg−1 for TFMP in Panax ginseng root, leaf, and seed samples, respectively). The main advantages of the method are high recovery, high sample throughput, facile sample preparation, a smaller volume of organic solvents and low cost per sample. The entire method can withstand practice testing expected to be used for the screening of FPB residue in Panax ginseng samples. [ABSTRACT FROM AUTHOR]

Abstract The usage of pesticides has been steadily increasing over the last decades, and among them herbicides are the most commonly used ones. Despite their main mode of action targeting plant organisms, they can also have adverse effects on non-target animal organisms. In soil ecosystems, earthworms play an important role due to their positive impacts on the soil functioning and they represent good model organisms in soil ecotoxicology. The aim of the present study was to assess the effects of two herbicides on several endpoints at different levels of biological organization in the earthworm Eisenia andrei. Diuron and fluazifop- p -butyl were selected for the investigation and their lethal concentrations were determined: LC 50 48 h: 89.087 μg/cm2 for diuron and 6.167 μg/cm2 for fluazifop- p -butyl. Furthermore, measurements of enzymatic biomarkers (catalase (CAT), acetylcholinesterase (AChE), carboxylesterase (CES) and glutathione S-transferase (GST)), multixenobiotic resistance (MXR) activity and gene expression of antioxidative enzymes (only for fluazifop- p -butyl) were conducted. Enzymatic biomarker responses showed no significant differences compared to the control after the exposure to the investigated herbicides, whereas the MXR activity was significantly inhibited. The gene expression level of superoxide dismutase (sod) and glutathione S-transferase (gst) after fluazifop- p -butyl exposure showed a significant increase. Finally, avoidance behavior in soil was assessed and it was determined that both herbicides caused significant avoidance response. The obtained results show that both investigated herbicides significantly affect earthworms on different levels of biological organization. This emphasizes the importance of comprehensive ecotoxicological assessment of herbicide effects on non-target organisms at all organizational levels. Highlights • Exposure of earthworm Eisenia andrei to herbicides diuron and fluazifop- p -butyl. • Significant effects at both lower and higher level endpoints were observed. • Both herbicides caused a significant inhibition of the MXR activity. • Both herbicides caused a significant avoidance response. • Fluazifop- p -butyl caused an increase in the gene expression level of sod and gst. [ABSTRACT FROM AUTHOR]

Field experiments were conducted to evaluate the efficacy of glyphosate (H1) and fluazifop- -P-butyl (H2) herbicides with adjuvants on the common reed without cutting and at two different cutting levels (10 and 30 cm). The adjuvants were urea, nitric acid and sulfonic acid. The relative importance value (RIV), leaf chlorophyll content and plant density were determined to assay the efficacy of herbicides. Glyphosate treatment only (H1a) was more effective than fluazifop-P-butyl (H2a) on reeds without cutting and at the 10 cm cutting level. However, no significant difference was observed between them at the 30 cm cutting level. A positive effect of plant cutting occurred on the efficacy of all herbicides applied alone or in a tank mix with adjuvants. Furthermore, the 10 cm cutting level was more effective in eradication of reeds than the 30 cm cutting level. The adjuvants significantly improved the efficacy of the recommended (Hb) and half recommended (Hc) herbicide rates in comparison to being used alone on uncut reeds. The reduction percentages were 94.5, 86.99, 76.61 and 69.94 for H1b, H1c, H2b and H2c treatments, respectively. However, the adjuvants did not improve the glyphosate effect at different levels of cutting. Conversely the reduction percentage of reeds was improved by the recommended rate of fluazifop-P-butyl with adjuvants (H2b) to 92.77% and 84.62% at 10 and 30 cm cutting levels, respectively. [ABSTRACT FROM AUTHOR]

In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant Syngenta Crop Protection AG submitted a request to the competent national authority in Portugal to modify the existing maximum residue level (MRL) for the active substance fluazifop-P in tomato. The data submitted in support of the request were found to be sufficient to derive MRL proposal for tomato. An adequate analytical method for enforcement is available to control the residues of fluazifop-P in tomato at the validated limit of quantification (LOQ) of 0.01 mg/kg. Based on the risk assessment results, EFSA concluded that the short-term and long-term intake of residues resulting from the use of fluazifop-P according to the reported agricultural practice is unlikely to present a risk to consumer health. [ABSTRACT FROM AUTHOR]

The herbicide Fusilade Forte ® (FF) is widely applied in agricultural weed management and in the management of the invasive saltmarsh grass, Spartina anglica (ricegrass or cordgrass). FF (active ingredient fluazifop-P acid, FPA) is selective for poaceous grasses. Its primary mode of action is inhibition of the acetyl coenzyme-A carboxylase (ACCase) specific to this taxonomic group, and its secondary mode is by promotion of oxidative stress. FF is applied to S. anglica infestations in the intertidal zone, in proximity to seagrass meadows. Despite the potential for vital seagrass ecosystems to be exposed to FF, there is limited knowledge of any potential impacts. We investigated impacts of FPA on the endemic Australian seagrass, Zostera nigricaulis , measuring ACCase activity and parameters that reflect oxidative stress: photosynthetic performance, lipid peroxidation and photosynthetic pigment content. Seagrass was exposed to FF (0.01–10 mg L −1 FPA and a control) for 7 d, followed by a 7-d recovery in uncontaminated seawater. An enzyme assay demonstrated that FPA ≤10 mg L −1 did not inhibit the activity of ACCase isolated from Z. nigricaulis , demonstrating that this seagrass is resistant to FF's primary mode of action. However, physiological impacts occurred following 7 days exposure to ≥0.1 mg L −1 FPA, including up to a 72% reduction in photosynthetic pigment concentration. After 7-d recovery, photosynthetic pigment content improved in treatment plants; however, treated plants exhibited higher levels of lipid peroxidation. This study demonstrates that while Z. nigricaulis is resistant to FF's primary mode of action, significant physiological impacts occur following 7 days exposure to ≥0.1 mg L −1 FPA. This study provides valuable information on the effects of FF on a non-target species that can better inform approaches to Spartina management in coastal seagrass ecosystems. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Different doses of herbicides can promote a differentiated physiological response in grasses of the same genus. This study has been proposed in order to evaluate physiological responses of B. ruziziensis and B. decumbens submitted to glyphosate and fluazifop-p-butyl. Treatments were distributed in a 2 x 6 factorial design with five repetitions, being two grasses: B. decumbens cv. Basilisk and B. ruziziensis with six doses of herbicides: 0.00; 0.25; 0.50; 1.00; 1.5 and 2.00 times the commercial dose recommended by manufacturers. At 7, 15, 21, and 30 days after herbicide application (DAA) chlorophyll luminous energy uptake efficiency was evaluated. Plants subjected to glyphosate at 7 days after application (DAA) showed minimum fluorescence of 270 and 245 quantum-1 electrons to B. ruziziensis and B. decumbens, respectively, levels increased by 350% when compared to the control, and at 15 DAA the treated plants have completely dried up. At 15 DAA, both forage species submitted to the fluazifop-p-butyl showed a 25% reduction in Fv/Fm ratio compared with the control and there was no significant difference between the lowest and highest doses applied. B. ruziziensis and B. decumbens are more sensitive to glyphosate than fluazifop-p-butyl. Regarding fluazifop-p-butyl, B. ruziziensis was more sensitive than B. decumbens and at 45 days after cutting B. decumbens plants submitted to doses up to 100 g ha-1 were able to regenerate their photosynthetic apparatus.

Acanthospermum hispidum D.C. was particularly susceptible to fluazifop-P-butyl, an aryloxyphenoxypropionate herbicide, and the primary action site for the herbicide was shoot apical meristem, which is also the main site of indole-3-acetic acid (IAA) biosynthesis and action. Membrane lipid peroxidation caused by increasing levels of reactive oxygen species (ROS) was considered as an action mechanism of fluazifop-P-butyl in A. hispidum . To further clarify the ROS inducing mechanism of fluazifop-P-butyl in the plant, the interactions between fluazifop-P-butyl and auxin compounds IAA or 2,4-dichlorophenoxyacetic acid (2,4-D) were studied. Haloxyfop- P -methyl, an AOPP herbicide which is inactive on A. hispidum , was used for comparison. The results showed that the growth inhibition and malondialdehyde or H 2 O 2 increases induced by fluazifop-P-butyl on A. hispidum were reversed by IAA or 2,4-D. The IAA content was decreased but the contents of three IAA oxidation metabolites, indole-3-methanol, indole-3-aldehyde and indole-3-carboxylic acid were increased by fluazifop-P-butyl in A. hispidum , but not by haloxyfop- P -methyl. The growth of A. hispidum was not inhibited by three IAA oxidative compounds. Moreover, the activities of IAA oxidase and peroxidase were increased by fluazifop-P-butyl but not by haloxyfop- P -methyl, and the increase was reversed by IAA or 2,4-D. We suggest that there is an antagonistic effect between fluazifop-P-butyl and IAA or 2,4-D, and the IAA oxidation may be involved in the action mechanism of fluazifop-P-butyl in A. hispidum . [ABSTRACT FROM AUTHOR]

BACKGROUND The occurrence of herbicide-resistant weed biotypes is increasing and this report of an acetyl-CoA carboxylase (ACCase) inhibitor-resistant Digitaria sanguinalis L. Scop. from southwestern Ontario is another example. The identified weed escaped control in an onion and carrot rotation in which graminicides were used for several consecutive years. Our goal was to characterize the level and mechanism of resistance of the biotype. RESULTS The biotype was resistant to all five ACCase inhibitor herbicides tested. Gene-expression profiling was performed because none of the mutations known to confer resistance in the ACCase gene were detected. RNASeq and quantitative reverse-transcriptase PCR (qRT-PCR) results indicated that transcription of ACCase was 3.4-9.3 times higher in the resistant biotype than the susceptible biotype. ACCase gene copy number was determined by qPCR to be five to seven times higher in the resistant compared with the susceptible biotype. ACCase gene overexpression was directly related to the increase of the ACCase gene copy number. CONCLUSION Our results are consistent with the hypothesis that overexpression of the herbicide target gene ACCase confers resistance to the herbicide. This is the first reported case of target gene duplication conferring resistance to a herbicide other than glyphosate. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Acanthospermum hispidum DC, an Asteraceae weed species, was very susceptible to fluazifop-P-butyl, but tolerant to other aryloxyphenoxypropionate herbicides, such as haloxyfop- P -methyl. However, other Asteraceae weeds including Bidens pilosa were all tolerant to fluazifop-P-butyl. Membrane lipid peroxidation by increasing the levels of reactive oxygen species (ROS) was proposed as an action mechanism of fluazifop-P-butyl in A. hispidum . To further clarify the primordial action site of fluazifop-P-butyl in this species, the effects on chlorophyll fluorescence characteristics and cytohistology of apical meristems were studied. Chlorophyll fluorescence characteristics (CFC) in sensitive A. hispidum seedlings were markedly affected by 10 μM fluazifop-P-butyl, with the dark fluorescence yield (Fo), maximal fluorescence yield (Fm), maximal PS II quantum yield (Fv/Fm), effective photosystem II (PS II) quantum yield [Y(II)], and quantum yield of regulated energy dissipation [Y(NPQ)] declining, quantum yield of nonregulated energy dissipation [Y(NO)] rising, but these measures were not affected in Bidens pilosa . The effects of fluazifop-P-butyl on chlorophyll fluorescence properties were observed on the growing point before the mature leaves by about 4–6 h. Haloxyfop- P -methyl, a control herbicide, had no effects on CFC of either A. hispidum or B. pilosa . In addition, damage to apical meristem cells of A. hispidum was observed at 6 HAT prior to changes in chlorophyll fluorescence parameters suggesting that the primary action site of fluazifop-P-butyl in this species is in the apical meristem and the effects on CFC may be the results of secondary action. [ABSTRACT FROM AUTHOR]

Two field experiments were carried out at Faculty of Agriculture Farm, Al-Azhar University, Assiut governorate in 2014-2015 and 2015-2016 seasons to evaluate the efficiency of two post-emergence herbicides, i.e. Fusilade forte (fluazifop-p-butyl) and Goal (oxyfluorfen) on onion weed control at 30 and 60 days after treatment. Both herbicides were applied at their recommended and 3/4 recommended rates with and without spray tank additives, i.e. sodium lauryl ether sulphate and organosilicone adjuvants. The results showed that the tested adjuvants obviously increased the herbicidal efficiency of fusilade forte against grassy weeds and Goal against broad leave weeds. In most cases the maximum efficiency was achieved when both fusilade forte and Goal were applied at their recommended (187.5 and 180 g a.i/fed.) or 3/4 recommended (140.625 and 135 g a.i/feddan) rates, + organosilicone adjuvant at 0.1% v/v concentration without significant adverse effects in onion crop. [ABSTRACT FROM AUTHOR]

In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant Syngenta Crop Protection AG submitted a request to the competent national authority in Portugal to modify the existing maximum residue levels (MRL) for the active substance fluazifop-P in tomato, carrot and courgette. The data submitted in support of the request were found to be sufficient to derive MRL proposals for carrot and courgette. For tomato, data gaps were identified which precluded the derivation of MRL proposal. Adequate analytical methods for enforcement are available to control the residues of fluazifop-P in plant matrices under consideration. Based on the risk assessment results, EFSA concluded that the short-term and long-term intake of residues resulting from the use of fluazifop-P on carrots and courgettes according to the reported agricultural practices and the products of animal origin under consideration is unlikely to present a risk to consumer health. [ABSTRACT FROM AUTHOR]

Field investigation was carried out during rabi season of 2014-15 at Udaipur to evaluate the effect of different weed management practices on yield and nutrient uptake of mustard. The maximum seed yield was registered with two hand weeding (1955.25 kg ha-1) except weed free check and was at par with fluazifop-p-butyl 0.055 kg ha-1 10 DAS + hoeing 40 DAS and fenoxaprop-p-ethyl 0.075 kg ha-110 DAS + hoeing 40 DAS. The highest amount of total N, P and K (112.61, 25.31 and 76.90 kg ha-1, respectively) was removed by mustard in weed free treatment followed by two hand weeding while the lowest N, P and K with the values of 70.11, 16.05 and 51.86 kg ha-1, respectively was removed by weedy check followed by isoproturon 0.75 kg ha ha-1. Among the weed management practices, the total uptake of N, P and K by weeds was found significantly less in all the weed management practices as compared to weedy check(5.87, 0.86 and 5.51 kg ha-1, respectively). The least nutrient depletion by weeds was registered with the hand weeding twice (0.52, 0.08 and 0.49 kg ha-1, respectively) followed by fluazifop-p-butyl 0.055 kg ha-1 10 DAS + hoeing 40 DAS and fenoxaprop-p-ethyl 0.075 kg ha-110 DAS + hoeing 40 DAS. Use of post emergence herbicides of 'fop' group such as fluazifop-p-butyl, quizalofop-p-ethyl, fenoxaprop-p -ethyl (which are mostly used in soybean and groundnut crop) in indian mustard found most effective in controlling grassy weeds in early stage whereas at latterly, one hoeing 40 DAS was found effective in controlling grassy as well as broad leaved weeds under irrigated conditions. [ABSTRACT FROM AUTHOR]

Fluazifop-p-butyl (FPB) is a selective aryloxyphenoxypropionate herbicide. Its phytotoxicity mechanism involves inhibition of lipid biosynthesis, free-radical generation, and oxidative stress in vulnerable plants. This study evaluates the impact of orally administered FPB on selected tissues in non-target animal model. Twenty-four male wistar rats (160–180g) were randomized into groups (I–IV). Group-I served as control, while animals in groups II, III, and IV received FPB at 18.75, 37.5, and 75 mg/kg body weight/day p.o., respectively, for 21 days. FPB caused significant (p < 0.05) increase in plasma biomarkers of renal and hepatic function (urea, creatinine, bilirubin, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase) when compared to control. Significant reductions in testicular ascorbic acid, glutathione, and activities of glutathione-S transferase, superoxide dismutase, and catalase were observed in FPB-treated animals when compared to control, in a dose-dependent manner. This was accompanied by increased testicular lipid peroxidation in the treated groups. Furthermore, a significant decrease in testicular acid phosphatase and γ-glutamyl transferase activities was also observed in the FPB-treated groups in a dose-dependent manner compared to control. However, testicular lactate dehydrogenase activity was significantly increased in the FPB-treated rats when compared to control. Additionally, histopathological studies revealed severe interstitial oedema and congestion of testicular blood vessels in the FPB-treated groups. Overall, data from this study suggest that FPB induced hepatotoxicity, nephrotoxicity, and oxidative stress-mediated alteration of testicular functions in rat. [ABSTRACT FROM AUTHOR]

The enantioselective dissipation of the enantiomers of fluazifop-butyl in tomato, cucumber, pakchoi, rape and soil under field condition was investigated to elucidate the enantioselective environmental behaviours and chiral stability of the optical pure product. Fluazifop, the major chiral metabolite of fluazifop-butyl, was also detected. Fluazifop-butyl dissipated rapidly in the vegetables and soil with the half-lives of the enantiomers ranging from 1.62 to 2.84 days. Enantioselective degradations of fluazifop-butyl were found. In tomato and cucumber, S-fluazifop-butyl dissipated faster than R-enantiomer, while R-fluazifop-butyl showed a faster degradation in pakchoi, rape and soil. Fluazifop was found almost immediately after the application of fluazifop-butyl and had relatively longer persistent time. When the optical pure product fluazifop-P-butyl was applied, rapid degradation to R-fluazifop was found with half-lives from 1.24 to 2.28 days, and no S-fluazifop-butyl or S-fluazifop was detected showing the herbicidally active fluazifop-P-butyl and R-fluazifop were configurationally stable. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze the effect of herbicides tepraloxydim, fluazifopp- butyl and metribuzin on colony development and sporulation of some important fungi in in vitro and greenhouse conditions. At the end of the study, tepraloxydim at high dose of 2x10-3M prevented Rhizoctonia solani colony growth at the highest level with the rate of (88.93%). Tepraloxydim at 5x10-5M inhibited R. solani colony growth at the lowest level with the rate of (0.21%). However, the growth rate of Phoma destructiva could not be decreased at this low dose level, but increased the growth of colony by (1.29%). As a result of study, the colony development of R. solani in in vitro conditions was completely inhibited at high dose application (2x10-3M) of fluazifop-p-butyl. At low dose (5x10-5M) application of herbicide, the colony development of P. destructiva was decreased by (4.68%) at the lowest dose level, but increased colony development of Rhizopus stolonifer by (4.14%). Metribuzin prevented colony development of Rh. stolonifer at the highest dose level of 2x10-3 M by (63.47%) and the highest dose of application in in vitro conditions, It also prevented the development of Cladosporium fulvum at the lowest level (2.51%) when applied at 5x10-5 M. Tepraloxydim at above and below (50%) affected sporulation of fungal pathogens with Alternaria alternata most affected (1.2x102 spore/ml; 2.7x102 spore/ml) under greenhouse conditions. High dose (above concentrations of 50%) application of fluazifop-p-butyl mostly affected Stemphylium solani (1.6x102 spore/ml) in greenhouse conditions. A. alternata (3.0x102 spore/ml) was the mostly influenced pathogen for fungal sporulation at low dose (below 50%) application of fluazifop-p-butyl herbicide. High dose application of metribuzin mostly affected Fusarium solani and Rh. stolonifer in greenhouse. The total number of spores determined at the last count for F. solani and Rh. stolonifer was (2.5x102) spore/ml. The number of A. alternata spores at low dose application was (4.1x102) spore/ml. [ABSTRACT FROM AUTHOR]

Neste trabalho, objetivou-se avaliar os efeitos da mistura dos herbicidas fomesafen + fluazifop sobre a comunidade de artrópodes do solo cultivado com feijão nos sistemas plantio direto e convencional. O experimento foi realizado em Argissolo Vermelho-Amarelo distrófico de boa fertilidade, em Coimbra, MG. Duas semanas após o plantio foi aplicada a mistura comercial dos herbicidas fluazifop + fomesafen, denominada Robust®, na dose de 0,8 L ha-1; em cada sistema de cultivo foi mantida uma testemunha sem aplicação de herbicida. O delineamento experimental foi o de blocos casualizados, com cinco repetições. As populações de artrópodes do solo foram amostradas aos 1, 8, 21 e 42 dias após a aplicação do herbicida. Os dados foram submetidos à análise de variáveis canônicas (CVA), que é uma técnica de ordenação indireta que reduz a dimensionalidade do conjunto dos dados originais em um conjunto de variáveis que podem ser usadas para ilustrar graficamente as posições relativas e as orientações das médias das respostas da comunidade em cada tratamento sob comparação. As diferenças entre os tratamentos na abundância dos artrópodes selecionados foram determinadas pela análise de variância por medida repetida, considerando a data de amostragem como a medida repetida. A análise das variáveis canônicas CVA para os sistemas de plantio e aplicação de herbicida indicou diferenças na densidade de artrópodes coletados nos diferentes tratamentos estudados, considerando a composição e a abundância das espécies. Foram observadas, por meio do diagrama de ordenação, diferenças no conjunto de artrópodes do solo coletados nos dois sistemas de plantio. A aplicação dos herbicidas afetou a densidade dos artrópodes associados ao feijoeiro em ambos os sistemas de cultivo, com exceção do Solenopsis sp. O sistema de plantio afetou a densidade de todas as espécies estudadas.The aim of this research was to evaluate the effect of herbicide mixture (fomesafen + fluazifop) on the soil arthropod communities associated to the common bean in two cropping systems (conventional and no-tillage). The experiment was carried out on Red-yellow Podzol, in Coimbra, Minas Gerais, Brazil. The studied treatments in both cropping system were represented by the mixture of herbicide Robust® (fluazifop + fomesafen) (dosage of 0.8 L ha-1) applied two weeks after planting and control without herbicide application. A complete randomized block design with five replications was used in the experiment. The soil arthropod communities were sampled 1, 8, 21 and 42 days after herbicide application. The data were submitted to the canonical variate analysis (CVA). CVA is an indirect ordination technique that reduces the size of the original data set. The CVA techniques can be used to illustrate graphically the relative positions and the coordinates of the community's structure for each treatment. The differences between the treatments in the abundance of the selected arthropods had been determined by repeated measure analysis of variance considering the sampling data as repeated measure. The canonical variate analysis for cropping systems and herbicide application indicated differences between the arthropod densities in the different treatments considering the composition and the species abundance. In this study, differences in the set data of collected soil arthropods were observed through ordination diagrams under the two cropping systems. Herbicide application affected all arthropods associated to the common beans in both cropping systems, except Solenopsis sp. The cultivation system affected the densities of all species studied.

Com o objetivo de avaliar diferentes manejos de plantas daninhas no plantio direto da soja, cultivada sobre palha de milheto (manejada com rolo-faca ou glyphosate), foram realizados dois experimentos com dois cultivares de soja (Conquista e Celeste) e aplicação em pós-emergência da mistura formulada dos herbicidas fluazifop-p-butil + fomesafen (0, 100+125 e 200+250 g ha¹). Por meio da análise de variância conjunta dos experimentos, verificou-se predominância de diferentes espécies de plantas daninhas em função do manejo dado ao milheto, sendo a maior infestação destas verificada sob o manejo com rolo-faca associado à ausência de controle na cultura da soja. Há a possibilidade da redução da dose de fluazifop-p-butil + fomesafen para o controle de plantas daninhas na soja, desde que precedida da aplicação de glyphosate para formação da palha de milheto. Sob esta condição, verificou-se maior controle das espécies daninhas, em relação ao manejo mecânico (rolo-faca), resultando em maior produtividade da cultura, devido à maior quantidade de vagens por planta e de grãos por vagem.The aim of this study was to evaluate different types of management methods under soybean no-tillage cultivated over pearl millet straw (managed with cutting-roller or glyphosate). Two experiments were carried out with two soybean cultivars (Conquista and Celeste) and post-emergence application of the formulated mixture of the herbicides fluazifop-p-butyl + fomesafen (0, 100+125 and 200+250 g ha-1 ). Conjoined variance analysis of the experiments showed predominance of different weed species over pearl millet management with the greatest infestation of the former being verified under cutting-roller management associated to control absence in the soybean crop. The fluazifop-p-butyl + fomesafen dose may be reduced for weed control in soybean provided it is preceded by glyphosate application to form pearl millet straw. Under this condition, greater weed control was verified in relation to mechanic management (cutting-roller), resulting in greater crop yield, due to the greater amount of pod per plant and grain per pod.

O objetivo deste trabalho foi avaliar o crescimento das estirpes de Rhizobium tropici BR 322 e BR 520, utilizadas como inoculantes na cultura do feijoeiro no Brasil, em meio de cultura à base de manitol e extrato de levedura (YM) adicionado de diferentes herbicidas (bentazon, metolachlor, imazamox, fluazifop-p-butil, fomesafen e paraquat). Os herbicidas fluazifop-p-butil e fomesafen foram avaliados puros e em mistura comercial, em concentrações variando entre 0,0 e 49,23 mg L-1. O crescimento das estirpes de Rhizobium foi avaliado em espectrofotômetro ao longo de 100 horas de incubação, por meio da leitura da densidade ótica, a 560 nm, sendo, posteriormente, convertido em unidades formadoras de colônia por mL. Observou-se que o paraquat foi o herbicida com maior inibição do crescimento das estirpes avaliadas, seguido pela mistura comercial de fomesafen e fluazifop-p-butil. Para os demais herbicidas, a redução do crescimento não foi significativa. De modo geral, a estirpe BR 520 mostrou-se mais tolerante aos herbicidas testados, com exceção do paraquat. No ensaio de concentrações crescentes do fomesafen, isolado ou em mistura com fluazifop-p-butil, não foi possível determinar o I50 (concentração do herbicida que reduz em 50% o crescimento do rizóbio); a maior redução, de 31,1%, foi observada para a estirpe BR 322 na máxima concentração testada (49,23 mg L-1) da mistura comercial.This work aimed to evaluate the growth of Rhizobium tropici BR322 and BR 520 strains, used as inoculant on common bean in Brazil, in yeast extract manitol (YM) medium supplemented with different herbicides (bentazon, metolachlor, imazamox, fluazifop-p-butyl, fomesafen and paraquat). Fluazifop-p-butyl and fomesafen were evaluated pure and in a commercial mixture with concentration varying from 0.0 to 49.23 mg L-1. Cell growth was assessed by optic density readings in a spectrophotometer at 560 nm, being later converted to colony forming units per mL. Paraquat caused higher inhibition of cell growth, followed by the commercial mixture fomesafen and fluazifop-p-butyl. For the other herbicides, growth reduction was not significant. In general, BR 520 strain was more tolerant to the tested herbicides, except to paraquat. The herbicide concentration I50, (which decreased Rhizobium growth in 50%) could not be determined in the fomesafen concentrations tested, isolated or mixed to fluazifop-p-butyl. The highest reduction of 31.1% was observed in BR322 at the maximum tested concentration of the commercial mixture.

In intensely cultivated regions, it is crucial to have knowledge of the leaching potential related to pesticides in agricultural production. This is especially true in countries, like Denmark, that base its drinking water supply on untreated groundwater. Since fluazifop-P-butyl (FPB) is applied to control perennial and annual weed grasses in agricultural fields, the objective of this study was to evaluate leaching of its two degradation products – fluazifop-P (FP; free acid; (R)-2-(4-(5-trifluoromethyl-2-pyridyloxy)phenoxy)propionic acid) and TFMP (5-(trifluoromethyl)-2(1H)-pyridinone) – through an agricultural field consisting of loamy soil. Drainage and groundwater samples were collected over a five-year period following four spring/summer applications of FPB, and analysed for both FP and TFMP. FP was only detected once in groundwater, whereas TFMP within the first year after the first and fourth application was detected in concentrations exceeding the value of 0.1 μg L − 1 in 100% and 24% of the drainage samples and 9% and 14% of the groundwater samples, respectively. Detections of TFMP up to 18 months after application were obtained both in the drainage and groundwater. What differentiated the first and fourth FPB applications from the two others were heavy precipitation events within one week of FPB application, which resulted in rapid transport of TFMP through the discontinuities in the soil and contributed to relatively high TFMP detections in drainage and groundwater. This study indicated that pesticide degradates like TFMP, often being more soluble than the pesticide, have a relatively high leaching potential especially associated with heavy precipitation events shortly after the application. Hence, such pesticide degradates should like in Denmark be considered “relevant” meaning that the EU value for drinking water applies to them, having its leaching potential regulatory assessed based on high quality estimations of their persistence, and be exposed to an assessment of the risk to consumers of drinking contaminated groundwater. [ABSTRACT FROM AUTHOR]

In accordance with Article 6 of Regulation ( EC) No 396/2005, the evaluating Member State ( EMS), Austria, compiled an application to modify the existing maximum residue level ( MRL) for the active substance fluazifop-P in pumpkins seeds. To accommodate for the intended use of fluazifop-P, Austria proposed to set the MRL for pumpkin seed at the value of 5 mg/kg. Austria drafted an evaluation report in accordance with Article 8 of Regulation ( EC) No 396/2005, which was submitted to the European Commission and forwarded to EFSA. According to EFSA, the data are sufficient to derive the MRL proposal of 5 mg/kg for the proposed use on pumpkin seeds. Adequate analytical enforcement methods are available to control the residues of fluazifop-P on pumpkin seeds. Based on the risk assessment results, EFSA concludes that the proposed use of fluazifop-P on pumpkin seeds will not result in a consumer exposure exceeding the toxicological reference values and therefore is unlikely to pose a consumer health risk. [ABSTRACT FROM AUTHOR]

The stereoselective degradation and transformation of the enantiomers of the herbicide fluazifop-butyl in soil and water were studied to investigate the environmental behavior and chiral stability of the optical pure product. Its main chiral metabolite fluazifop was also monitored. LC/MS/MS with Chiralpak IC chiral column was used to separate the enantiomers of fluazifop-butyl and fluazifop. Validated enantioselective residue analysis methods were established with recoveries ranging from 77.1 to 115.4% and RSDs from 0.85 to 8.9% for the enantiomers. It was found the dissipation of fluazifop-butyl was rapid in the three studied soils (Beijing, Harbin and Anhui soil), and the degradation half-lives of the enantiomers ranged from 0.136 to 2.7 d. Enantioselective degradations were found in two soils. In Beijing soil, R-fluazifop-butyl was preferentially degraded leading to relative enrichment of S-enantiomer, but in Anhui soil, S-fluazifop-butyl dissipated faster. There was no conversion of the R-fluazifop-butyl into S-fluazifop-butyl or vice versa in the soils. The formation of fluazifop in the soils was rapidly accompanied with the fast degradation of fluazifop-butyl, and the enantioselectivity and the transformation of S-fluazifop to R-fluazifop were found. The degradation of fluazifop-butyl in water was also quick, with half-lives of the enantiomers ranging from 0.34 to 2.52 d, and there was no significant enantioselectivity of the degradation of fluazifop-butyl and the formation of fluazifop. The effects of pH on the degradation showed fluazifop-butyl enantiomers degraded faster in alkaline conditions. This study showed an evidence of enantioselective behavior and enantiomerization of the chiral herbicide fluazifop-butyl. [ABSTRACT FROM AUTHOR]

Objetivou-se neste trabalho avaliar a interação competitiva de Brachiaria brizantha e B. plantaginea sob doses reduzidas de fluazifop-p-butil, aplicadas em diferentes épocas. O delineamento experimental adotado foi o de blocos casualizados, com quatro repetições, seguindo o arranjo fatorial 6x3, com seis doses de fluazifop-p-butil (7,5; 12,5; 18,75; 31,25; 43,75 e 62,5 g ha-1), aplicadas em três épocas (14, 24 e 34 dias após a emergência das plantas - DAE), mais uma testemunha sem herbicida. A maior dose utilizada correspondeu a 33% da dose recomendada para a cultura da soja (187,5 g ha-1). A avaliação dos tratamentos foi realizada aos 53 DAE das espécies. As plantas foram desmembradas em folhas e colmos, determinando-se a biomassa seca das partes. Foram também avaliados a área foliar, o número e o comprimento dos colmos. B. plantaginea foi mais suscetível ao fluazifop-p-butil do que B. brizantha. A dose de 25 g ha-1 do herbicida, aplicada aos 14 DAE, permitiu máximo acúmulo de biomassa seca de B. brizantha e controlou satisfatoriamente B. plantaginea. Aplicando-se nessa mesma época a dose de 62,5 g ha-1 de fluazifop-p-butil, as duas espécies foram controladas. Quanto ao efeito de épocas de aplicação, quando utilizadas doses reduzidas, que não visam o controle pleno das espécies, plantas mais jovens de B. brizantha e B. plantaginea apresentaram melhor capacidade de recuperação.The objective of this work was to evaluate the competitive interaction between Brachiaria brizantha and B. plantaginea under reduced rates of fluazifop-p-butyl and different application timings. The experimental design was a randomized complete block, with four replications, arranged in a 6 x 3 factorial, consisting of six doses of fluazifop-p-butyl (7,5; 12,5; 18,75; 31,25; 43,75 and 62,5 g ha-1), applied in three times (14, 24 and 34 days after plant emergence - DAE) and a control without herbicide. The highest dose applied corresponded to 33% of the recommended dose for soybean (187,5 g ha-1). The evaluation of the treatments was accomplished 53 DAE. The plants were grouped into leaves and stems, and their dry biomass obtained. Leaf area, stem number and stem length of both species were determined. B. plantaginea was more susceptible to fluazifop-p-butyl than B. brizantha. It was observed that 25 g ha-1 of fluazifop-p-butyl, applied at 14 DAE allowed maximum B. brizantha dry biomass accumulation and satisfactory control of B. plantaginea. In this application timing the dose of 62.5 g ha-1 controlled both species. Regarding application timing, when treated with reduced doses not intended to achieve full species control, young plants of B. brizantha and B. Plantaginea presented better recovery ability.

Possibilities of herbicide applications to the self-heal (Prunella vulgaris L.) growth were tested in 1997-1998. Experiments showed that the application of pre-emergence herbicides in the Prunella vulgaris L. growth was efficient when 3 l/ha ofherbicide with 500 g/lisoproturon as an active ingredient were used. Herbicide applications had no influence on the emergence rate of direct seeding. Among the post-emergence herbicides it is possible to use glyphosate-IPA in 50% concentration by the wick applicator to Elytrigia repens (L.) Nevski. The results of these experiments can be used as a basis for testing the herbicide biological efficacy in the framework of minority indications for cultivated medicinal plants. .

A integração de certas práticas de manejo ao controle químico de plantas daninhas pode permitir a redução da dose do herbicida a ser aplicado, sem alterar significativamente os níveis de controle das plantas daninhas e rendimento de grãos de soja. Dessa forma, o objetivo do presente trabalho foi de avaliar a redução da dose recomendada da mistura formulada dos herbicidas fluazifop-p-butyl + fomesafen aplicados em condições de pós-emergência das palntas daninhas, associada à variação no espaçamento entre linhas da cultura de soja, sobre o controle de papuã (Brachiaria plantaginea) e o rendimento final de grãos da cultura. O experimento foi realizado na EEA/UFRGS, em Eldorado do Sul-RS, na estação de crescimento de 1997/98. O cultivar de soja testado foi o BR 16, em semeadura direta. Como tratamentos, utilizaram-se três espaçamentos entre linhas (20, 40 e 60 cm) e cinco doses do herbicida [fluazifop-p-butyl (200 g L-1) + fomesafen (250 g L-1)], aplicado na dose recomendada comercialmente de 1,0 L ha-1 (100%) e com reduções da dose (75, 50 e 25% da dose recomendada), mais a testemunha. Avaliou-se visualmente o controle de papuã aos 8 e 17 dias após as aplicações do herbicida, bem como a fitomassa seca de papuã e o rendimento de grãos da cultura. Os resultados evidenciaram que, para infestação moderada de papuã, o espaçamento entre linhas não tem efeito sobre o seu controle quando o herbicida é utilizado na dose recomendada. Para aplicações tardias, o espaçamento de 40 cm permite reduzir a dose do herbicida em até 50% sem afetar o controle de papuã e em 75% sem diminuir o rendimento de grãos da soja. A redução na dose do herbicida está condicionada à época de aplicação e ao espaçamento entre linhas; com espaçamentos reduzidos, é importante que as aplicações sejam feitas precocemente, a fim de garantir que quantidade suficiente de produto atinja as plantas daninhas.Integration of certain crop management practices with chemical weed control could allow a rate reduction of the herbicide to be applied, without significant changes in weed control levels and soybean grain yields. This research aimed to evaluate reduction in the recommended rate of a formulated mixture of fluazifop-p-butyl plus fomesafen, associated with reduction in soybean row width, on alexandergrass (Brachiaria plantaginea) control and crop grain yield. The experiment was conducted at EEA/UFRGS, Eldorado do Sul-RS, during the growing season of 1997/98. Soybean cultivar tested was BR 16, sowed under a no-till system. The treatments consisted of three row widths (20, 40 and 60 cm), and five rates of the herbicide mixture [fluazifop-p-butyl (200 g L-1) + fomesafen (250 g L¹)], applied at the recommended rate of 1.0 L ha-1 (100%) and reduced rates (75, 50, and 25% of the recommended rate) plus a check. Alexandergrass control was visually evaluated at 8 and 17 days after herbicide applications, by obtaining its dry matter weight, as well as the soybean grain yield. The results showed that, for a moderate alexandergrass infestation, soybean row width does not affect weed control when the herbicide is sprayed at the recommended rate. For late herbicide applications, 40 cm row width allows a reduction of herbicide rate up to 50%, without affecting alexandergrass control and a decrease up to 75% of the herbicide rate, without reducing soybean grain yield; reduction of herbicide rate is conditioned to application time and row width used; with reduced row widths application must be performed earlier so that a sufficient amount of the product reaches the weeds.

A bstract According to Article 12 of Regulation (EC) No 396/2005, the European Food Safety Authority (EFSA) has reviewed the maximum residue levels (MRLs) currently established at European level for the pesticide active substance fluazifop-P. In order to assess the occurrence of fluazifop-P residues in plants, processed commodities, rotational crops and livestock, EFSA considered the conclusions derived in the framework of Directive 91/414/EEC as well as the import tolerances and European authorisations reported by Member States (incl. the supporting residues data). Based on the assessment of the available data, MRL proposals were derived and a consumer risk assessment was carried out. Some information required by the regulatory framework was found to be missing and a possible acute risk to consumers was identified. Hence, the consumer risk assessment is considered indicative only, some MRL proposals derived by EFSA still require further consideration by risk managers and measures for reduction of the consumer exposure should also be considered. [ABSTRACT FROM AUTHOR]