Pendimethalin In Soil Research Articles

Dissipation kinetics and residues of pendimethalin in soil, straw and grain of rainy season greengram

Dissipation kinetics and residues of pendimethalin in soil, straw and grain of rainy season greengram

Effect of repeated atrazine and pendimethalin application on their bound residues in long term fertilized soil of semi-arid tropic region in India

Repeated and long term application of same herbicides forms bound residues in soil and becomes point source of pollution over a period of time and harms the soil microorganisms. Among the different herbicides, the atrazine and pendimethalin is widely and repeatedly used molecule in maize and sunflower cultivation for weed control, respectively. Hence the present study was undertaken to investigate the bound residue of the applied herbicides in soil under long term fertilized condition with varied nutrient sources since 1909 in North-Western agro-climatic zone of Tamil Nadu under the semi-arid tropic region of India. Soil samples were collected at the time of maize and sunflower harvest and analysed for the bound fraction of atrazine and pendimethalin compounds respectively. The results showed that the repeated application of these herbicides at recommended dose formed a considerable amount of non-extractable bound residues in soil. While the bound fraction of parent atrazine was found below detectable limit, pendimethalin was at a quantifiable level in the soil irrespective of fertilization sources. However the bound form of atrazine metabolites, namely Des ethyl Deisopropyl atrazine (DEDIA) and Hydroxy atrazine (HA) was extracted from the maize cultivated soil. Bound forms of HA (4.34%) and DEDIA (3.43%) and pendimethalin (3.14%)to the applied quantity were witnessed at a higher amount in control plot than the fertilized plots. The omission of any one major nutrient recorded elevated DEDIA bound form than the HA fraction. The non-extractable bound residues of both the herbicides were detected at different proportions according to the herbicide nature, sources of fertilization and the crops cultivated in the soil. The fraction of bound form of atrazine metabolites was detected at higher level than the pendimethalin in soil. The present study revealed that the bound residues of atrazine, its metabolites and pendimethalin can be mineralized into the soil solution and bio-augmented over a period of time under the conditions of repeated application. Hence the remobilization of bound residues of these herbicides must be considered while gauging the environmental hazard and effect on non-target organisms.

Fate of pendimethalin in soil and characterization of non-extractable residues (NER)

One important route of degradation of herbicide pendimethalin in soil leads to formation of non-extractable residues (NER). To investigate NER nature (irreversibly, chemically bound, including possible biogenic NER, or strongly sorbed and entrapped) residues of 14C-labelled pendimethalin in soil were investigated after conventional extraction with organic solvents by silylation. After 400 days of incubation, 32.0% of applied radioactivity (AR) was transformed into NER, 39.9% AR remained extractable. Mineralization reached 26.2% AR. Additionally, 14C-pendimethalin was incubated in soil amended with compost for 217 days to investigate the influence of organic amendments on NER formation. NER amounted to 37.8% AR, with 57.9% AR remaining extractable. Mineralization was negligible (1.4% AR). For all sampling times only low amounts of radioactivity were entrapped (<5% AR) in soil without compost amendment. Pendimethalin was present only in trace amounts (ca. 0.4% AR), other released residues consisted of undefined fractions (sum ≈2% AR). In soil amended with compost, silylation overall resulted in release of higher amounts of radioactivity (19% AR). Addition of compost led to an increase in potential entrapment and sorption sites for pendimethalin, forming higher amounts of strongly sorbed, entrapped residues. Furthermore, potential release of non-extractable pendimethalin residues was investigated by incubation of solvent-extracted soil (without compost amendment) mixed with fresh soil for additional 3 months. NER were partly mineralized (7% AR) and 20% became extractable with organic solvents. However, no pendimethalin or any known metabolites were found.It can be concluded that no parent pendimethalin was found and NER of pendimethalin in soil are mainly formed by covalent binding to organic matrix with only low potential of remobilization under natural conditions.

Dissipation of Pendimethalin in Soil Under Direct Seeded and Transplanted Rice Field.

The dissipation of pendimethalin applied in direct seeded rice (DSR) and transplanted rice (TPR) field at 1.0 and 2.0kg a.i. ha-1 followed biphasic first order kinetics (R2 > 0.91) and was comparatively faster under flooded TPR than DSR. The half-life (DT50) of pendimethalin in the soil ranged from 2.22 to 2.80days in the initial phase and 23.51 to 24.66days in the final phase in TPR for both application rates. However in DSR, DT50 varied from 3.67 to 4.35days in the initial phase and 34.19 to 34.99days in the final phase. Residues of pendimethalin in soil samples analyzed by HPLC and GC-MS/MS were below the detection limit (< 0.003µgg-1) for both the application rates in DSR and TPR whereas 0.003-0.009µgg-1 and 0.003-0.008µgg-1 residues of pendimethalin were found in rice grain and straw samples, respectively.

Natural biochar effect on sorption–desorption and mobility of diclosulam and pendimethalin in soil

The amendment of anthropogenic soils with natural biochar (without pyrolysis process) presents several environmental and agronomic benefits. However, there is little information available on the interaction of natural biochar with the herbicides applied directly into the soil. To address this knowledge gap, the influence of natural biochar on the sorption–desorption and mobility of diclosulam and pendimethalin herbicides in an agricultural soil was evaluated. The biochar was extracted from the profile of an Oxisol and post-dates the Holocene. The Ultisol-Typic Hapludalf used in this study was amended with natural biochar at rates of 0 (control), 0.1, 0.5 and 1.0% (m m−1). The 14C-diclosulam and 14C-pendimethalin showed specific activities of 0.002587 and 5.55 MBq mg−1, respectively. The sorption–desorption process was assessed by batch–equilibrium experiments. Liquid scintillation counting and soil thin-layer chromatography were used to determine herbicides adsorption and mobility. Application of natural biochar slightly increased the linear sorption coefficient (Kd) of each herbicide (from 0.22 to 0.50 L kg−1 for diclosulam, and from 25.55 and 37.81 L kg−1 for pendimethalin) in the soil, and the corresponding sorption percentages were 18.53–34.14% and 96.22–97.42%, respectively. However, the soil amendment did not alter the mobility of either herbicide, with retention factor (Rf) values of ~0.99 and 0.20 for diclosulam and pendimethalin, respectively, regardless of the natural biochar amount. Therefore, the presence of biochar in soil may not interfere with the bioavailability of diclosulam and pendimethalin in weed control under field conditions.

Effect of repeated application of pendimethalin on its persistence and dissipation kinetics in soil under field and laboratory conditions

ABSTRACTThe repeated application of herbicide can alter its persistence in the environment. In India, wheat fields are exposed to herbicide application at least once in the cropping season. The present study investigated the dissipation behavior of pendimethalin applied annually to a wheat field over four cropping seasons from 2012 to 2016. The dissipation studies were also conducted under laboratory conditions during 2015–2016. Pendimethalin from soil and wheat grain samples was extracted using matrix solid-phase dispersion and quantified using high-performance liquid chromatography and gas chromatography–tandem mass spectrometry. The average recoveries of pendimethalin from soil and crop produce ranged from 81.3% to 103.1%. The half-life of pendimethalin ranged from 20.9 to 31.3 days and 9.4 to 60.2 days under field and laboratory conditions, respectively. Dissipation of pendimethalin varied significantly over the years under field conditions and was comparatively faster than under laboratory conditions. On the other hand, non-significant variation in the dissipation of pendimethalin in soils under laboratory conditions was observed. The residues of pendimethalin in crop produce at harvest were below the maximum residue limit set by EPA.

Occurrence and distribution of trifluralin, ethalfluralin, and pendimethalin in soils used for long-term intensive cotton cultivation in central Greece

ABSTRACTIn the present study, a soil monitoring program was undertaken in Greek cotton cultivated areas in 2012. Twenty-seven soil samples were collected from the entire Thessaly plain in early summer of 2012, corresponding to approximately three months (current use of pendimethalin), up to one year (for the banned ethalfluralin), and three years (for the also banned trifluralin), after the last dinitroaniline application. Low but not negligible levels of dinitroanilines were detected, ranging from 0.01 to 0.21 μg g−1 d.w. for trifluralin and 0.01–0.048 μg g−1 d.w. for pendimethalin, respectively. Trifluralin was the herbicide most frequently detected (44.4%). The high historic application of trifluralin and its high persistence and accumulation potential is in line with the abundance of the detected residues. The present data indicate that soil samples contain extractable residues of banned trifluralin, but based on the comparison of the theoretical PECplateau for trifluralin (0.277 µg g−1) and the maximum Measured Environmental Concentration, it was concluded that the detected residues should be attributed to previous years’ application. The latter suggested the need for continual monitoring of the dinitroaniline family of pesticides, including the banned substances, aiming thus to an improved environmental profile for agricultural areas.

Dissipation kinetics and residues analysis of pendimethalin in soil and maize under field conditions

Herbicides play an important role in the production of crops, but their residues may cause numerous human/environmental problems. Dissipation kinetics of pendimethalin and residues in soil, maize straw and cobs in winter maize under field conditions were studied by gas chromatograph-electron capture detector (GC-ECD). Dissipation followed the first order kinetics and accounted by a biphasic pattern. The half-life for initial phase and later phase was 11.70 and 34.13 days for recommended and 9.19 and 46.81 days for double dose, respectively. Percent recovery from cobs, straw and soil samples varied from 76.2-88.5, 76.6-84.4, and 85.0-89.5%. The limit of quantification was 0.001 µg/g of sample. At harvest pendimethalin residues were below detectable limit in soil, maize cobs and maize plant at both application rates (1 and 2 kg/ha). Pendimethalin is safe for use and does not appear to pose any health hazard to consumers or harm to the environment.

Dissipation of Pendimethalin in Organic Soils in Florida

Understanding the persistence of PRE-applied pendimethalin is important in determining timing of subsequent weed management programs in sugarcane on organic soils in the Everglades Agricultural Area (EAA). Dissipation of oil- and water-based pendimethalin formulations applied PRE at 2, 4, and 8 kg ai ha−1were compared in 2011 and 2012 on organic soils in the EAA. The rate of dissipation of both formulations was very similar. Both formulations had an initial rapid rate of dissipation followed by a slower rate of dissipation. However, the initial amount of pendimethalin in the soil was higher with the water-based compared to the oil-based formulation, most likely because of the lower volatility of the water-based formulation. The half-lives (DT50s) of the oil-based formulation were 32, 18, and 10 d and 8, 8, and 12 d at 2, 4, and 8 kg ha−1, respectively, in 2011 and 2012, respectively. The DT50s of the water-based formulation were 20, 13, and 10 d and 12, 12, and 14 d at 2, 4, and 8 kg ha−1, respectively in 2011 and 2012, respectively. These DT50values were attributed to low soil water content as well as the absence of incorporation following application. Our results suggest that dissipation of pendimethalin is rapid on organic soils irrespective of the formulation when applied under dry soil conditions with no incorporation into the soil.

English

One strain of microorganisms was isolated from soil previously treated with pendimethalin using enrichment technique and identified using 16S rDNA as Pseudomonas putida (E15). The effect of pH and temperature on the growth ability of the tested strain was investigated. The results show that the optimum pH and temperature for the growth of pendimethalin dissipating strain were 7 and 30&deg;C, respectively. P. putida was used to dissipate pendimethalin from mineral liquid medium with half-live of 5.46 days. Pendimethalin half-live was 51.9 days in untreated mineral liquid medium. P. putida and compost were also evaluated for detoxification of pendimethalin in clay soil. P. putida and compost were effective in pendimethalin dissipation in soil with half-live of 4.67 and 5 days, respectively. Pendimethalin half-live was 62.43 days in untreated soil. Pendimethalin treatment affected analysis of the microbial population growing in P. putida or compost treating soil leachates showed an overall increase in the population of microorganisms. There is no toxicity of pendimethalin detected in soil on cucumber plants after treatment with P. putida or compost. Pendimethalin significantly decreased germination and increased cucumber seedlings mortality rate. P. putida and compost treatments increased the growth parameters. Moreover, no significant difference was observed in the most growth parameters between P. putida and compost treatments. Abnormal development of xylem tissue was observed in pendimethalin contaminated soil as a result of phytotoxicity. The results suggest that bioremediation by P. putida and compost was considered to be effective method for detoxification of pendimethalin in soil. &nbsp; Key words: Pendimethalin, soil, biodegradation, phytotoxicity, seedling mortality. &nbsp

Tolerância de mamoneira ao herbicida pendimethalin em solos com diferentes capacidades de adsorção

A mamoneira é uma espécie de crescimento inicial lento. A ausência de herbicidas registrados para esta cultura, ainda é fator limitante para sua expansão; assim, objetivou-se, com este trabalho, avaliar a tolerância da mamoneira ao herbicida pendimethalin em solos com diferentes capacidades de adsorção. O experimento foi conduzido em casa de vegetação, em delineamento inteiramente casualizado com cinco repetições e consistiu em uma combinação fatorial de oito doses do herbicida pendimethalin aplicado em pré-emergência (0; 187,5; 375; 750; 1.500; 3.000; 6.000 e 12.000 g ha-1 i.a.) e quatro tipos de substrato, sendo três solos de textura: franco-argilo-arenosa, franco-argilosa e franco-arenosa, além do substrato arenoso. Aos 22 dias após a semeadura determinaram-se as variáveis altura de plantas, área foliar, massa fresca e seca da parte aérea, volume e massa seca do sistema radicular. Concluiu-se que a dose do herbicida pendimethalin tolerado pela mamoneira é influenciada pela capacidade de adsorção do solo. O herbicida mostrou-se seletivo à cultura não ocasionando redução do crescimento nas doses utilizadas para controle de plantas daninhas.

Dissipation of Pendimethalin in Soil and Its Residues in Chickpea (Cicer arietinum L.) Under Field Conditions

Disappearance of pendimethalin in the soil of chickpea (Cicer arietinum L.) at 0-110 days, and terminal residues in plant samples have been studied under field conditions. Pendimethalin was applied as pre-emergence herbicide at 750, 350 and 180 g a.i. ha(-1) in winter, in chickpea crop. The dissipation of pendimethalin in the chickpea field soil conditions followed first order kinetics showing a half-life of 11.23 days averaged over all doses. Low pendimethalin residues were found in plant samples. 0.025, 0.015, <0.001 μg g(-1) residues of pendimethalin were found in grains at 750, 350 and 185 g a.i. ha(-1) treatments, respectively. Much lower pendimethalin residues were found in straw viz. 0.015 to <0.001 μg g(-1) at 750, 350 and 185 g a.i. ha(-1) treatments, respectively.

The effects of pesticide mixtures on degradation of pendimethalin in soils

Most agronomic situations involve a sequence of herbicide, fungicide, and insecticide application. On the other hand, use of pesticidal combinations has become a standard practice in the production of many agricultural crops. One of the most important processes influencing the behavior of a pesticide in the environment is its degradation in soil. It is known that due to several pesticide applications in one vegetation season, the pesticide may be present in mixtures with other pesticides or xenobiotics in soil. This study examines the role which a mixture of chemicals plays in pesticide degradation. The influence of other pesticides on the rate of pendimethalin (PDM) degradation in soil was measured in controlled conditions. Mixtures of PDM with mancozeb or mancozeb and thiamethoxam significantly influenced the degradation of pendimethalin under controlled conditions. The second type of mixtures, with metribuzin or thiamethoxam, did not affect the behavior of pendimethalin in soil. Also, we determined the influence of water content on the rate of pendimethalin degradation alone in two soils and compared it to the rate in three pesticide mixtures. We compared two equations to evaluate the predictors of the rate of herbicide dissipation in soil: the first-order kinetic and the non-linear empirical models. We used the non-linear empirical model assuming that the degradation rate of a herbicide in soil is proportional to the difference of the observed concentration of herbicide in soil at time and concentration of herbicide in the last day of measurement.

Quantification of pendimethalin in soil and garlic samples by microwave-assisted solvent extraction and HPLC method

A method for the residual pendimethalin in soil and vegetable samples was developed. The method is based on extraction of pendimethalin from samples using microwave-assisted solvent extraction (MASE) with acetone, ethanol, and water as extraction solvent. Extracted pendimethalin samples were analyzed by high-performance liquid chromatography with ultraviolet detector at 240 nm. The MASE parameters, temperature, heating time, and solvent types were optimized with the feasibility of MASE application in the determination of pendimethalin extraction efficiency of pendimethalin from soil and vegetable samples. The maximum temperature that can be used during the heating for MASE is 60°C, where the recovery percentages reached 97%. Linearity for pendimethalin was found in the range of 2-20 μg mL(-1) with limits of detection and limits of quantification of 0.059 and 0.17 μg mL(-1), respectively.

Enhanced Dissipation of Oxyfluorfen, Ethalfluralin, Trifluralin, Propyzamide, and Pendimethalin in Soil by Solarization and Biosolarization

This study was conducted to assess the effects of solarization and biosolarization on the degradation of oxyfluorfen, ethalfluralin, trifluralin, propyzamide, and pendimethalin. The experimental design consisted of 17 L pots filled with clay-loam soil, which were contaminated with the studied herbicides. Then, soil disinfection treatments were applied during the summer season, including a control without disinfection (C), solarization (S), and biosolarization (BS). Soil from five pots per treatment was sampled periodically up to 90 days. Herbicide dissipation rates were higher in both S and BS treatments with regard to the control. Similar dissipation rates were observed under S and BS for most of the herbicides studied, except oxyfluorfen and pendimethalin, which were degraded to a greater extent in the BS than in the S treatment. The obtained results showed that both solarization and biosolarization can be considered, in addition to soil disinfection techniques, such as bioremediation tools for herbicide-polluted soils.

DISAPPEARANCE OF PENDIMETHALIN IN SOIL AND ITS RESIDUE IN RIPE FENNEL

Disappearance of pendimethalin in soil, a herbicide widely used for control of weeds on vegetable crops, has been studied. A simple and rapid multiresidue analytical procedure for the quantifi cation of the substance has been applied using a Hewlett Packard 5890A gas chromatograph, equipped with a nitrogen – phosphorus detector (GC-NPD). Disappearance trend followed fi rst order kinetics seemed to be the best approximation. The average pendimethalin residues have decreased according to equations: y = 0.236e-0.0115x (exponential) and y = -0.0018x + 0.226 (linear) with excellent coeffi cient of determination in both cases. Half-lives obtained from those equations were 60 and 62 days, respectively. Low pendimethalin residue in plants indicate that fresh fennel may be used as additive in baby food. On the other hand, the experimental results indicate that pendimethalin is quite stable compound and may cause problems with follow-up crops.

Dissipation of Pendimethalin in the Garlic (Allium sativum L.) under Subtropical Condition

Pendimethalin is the common name of N-(1-ethylpropyl)3,4-dimethyl-2,6-dinitrobenzenamine, a dinitroaniline herbicide that is used widely for selective control of most annual grasses and many annual broad-leaved weeds in crop fields such as rice, peanut, soybean, cabbage, garlic, onion, radish, tomato, pea, and tobacco in Taiwan. Field dissipation studies have revealed that pendimethalin is persistent (Walker and Bond, 1977; Zimdalh et al., 1984; Smith et al., 1995). Walker and Bond (1977) found that the half-life of pendimethalin in a sandy soil, with the moisture at 75% field capacity, is 98 days at 30 C and 409 days at 10 C. The half-life of pendimethalin in a sandy loam soil treated with 1.5 kg a.i./ha in wheat crops in the tropical climate of India ranges from 58 to 63 days (Kulshrestha and Yaduraju, 1987). Singh et al. (2002) have also found that the dissipation of pendimethalin in soil has a half-life of 74 days. Pendimethalin degrades more rapidly in anaerobic soil than in aerobic soil conditions. The T1/2 values of pendimethalin in anaerobic and aerobic soils are 33 and 52 days, respectively (Kulshrestha and Singh, 1992). However, field studies conducted in Greece show that DT50 of pendimethalin in onion fields range from 37 to 39 days (Nicholas and George, 1998). Furthermore, the half-lives of Pendimethalin in cabbage fields with the application rates of 1 kg a.i./ha and 2 kg a.i./ha are 15 and 17 days, respectively (Arora and Gopal, 2004). Besides persistence, the mobility and leaching ability are also important in the environmental study of pesticides. Pendimethalin is classified as a non-leaching compound (Cooper et al., 1994). The field persistence of residues of pendimethalin in soil and garlic (Allium sativum L.) plants in the subtropical conditions of Taiwan have not been examined. This study measures the dissipation and mobility of pendimethalin in a garlic field by the model ecosystem. Additionally, the movement and degradation of pendimethalin in garlic plants are investigated.

Bacillus sp. MS202에 의한 Dinitroaniline계 제초제인 Pendimethalin의 부분환원

The persistence of pendimethalin in soil and ground water has an injurious effect on ecosystem. Pendimethalin-degrading bacterium was isolated from Masan, Gyeongnam province and temporarily identified as Bacillus sp. MS202 by the analysis of API CHB50, kit, FAME, and 16S rDNA sequence. from the analysis of pnedimethalin metabolite using TLC, GC, and GC-MS, we found that the degradation of pendimethalin by Bacillus sp. MS202 did not result in the dealkylated form, but the formation of the reduced compound, 6-amino-2-nitro-N(1-ethylpropyl)-3,4-xylidine or 2- amino-6-nitro-N(1-ethylpropyl)-3,4-xylidine.

Persistence of chlorpyrifos, fenamiphos, chlorothalonil, and pendimethalin in soil and their effects on soil microbial characteristics.

Persistence of chlorpyrifos, fenamiphos, chlorothalonil, and pendimethalin in soil and their effects on soil microbial characteristics.

Effect of cropping cycles and repeated herbicide applications on the degradation of diclofop‐methyl, bentazone, diuron, isoproturon and pendimethalin in soil

Effect of cropping cycles and repeated herbicide applications on the degradation of diclofop‐methyl, bentazone, diuron, isoproturon and pendimethalin in soil