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Open Access
Synthesis of potent herbicidal organic compounds using ionic liquid and heterogeneous catalytic systems
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-01) Verma, Shivani; Kasana, Virendra
Synthesis of five series of compounds namely _-phosphonomalonates using tetrabutylammonium bromide (TBAB) catalyst, naphthopyrans using novel nano-SiO2@Si(CH2)3@[tetrabutylammonium][valinate] catalyst, octahydroquinazolinone-1,3-dicarbaldehydes using novel tetrabutylammonium prolinate catalyst, small organic acid ionic liquids and cinnamic acid ionic liquids by acid-base neutralization method were carried out and screened for their herbicidal activity against Raphanus sativus (raddish) seeds at different concentrations (0.005M, 0.01M and 0.02M). Mild reaction conditions was applied for synthesis of _-phosphonomalonate, naphthopyran and octahydroquinazolinone-1,3-dicarbaldehyde derivatives affording these compounds in good to excellent yields. All the synthesized derivatives were docked with acetohydroxy acid synthase (AHAS) protein available on RSPDB data bank via molecular docking studies. The prepared catalyst was confirmed by 1HNMR, FT-IR, SEM, TEM and XRD techniques. The structure of compounds was elucidated using FT-IR, 1HNMR, 13CNMR and HR-MS spectral techniques.
Open Access
Comparative study on phytochemical, antioxidant, antimicrobial, insecticidal activity of Citrus sinensis and Citrus reticulate
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-05) Sanwal, Yamini; Tandon, Shishir
Citrus reticulata (kinnow) and Citrus sinensis (orange) were collected from local market of Pantnagar, The essential oil was isolated from the fruit peel by hydrodistillation using Clevenger apparatus. Essential oils were analysed for their chemical composition by GC-MS. Essential oils were tested against Callosobruchus chinensis and Tribolium castaneum for their contact, repellent, fumigant and ovipositional activities. Essential oils were also screened for their antimicrobial activity against two plant pathogenic fungi viz; Fusarium oxysporum and Rhizoctonia solani and Pseudomonas aureginosa bacteria. Antioxidant assay by different methods viz; reducing power activity, chelating activity of Fe2+, free radical scavenging activities were also studied for both the oils. Chemical composition of Citrus reticulata essential oil revealed D-limonene (94.64%), myrcene (1.72%) and n-caprylaldehyde (1.29%) as a major compounds. However, Citrus sinensis essential oil had D-limonene (86.36%) _-terpinyl acetate (4.22%), p-bis (trimethylsilyl) benzene (1.55%) and cis-oleic acid (1.10%) as a major compounds. The bioassay on insecticidal activity (contact, fumigant, repellent, and ovipositional activity) showed both the oils had significant activity against both tested insects. Citrus reticulata had shown better activity than Citrus sinensis against Callosobruchus chinensis and Tribolium castaneum. Both the essential oils exhibited good to moderate antioxidant activity in dose dependent manner. Chelating activity of both the oils was found to be almost similar while, free radical scavenging activity was found to be more in case of Citrus reticulata. Reducing power was greater in case of Citrus reticulata than Citrus sinensis. Both the essential oils were found to be active against Fusarium oxysporum and Rhizoctonia solani and no activity of both oils were observed against Pseudomonas aureginosa at tested concentrations. Based on the above results it can be concluded that, besides its academic importance Citrus sinensis and Citrus reticulata can be good source of natural antioxidant, natural antifungal and natural insecticidal and they can be exploited in future after more clinical and pilot scale trials.
Open Access
Equilibrium modeling and kinetic studies on the biosorption of Chromium (III) from synthetic waste water using Cupressus torulosa and Taxus baccata”
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Verma, Anil; Viveka Nand
In recent times, Heavy metals in general and chromium in particular has received a great deal of attention because of their toxicity. Studies were undertaken to examine the biosorptive ability of Gymnosperm plant species, Cupressus torulosa, and baccata, , collected from high altitude of Uttrakhand hills, to remove the Chromium (III) metal ions from aqueous solution. Batch mode experiments were conducted at cold and hot temperatures (25˚±5˚C and 40˚±5˚C) to study the effects of initial Cr (III) metal ion concentrations, pH, time and amount of biomass. Thus a removal of chromium is essential from the environment by cheap and ecofriendly process. The maximum percentage removal (%removal) and biosorption capacity (Qe value) were recorded at equilibrium conditions. The maximum removal of Cr (III), at cold and hot temperature condition by by C. torulosa and T. baccata, leaves were 97.83 and 93.66, 97.83 and 93.66 while by barks were 90.53 and 93.66% , 90.33 and 93.23% respectively. Langmuir, Freundlich and Temkin adsorption isotherm models were used to explain adsorption phenomenon of Cr (III) removal. Equilibrium data agreed well for biosorption of Cr (III). The kinetic data have been analyzed using Pseudo first order, Pseudo-second order and Elovich kinetic models. The experimental data fitted very well the Pseudo second order and Elovich kinetic models. The FT-IR spectra of dried unloaded and Cr-loaded plants biomass were obtained to understand the nature of possible interactions between the chromium metal ions and the functional groups of biosorbents. The FT-IR analysis revealed that the main functional groups involved in biosorption were carboxyl, carbonyl, amino, alcoholic and phenol. Significant morphological changes were observed using SEM analysis, which support the binding of metal with leaves and bark surfaces. Thus, it can be concluded that gymnosperms can be utilized as cost-effective and environment friendly alternative over commercial methods of treatment for removal of toxic metals and contaminants of water because these plants consists high metal binding properties at different environmental conditions.
Open Access
Chemical analysis, biological activity determination and DNA profiling of different accessions of Curcuma longa L. collected from Uttarakhand
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2014-08) Arya, Neelam; Om Prakash
Polyphenolics, known as nutritional secondary metabolities, plays an important role to protect the tissues by reducing the oxidative stress and enhance the nutritional value of food material. The total curcumin content, essential elements, phytochemical screening and antioxidant activity of 50 samples of Curcuma longa L. rhizome from various niches of Uttrakhand (Kumaun and Gharwal region) were analyzed. The highest curcumin content was found in the sample collected form Pithoragarh (37.93±0.12mg/g) and lowest content was in Patwadanger (9.29±0.51mg/g) collection. The Fe, Cu, Zn and Mn contents was found in the range of 20.89 to 3462.58, 1.11 to 198.03, 3.54 to 211.75 and 5.56 to 1108.80 mg/kg respectively. These contents were maximum in sample collected from Dholia pata (Bageshwar), Nanakmatta (Udhamsingh Nagar), Pantnagar (Udhamsingh Nagar) and Champawat and minimum in the sample collected from Kathgodam (Nainital), Harsil (Uttarkashi, Garhwal), Bhimtal (Nainital) and Dharchula (Pithoragarh). The P, Ca, Mg, K and N content was found in the range of 0.04 to 0.99, 0.19 to 1.42, 0.09 to 0.85, 0.57 to 2.99 and 9.52 to 35.28% respectively. The P and Ca contents were maximum in the sample collected from Devprayag (Chamoli), Khatima (Udhamsingh nagar), Mg and K in Chamoli and N in Roorkee (Haridwar). This content was found minimum in sample collected from Barswar (Pauri Garhwal), Pithoragarh, Ramnagar (Udhamsingh Nagar) Kanda (Bageshwar) and Dwarahat (Almora). The amount of total phenols varied from 6.71±1.29 to 51.49±1.41mg/g. The maximum phenolic content was found in Pithoragarh collection and minimum in Khatima (Udhamsingh nagar) collection. The total flavonoid contents varied from 6.34±1.81 to 28.96±2.47 mg/g with maximum flavonoid in the sample collected from Kapkot (Bageshwar) and minimum in Kanda (Bageshwar) collection. Orthodihydroxy phenol (ODP) varied from 0.69±0.10 to 8.11±0.11 mg catechol equivalent/g. The maximum ODP was found in the sample collected from Chamoli and minimum in Chakrata (Dehradun). The content of ascorbic acid varied from 0.122 ± 0.008 to 2.61 ± 0.0071mg/g. The total sugar, reducing and non-reducing content in all the fifty collections varied from 56.25±0.77 -- 13.75±0.72, 11.2±0.39 -- 1.2±0.10 and 49.67±0.84 -- 8.58±1.24 mg/g respectively. The Munsiyari (Pithoraghar) collection showed maximum amount of total sugar and non-reducing sugar while Nanakmatta (Udhamsingh Nagar), Deharadun and Pantnagar (Udhamsingh Nagar) showed the minimum amount. The total Protein content in different samples ranged from 4.87±0.08 to 24.52±0.11 mg/g with maximum in Roorkee (Haridwar) collection and minimum in Chakrata (Dehradun) collection. The other samples showed the amounts in between of maximum and minimum and all the samples exhibited in vitro – antioxidant activity in a dose dependent manner. The total antioxidant capacity and FRAP was found in the range of 27.44±2.5 to 94.78±3.4 mg/g and 6.99±.39 to 54.84±.53 μmole FeSO4 equvalient/g respectivily. The methanolic extracts also showed DPPH radical scavenging activity, Hydroxy radical scavenging activity, superoxide radical scavenging activity and nitric oxide radical scavenging activity in dose dependent manner but significantly less compared to the standards (EDTA, ascorbic acid and qurecitin). The IC50 values of these activities were varied from 55.93±0.25 to 275.41±0.53, 39.57±.42 to 77.68±.63, 43.76±0.53 to77.12±0.59 and 39.02±0.46 to 76.15±0.39μg/ml respectively. Out of fifty samples two samples selected from Ukhimath and Haldwani, showed good anti-inflammatory, antinociceptive and antipyretic activities in dose dependent manner. None of the extract exhibited toxicity at 400, 600 and 800 mg/kg concentration. The RAPD technique was performed to detect genetic diversity in the twenty turmeric sample. Ten RAPD primers yielded 84 alleles, averaging 8.4 alleles per locus varying from seven to ten. Polymorphism index contents values ranging from 0.24 to 0.77 with the mean of 0.43. The observed heterozygosity (Ho) and gene diversity (Nei’s) for individual loci varied from 0.158 to 0.672 and 0.154 to 0.564, respectively. The Shannon’s informative index (I) of loci varied from 0.137 to 0.846 with the mean of 0.425 per locus. Fixation index (Fis), was also calculated, which ranged from 0.125 to 0.600 with an average of 0.377. A genetic relationship among accessions were analyzed by cluster analysis using unweighted pair group method with arithmetic mean (UPGMA), the average-linkage method with the similarity matrix as input data and classified all twenty turmeric accessions into two major groups comprising six clusters. From result, the samples collected from Lohaghat and Patanpatni have the same parents and sample collected from Harsil and Munsiyari and from kanda and Champawat are closely related accessions. The wide geographical and climatic distribution is indicative of the fact that there exists a tremendous genetic diversity in Curcuma longa which needs to be identified and catalogued for scientific and breeding programmes for their commercial usages.
Open Access
Synthesis of bioactive molecules using novel methods and evaluation of their biological activities
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2010-08) Pandey, Jyoti; Virendra Kumar
Five series of compounds namely cinnamic acid amides, ß-benzoylacrylic acid esters, 1, 5 benzodiazepines, benzimidazoles and .-acetamido keto esters were synthesized. Analogues of naturally occurring cinnamic acid amides and ß-benzoylacrylic acid esters were synthesized in order to evaluate their herbicidal potential against Echinochola colona (weed of rice) and Phalaris minor (weed of wheat) respectively. Some of the analogues of cinnamic acid amides and ß-benzoacrylic acid esters exhibited activity at par with the standards. Benzodiazepines, benzimidazoles and .-acetamido keto esters were undertaken in order to develop new techniques and catalysts. A new catalyst trichloro acetic acid was developed for the synthesis of benzodiazepines by the reaction of o-phenylenediamine and substituted aldehydes. Some of the synthesized benzodiazepines were found to antibacterial and duodenal smooth muscle relaxation activity. For the synthesis of benzimidazoles two new catalyst ferric chloride and silica supported calcium chloride dihydrate have been developed as novel and efficient catalysts. For the synthesis of .-acetamido keto esters two new catalyst oxalic acid and calcium chloride dihydrate have been developed.
Open Access
Supercritical carbon dioxide assisted synthesis and studies on multiwalled carbon nanotube polymer composites
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2010-07) Thakur, Aparna; Zaidi, M.G.H.
The supercritical fluids have been used as inexpensive and environmentally benign media for the synthesis and processing of a variety of materials of technological significance. In the present work efforts have been made to synthesize a series of MWCNT/polymer composites through in-situ polymerization of selected monomers in scCO2. All the samples were synthesized at 1200 psi and 90±1oC in scCO2. PPy, PTh, their copolymers and nanocomposites have been synthesized through chemical oxidative polymerization of respective monomers in presence of ferric chloride. PGMA and corresponding nanocomposite have been synthesized through free radical polymerization in presence of AIBN. All the polymerization reactions have been monitored through variations in weight average molecular mass, polydispersity index and rheoviscosity. The formation of nanocomposites has been ascertained through Uv-vis, FT-IR and NMR spectra. Their microstructure has been investigated through XRD spectra, TEM and AFM. Thermal and electrical properties of samples have been studied through simultaneous TG-DTG-DTA and four probe methods.
Open Access
Effect of some soil amendments on dissipation and leaching of pesticides used in rice and wheat crops
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-07) Joshi, Varsha; Srivastava, Anjana
The effect of different soil amendments on leaching and dissipation of the insecticides fipronil and chlorpyrifos, and the herbicide sulfosulfuron was studied under laboratory as well as field conditions in rice and wheat crop. The extraction of pesticides was done using simplified QuEChERS method. Fipronil and Sulfosulfuron were extracted in acetonitrile and were analysed in HPLC with a retention time of 5.9 and 5.1 minutes respectively, whereas hexane was used for the extraction of Chlorpyrifos which was analysed in GC at a retention time of 5.2 minutes. The recovery of fipronil, sulfosulfuron and chlorpyrifos from soil, water and crop samples was 83.0 to 94.6 %, 83.7 to 93.8% and 83.5 to 95.3% respectively. Results from the soil column leaching experiment concluded that CS and FCD were effective in reducing leaching of all the pesticides under laboratory conditions. Gypsum, CS and FCD resulted in the fast dissipation of fipronil and sulfosulfuron, whereas the half life of chlorpyrifos was reduced by the application of FCD and FYM over control. All the parameters of the GW were within the permissible limit in rice and wheat crop. CS and FCD were very effective in reducing the pesticide residue in soil, ground water and crop produce in both the crops. The residue of fipronil in rice grains was below the limit of detection (<0.002), whereas a considerable amount of fipronil was detected in rice straw. The concentration of chlorpyrifos detected in rice grains and straw was below the set MRL value. The residue of sulfosulfuron detected in wheat straw was below the maximum residue limit (0.1 mg/kg) and was not detected in wheat grains.
Open Access
Phytochemical analysis of some plants of family Lamiaceae and Amaranthaceae and screening of their biological activities
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2011-01) Agarwal, Ruchi; Pant, A.K.
The essential oils of different collections of T. quadrifarium Buch.-Ham. ex D.Don from Patwadangar and Bhowali (Kumaon region) were analysed by GC and GC/MS. Analysis of T. quadrifarium essential oil from Patwadangar showed that presence of the 49 components contributing to 91.22% of the oil. The major components were E-7- caryophyllene (25.0%), copaene-4-8-ol (10.0%), caryophyllene oxide (9.5%), aromadendrene (6.3%), 8-humulene (4.2%) and germacrene-D (3.3%). The essential oil of T. quadrifarium for Bhowali showed the presence of 63 components contributing to 97.7% of the total oil. The major constituents in the oil were caryophyllene oxide (32.1%), 8-cadinol (7.2%), humulene epoxide (5.3%), 8-epi muurolol (5.3%), cadalene (5.3%), 7-selinene (5.2%), germacrene-D (4.6%) and t-cadinol (3.8%). Comparison of the results revealed that the composition of essential oil of T. quadrifarium from Bhowali collection seem to be quite different from the other collection of Patwadangar. GC-MS analysis of TMS derivative of methanol extract of T.quadrifarium revealed the presence of more than fifty components which contributed to 91.67% of the total TMS derivative. The major phenolic acids identified in the extract were salicylic acid (0.2%), syringic acid (0.1%), p-coumaric acid (0.01%) and caffeic acid (0.2%). The only phenolic acid glycoside identified in the extract was caffeoyl glycoside (0.1%). The GC and GC-MS analysis of the essential oil of Scutellaria scandens Buch.-Ham. ex D.Don revealed that the presence of the 43 components contributing to 71.4% identified component of the oil. 5-neo-cedranol (7.0%), caryophyllene oxide (6.8%), cuprene (6.7%), vaterianol (5.2%), curcuphenol (4.1%), 7-cedrene (3.5%), 3-iso-thujpsanone (2.7%), benzalacetone (2.3%), 3-thujopsanone (2.2%) and <–muurolol (2.2%) were the major components. The GC and GC-MS analysis of the essential oil of Scutellaria repens Buch.-Ham. ex D.Don showed the presence of 57 compounds, accounting for 80.95% identified component of the oil. The major components were cis-thujopsene (28.1%), 7-cedrene (5.7%), germacrene-B (4.6%), epi-8-cedranol (4.2%), >-cadinene (2.1%), 8-acoradiene (2.0%) and 7-chamigrene (1.9%). The essential oil of the Pogostemon benghalensis Kuntze resulted in the identification of 42 constitutents contributing to 73.57% identified component of the oil. The major constituents in the oil were furan eudesma-4,10 diene (32.8%), arbusbulone (10.21%), 8-yalangene (7.12%), 7-caryophyllene (7.02%), germacreone (6.23%), 1-octene-3-ol (5.02%), 7-bisabolene (4.20%), Eocimene (2.43%), elemol (2.58%), ?-bisabol-1,4-diene (1.38%), germacrene-D-4-ol (1.40%), 7-copane-48-ol (1.24%), 8-cadinol (1.51%), 7-eudesmol (1.70%), germacrene-B (2.84%), germacrene-D (1.34%) and 7-elemene (1.07%). The two components of the essential oil of Pogostemon benghalensis were separated by column chromatography. The compounds were identified on the basis of their spectroscopic data as fruan eudesma-4,10 diene and 8-cadinol. The phenolic acid and their glycosides identified in the TMS derivative of methanol extract of Pogostemon benghalensis were ferulic acid (0.04%), caffeic acid (0.1%), p-coumaric acid (0.1%), chlorogenic acid (0.5%) and caffeic acid glucoside (0.1%). Two compounds were isolated from the benzene extract of Cyathula tomentosa Moq. root (Compound I and II). 1HNMR, 13CNMR and DEPT spectra were recorded, the isolated compound I was identified as 7-sitosterol while compound II remained unidentified. The in vitro antioxidant potential of essential oils and extracts were evaluated for reducing power essay, 2’,2’-diphenylpicryl hydrazyl (DPPH) radical scavenging activity and chelating activity of Fe2+ ion. The maximum reducing power observed for essential oil of S. repens (1.220±0.00 to 1.280±0.000), followed by S. scandens (0.913±0.000 to 1.210±0.000), P. benghalensis leaf (0.753±0.000 to 1.137±0.001), P. benghalensis root (0.638±0.000 to 1.280 ±0.002) and T. quadrifarium (0.324±0.000 to 0.370±0.000) at dosage from 5 μL to 25. All the oils possess lower reducing power than standard BHT (2.302±0.000 to 2.508±0.001), catechin (4.000±0.000 to 4.000±0.000) and gallic acid (4.000±0.000 to 4.000±0.000). In methanolic extract maximum reducing power was observed for T. quadrifarium and S.scandens extract (4.000±0.000 and 4.000±0.000) respectively. The minimum reducing power was observed in extract of P. benghalensis root (0.461±0.001 to 0.612±0.000), followed by S. repens (0.367±0.00 to 0.461±0.008). The methanolic extract of flower of C. tomentosa (0.600±0.001 to 0.646±0.003) showed maximum reducing power followed by C.tomentosa leaf (0.334±0.000 to 0.483 ±0.001) and C. tomentosa root (0.200±0.000 to 0.436±0.001). All the methanolic extracts of C. tomentosa exhibited less reducing power than standards at concentration 5 mg to 25 mg. The essential oil of P. benghalensis (root) and P. benghalensis (leaf) (92.13±0.034 to 97.37±0.000 and 81.54±0.164 to 82.92±0.000) exhibited maximum DPPH radical scavenging activity. Minimum scavenging activity observed in essential oil of T. quadrifarium (43.03±0.001 to 44.29±0.000). Methanolic extract of T. quadrifarium (81.12±0.282 to 92.10 ±0.236) exhibited maximum scavenging activity and P. benghalensis (72.28±0.040 to 80.87±0.034) showed the least scavenging activity. Methanolic extract of C. tomentosa leaf (63.43±0.040 to 78.22±0.346) exhibited maximum scavenging activity followed by C. tomentosa root (56.51±0.034 to 72.33±0.800) and C.tomentosa flower (58.79±0.040 to 70.76±0.040). Essential oil of S. scandens (69.56±.001 to 78.92±.001%) showed highest chelating activity followed by T. quadrifarium, S. repens and P.benghalensis root (69.91±0.000 to 72.88 ±0.000%); (66.14±0.000 to 76.51±0.001%) and (64.87±0.040 to -70.17±0.073%). The methanolic extract of S. repens (75.67±0.150 to 87.28±0.005 %) showed maximum chelating activity followed by P. benghalensis root (73.71±0.045 to 77.63±0.005). The methanolic extract of C. tomentosa flower (83.10±0.057 to 98.24±0.098) and C. tomentosa root (87.39±0.000 to 91.24±0.040) showed more chelation in comparison to EDTA and citric acid (86.50±0.017 to 89.19±0.040 and 86.19 ±0.017 to 92.54±0.040) respectively. Biochemical assay for the different plants of family Lamiaceae revealed that all the plants were possess the total phenol more than 1mg/100, ortho dihydric phenol content also more than 1mg/100 in T. quadrifarium, P. benghalensis and S.repenes. The flavonoid contents were observed less than 1mg/100 in all species except T.quadrifarium. All the tested oils of T. quadrifarium and P. benghalensis root and extracts P.benghalensis and C. tomentosa showed anti-inflamatory, anti-nociceptive and antipyretic activities in dose dependent manner. All the oils and extracts showed reduction in inflammation but less than standard drug ibuprofen. T. quadrifarium extract showed maximum anti-nociceptive avtivity at the dose of 100 mg/kg body wt followed by C.tomentosa. The oils and extracts of P. benghalensis, T. quadrifarium and C. tomentosa produced significant (p<0.05) antipyretic effect in a dose dependent manner. None of the oils and extracts exhibited toxicity at 40, 60 and 80% and 400, 600 and 800 mg/kg concentration. Ibuprofen, indomthacin and paracetamol were taken as standard drugs for comparison.
Open Access
Persistence/issipation, adsorption-desorption and leaching behaviour of ethofumesate and oryzalin herbicides in soil and water
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2012-08) Pal, Suman Lata; Sand, N.K.
Herbicides are indispensable for sustained agricultural production, but due to their hazardous after effects on human beings, wild life and environment, it is mandatory to evaluate their residues. The investigation was undertaken to develop simple method for extraction and analysis of persistence, adsorption-desorption and leaching studies of two herbicides ethofumesate and oryzalin in soil, water. Ethofumesate [(±)2-ethoxy-2,3-dihydro-3,3-dimethyl-5-benzofuranyl methane-sulfonate] member of Benzofuron used as pre - and/or post-emergence in sugar beet and other beet crops, turf, graminaceous plants, broad leaf plants, weeds of sugar beet meadow, greensward meadow and other meadows such as rye grass and the other pasture grasses. Oryzalin [3,5-dinitro-N4,N4-dipropylsulfanilamide] belongs to Dinitroaniline herbicide family has broad spectrum of activity against annual grasses, broadleaf weeds, woody shrubs and wines in grapes, berries and orchard crops, including both fruits and nuts. In the present study, tap water and soils (silt clay loam and sandy loam) samples randomly drawn at different soil depth were characterized for general physicochemical properties. UV-Vis spectroscopy revealed λmax of herbicides as 280 nm which was used for the detection in HPLC. The limit of detection of ethofumesate and oryzalin in soil and water were 0.02 μg g-1 or ml and 0.01 μg g-1 or ml respectively. During experiment, extraction of herbicide from soil was done with acetone: methanol (5:1 v/v), 5% sodium chloride, n-hexane and dichloromethane. In case of water, partitioning was performed with dichloromethane. The HPLC conditions during analysis was ODS-2 (C-18 column), mobile phase with composition methanol: water (70:30 v/v) and flow rate of mobile phase was 1ml min-1. Ethofumesate and oryzalin often both have a “biphasic” breakdown pattern in soil follow first order kinetics. The half life (t1/2) values for ethofumesate were found for initial and later both phases were 12.70 & 51.88 days and 15.12 & 55.72 days at recommended and double recommended dose in sandy loam soil whereas, in silty clay loam soil 9.49 & 64.02 days at recommended dose and 11.53 & 68.39 days at double recommended dose. On the other hand the half-lives of oryzalin for both phases were 6.50 & 39.08 days and 6.60 & 42.38 days at recommended and double recommended dose in sandy loam soil whereas, in silty clay loam soil were 5.56 & 51.00 days at recommended dose and 6.006 & 56.78 days at double recommended dose respectively. No detectable residue (< 0.02 μg g-1 for ethofumesate and 0.01 μg g-1 for oryzalin) of oryzalin and ethofumesate were found on 150th and 170th day of application in silty clay soil, 120th and 150th day of application in silty clay soil and 120th and 90th day of application in water respectively at both doses. While, the degradation pattern of both herbicides followed monophasic first order kinetics in water. In water the half-lives of ethofumesate were found to be 34.59 and 37.15 days whereas, for oryzalin 42.99 and 48.53 days at both doses recommended and double recommended dose respectively. Adsorption was highest in case of higher concentration on both soils and adsorption increases as concentration increases. The percent adsorption was higher in silty clay loam soil than sandy loam soil due to presence of higher organic content in silty clay loam soil. The adsorption of oryzalin was higher than ethofumesate in both soils. In the presence of organic matter the adsorption increased as concentration increases. So, organic matter may be used to decrease the mobility of ethofumesate and oryzalin in soil. The ethofumesate and oryzalin herbicide’s adsorption-desorption data described well to Langmuir, Freundlich and Temkin isotherms, respectively. However, the fit to Freundlich adsorption model was greater than that of Langmuir or Temkin on the basis of values of regression coefficient. Leaching study of ethofumesate and oryzalin were performed in silty clay loam soil and sandy loam soil at recommended dose. The residues of herbicides were found to be beyond 0-20 cm and 0-10 cm of soil depth, and showing less mobility in both types of soil. But in presence of organic amendments such as vermicompost and FYM (Farm Yard Manure) greatly enhanced the adsorption capacity of herbicides in soil depths in soil columns.

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