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ThesisItem Open Access Green synthesis of silver nanoparticles using leaf and seed extracts of Fenugreek (Trigonella foenum-graecum L.) for catalytic, antioxidant and antimicrobial activities(CCSHAU, Hisar, 2022-12) Moond, Monika; Sushila SinghThe present study was undertaken for the synthesis of Fenugreek (Trigonella foenum-graecum L.) seeds and leaves extract mediated silver nanoparticles and evaluation of their antioxidant, antimicrobial and catalytic activities. Proximate composition and chemical parameters viz. moisture, ash, crude fat, crude fiber, crude protein, total carbohydrates, minerals (Fe, Cu, Zn, Mn), tannins and alkaloids were analyzed in seeds and leaves of Fenugreek. Phytochemical parameters viz. total phenolic content, total flavonoids, total sugars, reducing sugars and non-reducing sugars in seeds and leaves were extracted with three solvents namely aqueous, methanol and acetone. The aqueous extract of Fenugreek seeds and leaves contained adequate amount of phytochemicals which act as reducing, stabilizing and capping agent for Silver nanoparticles (AgNPs). Several physico-chemical parameters such as effect of extract amount, effect of AgNO3 concentration, effect of temperature, effect of pH, effect of reaction time were optimized for the efficent synthesis of silver naoparticles. Optimized conditions for biosynthesis were found as; reaction mixture containing seed extract (2mL) or leaves extract (0.2 mL) in 25 mL of 1mM AgNO3 solution at 45ºC temperature and neutral pH. Reaction mixture was incubated for 48 hrs for FS-AgNPs and 24 hours for FL-AgNPs in dark condition to ensure the compete reduction of Ag+ ions. Characterization of Biosynthesized nanoparticles was done using several techniques such as UV-Vis spectroscopy, Particle size analyzer (PSA), FESEM, EDX, HRTEM, SAED, FTIR and XRD to examine the size, shape and morphology of silver nanoparticles. Size of synthesized AgNPs were in the range of 10-60 nm, most of them were spherical shape, monodisperse and crystalline in nature having FCC lattice. Antioxidant activity (DPPH free radical scavenging activity), antimicrobial activity using agar well diffusion method against Staphylococcus auerus, Xanthomonas spp., Macrophomina phaseolina and Fusarium oxysporum were compared with crude plant extract. Biosynthesized AgNPs showed enhanced bilogical activity. AgNPs were found to have appreciable catalytic activity for the degradation of p-nitrophenol with rate constant 0.1075 min-1 and 0.1398 min-1 for FS-AgNPs and FL-AgNPs, respectively.ThesisItem Open Access Persistence, mitigation and leaching of atrazine and its metabolites in soil(CCSHAU, Hisar, 2023-01) Priyanka; Duhan, AnilPersistence, mitigation and leaching potential of atrazine and its metabolites in sandy and clay loam soils was studied. Soil samples were collected periodically for dissipation and mitigation studies. Leaching experiment was performed at 50 μg (single dose) and 100 μg (double dose) in both soils taken in plexi glass columns. Enzymatic activities were studied as per the explained method in available literature. Sample preparation techniques i.e. Matrix solid phase dispersion (MSPD), was optimized using different solvents for both soils at fortification level of 0.001 μg/g for sample preparation. The limits of detection and quantification were ranged 0.0005-0.001 and 0.001-0.005μg/g, respectively for AT and metabolites. In clay loam and sandy loam soil, average recoveries of atrazine and metabolites ranged from 81.3-83.1% and 84.2-86.3%, respectively in methanol. Dissipation followed first-order kinetics. The residues reached below detectable limit after 30 and 60 days in sandy loam and clay loam soils, respectively. Presence of organic manures stimulated while BGC inhibited the dissipation of atrazine in both soils. Urease activity decreased up to 30 days and boosted thereafter up to 60 days in all treatments of clay loam soil. AT exhibited deleterious effect on urease activity up to 30 DAT followed by DEA and DIA in clay loam soil. AT and DEA stimulated while DIA inhibited DHG activity on 0 DAT in comparison to control. The residues of atrazine and its metabolites found in leachate fractions suggested about its highly mobile nature, and possible threat of surface and ground water contamination. The presence of a notable collection of residues in leachate fractions suggests the potential for surface and groundwater contamination. DEA and DIA metabolites, in particular, caused springtail Folsomia candida and earthworm Eisenia fetida to have longer and more unacceptable risks. If residues similar to those found in leachate fractions reach water bodies, they may be toxic to a variety of freshwater fish, aquatic arthropods, amphibians, and aquatic invertebrates. Future research should take a more comprehensive approach to assessing ecological health and potential threats to non-target species.ThesisItem Open Access Persistance and decontamination studies of a combination formulation (pyriproxyfen 5% EC + fenpropathrin 15% EC) in okra and soil(CCSHAU, Hisar, 2023-02) Pooja; SushilThis study developed and validated a methodology for extracting the residues utilizing the QuChERS method, as well as the conformation and quantification of Pyriproxyfen and Fenpropathrin residues using GC-MS/MS working at low LOQ (0.01 mg kg-1). The field application of recommended (37.5 + 112.5 g a.i. ha-1) and double recommended dose (70 + 225 g a.i. ha-1) leads to initial deposits of Pyriproxyfen (0.359, 0.584 mg/kg) and Fenpropathrin (0.643, 0.951 mg /kg) which dissipated by following first order kinetics with half-life value ranged in between 1.79-1.84 (Pyriproxyfen) and 2.27-2.31 days (Fenpropathrin) at T1-T2 doses, respectively. The estimated pre-harvest intervals (PHI) for Pyriproxyfen and Fenpropathrin were 6.03 and 11.51, 0.91 and 2.54 days at T1 and T2 doses, respectively. There were no residues of Pyriproxyfen and Fenpropathrin in the soil after 1 day of the application of sumiprempt formulation indicating its safety for the next crop. Even though all the decontamination processes were successful in reducing the levels of both chemicals left behind, washing + boiling proved to be the most efficient. Residues of Pyriproxyfen and Fenpropathrin persisted for a little longer period in soil under laboratory conditions. ZIF-8 was synthesized by hydrothermal, sonochemical, and microwave-assisted methods, and its structural, physical, and chemical characteristics were investigated using FTIR, XRD, SEM, BET, and zeta seizer. ZIF-8 achieved a 69%, and 65 % removal of Pyriproxyfen and Fenpropathrin (20 mg/L) under optimized conditions, respectively.ThesisItem Open Access Dissipation, decontamination and leaching behaviour of thiamethoxam + λ cyhalothrin (ready mix) in soil and chilli(Chaudhary Charan Singh Haryana Agricultural University hisar, 2022-09) Pooja; SushilThe study reports the persistence as well as the decontamination pattern of insecticides, λ -cyhalothrin and thiamethoxam in chilli fruits following spray application of their ready-pre mix. For extraction and clean-up, three two different methods namely liquid-liquid partitioning and QuEChERS with clean-up were used in association with GC-MS/MS. The LOD and LOQ of the method determined were 0.01 μg g−1 and 0.005 μg g−1, respectively, and all the recoveries were found above the range of 80 per cent. Thiamethoxam persistent up to day 15 in both the doses with half-lives of 3.45 and 3.90 days respectively. While λ -cyhalothrin persisted up to day 5th with half-lives of 1.49 and 1.52 days. Washing followed by frying was observed to be the best method of decontamination. It was followed by washing with 1 % vinegar solution, 2 % salt solution, 2% tamarind with least in case of washing with water. No presence of λ -cyhalothrin and thiamethoxam residues were reported in chilli fruits which were much below their respective maximum residue limits (MRLs). In leaching experiment around 90 per cent of the residues were recovered totally, with no residues in leachates.