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2010 - 20185
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Author: Harpreet Kaur × End date: 2019 × Start date: 2010 × Thesis Type: M.Sc ×
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    Pretreatment of paddy straw by Delftia sp. for enhancing biogas production
    (Punjab Agricultural University, Ludhiana, 2018) Harpreet Kaur; Phutela, Urmila Gupta
    The present study was aimed to study the growth profile and lignocellulolytic enzyme (laccase, endoglucanase, exoglucanase and -glucosidase) profile of Delftia sp. PP4_S3 (bacteria) which was used for pretreatment of paddy straw. The pretreated paddy straw was used for enhancing biogas production. The comparison of biogas production from bacterial (Delftia sp. PP4_S3) and fungal (Coriolus versicolor MTCC 138) pretreated paddy straw also carried out. Maximum growth of Delftia sp. PP4_S3 was obtained after 72 h with OD (600nm) value of 1.890±0.27 and cell count of 8.76×107±0.02 in paddy straw based nutrient broth. In solid state fermentation, maximum laccase, endoglucanase, exoglucanase and - glucosidase activities of 203 Ug-1, 35.7 Ug-1 , 14.2 Ug-1 and 11.3 Ug-1 respectively were obtained as compared to 11.2 Uml-1, 6.46 U/ml-1, 1.85 U/ml-1 and 2.13 U/ml in submerged conditions. The pretreatment of paddy straw with Delftia sp. PP4_S3 showed maximum reduction of 7.46% total solids, 5.67% volatile solids, 40.6%cellulose, 22.5% hemicellulose, 45.7% lignin and 17.7% silica in 5 days of pretreatment period. Highest biogas production i.e. 180 l/kg PS, 560 l/kg TS and 673.2 l/kg VS (66.1% enhanced over control) was found on 3rd day of treatment. Paddy straw pretreated with Coriolus versicolor MTCC 138 showed 44.7% increased biogas production with 153.4 l/kg PS, 561.9 l/kg TS and 689.9 l/kg VS. Pretreatment of paddy straw with Coriolus versicolor MTCC 138 showed maximum reduction of 3.71% total solids, 4.61% volatile solids, 38.6%cellulose, 14.8% hemicellulose, 42.6% lignin and 16.2% silica. Both Delftia sp. PP4_S3 and Coriolus versicolor MTCC 138 showed significant reduction in lignin and silica content which indicate that both are lignin and silica degrader. However less pretreatment period required by bacteria make it more suitable for biogas production.
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    ThesisItemOpen Access
    Chemistry and antimycotic potential of mentha based shellac coatings against penicillium digitatum of kinnow fruit
    (Punjab Agricultural University, Ludhiana, 2018) Harpreet Kaur; Tandon, Ritu
    The present study deals with chemistry and antimycotic potential of Mentha based shellac coatings against Penicillium digitatum of kinnow fruit. Essential oil (EO) of two species of Mentha viz. Mentha piperita and Mentha arvensis was extracted using Clevenger-type apparatus. Per cent yield of essential oil of M. arvensis (2.8%) was found higher than M. piperita (2.1%) Compositional analysis of M. piperita essential oil by GC-MS revealed presence of 51 compounds. M. piperita EO exhibited better antimycotic potential than M. arvensis EO against P. digitatum. Hence, Process of nanoemulsion (NE) development of M. piperita EO was optimized for parameters such as oil and surfactant ratio (v/v) with three sonication times (ST) with the help of probe ultrasonicator. Effect of surfactant concentration and sonication time on droplet diameter and electrical conductivity was studied. Nanoemulsion of 1:0.5 ratio of oil and surfactant with 20 min ST exhibited smallest droplet diameter as well as maximum stability at refrigerator temperature (4°C) than ambient temperature (25°C) over the storage period of 2 months. M. piperita based shellac nanoemulsions were prepared for the best.1:0.5 (v/v) oil and surfactant ratio. NE with 15 minute ST showed more effective inhibition (96.0%) against P. digitatum in comparison to other nanoemulsions as well as pure M. piperita EO (71.0%). Optical and SEM results showed morphological changes in treated fungus. Nanoshellac coating showed maximum inhibition at par with the standard Carbendazim.
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    ThesisItemOpen Access
    Effect of salicylic acid on antioxidant defense system on berseem (Trifolium alexandrinum L.) against cold stress
    (Punjab Agricultural University, Ludhiana, 2017) Harpreet Kaur; Goyal, Meenakshi
    The objective of this study was to evaluate the effectiveness of salicylic acid (SA) pretreatment on antioxidant system in berseem under cold stress. Berseem seeds were (var. BL42 and BL-10) primed with water (control) and different concentrations of SA (25, 50, 75, 100 and 125 µg/ml) for 4 hours. Soaked seeds were germinated on moist filter papers in petri plates at 25°C in two different sets. After germination of three days one set of petri plates was exposed to cold stress (5°C) for five days and other set was remained at 25°C. Physiological and biochemical parameters were observed in root and shoot samples after seven days of germination. Higher vigor index was obtained at 50 and 75 µg/ml of SA pretreatment. SA pretreatment enhanced root and shoot length, fresh weight uptill 100 µg/ml and then decreased at 125 µg/ml of SA. Pretreatment with 50 and 75 µg/ml of SA showed higher increase in antioxidant enzyme (CAT, APX, GR, GPX and SOD) activities. SA pretreatment of 50 to 100 µg/ml concentrations resulted in upregulation of non-enzymatic antioxidants under both normal and cold conditions. Biochemical metabolites such as total protein, proline and total phenol were differentially affected by different salicylic acid treatments under cold stress. SA alleviated the adverse effect of cold stress by decreasing lipid peroxidation and H2O2 content in berseem seedlings. So SA pretreatment ameliorated the cold stress in berseem by upregulating enzymatic antioxidants, non-enzymatic antioxidants and biochemical metabolites.
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    ThesisItemOpen Access
    Synthesis and antifungal potential of copper fluoro carbamodithioates
    (Punjab Agricultural University, Ludhiana, 2017) Harpreet Kaur; Anjali
    Novel fluorinated carbamodithioato Cu(II) complexes were synthesized by one pot two step reaction protocol by the reaction of anilines with carbon disulfide followed by the addition of copper chloride. The synthesized Cu(II) complexes were analysed by CHN analysis, titrometric methods and spectral techniques. Their physical characterization colour and melting point were noted. All the synthesized organic complexes were screened for their in vitro antifungal potential against various phytopathogenic fungi viz. Bipolaris sorokiniana, Puccinia hordei and Puccinia striiformis by spore germination technique, using Propiconazole as positive control for comparison of the results. The complex 1a (tetraaquaphenylcarbamodithioatocopper(II) chloride) had inflicted highest fungitoxic potential against all the test fungi.
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    ThesisItemRestricted
    GENETIC ANALYSIS OF YIELD AND QUALITY TRAITS IN FINE GRAINED AROMATIC RICE GENOTYPES (ORYZA SATIVA L.)
    (2010) Harpreet Kaur
    The study on the genetic analysis of yield and quality traits in fine grained aromatic rice genotypes (ORYZA SATIVA L.) was undertaken at Punjab Agricultural University, Ludhiana during Kharif 2008 and 2009. Gene action and combining ability for morphological, milling and cooking quality characters were studied in a set of diallel crosses involving six parents. The genetic analysis revealed that for most of the morphological traits (days to 50 percent flowering, plant height, spikelets per panicle, spikelet sterility, grain yield and harvest index), milling traits (1000 grain weight of brown rice, 1000 grain weight of milled rice, kernel length, kernel breadth, length: breadth ratio, total rice recovery and head rice recovery) and cooking quality traits (water uptake ratio) both additive and dominance gene effects were involved with the predominance of non additive gene action. Additive gene action was more pronounced for characters like plant height, spikelet sterility, kernel length, length: breadth ratio, hulling percentage and alkali spreading value. Over dominance was observed for majority of traits except plant height, spikelet sterility, kernel length, length: breadth ratio, hulling percentage and alkali spreading value. Combining ability analysis indicated the significance of both general combing ability and specific combining ability effects. Punjab Basmati 2 was good general combiner for yield and its component traits while Pusa 1121 was good general combiner for milling and cooking quality traits. Among the crosses, Basmati 386/ Punjab Basmati 2 and Basmati 386/ Pusa 1121 were desirable for yield related traits while Punjab Basmati 2/ Pusa Basmati 1, Basmati 386/ Super Basmati, Basmati 370/ Pusa 1121 and Super Basmati/ Pusa 1121 were desirable for milling and cooking quality characters. Correlation studies revealed a negative association between yield and quality traits except for alkali spreading value. Generally, milling and cooking quality traits did not show any correlation.