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2014 - 20184
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Author: Jaskiran Kaur × Start date: 1989 × Type: Thesis ×
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    ThesisItemOpen Access
    Characterization of psychrotolerant rhizobacteria for Zn biofortification in lentil (Lens culinaris L. Medikus)
    (Punjab Agricultural University, Ludhiana, 2018) Jaskiran Kaur; Khanna, Veena
    Seventy psychrotolerant rhizobacterial isolates were evaluated for their PGP traits at 10°, 20° and 30°C. Highest IAA production was recorded with isolates PRh-9, PRh-14, PRh- 15, PRh-60, PRh-61 and that was confirmed by HPLC (8.98, 4.91, 5.66, 2.73 and 1.62 μg/ml respectively). Isolate PRh-14 recorded maximum Zn-solubilization potential of 354, 304.8 and 284.5 ppm at 10°, 20° and 30°C. It also recorded the maximum P-solubilization efficiency, gibberellins, EPS production and biofilm formation at 10°, 20° and 30°C. Eleven isolates amplified acdS gene which confirmed the presence of ACCD activity. Maximum naringin and quercetin production was shown by isolate PRh-61 and PRh-9, further confirmed by TLC studies. Highest antagonistic activity was recorded by PRh-9 against Rhizoctonia bataticola and Fusarium oxysporum (33.3% and 48.1% respectively) and was also established by SEM analysis. Potent siderophore, salicyclic acid and HCN producers were PRh-9, PRh- 61 and PRh-60. The SEM analysis of root surface revealed that coinoculation with Rhiobium and PRh-14 helped in maintaining the root integrity owing to biofilm formation on the root surface. Under field conditions coinoculation of Rhizobium with PRh-15, PRh-14, PRh-9, PRh-61, PRh-60 and PRh-30 further increased by grain yield by 1.7, 4.4, 3.7, 2.5, 2.09, 1.5% respectively, over Rhizobium alone. A significant increase in the grain and straw zinc content was recorded with the treatment R+PRh-14 (105.9 and 141.0 ppm respectively). The DGGE analysis of soil DNA depicted a composite banding pattern that reflected a high microbial diversity. The promising rhizobacterial isolates were identified as PRh-9 (Pseudomonas flourescens), PRh-14 (Aeromonas hydrophila), PRh-60 (Lysinibacillus fusiformis) and PRh-61 (Pseudomonas korensis) based on 16S rDNA sequencing.
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    ThesisItemOpen Access
    Chromium adsorption studies on synthesized magnetite activated carbon nanocomposites
    (Punjab Agricultural University, Ludhiana, 2017) Jaskiran Kaur; Manpreet Kaur
    Adsorptive properties of synthesized magnetite activated carbon nanocomposites are investigated for the facile removal of Cr (VI) ions from water. Fe3O4 NPs and its nanocomposites with activated carbon were characterized by X-ray diffractiion pattern (XRD), FT-IR spectroscopy, Vibrating sample magnetometer (VSM), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM) and Brunauer Emmet Teller (BET) surface area analysis as analytical tools. TEM images revealed the agglomerated spherical morphology of Fe3O4NPs and nanocomposites. A comparative analysis of the Fe3O4 NPs, nanocomposites and activated carbon for the removal of Cr (VI) ions from water was carried out by batch method and Cr (VI) content was estimated spectrophotometrically. The effect of operating parameters including adsorbent dose, temperature, contact time, pH and initial metal ion concentration of Cr (VI) were studied. Optimum pH for adsorption was 2. Values of ∆Go, ∆H˚ and ∆S˚ were found to be negative for all adsorbents, indicating exothermic and spontaneous nature of adsorption process The trend for the Cr (VI) ions percentage removal in the ascending order was Fe3O4 NPs
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    ThesisItemOpen Access
    Chemistry and biological activity of lignin from pea (Pisum sativum L.) peel
    (Punjab Agricultural University, Ludhiana, 2017) Jaskiran Kaur; Uppal, S.K.
    Pea peel, an abundant agricultural waste was evaluated to determine its chemical composition by detergent system method and was found to contain 18.60% hemicellulose, 26.00% cellulose and 5.33% lignin. Pea peel also contained considerable amount of minerals as detected by ICAP-AES. Different extracts of pea peel were prepared by four extraction methods (maceration, orbital shaking, ultrasonic assisted extraction and soxhlet extraction method) by different solvents (petroleum ether, isopropyl alcohol, chloroform, ethyl acetate and methanol). Soxhlet extraction method was found to be the best method giving maximum total phenolic content of 11.14 mg gallic acid equivalent g-1 dry weight in methanol extract. Lignin was isolated from pea peel by acid and alkali treatment (5, 7.5 and 10% NaOH) and best yield was given by 10% NaOH treatment with 82.5% recovery of lignin. Treated and untreated pea peel samples were analyzed by SEM to study external morphology and treated samples were again analyzed to determine their chemical composition. Isolated Lignin and its chemically modified forms i.e. glyoxalated, esterified, aminated and sulfonated lignins were characterized by FT-IR, 1H NMR, 13C NMR spectral techniques and elemental analysis. Pea peel extracts, isolated lignin and modified lignins were evaluated for their antioxidant activity, antibacterial activity by disc plate method against Burkholderia sp., Pseudomonas aeruginosa and Klebsiella sp. and antifungal activity by poisoned food technique against Fusarium oxysporum using 3,5-di-tert-butyl-4-hydroxytoluene (BHT), tetracycline and bavistin as standards, respectively. Methanol extract was found to exhibit highest antioxidant, antibacterial and antifungal activities whereas lignin and its modified forms showed different potential in all activities.
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    ThesisItemRestricted
    Efficacy of low temperature tolerant plant growth promoting rhizobacteria on symbiotic efficiency, growth and yield of lentil (Lens culinaris L. Medikus)
    (Punjab Agricultural University Ludhiana, 2014) Jaskiran Kaur; Khanna, Veena
    A total of 35 isolates of rhizobacteria were isolated at 10 and 15°C from 20 soil samples taken from different locations and were characterized as belonging to genera Bacillus (23), Pseudomonas (11) and Serratia (1). IAA production ranged from 3.2-19.3 μg/ml and 7.6-20.4 μg/ml in the presence of tryptophan at 10 and 15°C respectively. Isolates J-6 was found to be strong producer of HCN at 10°C, however, at 15°C J-17 was the highest producer. Maximum P-solubilization index was shown by isolate J-14 (5.5 cm) followed by J-17 (5.4 cm) and J-18 (5.3 cm). At 15°C was shown by isolate J-5 (87.4 mg/100ml) showed highest P-solubilization followed by J-17 (77.2 mg/100ml). However, none of the isolates could solubilize phosphorus at 10°C. At 15°C maximum siderophore production was observed with isolate J-18 as evident by the halo on CAS agar and highest catechol type siderophore was produced by J-17 (606.1 µg/ml) followed by J-18 (595.1 µg/ml). However as in case of P-solubilization no siderophore production was observed at 10°C. Field experiment was conducted to examine the effect of co-inoculation of Rhizobium with PGPR strains (J-3, J-17, J-18 and J-30) for growth, symbiotic parameters and yield in lentil variety (LL-931). Coinoculation showed a significant increase in nodule number, nodule dry weight, plant and root dry weight, chlorophyll and leghaemoglobin content over Rhizobium alone. Application of PGPRs J-3, J-17, J-18 and J-30 along with Rhizobium further enhanced the grain yield (1.8, 4.4, 3.1 and 1.4%) over Rhizobium inoculation alone.