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ThesisItem Restricted Effects of rice straw incorporation on phosphorus and zinc availability in rice-wheat sequence(Punjab Agricultural University, Ludhiana, 2019) Mandeep Kaur; Saini, Sat PalThe present study was conducted to investigate the effects of rice straw (RS) incorporation on P and Zn availability in surface (0-15 cm) soil under rice-wheat cropping sequence. The treatments were N application (0, 90, 120 and 150 kg ha-1, main plot) and RS incorporation (0, 5, 7.5 and 10 t ha-1, sub plot).Inorganic-P was dominating fraction (92% of total-P), while organic-P constituted only 8%. Relative preponderance of inorganic P fractions followed an order: calcium bound P (Ca-P) > aluminium-P (Al-P) > iron-P (Fe-P) > reductant soluble-P (Red-P) > saloid-P. Nitrogen and RS incorporation significantly (p<0.05) increased the concentration of inorganic P fractions, with highest concentration in RS10 and N150 treatments. The sequential extraction procedure for Zn fractionation showed the dominance of residual fraction (Res-Zn), and their relative abundance in the surface soil followed an order: water soluble and exchangeable Zn (WS+EX-Zn) < specifically adsorbed Zn (SpAd-Zn) < manganese oxide bound Zn (MnOx-Zn) < organic matter bound Zn (OM-Zn) < amorphous iron bound Zn (AFeOx-Zn) < crystalline iron oxide Zn (CFeOx-Zn) < Res-Zn. These Zn fractions were significantly increased with graded levels of RS incorporation. Increase in P fractions showed a linear positive relationship with SOC and available-P in soil. Zinc fractions were positively and linearly correlated to SOC and DTPA-Zn concentration. Maximum wheat grain yield was observed with N120 and RS7.5 treatments. Highest P and Zn uptakes were observed under RS10 treatment. These results showed that N application and RS incorporation significantly increased the P and Zn concentration in soil under rice-wheat cropping system.ThesisItem Open Access Physiological and biochemical changes associated with moisture stress tolerance in maize (Zea mays L.) genotypes(Punjab Agricultural University, Ludhiana, 2019) Mandeep Kaur; Ghai, NavitaThe present investigation was conducted to study “Physiological and biochemical changes associated with moisture stress tolerance in maize (Zea mays L.) genotypes”. Twenty genotypes (CML 32, CM 139, CM 140, CM 143, SE 503, SE 544, SE 547, SE 552, I 122, I 132, I 162, I 164, LM 5, LM 11, LM 13, LM 15, LM 16, LM 20, LM 23, LM 24) were screened on the basis of percent survival rate of seedlings under different levels of moisture stress created by withholding 40%, 50% and 60% irrigation. Percent survival of seedlings was noted at 10, 15, 20 and 25 days after sowing at 40%, 50% and 60% moisture stress level and four genotypes: CM 140, LM 16 as tolerant and LM 13, LM 20 as sensitive genotypes were selected out of twenty genotypes. Effects of moisture stress on morpho-physiological and biochemical parameters in tolerant and sensitive maize genotypes along with a check PMH 2 were studied at seedling stage. Morpho-physiological parameters viz. root length, shoot length, root fresh weight, shoot fresh weight, root density, root dry weight, shoot dry weight, root volume, root:shoot ratio, membrane stability, relative leaf water content, chlorophyll content, vigour index I and vigour index II decreased with the moisture stress. However, carotenoid content was found to increase with increasing stress level. The various biochemical parameters viz. proline content, activities of superoxide dismutase, catalase and peroxidase were recorded higher in check PMH 2 and in tolerant genotypes as compared to sensitive genotypes. Also, accumulation of hydrogen peroxide content was lower in CM 140 and LM 16 than LM 13 and LM 20. Under moisture stress, root anatomy showed variations in all the maize genotypes. Density of metaxylem elements increased in all the genotypes as well as in check PMH 2 and more number of root hairs were also in LM 16 and PMH 2. In tolerant genotype CM 140, the diameter of metaxylem also decreased with the drought stress which helped in retention of water in roots under stress conditions. Higher levels of antioxidant enzymes, proline, carotenoid content and decreased hydrogen peroxide might have helped in imparting moisture stress tolerance to CM 140 and LM 16 genotypes. These genotypes can be used by the breeders in further breeding programs.ThesisItem Open Access Effect of tillage, green manuring, rice establishment methods and crop residue management practices on micronutrient uptake and transformation under rice-wheat cropping system(Punjab Agricultural University, Ludhiana, 2018) Mandeep Kaur; Dhaliwal, S.S.The present study was carried out under two on-going field experiments at research farm, Department of Soil Science, Punjab Agricultural University, Ludhiana in split plot design with three replications. The soil of both experimental fields was loamy sand in texture, taxonomically classified as Typic Ustrochrept. The first experiment comprised of twelve treatment combinations among which the main plots consisted of four rice establishment methods viz. direct seeded rice under zero tillage (DSR-ZT), conventional tillage (DSR-CT), reduced tillage (DSR-RT) and puddled transplanted rice (PTR) and three subplots in wheat viz. conventional tillage (CTW-R), zero tillage without rice straw (ZTW-R) and zero till with rice straw (ZTW+R). In this study, soil samples were analyzed for basic chemical indices of soil quality. The DTPA-extractable micronutrient cations (Zn, Fe, Mn and Cu) and their different chemical fractions were analyzed using atomic absorption spectrophotometer (Varion AAS-FS Model). The ZTW+R showed marked increase in concentration of DTPA-extractable Zn, Fe, Mn and Cu and their transformation from occluded fractions towards bio-available forms. Residual fraction of all the micronutrient cations was found to be the most dominant fraction and water soluble + exchangeable fraction was found to be least dominant in soil. Organically bound fraction of all the micronutrient cations studied was found to be most important fraction contributing towards micronutrient uptake by both rice and wheat crops. The ZTW+R produced significantly higher wheat grain yield than ZTW-R. Moreover, rice grain yield under PTR and DSR-RT was comparable but significantly higher than DSR-CT and DSR-ZT. The second experiment consisted of twelve treatment combinations among which the four main plots comprised of puddled transplanted rice with no wheat straw retained (PTRW0), puddled transplanted rice with 25% anchored wheat straw retained (PTRW25), PTRW0 + GM and PTRW25 + GM. Similarly, three subplot treatments included conventional tillage wheat without rice residue (CTWR0) zero tillage wheat without rice residue (ZTWR0) and ZTW with 100% rice residue retained as mulch (ZTWR100) in subsequent wheat crop. The results of the study revealed that soil pH decreased however, SOC and availability of DTPA-extractable micronutrients increased with crop residue retention and GM incorporation in soil. The DTPA-extractable Zn, Cu, Fe and Mn showed sharp decrease from 0-7.5 cm to 7.5-15 cm soil depth and afterwards the decrease was gradual with further increase in soil depth. The transformation of Zn, Cu, Fe and Mn was found higher under PTRW25 + GM treatment from occluded (AFeOx and CFeOx) fractions to mobile (WSEX) ones. Highest productivity and Zn, Cu, Fe and Mn uptake by grain and straw of rice and wheat were also recorded under PTRW25 + GM treatment. In nutshell, green manure incorporation and crop residue retention over the soil surface substantially increased the crop productivity and availability of Zn, Fe, Mn and Cu in soil.ThesisItem Open Access Study on microstructure and pozzolonic properties of fly ash-based geopolymer mortar containing nanometakaolin(Punjab Agricultural University, Ludhiana, 2018) Mandeep Kaur; Jaspal SinghGeopolymerization is a process that can transform alumina-silica rich waste materials into valuable binding materials through alkali activation. Geopolymer binding materials are mainly composed of two components: a source material and alkaline activator liquid. The source material for geopolymer mortar and concrete should be rich in silica and alumina. In this study, fly ash-based geopolymer mortar was prepared by utilizing fly ash as a source material and the mixture of sodium hydroxide and sodium silicate as alkaline activator solution. The present experimental study shed a light on the fluctuations in compressive strength of fly ash-based geopolymer mortar by varying the molarity (M) of sodium hydroxide as 12M, 14M, 16M along with different proportions of nano-metakaolin (NMK) (0% to 10% @ 2% increment by weight of fly ash). The compressive strength was checked subsequently at curing ages of 3, 7, 14 and 28 days. X- ray diffraction test was performed on powder samples of fly ash, S1, S7, S13 and S15. The powder samples of S1, S7, S13 and S15 mix were collected from the remnants of geopolymer mortar specimens after 28 days compressive strength test. It has been observed that the increase in sodium hydroxide molarity and NMK proportion showed considerable improvement in compressive strength of geopolymer mortar at all curing ages. Further, it has been observed that optimum gain in compressive strength is at the 16M molarity of sodium hydroxide containing 4% proportion of NMK. XRD results are in conformity with compressive strength test results.ThesisItem Restricted Fractionation of bay leaf oil and its bioefficacy against root knot nematode Meloidogyne incognita(Punjab Agricultural University, Ludhiana, 2017) Mandeep Kaur; Chahal, K.K.The present investigation deals with Fractionation of bay leaf oil and its bioefficacy against root knot nematode Meloidogyne incognita. The bay leaf essential oil was extracted by hydrodistillation using Clevenger apparatus. GC-MS analysis showed the presence of twenty one compounds. Eugenol, α-Pinene, isoeugenol, caryophyllene and 1,8-Cineole were the major compounds present in bay leaf essential oil. The essential oil was fractionated into its non-polar and polar fractions by column chromatography. α-Pinene, 1,8-Cineole and eugenol were isolated from bay leaf oil. Campholenic aldehyde was prepared from α-pinene and eugenol epoxide was prepared from eugenol using different reagents. The compounds isolated and derivatized were identified using FT-IR, 1HNMR and 13CNMR spectroscopy. The nematicidal activity of bay leaf oil, its fractions, compounds isolated and derivatized was evaluated against Meloidogyne incognita at different concentrations viz.0.20, 0.40, 0.60, 0.80, 1.00, 1.25 and 1.50 mg ml-1 for egg hatch inhibition and juvenile mortality studies. Bay leaf oil, polar fraction and eugenol were found to be very active against. M. incognita whereas αPinene and non-polar fraction showed less activityThesisItem Open Access Alteration of plant architecture and reproductive efficiency of pigeonpea (Cajanus cajan L.) genotypes through growth retardants(Punjab Agricultural University, Ludhiana, 2017) Mandeep Kaur; Jagmeet KaurField experiment was conducted at Punjab Agricultural University, Ludhiana during kharif season in the year 2016-17 with an objective to investigate the effect of ethrel (@ 200 ppm), stance (@ 200 ml/ac) and mepiquat chloride (@ 200 ml/ac) on the growth, flower retention and yield of pigeonpea genotypes PAU 881 and AL 201. The biochemical changes associated with the use of growth substances were also studied. Foliar spray of growth substances were done at 60, 68 and 75 days after sowing. Various morpho-physiological, biochemical and yield characteristics were analyzed at different developmental stages. The plant height reduced effectively with the foliar applications of growth substances. The leaves of treated plants exhibited increased level of chlorophyll, which provided better conditions for higher production of photosynthates to be utilized for grain yield. The parameters determining reproductive efficiency and yield were significantly improved due to reduction in flower abscission, improved flower retention, pod formation, and seed weight. The treatments also affected the various biochemical constituents viz. total soluble sugars, total starch content (leaves and stem), total soluble proteins and amino acids (pod wall and developing seed). The activity of enzymes viz., invertase (stem, leaves, pod wall and developing seed) and sucrose synthase (leaves and stem) also increased in response to growth substances. Ethrel (@ 200 ppm) 60+75 DAS showed the best result among all the treatments.ThesisItem Open Access DEVELOPMENT OF ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA) FOR DETECTION OF MELOIDOGYNE SPP. (ROOT-KNOT NEMATODE) ANTIGENS(PAU, 2010) Mandeep Kaur; Ghai, Jyotika KapurPlant parasitic nematodes are destructive pests worldwide that cause severe losses in agriculture. Root-knot nematodes (Meloidogyne spp.) are obligate, sedentary plant endoparasites that are extremely polyphagous in nature with a wide host range. Keeping in view the huge economic losses by this parasite, it is essential to control the disease at an early stage. For any control strategy to be effective, an early and accurate diagnosis is of paramount importance. Immunoassays have the inherent advantages of sensitivity and specificity; have the potential to identify and quantify these plant-parasitic nematodes. Hence, in the present studies, ELISA has been developed for the detection of Meloidogyne spp. antigens. This is based on detection of egg antigens, for which anti-Meloidogyne antibodies were produced by immunization of rabbits with soluble proteins of the eggs. The production of antibodies was confirmed by the appearance of precipitin lines in double immunodiffusion method. An indirect enzyme-linked immunosorbent assay (ELISA) was developed for detection and titration of these antibodies. Results indicated as high as 320 K titre of the antisera. Finally competitive inhibition ELISA was developed employing these anti-Meloidogyne antibodies for detection of Meloidogyne antigens. This is based on competition between solid phase bound antigens and free antigens for limited antibodies. Sensitivity of ELISA was 10 femtograms. This sensitivity was further enhanced to 1 femtogram with an additional step of pre-incubation, in which antibodies and free antigens are allowed to react before the competition. Competitive inhibition ELISA developed in the present studies has the potential of being used as an easy, rapid, specific and sensitive diagnostic tool for the detection of Meloidogyne infection.ThesisItem Open Access Studies On Seed Rate , Irrigation , Weed Control And Their Interactive Effects In Bed Planted Soybean ( Glycine Max ( L. ) Merrill(Punjab Agricultural University ;Ludhiana, 2003) Mandeep Kaur; Mahey , R. K.ThesisItem Open Access Impact Of Dietary Counselling On Nutritional Status Of Senior Citizen In Punjab(Punjab Agricultural University ;Ludhiana, 2000) Mandeep Kaur; Murgai, V.