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2002 - 200962010 - 20168
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Subject: Botany × End date: 2016 × Start date: 2000 × Type: Thesis × Thesis Type: Ph.D ×
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Now showing 1 - 9 of 14
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    ThesisItemOpen Access
    Morpho-physiological and biochemical characterization of a recombinant inbred line population of rice (Oryza sativa L.) under direct-seeded aerobic conditions
    (Punjab Agricultural University, Ludhiana, 2014) Cheema, Amandeep Kaur; Bedi, Seema
    Direct seeding of rice (Oryza sativa L.) is a resource conservation technology but at the cost of reduction in yield. In the present study, recombinant inbred lines (RILs) obtained from a cross between PR 120 x UPLRi 7 were sown as direct-seeded aerobic and conventional transplanted crops respectively for two seasons. Various morpho-physiological, biochemical and yield related traits were studied under the two conditions. In general, plant height, dry matter, crop growth rate, relative growth rate, leaf area and chlorophyll content were lower under direct-seeded aerobic conditions than under conventional transplanted conditions. Plant height and crop growth rate showed a positive correlation with grain yield and had a direct effect on grain yield. Dry matter accumulation did not show any significant correlation but had an indirect effect on grain yield. Relative growth rate, leaf area and chlorophyll content did not show any correlation or effect on grain yield. All the yield contributing traits viz., above ground biomass, total number of tillers per 0.5m row, number of fertile tillers per panicle per 0.5m row, spikelets per panicle, grain filling percentage, grain yield per 0.5m row, harvest index, 1000 grain weight were lower and sterile grain per panicle were higher in direct-seeded aerobic condition. Above ground biomass and harvest index showed correlation with yield and had a direct effect on grain yield under both direct-seeded aerobic and conventional transplanted conditions. In general, higher sugar, starch and proline content were detected in leaves of direct-seeded aerobic crop. Out of twenty RILs under study, Ae-RIL-B-158, showed highest proline and sugar contents. Interestingly, this RIL showed least reduction in yield when sown under direct seeded-aerobic condition as against conventional transplanted condition suggesting this RIL may be more tolerant to drought stress as it accumulated highest proline and sugars under direct-seeded aerobic condition. The development of aerenchyma was comparatively more in crop raised under conventional transplanted conditions than under direct-seeded aerobic conditions. UPLRi7 (parent) showed maximum aerenchyma under direct-seeded aerobic conditions while PR120 (parent) showed maximum aerenchyma formation under conventional transplanted conditions. Under both the sowing conditions, two high-yielding RILs (Ae-RIL-B-42 and Ae-RIL-B-44) had higher aerenchyma than the two low-yielding RILs (Ae-RIL-B-7 and Ae-RIL-B-117). These characters could be used as criteria for selecting RILs for incorporating into breeding programmes for yield enhancement.
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    ThesisItemOpen Access
    Morphogenetic Studies On Reproductive Development And Yield Potential Regulation In Brassica Juncea
    (Punjab Agricultural University; Ludhiana, 2005) Rai, Jyotsana; Setia, Neelam
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    ThesisItemOpen Access
    Induction Of In Vitro Morphogenesis And Genetic Tranformation Of Cauliflower (Brassica Oleracea L. Var. Botrytis)
    (Punjab Agricultural University ;Ludhiana, 2002) Joshi, Anita; Parmil Singh
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    ThesisItemRestricted
    Physiology Of Yield Development In Chickpea Cultivars And Role Of Plant Growth Regulators In Cold Stress Ameliration
    (Punjab Agricultural University; Ludhiana, 2006) Gurpreet Kaur; Parmil Singh
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    ThesisItemOpen Access
    Morphogenetic Studies On Seed Abortion And Seed Size Variation In Developing Fruit Of Brassica Napus L.
    (Punjab Agricultural University ;Ludhiana, 2003) Harvinder Kaur; Setia, R. C.
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    ThesisItemOpen Access
    Studies On Anatomical Characteristics Of Potato Cultivars Associated With Late Blight Resistance
    (Punjab Agricultural University ;Ludhiana, 2002) Mahajan, Monica; Dhillon, M.
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    ThesisItemRestricted
    Plant Regeneration And Genetic Transformation Studies In Cabbage (Brassica Aleracea Var. Capitata)
    (Punjab Agricultural University ;Ludhiana, 2002) Nanda, Ranjeeta Kaur; Dhillon, M.
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    ThesisItemOpen Access
    Effect of plant growth regulators on manipulation of source-sink relationships in pigeonpea (cajanus cajan l.)
    (PAU, 2013) Pahwa, Kanchan; Ghai, Navita
    Field experiments were conducted at Punjab Agricultural University, Ludhiana during kharif season in the years 2010-11 and 2011-12 respectively with an objective to evaluate various groups of genotypes (early, mid, late and check) on the basis of pattern of growth, partitioning of dry matter, flower retention, growth efficiency and yield and to study the effect of foliar application of ethrel (100 and 200 μg ml -1 ) and cobalt chloride (10 and 15 μg ml -1 ) applied at vegetative and flowering stages on seed yield. Various morpho-physiological, biochemical and yield characteristics were analyzed at different developmental stages. Study conducted with early, mid, late and check genotypes of pigeonpea revealed marked differences in partitioning of assimilates to vegetative and reproductive parts at different stages of growth cycle. The higher CGR, RGR, leaf area, LAI, photosynthesis, stomatal onductance, pod set percentage in mid-duration group resulted in high yield. Further, reproductive efficiency of four mid-duration genotypes (AL 1578, AL 1593, AL 1702 and AL 201) was chemically manipulated by foliar application of ethrel and cobalt chloride. The parameters determining reproductive efficiency and yield were significantly improved due to reduction in flower abscission. Ethrel (100 and 200 μg ml -1) sprayed at vegetative stage and CoCl2(10 μg ml-1) sprayed at flowering stage efficiently improved seed yield and other biochemical traits through improved flower retention, pod formation , seed setting percentage and seed weight. Genotype AL 1578 exhibited high yield in all treatments including control as compared to all the genotypes. The leaves of treated plants exhibited higher level of chlorophyll, which provided better conditions for higher production of photosynthates to be utilized for grain yield due to larger sink resulting from increased branching and number of pods. The treatments also affected the content of various biochemical constituents (total soluble sugars, total soluble proteins, total starch content, total free amino acids, chlorophyll content as well as the activity of various enzymes viz., nitrate reductase (NR), invertase and PEP carboxylase). Correlation analysis showed significant positive relationships between plant height, crop growth rate, leaf area, number of pods/plant, pod set percentage, seed eight/plant, 100-seed weight and harvest index. Further, path analysis revealed leaf area, specific leaf weight and number of pods/plant had significant positive direct influence on yield. Path analysis of various biochemical traits with seed yield revealed that activities of nitrate reductase, total soluble proteins and total starch content in leaves and invertase activity, total starch in seeds showed positive direct effect on seed yield. These traits should be used as target traits to improve seed yield. Protein profiling in mature seeds revealed much denser bands in treated plants as compare to control and also number of bands were higher in treated plants. A study of pedicel anatomy revealed an increase in area of conducting tissues through PGRs application. This increase could be responsible for enhanced translocation of assimilates to flowers, thereby helping in their retention.
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    ThesisItemOpen Access
    Physiological evaluation of source-sink relationships in soybean (Glycine max L. Merrill) genotypes under variable photoperiods
    (PAU, 2014) Dogra, Anil kumar; Kaur, Jagmeet
    Soybean is a short day plant. Both photoperiod and temperature control the duration of pre and post flowering phase and are expected to affect source-sink relationships. The present investigations were aimed at evaluating the relative performance of different maturing group of soybean genotypes with respect to different physiological and biochemical indices for higher productivity under variable photoperiods. To achieve the objectives, field experiments were conducted during kharif seasons of 2012 and 2013 at Punjab Agricultural University, Ludhiana. The experiment were laid out in randomised block design with three replications consisting of 15 genotypes to screen for various morpho – physiological traits, yield and yielding attributes in first year. On the basis of results obtained from the first year experimentation, two genotypes from early maturing genotypes and each of three from medium and late maturing genotypes were selected for biochemical analysis. Morpho-physiological parameters viz., leaf area, leaf area index, leaf and stem fresh and dry weight, net photosynthesis, growth efficiency, chlorophyll content, photochemical efficiency and transpiration rate were affected by photoperiods. Under both the photo-periodic conditions, the late maturing group genotypes maintained higher leaf area, biomass accumulation, leaf area index, photosynthetic rate and transpiration rate as compared to medium and early maturing genotypes leading to higher yield. Under longer photoperiod i.e. June sowing showed more metabolic status as compared to shorter photoperiod (July sowing). Nitrogen metabolizing enzymes viz., GOGAT, GS, GDH and NR activity showed varied response in leaf and stem. Highest activity of these enzymes was found in longer photoperiod as compared to shorter photoperiod. Carbon metabolizing enzyme- invertase also showed varied response in podwall and developing seeds. The activity of this enzyme increased in developing seeds and the highest activity was observed in late maturing genotypes. Finally, it can be concluded that for selection of better genotypes under variable photoperiods, the physiological parameters total dry matter, CGR, RGR, photosynthetic rate, chlorophyll content, LAI, SPLW, 100 seed weight, numbers of pods per plant and harvest index should be considered. These parameters were found to have significant positive correlation with seed yield. Of the evaluated 15 diverse maturing genotypes, the early maturing genotypes EC 457161, medium SL 983 and late SL 958 are superior in terms of yield as well as in other morpho-physiological traits. Of all genotype SL 958 performed the best.