Loading...
Thumbnail Image

Thesis

Browse

Search Results

Now showing 1 - 9 of 86
  • ThesisItemEmbargo
    Characterization of maize inbred lines for high plant density amenable traits
    (Punjab Agricultural University, 2024) Meena, Tarun Kumar; Dr Gagandeep Singh
    In temperate maize, breeding for stress tolerance including a higher number of plants per unit area has been extensively used for productivity enhancement in commercial hybrids but this strategy has not been exploited in tropical maize. The increase in the number of plants per unit area through the adoption of high density planting (HDP) is one of the alternative strategies to achieve high productivity in tropical/subtropical maize. Narrow leaf angle, shorter anthesis silking interval, and moderate plant height were delineated as major architectural traits for tolerance to HDP in parental lines. The lines harboring these traits coupled with high grain yield potential under HDP were identified and recommended to use as parents for the HDP breeding program. These are following inbred lines identified for HPD traits CML 451, 221520, EML108, EML113, EML129, PML1112, PML115, PML1194, PML1239, PML133, PML162, PML163, PML164, PML18, PML2, PML80, PML81, SN485145 and VL174449.The inheritance study of leaf angle resulted as the expected number of intermediate, broad leaf angle and narrow leaf angle plants for 9:6:1 was 405, 250 and 607, respectively, giving a chi-square value of 1.097 (< 5.991) hence giving a perfect fit to 9:6:1. Thus, Chi-square analysis revealed that the narrow leaf angle is controlled by two recessive gene. A cross between broad leaf angle (PML1126) and narrow leaf angle (CML451) inbred line was used to raise an F2 mapping population for the construction of two contrasting bulks namely, broad leaf angle (BLA) and narrow leaf angle (NLA). These bulks along with both the parents were sequenced using whole genome resequencing and analysed using the SNP-index method for identifying the narrow leaf angle associated region. Identification of QTLs associated with narrow leaf angle in the material under study based on sequence based bulked segregant analysis and use of QTLseqr software was done. It was observed that the ∆SNP-index values in the region 48.72mb to 55.13mb on chr 6, 44.63mb to 45.74mb; 46.21mb to 50.86mb on chromosome 7, 48.22mb to 54.56mb on chromosome 9 lied outside the statistically calculated confidence interval at 99% level of significance. The findings of the present study will facilitate in genetic dissection of candidate gene(s) responsible for the narrow leaf angle gene. This study will also help in the development of SNP-based markers which would facilitate marker-assisted transfer of narrow leaf angle gene in maize inbred line.
  • ThesisItemRestricted
    Genetic and biochemical characterization among diverse set of Linseed (Linum usitatissimum L.) germplasm
    (Punjab Agricultural University, 2024) Alka; Dr. Arvinder Kaur Toor
    The present study involved the evaluation of sixty linseed genotypes at two locations. Two experiments were conducted, focusing on agro-morphological and biochemical traits. The agromorphological assessment included traits like branches, capsules, seed yield, and maturity duration. Genotype BAU-2019-13 excelled in seed yield at Ludhiana, while LCK-2134 performed best at Gurdaspur. Descriptive statistics indicated minimal environmental impact on most of the traits, suggesting potential for improvement through direct phenotypic selection. Traits like primary branches and seed yield per plant showed high heritability and genetic advance, indicating suitability for improvement through phenotypic selection. Genotype × environment interaction was observed, and GGE biplot analysis highlighted superior performances of LCK-2134 in Gurdaspur and BAU-2019-13 in Ludhiana. Positive correlations were identified between morphological traits and seed yield per plot. Dendrograms revealed six clusters at each location, by grouping genotypes with similar features. These clusters are crucial for breeding programs and for suggesting potential for heterosis. The agro-morphological characterization demonstrated significant genotype variation. The second experiment focused on biochemical traits, including crude protein, oil percentage, and fatty acids. Genotypes with high oil percentage and low anti-nutritional factors were identified as valuable for both human and livestock feeding. The top genotypes for oil percentage and crude protein were Surbhi × LC 2023 and BAU-2021-08, respectively. Genetic variability was confirmed by significant mean sum of squares in the analysis of variance. G × E interaction was significant for tannins and crude protein, while other traits showed non-significant interaction. Dendrograms for biochemical traits classified genotypes based on homogeneity and heterogeneity. The study's comprehensive characterization identified promising genotypes with exceptional performance in both agro-morphological and biochemical traits. This information is valuable for future linseed breeding programs.
  • ThesisItemEmbargo
    Phenotypic and molecular evaluation of advanced backcross lines of chickpea (Cicer arietinum L.)
    (Punjab Agricultural University, 2023) Gopal Krishan; Bindra, Shayla
    The present study entitled “Phenotypic and molecular evaluation of advanced backcross lines of chickpea (Cicer arietinum L.)” was conducted to incorporate the genes for FW resistance from WR315 in PBG7 and for AB resistance from ILC3279 in L552. A set of 35 lines and 20 lines from Cross I (PBG7 × WR315) and Cross II (L552 × ILC3279) respectively, were phenotyped during rabi 2021-22 and 2022-23 along with their molecular evaluation. Analysis of variance, evinced significant difference for all the traits among the backcross derived lines. The PCV values were observed to be slightly greater than the corresponding GCV values for all the characters studied in both the crosses, indicating the influence of the environment for the expressions of the traits. In both the crosses PCV and GCV values were recorded to be maximum for seed yield per plant. High heritability coupled with moderate genetic advance was observed for seed yield per plant in Cross I while in Cross II, it was for seed yield per plant, aerial biomass and number of pods per plant. Correlation studies revealed positive and highly significant correlation of seed yield per plant with harvest index and aerial biomass, both for Cross I and Cross II. In Cross I highest positive direct effect of harvest index was for seed yield per plant whereas, for aerial biomass in cross II. Based on screening for disease resistance, a total of eight lines of Cross I for FW and four lines of Cross II for AB were found to be resistant. A total of six linked markers (GA16, TAA60, TA194, TS82, TA110 and TR19) for FW and eight (GA16, TS82, TA194, TR58, GAA47, SCY17, TA130 and TA2) for AB were used for foreground selection. To estimate background genome recovery, a total of 40 and 45 SSR markers were used for Cross I and Cross II, respectively. The GGT analysis for Cross I revealed the RPG recovery as high as 93.75% while in Cross II with 98.88%. Overall, two lines each of Cross I (GLMFW02 and GLMFW10) and Cross II (GLMAB06 and GLMAB07) with maximum RPG recovery were found to be promising for yield and related traits under study.
  • ThesisItemRestricted
    Development and validation of kaspmarkers for heat stress tolerance QTLs in wheat (Triticum aestivum L.)
    (Punjab Agricultural University, Ludhiana, 2022) Ranjeet Singh; Dhaliwal, Inderpreet
    A panel of 24 wheat genotypes, comprising 19 heat tolerant, 3 heat susceptible and 2 parental lines were evaluated under timely and late sown conditions during rabi 2020 in a Randomized block design with an aim to develop and validate a KASP assay for heat stress tolerance. Eleven major reproductive traits, including grain yield, plant height and days to maturity were evaluated. In general, there was a reduction in grain yield under late sown compared to timely sown conditions. This trait was highly variable among the 24 genotypes as some of them (KSG1188, KSG089, KSG849, KSG1189 and KSG1195) exhibited very low reduction in yield, indicating a tolerance to heat stress for maintaining the desired yield levels. Similar behavior was observed for other plant traits also, viz, days to heading, days to maturity, mean grain weight per main spike, spikelet fertility and tiller number per meter square. There were also some genotypes that displayed increased height and biomass under late sown conditions, which is rare for a heat stressed crop. The stability in performance of the genotypes may be attributed to heat stress tolerance under late sown conditions. Since the QTL for stress tolerance were already described in an earlier study, the identified GBS-SNPs were converted to 4 KASP primers following standard procedures to run the KASP assay on this panel. Of these four primers, 2 were successful in allele calling, thereby giving an efficiency of 50%. Hence, converting these identified GBS-SNPs into KASP assays can successfully be used to differentiate the genotypes or populations for heat stress related QTL.
  • ThesisItemEmbargo
    Phenotypic and molecular characterization of rice (Oryza sativa (L.)) genotypes for grain zinc content
    (Punjab Agricultural University, 2022) Phyo, Su Hlaing; Mangat, G. S.
    Biofortification is one of the most sustainable strategies to alleviate micronutrients deficiencies for people who mainly consume rice and have limited access to diversified food. The present study aimed at evaluating a set of 160 advance breeding lines along with check varieties for various yield attributes, quality traits and grain zinc content at Ludhiana and Rauni. These were evaluated for days to 50 % flowering, plant height, ear bearing tillers per square metre, spikelets sterility, number of spikelets per panicle, thousand grain weight and grain yield, milling quality and grain zinc content. Significant genotypic variation was present for various traits at both locations. Most of the genotypes were early to medium in maturity with semi dwarf plant height and good tillering ability. Significant variation for head rice recovery was present and it ranged from (41.7 to 67.6%). The zinc content in brown rice ranged from 17.1 to 35 ppm and in polished rice from 12.3 to 29.7 ppm. The genotypes PAU 8182-205-2, PAU 8182-205-1, PAU 8182-108-1, PAU 8182-116-1, PAU 8182-150-1, PAU 8182-182-1, PAU 8182-112-5, PAU 8182-171-4, PAU 8182-175-1 and PAU 8182-215-1 had high grain zinc content of more than 24 ppm in polished rice. Grain yield was negatively correlated (-0.208** and -0.185*) with grain zinc content in brown rice and polished rice. Molecular characterization of advance breeding lines with known markers for high zinc contents did not reveal much variation as most of the primers showed monomorphic banding pattern. Zinc rich elite genotypes with desirable ancillary traits may serve as potential donors for biofortification breeding programme.
  • ThesisItemOpen Access
    Marker assisted development of high yielding wheat combining disease resistance and premium quality
    (Punjab Agricultural University, Ludhiana, 2021) Pradeep Kumar; Sharma, Achla
    Development of end product specific wheat germplasm is the comparatively newer objective in wheat breeding programme. Wheat breeding programme in our country has mainly focused on yield and resistance breeding. There has been no dedicated chapati quality breeding programme in until recent past. The present study aimed to decipher the basis of chapati quality and to develop premium quality wheat germplasm carrying high levels of stripe rust resistance and leaf rust resistance through pyramiding of Lr57/Yr40 and Yr15 rust resistance genes in premium chapati quality background. Analysis of chapati quality traits in specially constituted core set of wheat genotypes at multilocations of the state revealed that the environment in which wheat is grown has significant effect on grain quality. The major components of chapati making quality include various components such as dough handling, chapati colour, texture, flavor, taste, sweetness pliability etc. and should be given due weightage for deriving a composite chapati score. Chapati quality traits protein content (0.143), hectoliter weight (0.278), thousand grain weight (0.474), sedimentation volume (0.194), gluten index (0.260), water absorption (0.359), puffing height (0.302) were found to be positively correlated with overall chapati score. The negative correlation was found for phenol score (-0.149), water loss after baking (-0.198) and water loss after 4 hour (-0.380) with chapati score. The farinographic traits showed genotypic difference among genotypes. Identification and selection based on quick and reliable traits in segregating populations of targeted crosses is very important to develop germplasm with specific quality traits. In the segregating population, the F2 and F3 homozygous pyramided plants were identified for both the genes Lr57/Yr40 and Yr15 using KASP and SSR markers, respectively. The plants homozygous for both of the genes were further analyzed for agronomic and quality traits.
  • ThesisItemRestricted
    Identification of SSR markers associated with Plant Architectural Traits in cowpea (Vigna unguiculata L. walp)
    (Punjab Agricultural University, 2022) Jain, Mohit; Devinder Pal Singh
    The objective of the present investigation was to estimate genetic variation and type of gene action controlling morpho-agronomic traits of two cowpea crosses viz., C-88 x TNFC 6926 and CL400 x C-74. The data for six populations viz., Parental lines their FI, F2, BC and BC were collected for evaluation. The observations were recorded for different morphological attributes viz; plant height (cm), vine length (cm), number of leaves, leaf length (cm), leaf width (cm), green fodder yield (kg/plot), dry matter yield (kg/plot), crude protein (%), acid detergent fibre (%), neutral detergent fibre (%) and in vitro dry matter digestibility (%).Simple- additive model was tested to check the adequacy and presence of epistatic interactions. The scaling test shows significant results for most of the traits for both crosses which indicated the presence of epistatic interactions. When the simple additive - dominance model was inadequate, the data were subjected to the six parameter model which included digenic epistatic effects. The results indicated that the mean effect is highly significant and the traits were quantitatively inherited. Additive and dominant gene effects are highly significant for most of the traits under investigation. The high magnitude of additive x additive gene effect for green fodder yield suggests the pedigree method best suitable breeding programme for development of cultivars with better fodder quality traits. ldentification of SSR primers associated with plant type was conducted on F: population of Cross I (C-88 x TNFC 6926). 151 SSRs were employed for Bulk Segregant Analysis (BSA), out of which 15 SSRs showed polymorphism. These SSR primers can be utilised in future for the selection of semi-erect plant types from large Fa population. Semi-erect plant types can be grown along with other non-legume crops for getting nutritious fodder.
  • ThesisItemRestricted
    Promoter polymorphism and development of molecular markers for FAD2 genes associated with oleic acid content in Brassica juncea L.
    (Punjab Agricultural University, 2023) Manpreet Kaur; Sunayana
    This study was undertaken to investigate the functional copies of the FAD2 gene that contribute to the formation of high oleic acid through expression profiling in low and high oleic acid groups of B. juncea. Subsequently, the promoter region of the functional FAD2 gene was extracted and analysed to identify sequence variations within both LOA and HOA groups using multiple sequence alignment. Molecular markers were developed using the identified variability in the promoter region and then validated on the F2 population derived from the cross between LOA (RLC3) and HOA (HOJ 93-1) cultivars. Three distinct functional copies of the FAD2 gene are situated on chromosomes A05 (BjuA.FAD2.a2), B01(BjuB.FAD2.b1) and B05 (BjuB.FAD2.b2) in B. juncea. The gene expression of BjuA.FAD2.a2 and BjuB.FAD2.b2 exhibited a higher fold change value in comparison to low and high oleic acid genotypes. The expression of BjuB.FAD2.b1 gene has an almost similar expression in diverse oleic acid genotypes. For the functional characterization of the promoter region of the FAD2 gene HOJ 93-6, HOJ 93-1 and RLC3, having high and low oleic acid content were outsourced for re-sequencing. Multiple sequence alignment indicated nucleotide variation only for BjuA.FAD2.a2 and BjuB.FAD2.b1 gene. No nucleotide variation was detected within BjuB.FAD2.b2 gene. SSR and CAPS makers were designed to facilitate marker assisted selection for high oleic acid content. After the validation of markers on parents and the F2 population, three distinct classes were observed for inheritance studies. The first category was characterized by oleic acid content exceeding 58%, the second displayed intermediate oleic acid levels of 46-56% and the third category exhibited low oleic acid content ranging from 40% to 45%. Inheritance studies indicated that the regulation of oleic acid content was governed by two FAD2 gene copies which are present at the A05 and B01 chromosome.
  • ThesisItemRestricted
    Characterization of High Grain Weight Introgression Lines Derived From Wild Tetraploid Triticum dicoccoides (AABB) In Wheat.
    (Punjab Agricultural University, 2023) Paramjot Singh; Mavi, G.S.
    Bread wheat (Triticum asetivum L., AABBDD, 2n= 6x= 42) belongs to family Poaceae, one of the most critical food crops. As the population is increasing day by day, therefore demand of food is increasing. The challenge before the scientist is to increase the production of food crops as the land for cultivation is decreasing due to population boom. So, scientists are exploring the wild accessions of wheat as these have wide variation for the traits related to yield enhancement. Yield is the complex quantitative trait, the genetic × environmental (G × E) interaction has significant impact on it. In contrast to its seed weight, which is formed of individual grain size, morpho-metric components of grain area, length, and width, is shown to be more stably inherited than final yield. T. diccocoides represents great genetic variation for grain length, which could be used as an important resource in the wheat improvement. In the current study, 13 wild accessions of T. diccocoides available with PAU were used to cross with six hexaploid wheat genotypes, namely PBW723, WL711NN, PBW621, PBW343, HD2967 and WH1105. Selections were made for plants that were showing high grain parameters like grain length, grain width and thousand grain weight and these selected plants were advanced up to BC2F6 generation. In BC2F5 and BC2F6, phenotypic data of BILs were taken related to grain length, grain width, thousand grain weight, plant height, spike length, spikelet per spike. Analysis of variance revealed the presence of variability for all the traits. The broad sense heritability and genetic advance over mean revealed that traits spike length and thousand grain weight have high broad sense heritability and genetic advance over mean, so selections for these traits will be performed from the BILs. Further, correlation study revealed that grain length and grain width have significant and highly positive correlation with thousand grain weight. The introgression profiling was done for the BILs. For profiling of the BILs 214 SSR markers were used. In each chromosome around 15 to 20 markers were applied that were present along the whole chromosomes. The 71 markers were polymorphic on parents and these were amplified on BILs, 40 markers were found polymorphic. The comparison was made with BILs with low and high grain length and grain width. Majority of introgressions were found on the B genome, primers WMC336, WMC757, WMC128, WMC673, WMC597, GWM644, WMC459 and WMC76 were found introgressed in the BILs that were having high grain length and grain width. The protein content of the BILs was varying from 6% to 15.44%. BILs TD-8, 14, 15, 20 were selected as best performing BILs after analysing both years data.