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ThesisItem Embargo Characterization of maize inbred lines for high plant density amenable traits(Punjab Agricultural University, 2024) Meena, Tarun Kumar; Dr Gagandeep SinghIn 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.ThesisItem Restricted Genetic and biochemical characterization among diverse set of Linseed (Linum usitatissimum L.) germplasm(Punjab Agricultural University, 2024) Alka; Dr. Arvinder Kaur ToorThe 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.ThesisItem Restricted Genome wide association studies for sorghum shoot fly and red leaf spot resistance(Punjab Agricultural University, 2024) Jasneet Kaur; Dr. R.S. SohuThe present study was conducted for the assessment of shoot fly and red leaf spot resistance and discovery of markers and candidate genes associated with target traits in Sorghum bicolor across years and locations. A diversity set of 121 germplasm lines, acquired from ICRISAT and IIMR, was evaluated under two environments (two locations – Ludhiana (2020-21 and 2021-22) and Faridkot (2021-22)) for shoot fly whereas at Ludhiana for two years kharif 2020-21 and 2021-22 for red leaf spot disease. The germplasm lines were evaluated for nine morphological traits for shoot fly representing- per cent dead heart formation (DH), glossiness(GL), leaf sheath pigmentation (LSP), plants infested with eggs (PWE), number of eggs per plant (PPE), seedling vigour (SV), seedling height (SDH), plant height (PH) and number of tillers (TL). Significant genetic and genotype x environment interaction variance was observed for all test traits. Ten genotypes viz., IC 288122, IS 7657, IS 7663, IS 7745, IS 8155, IS 8282, IS 8256, IS 8348, IS 8230 and SSV 17 were found resistant and gave stable performance across all environments. Resistant genotype IS 8348 was selected for generation of bi-parental cross with susceptible genotype IS 7017. Similarly, disease score and area under disease progressive curve was used for assessment of red leaf spot disease. Significant genetic variance and genotype x environment interaction variance was observed for disease score under both the environments. Four lines viz., IS 7017, IS 8015, IS 8256 and SCL 4 were free from infection, indicating resistance to red leaf spot. Best linear unbiased predictors values (BLUP) of traits were used for genome-wide association study (GWAS) using 42678 SNPs. Linkage disequilibrium decay in population was estimated to be ~50kb. A large number of significant marker-trait associations were identified for all test traits. The genomic regions identified on chromosomes 1, 2, 4, 7 and 10 were previously reported to be associated with shoot fly resistance for trait DH and GL. Annotations helped to predict candidate genes in the genomic regions associated with the significant SNPs. Important candidate genes involved were receptor kinases (LRR, serine/threonine protein kinases, hydrolases and transferases), stress signalling pathways (ethylene, abscisic acid and jasmonic) for shoot fly and (RLP, WRKY, F-box protein, CDP, zinc finger and putative disease resistance protein) for red leaf spot disease. Associative SNPs were converted into KASP markers and S1_15319241 KASP marker associated with DH was validated in the F2 population of cross IS 8348 x IS 7017.ThesisItem Embargo Phenotypic and molecular evaluation of advanced backcross lines of chickpea (Cicer arietinum L.)(Punjab Agricultural University, 2023) Gopal Krishan; Bindra, ShaylaThe 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.ThesisItem Restricted Development and validation of kaspmarkers for heat stress tolerance QTLs in wheat (Triticum aestivum L.)(Punjab Agricultural University, Ludhiana, 2022) Ranjeet Singh; Dhaliwal, InderpreetA 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.ThesisItem Embargo 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.ThesisItem Restricted Senescence, nutrient remobilization and yield in wheat germplasm introgressed with Gpc-B1 gene(Punjab Agricultural University, Ludhiana, 2022) Jafar Tanin, Mohammad; Sharma, AchlaThe present breeding efforts are required to evaluate a set of germplasm with the Gpc-B1 gene in their genetic background. However, Gpc-B1 is the only recognized and cloned gene which explains 66% of the phenotypic variation for GPC. Therefore, it is essential to enrich our knowledge regarding its role in protein accumulation in wheat grain. On the other hand, the Gpc-B1 has a negative relationship with grain yield. This has made it difficult to create an elite wheat line that has both high GPC and a high yield. The accelerated senescence due to the presence of this gene shortens the grain filling period. We phenotyped the NILs for different phonological and yield-related traits, including number of days to flowering (DTF), plant height (PH), number of spikelets per spike (SPS), 1000-grain weight (TGW), yield, number of days to maturity (DTM), and grain protein content (GPC). An alpha-lattice design was used to do an analysis of variance, which showed that there were significant differences between the genotypes for all of the traits. The Gpc-B1 gene accelerated the flowering time and maturity time by about one day and two days, respectively, as compared to genotypes having no Gpc-B1 gene in their genetic background. Simultaneously, the same gene made the plant shorter by an average of 4.41 cm. The functional Gpc-B1 gene in the genetic background of the NILs increased the protein accumulation in wheat grain through an accelerated senescence and more efficient nitrogen transportation process, which was initiated earlier. But at the same time, the improvement in GPC could result in a grain yield penalty due to a reduction in grain size. A better understanding of how nutrients or chemicals change the function of wheat plants could help breeding programmes in the future. The NILs were evaluated under KNO3 and salicylic acid treatment and control (no KNO3 and salicylic acid application) conditions with the standard fertilizer application rate recommended by PAU for one year (2020–21). A combined analysis of variance using an alpha lattice design was conducted, which indicated significant variation among the studied traits, including DTF, PH, SPS, GPS, DTM, HI, GPC, Yield, and TGW. The potassium nitrate application significantly affected the PH, GPS, DTM, TGW, yield, HI, chlorophyll content in flag leaf at anthesis state and 30 DAA, and other traits. Salicylic acid application significantly affected the number of grains per spike (GPS), 1000-grain weight (TGW), yield, and number of days to maturity (DTM) as compared to the control experiment. This delay had no effect on GPC in NILs, but it did increase yield and traits related to yield, like TGW and GPS. A pooled analysis of variance using an alpha lattice design was conducted, which showed significant variation for all the traits under study. High GPC variation in lines with the same genetic background (PBW550) led to a lot of questions. To find the reasons for this variation, we isolated the high quality RNA of two high GPC NILs and two low GPC NILs. Differential gene expression analysis was carried out on each NIL as a control. A total of 1418 differentially expressed genes (DEGs) were discovered for the selected NIL across all three stages, out of which 1117 genes were upregulated while 301 genes were downregulated. This suggests their probable role in seed development.ThesisItem Open Access Marker assisted development of high yielding wheat combining disease resistance and premium quality(Punjab Agricultural University, Ludhiana, 2021) Pradeep Kumar; Sharma, AchlaDevelopment 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.ThesisItem Restricted Identification of SSR markers associated with Plant Architectural Traits in cowpea (Vigna unguiculata L. walp)(Punjab Agricultural University, 2022) Jain, Mohit; Devinder Pal SinghThe 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.
