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ThesisItem Open Access Combining Ability Analysis for Yield and Yield Components in Lentil (Lens culinaris Medik.(G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2023-06) Ansari, Raees; Verma, S. K.Lentil (Lens culinaris Medik) is a major pulse crop grown in the rabi season, which contributes significantly to the nutritional security of the country. The present investigation was undertaken at Pulse Breeding Block of N. E. Borlaug Crop Research Centre, GBPUA&T, Pantnagar, Uttarakhand, India, during rabi 2020-21 and 2021-22 crop season to estimate combining ability and gene action, to determine the magnitude of heterosis and to study the morphological and molecular diversity among the lentil genotypes. Eight genotypes were used as parents and were crossed in all possible combinations in a half diallel fashion (excluding reciprocals) to produce 28 F1 hybrids during the rabi crop season of 2020-21 and evaluation of 28 F1 hybrids, along with eight parents and one check DPL 62 during the rabi crop season of 2021-22. The observation on seven different morphological characters were recorded on five randomly selected plants from each replication and the appropriate statistical methods were used to draw the conclusion. ANOVA for diallel analysis resulted in significant mean sum of square due to parents and hybrids revealing the presence of considerable variability among them. The estimates of σ² SCA were found to be higher than the σ2 GCA for days to 50 % flowering, days to maturity and number of primary branches, while for rest of the characters σ2 GCA were higher as compared to σ² SCA. Higher SCA than the corresponding GCA indicates the presence of dominance gene action or non-additive gene effects. The Parent PL 7 was found to be good general combiner for maximum number of six characters including seed yield per plant (g). The cross PL 7 x LH 84-8 had good SCA effects for a maximum five number of traits including seed yield per plant (g). Among twenty-eight hybrids, nine hybrids i.e., PL 8 x PL 7 (41.50%), PL 8 x PL 5 (30.28%), PL 8 x PL 406 (27.10%), PL 8 x L 4147 (18.13%), PL 8 x PL 4 (17.94%), PL 8 x PL 639 (15.70%), PL 5 x PL 7 (14.21%), PL 7 x LH 84-8 (12.90%), PL 7 x L4147 (11.21%) revealed positive and significant standard heterosis over check DPL 62. Mahalanobis D2 statics, grouped 25 genotypes of lentil into five different clusters. The cluster I is the largest cluster contain 15 genotypes followed by cluster II and cluster III (4 genotypes each), whereas cluster IV and V each retained one genotype. Based on the inter-cluster distance, genotypes present in cluster III (DPL 62, IC 201798, EC 1 and ILWLS 118-1) and cluster V (PL 406) were recognized as genetically most divergent. Therefore, these genotypes can be hybridized and superior transgressive segregants can be obtained in segregating generations. Based on the cluster means genotypes present in cluster V (PL 406) was identified as a potential donor to obtain superior recombinants concerning seed yield and its contributing traits. Molecular diversity among 25 elite genotypes was carried out using 20 SSR markers. Out of these 20 SSR markers, four markers were found polymorphic. Polymorphic information content (PIC) value ranged from 0.855 (SSR 107) to 0.538 (SSR 156) respectively. The analysis of dendrogram revealing the relationship among 25 lentil genotypes. Jaccard similarity coefficient ranged from 0.45 to 0.82 among 25 genotypes. The super cluster is divided into two sub clusters A and B at Jaccard similarity coefficient of 0.45. Cluster A is further divided into two cluster A1 and A2 at Jaccard similarity coefficient of 0.59, each containing 12 genotypes. Cluster B contains only one genotype IC 201798, which found to be most diverse from rest of the genotypes. There is no direct relationship between morphological and molecular diversity as the genotypes those are grouped in same cluster on the basis of morpholog ical diversity, grouped into different clusters on molecular diversity basis.ThesisItem Open Access Genetic analysis for grain yield and morphophysiological traits in bread wheat (Triticum aestivum L.em. Thell)(G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2023-07) Mehra, Ayushi; SwatiThe present investigation was conducted to study the genetic diversity, combing ability, and heterosis for grain yield and its components using phenotypic and molecular screening of wheat genotypes. Thirteen lines and three tester were crossed in Line × Tester mating design during the Rabi season 2021-2022 in Norman E. Borlaug Crop research center of G. B. Pant University of Agriculture and Technology, Pantnagar. In the Rabi season 2022-2023, field experiment with 45 genotypes comprising 13 parents, 30 F1, and two check variety viz. HD2967 and DBW 187 were laid down in a randomized block design with three replications. Nineteen characters were taken under study i.e., days to 75 % heading, days to maturity, NDVI, canopy temperature, chlorophyll content, flag leaf area, spike length(cm), peduncle length(cm), plant height (cm), number of productive tillers/ plant, awn length(cm), number of spikelets per spike, 1000 grain weight(g), biological yield/plant(g), grain yield/plant(g), harvest index, number of grains per spike, grain weight per spike, and leaf orientation value. Genotypes were phenotypically screened for disease reactions under epiphytotic conditions, along with molecular screening to detect the presence of major Yr genes. Statistical analysis revealed a significant difference among the genotypes for all characters. Variance due to sca was higher than that due to gca for all the characters, indicating the predominance of non-additive gene action. DWAP 182 emerged as a good general combiner for the maximum number of traits (eight): days to 75 % heading, CTD at anthesis, chlorophyll content after 15 days of anthesis, number of productive tillers per plant, biological yield per plant, grain yield per plant, harvest index, and number of grains per spike. Among the testers, DBW 222 showed a significant gca effect on chlorophyll content after 15 days of anthesis, flag leaf area, biological yield per plant, number of grains per spike, and grain weight per spike. DWAP 182 × UP 2938 and UP 2993 × DBW 222 turned out to be good specific combiners for the maximum number (10) of traits. DWAP 182 × UP 2938 emerged as a good specific combiner for NDVI after 15 days of anthesis, CTD after 15 days of anthesis, flag leaf area, number of productive tillers per plant, thousand grain weight, biological yield per plant, grain yield per plant, number of grains per spike, grain weight per spike, and leaf orientation value, whereas UP 2993 × DBW 222 turned out to be a good specific combiner for CTD after 15 days of anthesis, chlorophyll content at anthesis, number of productive tillers per plant, awn length, biological yield per plant, grain yield per plant, harvest index, number of grains per spike, grain weight per spike, and leaf orientation value. UP 2993 × DBW 222 found to be the best specific combiner with significant gca for chlorophyll content at anthesis, number of productive tillers per plant, biological yield per plant, grain yield per plant, and grain weight per spike. For NDVI after 15 days of anthesis, canopy temperature depression after 15 days of anthesis and 1000 grain weight, cross DWAP 182 × UP 2938 was considered to be the best specific combiner. WH 1251 × UP 2903 appeared to be the best specific combiner with the highest significant sca values for leaf orientation value, whereas HI 1612 × DBW 222 emerged to be the best specific combiner with significant sca effect for spike length and number of spikelets per spike. Relative heterosis, heterobeltiosis, and standard heterosis were estimated for all the characters. DWAP 182 x UP 2938 emerged out to be the best cross which had shown significant positive heterosis over mid parent, better parent and checks HD 2967 and DBW 187 for NDVI at 15 days after anthesis, canopy temperature depression at 15 days after anthesis, number of grains per spike, biological and grain yield per plant whereas, UP 2993 x DBW 222 emerged out to be the best cross which had shown significant positive heterosis over mid parent, better parent and check. HD 2967 and DBW 187 for chlorophyll content at anthesis, flag leaf area, number of productive tillers per plant, awn length, number of grains per spike, grain weight per spike, biological and grain yield per plant. Based on the ACI under artificially inoculated field conditions, all genotypes were classified as resistant, intermediate, or susceptible. Molecular analysis using linked SSR primers Xwmc175 revealed the likely presence of the Yr5 gene in Avocet/Yr5, DBW 233, DWAP 182, HD 3337, and UP 2993. These five genotypes also showed resistance response in field conditions. After further investigation, these genotypes could be used as donor parents in rust- resistance breeding programme.ThesisItem Open Access Heterosis and combining ability studies for yield and its component traits in Lentil (Lens culinaris Medikus(G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2023-04) Kelwal, Tripti; Verma, S. K.The present investigation was undertaken at Pulse Breeding Block of N. E. Borlaug Crop Research Centre, GBPUA&T, Pantnagar, Uttarakhand, India, during rabi 2021-22 and 2022-23 crop seasons to estimate combining ability, gene action and heterosis; genetic parameters and genetic diversity in lentil. A half diallel involving eight parents were used to produce 28 F1’s during rabi 2021-22. All the 37 genotypes including 8 parents, 28 F1’s and one check variety, PL 9 were evaluated in a Randomized Complete Block design (RBD) with three replications during rabi crop season of 2022-23. The observation on 8 different morphological characters were recorded and the appropriate statistical methods were used to draw the conclusion. ANOVA for diallel analysis resulted in significant mean sum of square due to parents and hybrids revealing the presence of considerable variability among them. The estimates of σ² SCA were found to be higher than the σ2 GCA for the traits days to 50% flowering, days to maturity, plant height and number of primary branches per plant, while for rest of the characters σ2 GCA were higher as compared to σ² SCA estimates. Higher SCA than the corresponding GCA indicates the presence of dominance gene action or non-additive gene effects as SCA is a function of dominance effect whereas, high GCA indicating the preponderance of additive gene action. The parent DPL 62 was found to be a good general combiner for five traits viz., days to 50% flowering, days to maturity, plant height (cm), 100-seed weight (g) and seed yield per plant (g). The hybrids PL 4 x PL 8 and PL 8 x L 4147 had good SCA effects for maximum seven characters viz., days to 50% flowering, days to maturity, plant height, number of primary branches, number of pods per plant, 100- seed weight and seed yield per plant. The standard heterosis for seed yield per plant over the check PL 9 ranged from -46.85% (PL 4 x L 4076) to 30.45% (PL 8 x DPL 62). Among the 28 hybrids, only five hybrids revealed significant and positive standard heterosis over the check variety PL 9 i.e., PL 8 x DPL 62, PL 8 x L4147, PL 8 x DPL 15, PL 8 x LH 84-8 and PL 8 x L 4076. Genetic variability, inter-character association, path coefficient analysis and genetic divergence were studied in 25 lentil genotypes during rabi 2022-23. High PCV and GCV estimates were recorded for characters viz., seed yield per plant, primary branches/ plant, 100 seed weight, seeds per pod and pods per plant. High estimates of heritability coupled with high genetic advance as per cent of mean were observed for the traits plant height, primary branches per plant, pods per plant, seeds per pod, 100-seed weight and seed yield per plant which may be attributed to the preponderance of additive gene action and possess high selective value and thus, selection pressure could profitably be applied on these characters for their rationale improvement.The traits plant height and number of pods per plant had positive significant association with seed yield per plant at both genotypic and phenotypic level.These traits can be enhanced by selection, which will ultimately improve the economic yield per plant. Path coefficient analysis suggested that the trait pods per plant had high direct effect and positively correlated with seed yield. Mahalanobis D2 statics, grouped 25 genotypes of lentil into five different clusters. The cluster I is largest containing 12 genotypes followed by cluster II with 10 genotypes and cluster III, IV and V with a single genotype each. Maximum inter-cluster distance was recorded between Cluster I and V (36.108) indicating that genotypes from these clusters were highly divergent meriting their consideration in selection of parents for hybridization. Based on the cluster means genotypes present in cluster II (PL-07, PL234, LL931, LL875, PL-05, K75, PL639, PL12, PL11 and KLS218) showed that the genotype in these cluster can be selected as early maturity in lentil breeding programme. Molecular diversity among 25 elite lentil genotypes was carried out using 20 SSR markers. Out of 20 markers, five markers were found to be polymorphic. SSR 156 was found to be most informative marker as it recorded maximum PIC value of 0.696 and can be utilized for diversity analysis in lentil. The analysis of dendrogram revealing the relationship among 25 lentil genotypes. Jaccard similarity coefficient ranged from 0.45 to 0.94 among 25 genotypes. Clustering patterns obtained from the dendrogram clearly resolved the 25 genotypes into four distinct clusters. Cluster III was the largest cluster having 13 genotypes, followed by Cluster IV (7 genotypes), Cluster I (3 genotypes) and Cluster II (2 genotypes). There is no direct relationship between morphological and molecular diversity as genotypes those are grouped in same cluster on the basis of morphological diversity, grouped into different clusters on molecular diversity basis.ThesisItem Open Access Identification of the genomic regions contributing for heat stress tolerance in wheat (Triticum aestivum L. em. Thell) under multi environmental conditions(G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2023-02) Patil, Meghashri S; Jaiswal, J. P.Wheat is the third most important cereal crop grown worldwide which provides 25% - 50% calorific needs of growing human population and is the staple source of diet for millions of people all over the world. With the ever increasing global average temperature, wheat is considerably subjected to heat stress. Heat stress tolerance is a stage-specific and developmentally regulated quantitative trait. Hence genetic dissection of this quantitative trait through QTL mapping Mendelizes trait behaviour thus easing the selection and improvement for heat stress tolerance. In the present investigation, 192 Recombinant Inbred lines (RILs) derived from the cross between PBN51 and Raj4014 were evaluated under multi environmental conditions (GBPUAT, Pantnagar, BHU, Varanasi and SKUAST, Jammu) for QTL mapping for different morpho-physiological and yield traits viz days to heading (DH), days to maturity (DM), grain filling duration (GFD), plant height (PH), spike length (SL), number of spikelets per spike (SPS), number of grains per spike (GPS), number of productive tillers per meter (TPM), grain weight per spike (GWPS), thousand grain weight (TGW), grain yield per plot (YPP), canopy temperature depression (CTD), Normalised difference vegetation index (NDVI) and relative chlorophyll content. In correlation studies, grain yield per plot showed significant positive correlation with TGW, GWPS, TPM, SPAD (at pre booting stage), GPS, CTD (at heading stage), GFD, PH and was found to be negatively correlated with DH. Genotype and Genotype x Environment interaction analysis by GGE biplots revealed that the lines 143, 5, 132, 97 and 156 were ideal as they had higher mean grain yield per plot as well as stable across environments. Among the environments, Jammu_2017-18_LS was found to be more representative of the genotypes for YPP. For QTL mapping, the RILs were genotyped with 83 polymorphic SSR markers and genetic linkage map was created using ICIM v4.2 software. Through Inclusive Composite Interval Mapping, a total of 31 QTLs with LOD scores more than 3.0 were identified on 21 genomic regions across 14 chromosomes with chromosome 1A harbouring 4 QTLs. Among these, 6 QTLs were found to be major, explaining PVE of more than 9%. These QTLs are designated as QGfd.pant_5B, QGps.pant_1A, QGps.pant_3A, QGwps.pant_1A, QTgw.pant_7A-1 and QTgw.pant_7D. Under multi-environmental evaluation, 10 QTLs were found to be consistent across two or more environments and 4 genomic regions on chromosomes 1A, 3A, 5B and 7D were found to be associated with two or more traits. The QTLs thus identified can be used in marker assisted selection after fine mapping and validation.ThesisItem Open Access Principal Components of Yield and Quality Parameters in Sugarcane (Saccharum spp. Complex)(2023-06) Pandit, Praati; Jeena, A. S.The present investigation entitled “Principal Component of Yield and Quality Parameters in Sugarcane (Saccharum spp. Complex)” was conducted with 19 clones of Sugarcane including three checks viz., CoS 767, CoPant 97222 and Co 05011. The study aimed to investigate various genetic parameters such as variance components, correlation coefficients, path coefficients and principal component of yield and quality traits. The experiment was conducted in randomized block design with three replications at Norman E. Borlaug Crop Research Centre of Govind Ballabh Pant University of Agriculture and Technology, Pantnagar. Data was recorded for 16 yield and quality attributes of sugarcane viz., germination percent at 45 days, number of tillers (000/ha) at 120 days, number of millable canes (000/ha) at 300 days, Stalk length (m), Stalk diameter (cm), single cane weight (kg), Brix percent, sucrose percent, juice purity percent, Commercial Cane Sugar percent (at 10-months and 12-month stage), Commercial Cane Sugar yield (t/ha) and Cane Yield (t/ha) and subjected to statistical analysis as per the objective of study. Analysis of variance revealed that genotypes exhibited highly significant variation for ten characters indicating ample scope for selection of genotypes for improvement in cane yield. The higher PCV than GCV for all of the traits indicated environmental influence on these traits. Correlation coefficient revealed that cane yield was significantly and positively correlated with germination percent, number of tillers (‘000/ha), number of millable canes (‘000/ha), stalk length(m), stalk diameter(cm), single cane weight(kg) and CCS yield at both genotypic and phenotypic level. The highest positive and direct effect on cane yield was recorded with by CCS yield followed by number of millable canes and single cane weight. It indicated that, direct selection would be more useful for these characters to improve cane yield. Principal Component Analysis (PCA) revealed that first three principal components accounted for 84.1% of the total variation in the tested breeding material. Principal component analysis was performed to characterize the nineteen genotypes. Among them PC (2014-15)- 164, PC (2013-14)-338, PC (2014-15)-240, PC (2013-14)-276, CoPant 97222 and Co 05011 were found to be superior genotypes with respect to vegetative growth parameters as well as cane yield, while genotypes such as PC (2014-15)-164, PC (2013-14)-61 and PCMS (2014-15)- 74 were found to be best with respect to cane yield only. The genotypes PC (2014-15)-289, PC (2013-14)-338 and PC (2013-14)-547 were found to be best performing for quality parameters in sugarcane.ThesisItem Open Access G×E Interaction and Genetic Diversity Studies for Seed Yield and Attributing Traits in Advance Lines of Brassica juncea L. Czern and Coss.(2023-05-01) Sahu, Sabyasachi; Tewari, S. K.The present investigation was carried out in rabi season of 2019-20, 2020-21 and 2021- 2022 with objectives to to study G x E interaction and varietal stability by using AMMI model, nature and extent of Genetic Variability and Heritability, Genetic Divergence ,nature and magnitude of association and direct and indirect effects of various seed yield and attributing traits in Brassica juncea L. Czern and Coss. at N.E.B.C.R.C. and oilseed lab of Department of Genetics and Plant Breeding at G.B.P.U.A. &T., Pantnagar. The experimental material comprised of fourty four advance lines including checks, sown in Randomised Block Design with 3 replications. For this investigation eleven traits namely days to maturity, plant height, length of main raceme, siliquae on main raceme , number of primary branch, number of secondary branch, siliqua length , number of seeds/siliqua,1000 seed weight, oil content and seed yield were observed for five randomly selected competitive plants. The resulting data were subjected to statistical analysis. The result of analysis of variance revealed that difference among mustard lines was highly significant for all the characters. The G x E interaction and varietal stability of mustard lines were estimated by using AMMI model and it was observed that the main effect as well as G x E interaction effect was significant for all the traits under study. AMMI model having two principle components axis (IPCA I and IPCA II) is genotype PRE-2020-1 for seed yield were considered as most stable genotypes in all the environments. Highest GCV and PCV estimates were exhibited by number of secondary branches, number of primary branches, 1000 seed weight, seed yield. High heritability and high genetic advance as percentage of mean reported in the character number of secondary branch, 1000 seed weight. High positive significant correlation for seed yield reported by plant height, length of main raceme, siliquae on main raceme, number of primary branches. Path coefficient analysis showed that the characters length of main raceme, number of primary branch and 1000 seed weight exhibited positive direct effects on seed yield per plot and these traits also recorded positive correlation with yield. The D2 analysis was carried out for eleven characters, which partitioned the fourty four genotypes into twelve highy divergent clusters. On the basis of the study conducted, it was concluded that there was a wide range of variance between the genotypes which was considered as scope for improving the mustard lines through selection. On the basis of the mean performance of the genotypes, the advance lines found to be most promising are PRE-2020-12, PAB-2017-3, PRE-2019-5, PRE-2019-5, PAB-2014-4, PRL-2020-5, PRE-2018-1, PR-2020-16, PRE-2019-5 and PR-2020-9 for seed yield and its attributing traits which can be used for hybridization programme.ThesisItem Open Access Stability analysis in advanced clones of sugarcane Saccharum spp. complex(G. B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand. PIN 263145, 2022-08) Goswami, Riya; Jeena, A. S.The present investigation entitled “Stability analysis in advanced clones of sugarcane (Saccharum spp. complex)” was conducted with 18 advanced clones of Sugarcane including three checks viz., CoS 767, CoPant 97222 and Co 05011 to estimate the genotype×environment interaction and stability parameters using Eberhart and Russell model. The experiment was conducted in randomized block design at three different environments viz., Norman E. Borlaug Crop Research Centre of Govind Ballabh Pant University of Agriculture and Technology, Pantnagar (E1), U.P Council of Sugarcane Research, Shahjahanpur (E2) and, PAU Regional Station, Kapurthala (E3). At each environment observations were recorded for fifteen yield and yield contributing traits viz., germination percent, tillers/ha, brix percent at 10 months, purity percent at 10 months, sucrose percent at 10 months, number of millable cane/ha, single cane weight (kg), cane diameter (cm), cane height (m), cane yield (t/ha), CCS yield (t/ha), brix percent at 12 months, sucrose percent at 12 months, purity percent at 12 months and CCS percent at 12 months. Analysis of variance at each environment revealed that genotypes exhibited highly significant differences for all characters under study. Further, the pooled analysis of variance over three environments also exhibited significant differences among genotypes for all the fifteen traits. The estimates of the environmental index showed that E1 was the most favourable environment for nine traits followed by E2 for seven traits and E3 for five traits. Based on the mean performance, CoPant 97222 was registered as the best check for nine traits followed by CoS 767 for six traits. Likewise, among the entries, Co17018 was found superior to best checks for seven traits, followed by CoH 17262 for six traits and CoS 17234 and CoPb 17214 for five traits. The G X E interaction was found significant for all characters except for two traits namely, purity % at 10 months and purity % at 12 months. Based on the estimates of stability parameters as per Eberhart and Russell model, CoPb 17214 was observed as stable genotype for all traits except tillers/ha. Similarly, CoS 17236 and CoH17261 were found stable for fourteen traits except cane yield t/ha. Likewise, among the checks, Co 05011 was found stable for all traits except for cane yield, here this genotype was responsive in favourable environment. Check, CoS 767 was found stable for all traits except for germination percent. Based on the study the clone Co17018 was identified stable for cane yield and sucrose percent at 12 months, along with superiority over all the three checks. Hence, this genotype can be recommended for cultivation over different environments. While, two clones viz., CoS 17234 and Co 05011 were found responsive for cane yield in favourable environment, hence these can be recommended for cultivation under resource rich environment.ThesisItem Open Access Genetic analysis for yield, quality and nutritional traits in basmati rice oryza sativa l.(G.B. Pant University of Agriculture and Technology, Pantnagar, District Udham Singh Nagar, Uttarakhand. PIN - 263145, 2023-01) Reddy, Basu Sudhakar; Baskheti, D.C.The present investigation was carried out with the objective to assess genetic variability, genetic divergence and character association among 37 basmati and aromatic germplasm lines and to stimate combining ability and heterosis with respect to yield, its attribute, quality and nutritional traits. To study the nature of gene action for yield, its attributes and nutritional traits. Analysis of variance revealed highly significant differences among 37 basmati and aromatic lines for all the traits studied. Genotypic and phenotypic coefficients of variation were high for grain yield per plant, alkali spreading value and number of tillers per plant. High heritability coupled with moderate genetic advance was observed for traits like alkali spreading value, number of tillers per plant, length/breadth ratio, iron content, grain yield per plant and zinc content. Grain yield per plant was found to be positively and highly significant correlated with plant height, panicle length, 1000 grain weight, grain breadth, hulling % and milling %. Path coefficient analysis showed that the plant height, iron content, 1000 grain weight, grain length, and grain breadth contribute highly to grain yield per plant through direct effect. Thirty seven lines were grouped into seven clusters based on the D2 values. Maximum inter-cluster distance was between cluster IV (Ranbir Basmati, Tilak Chandhan, Basmati 564, Basmati 867) and VI (Hansraj, Pant Sugandh Dhan 17, Taraori Basmati) indicating that genotypes from these clusters were highly divergent meriting their consideration in selection of parents for hybridization. Ten lines and three testers were used to develop 45 F1’s crossed in Line × Tester fashion during kharif 2022. These F1’s were subjected to evaluation along with their parents including 1 check (Improved Pusa Basmati 1). Estimates of variance due to GCA and SCA and their ratio showed a predominance of non-additive gene effects in the expression of all the characters studied. Among the lines viz., asmati 386, Pant Sugandh Dhan 27, Taraori Basmati and among the testers Pant Basmati 2 was identified as good general combiner as they showed good general combining ability with most of the characters studied. The F1 Basmati 370 × Pusa 1509 was identified as the best specific combiner for grain yield per plant. The most promising heterotic crosses for grain yield per plant were Basmati 386 × Pusa 1121, Basmati 370 × Pusa 1509 and Basmati 386 × Pusa 1509 over the better parent and could be utilized commercially for exploitation of heterosis. Testing of Zromising hybrids across the location in diverse environment is suggested to establish their real potential. Generation mean analysis revealed that additive, dominance, additive × additive and dominance × dominance interaction effects were present along with duplicate dominant epistasis for grain yield and nutritional traits. Hence, selection may be delayed to later segregating enerations when the dominance and epistasis disappear and resorting to intermating of segregants followed by recurrent selection.ThesisItem Open Access Investigation on QTL mapping for BLSB resistance and protein content using wild relatives and introgression lines of maize(G. B. Pant University of Agriculture and Technology, Pantnagar, 2022-12) Varalakshmi S.; Singh, N. K.The main objectives of the investigation were to identify the genomic regions for BLSB resistance and other traits, to determine protein content and its association with SSR markers in teosinte-derived lines, maize and its wild relatives. The various experiments were conducted from 2019-20 to 2021-22for generation and field evaluation, and laboratory analysis of experimental materials. The characterization of teosinte derived 181 BC1F2 lines showed significant variation for all morphological traits and BLSB disease incidence. Of the 181 plants, 23, 53, 65 and 40 plants were grouped under resistance, moderately resistance, moderately susceptible and susceptible categories based on PDI score. The plants TM-1, TM-11, TM-12, TM-21, TM-28, TM-29, TM-54, TM-55, TM- 67, TM-77, TM-78, TM-85, TM-88, TM-94, TM-96, TM-101, TM-103, TM-113, TM-144, TM-152, TM-159, TM-161, and TM-167 were categorized under resistance group with PDI score of ≤ 33.33.The BC1F2 plants showed significant variability for days to anthesis, days to silking, anthesis - silking interval, flag leaf length, flag leaf width, flag leaf angle, plant height, node bearing primary cob and number of ears per plant. A total of 41QTLs were identified for BLSB resistance and 8 morphological traits based on single marker analysis. Two QTLs for BLSB resistance were mapped on chromosome 3 and 10 associated with markers umc2255 and bnlg1518 and having phenotypic variation of 3.79 and 2.22 per cent, respectively. Of the remaining 39 QTLs, 3 QTLs were for days to anthesis, 2 for days to silking, 5 for anthesis -silking interval, 4 for flag leaf length, 6 for flag leaf width, 4 for plant height, 6 for node bearing primary ear and 9 QTLs were for number of ears per plant. Using inclusive composite interval mapping method, a total of 12 QTLs were identified for BLSB resistance and 7 morphological traits and no QTL identified for node bearing primary ear trait. The QTLs qtlBLSB4.1 and qtlBLSB9.1 were detected on 4 and 9 chromosomes for BLSB resistance determining phenotypic variation of 2.08 and 4.63 per cent, respectively. The QTLs qtlDTA 8.1, qtlDTS7.1, qtlASI4.1, qtlFLL4.1, qtlFLL 4.2, qtlFLW8.1, qtlFLW10.1, qtlFLW10.2, qtlPH 4.1 and QtlEPP3.1 were mapped for various morphological traits across 3, 4, 7, 8 and 10 chromosomes. Highly significant differences for protein content were observed among 126 BC1F2:3 lines which varied from 9.53 to 16.49 per cent for MP51 and MP6 lines, respectively. Four lines (MP6, MP20, MP36, and MP97) had protein content in the range of 16.07- 16.49 per cent. All the BC1F2:3 lines possessed protein content higher than the maize parent CML-451 but lower than the teosinte. Analysis of protein content in 28 accessions of maize, its wild relatives indicates significant variations. Teosinte accessions possessed 2-3 times higher protein than maize lines, Z. mays subsp. mexicana, occupied top position with (26.29 per cent protein) of the 28 accessions. Five markers umc1294, umc1171, phi091, umc2182 and bnlg292 showed significant association with protein content. The investigation indicates great significance of teosinte for the diversification as well as improvement of maize for resistance to BLSB and kernel protein content. Teosinte may also be prospected for improvement of other traits in maize.
