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20224
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Subject: Genetics and Plant Breeding × End date: 2022 × Start date: 2022 × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    Genetic architecture of quality and yield components and molecular diversity assessment in blackgram (Vigna mungo L. Hepper)
    (Palampur, 2022-11-07) SOHARU, ALKA; Sood, V.K.
    The present investigation entitled "Genetic architecture of quality and yield components and molecular diversity assessment in blackgram (Vigna mungo L. Hepper)" was undertaken with the objectives to study diversity and quality profile of various land races prevalent in different regions of Himachal Pradesh and to study the nature and magnitude of gene effects for various quality and yield related traits and identification of desirable segregants. The materials comparising of 21 mash landraces along with three checks i.e. Him Mash-1, Palampur-93 and HPBU-111, were raised in a Randomized Block Design with two replications in two environmental (Berthin and Palampur) conditions and six inter-varietal crosses were raised in Compact Family Block Design at CSKHPKV Palampur. Analysis of variance revealed the presence of considerable amount of genetic variability for all the traits. On the basis of mean performance for different traits studied, genotypes viz., Sirmour-1, Kangra-1, Sirmour-2, Chamba-6 and Him Mash-1 were observed to have superior performance for traits like, number of branches per plant, seeds per pod, pods per plant, biological yield per plant and yield per plant. High estimates of PCV, GCV, heritability and genetic advance as % of mean observed for biological yield per plant and harvest index over the environments indicated the presence of additive gene action and sufficient variability for improvement through selection. Correlation and path coefficient studies revealed high positive direct effects of biological yield per plant, branches per plant and pods per plant on seed yield per plant at both the experimental sites. Hence, can be regarded as reliable selection factors for developing high-yielding cultivars. On the basis of DUS parameters, D 2 , PCA and molecular genetic diversity analysis, Sirmour-1, Sirmour-2, Chamba-2, Mandi-1, Kullu-3, Chamba-5, Kangra-3, Chamba-7, Bilaspur-1 and Chamba-8 were found to be diverse genotypes, which can be further utilized in urdbean breeding programme(s). For proximate composition genotypes Chamba-6, Kullu-4, Kinnaur-1, Chamba-3 and Kangra-2 were found superior as they had maximum amount of protein, fat, fiber, ash and carbohydrates, respectively. Among all the genotypes evaluated for cooking quality parameters, six genotypes namely Sirmour-2 for highest L:B ratio, Chamba-2 for high water uptake ratio, Chamba-7 for minimum amount of gruel solid loss, Chamba-8 and Chamba-1 for least cohesiveness and Him Mash-1 for least gumminess and chewiness after cooking were found promising. On the basis of yield and quality parameters genotypes Chamba-6, Sirmour-2 and Him Mash-1 were divulged as superior genotypes which can be firther validated by multilocation environment testing over the years. A simple scaling test employing generation mean analysis revealed that the digenic model (additive-dominance model) was inadequate for all of the traits, confirming the existence of non-allelic interactions for all of the crosses. Only duplicate type of epistasis was reported for three traits in Him Mash-1× Sirmour-2 and Palampur-93 × Kullu-4, four in Him Mash-1 × Kullu-4 and Palampur-93 × Chamba-8, two traits in Him Mash-1× Chamba-8 and Palampur-93 × Sirmour-2. Hence, bi-parental mating followed by selection in advanced generations is recommended.
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    ThesisItemOpen Access
    Molecular marker- assisted gene pyramiding of yellow rust resistance genes Yr5 and Yr10 into agronomically superior and potential cultivar HS 240 and a doubled haploid genotype DH 40
    (palampur, 2022-08-17) Singh, Kritika; Chaudhary, H.K.
    The research endeavour entitled “Molecular marker- assisted gene pyramiding of yellow rust resistance genes Yr5 and Yr10 into agronomically superior and potential cultivar HS 240 and a doubled haploid genotype DH 40” was executed in the Department of Genetics and Plant Breeding, CSK HPKV, Palampur during years 2018 to 2022 with the goal to incorporate genes conferring resistance to yellow rust in wheat into single genetic background and develop homozygous lines following doubled haploidy breeding technology. Marker- assisted backcrossing was employed to introgress Yr5 and Yr10 genes into genetic background of HS 240 and DH 40. Donor genotypes used for transfer of resistance genes were near isogenic lines developed using Avocet variety i.e., Avocet-Yr5 and Avocet-Yr10. Molecular markers STS7/8 and Xpsp 3000 were used for selection of Yr5 and Yr10 genes, respectively. Recovery of recurrent parent genome was quantified using polymorphic microsatellites. 448 SSR markers were used for screening of parental genotype, out of which 69 were polymorphic for HS 240 & Avocet-Yr5 and HS 240 & Avocet-Yr10 whereas, 68 markers for DH 40 & Avocet-Yr5 and DH 40 & Avocet-Yr10. For wide hybridization, intercrossed F1s were crossed with Imperata cylindrica to produce haploids which were further treated with colchicine for the development of homozygous doubled haploid plants. In BC1F1 and BC2F1 generation, plants having target genes were subjected to background selection. Background analysis revealed that the extent of recurrent parent genome recovery ranged from 63.07- 84.06 percent, 62.32- 83.33 percent, 60.29- 83.03 percent and 63.97- 83.82 percent for crosses HS 240*2/Avocet Yr5, HS 240*2/Avocet-Yr10, DH 40*2/Avocet-Yr5 and DH 40*2/Avocet-Yr10, respectively in BC1F1 generation. In second backcross, recovery percentage of recurrent parent genome ranged from 84.06- 92.03 percent, 84.78-92.03 percent, 84.56-91.91 percent and 86.76-93.38 percent in crosses HS 240*3/Avocet Yr5, HS 240*3/Avocet-Yr10, DH 40*3/Avocet-Yr5 and DH 40*3/Avocet-Yr10, respectively. Selected individuals having common recurrent parent were intercrossed to produce pyramided lines. The pyramided F1s were further subjected to development of doubled haploids. Various haploidy and doubled haploidy parameters like pseudoseed formation frequency (PFF), embryo formation frequency (EFF), haploid regeneration frequency (HRF), haploid formation frequency (HFF), percent survived plants (PSP) and doubled haploids formation frequency (DHFF) observed in cross (HS 240*3/Avocet-Yr5)//(HS 240*3/Avocet-Yr10) were 55.07 percent, 44.99 percent, 54.54 percent, 21.82 percent, 37.50 percent and 38.89 percent, respectively. While in cross (DH 40*3/Avocet-Yr5)//(DH40*3/Avocet-Yr10), 48.38 percent, 51.17 percent, 51.63 percent, 22.88 percent, 34.29 percent and 41.67 percent of PFF, EFF, HRF, HFF, PSP and DHFF were recorded on wide hybridization with I. cylindrica. Seven doubled haploid plants were developed from F1s of (HS 240*3/Avocet-Yr5)//(HS 240*3/Avocet-Yr10) and five for (DH 40*3/Avocet Yr5)// (DH40*3/Avocet-Yr10). The results of present investigation suggested that marker- assisted backcrossing and doubled haploidy breeding technology hasten the recovery of recurrent parent genome along with screening of target genes at early stage; and reducing number of generation & time for gene introgression in homozygous state thereby accelerating rapid line development.
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    ThesisItemOpen Access
    AMMI biplot analysis and phenotypic stability for seed yield and its component traits in linseed (Linum usitatissimum L.) under conventional and natural production systems
    (palampur, 2022-04-29) Thakur, Garima; Paul, Satish
    The present investigation entitled, “AMMI biplot analysis and phenotypic stability for seed yield and its component traits in linseed (Linum usitatissimum L.) under conventional and natural production systems” was undertaken during rabi 2019-20 and rabi 2020-21 to study the GE interactions for thirty linseed genotypes comprising of advanced breeding lines, elite cultivars and exotic lines across four different locations in Himachal Pradesh with varying altitudes viz., Palampur Bajaura, Kangra and Dhaulakuan with two production systems viz., conventional and Zero Budget Natural Farming (ZBNF) at each location. Therefore, the genotypes were evaluated over a total of sixteen environments (sites-years-production systems) for different yield and component traits. Stability analysis was carried out using Eberhart and Russell and AMMI model. Pooled analysis of variance as per both the models revealed significant differences among the genotypes, environments and GE interaction.As per Eberhart and Russell (1966) model the genotype identified as stable for seed yield was Surbhi. None of the genotypes were found stable for primary branches per plant, secondary branches per plant, capsules per plant, 1000 seed weight and oil content. Whereas, as per AMMI model stable genotypes were identified for all the traits. The most stable genotypes identified with respect to seed yield per plant were Giza-7, KL-278, Him Alsi-2, Janki and KL-279 and the most promising genotypes for oil content were Nagarkot, KL-257, KL-269, Him Alsi-1 and KL-279. Genotypes identified stable as per both the models were Him Alsi-2 for plant height, technical plant height and seeds per capsule, KL-285 and Nagarkot for plant height and Himani for harvest index. Genotypes showing specific adaptations were also identified. For site Palampur genotype Giza-8, for location Bajaura Him Palam Alsi-1(KL-241) and KL-311, for Kangra location KL-317 and Surbhi; for site Dhaulakuan genotypes KL-236, KL-315 and KL-284 showed specific adaptation under conventional system. However, under natural farming system for site Palampur genotypes Baner and KL-285, for site Bajaura genotype KL-284; genotypes KL-257 and KL-285 for location Kangra and Bhagsu, Nagrakot, Him Palam Alsi-2 (KL-263) and KL-284 for site Dhaulakuan showed specific adaptation. However, cross-overs were observed across years. Therefore, further evaluation for more years is recommended. Genotype KL-284 showed consistensy in its rank at location Bajaura under both production systems and hence, could be recommended for conventional as well as natural production systems with respect to site Bajaura. In terms of the environments, natural production system was observed as unfavourable environment for seed yield due to its consistent poor performance across years in comparison to the conventional system. It was also identified as poor discriminating environment. Genotypes KL-314 and Him Palam Alsi-2 (KL-263) were found to be resistant in all four locations for both powdery mildew and rust under epiphytotic conditions
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    ThesisItemOpen Access
    Molecular diversity analysis and biochemical profiling of Sri Lankan and Indian tea (Camellia sinensis (L.) O. Kuntze) genotypesMolecular diversity analysis and biochemical profiling of Sri Lankan and Indian tea (Camellia sinensis (L.) O. Kuntze) genotypes
    (palampur, 2022-06-27) Dananjaya, Kottawa Arachchige Jeevan; Chaudhary, Harinder Kumar
    The present investigation entitled, “Molecular diversity analysis and biochemical profiling of Sri Lankan and Indian tea (Camellia sinensis (L.) O. Kuntze) genotypes” was undertaken with the objectives of molecular and biochemical characterization of Sri Lankan and Indian tea germplasm and identification of potential genotypes to expedite its genetic improvement. Total of 171 tea genotypes comprising 94 Sri Lankan and 77 Indian genotypes were used to assess molecular diversity. Based on 16 morphological characters, first three principal components explained 57.61 % and 58.43 % of the total variability of Sri Lankan and Indian genotypes, respectively. Young shoot colour recorded the highest Shannon’s index (H’=1.14) and (H’=1.16) among morphological descriptors of Sri Lankan and Indian genotypes, respectively. Based on biochemical characterization, genotypes viz. PBGT35, PBGT48, PBGT53 and PBGT71 recorded low caffeine content. Total of 28 polymorphic SSRs i.e.10 unigenic SSRs and 18 functionally relevant SSR amplified 94 different alleles and were developed for molecular diversity and population structure analysis. Based on the SSR data of 171 accessions, all Sri Lankan genotypes were grouped in a single cluster whereas Indian genotypes were grouped in two distinct clusters through structure analysis and principle coordinate analysis (PCoA). Five core collections were developed by different methods. Based on the evaluation parameters, the core collection derived using Gower’s method was the most representative method of the initial collections of Sri Lanka and India. Among selected 21 Sri Lankan core genotypes, 11 accessions belong to introductions followed by 5 TRI developed cultivars and 5 estate selections. Among selected 18 Indian core genotypes, 11 accessions are of China types followed by 2 Assam types and 5 recommended cultivars.