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Open Access
Molecular diversity analysis and genetics of some morpho physiological and biochemical traits associated with moisture-stress tolerance in bread wheat (Triticum aestivum L.)
(CSK HPKV, Palampur, 2023-03-25) Anubhav, Shubhanshu; Rana, Vijay
The present investigation entitled ‘Molecular diversity analysis and genetics of some morpho-physiological and biochemical traits associated with moisture-stress-tolerance in bread wheat (Triticum aestivum L.)’ was conducted to identify morpho-physiological and biochemical traits associated with moisture-stress tolerance and analyze genetic diversity at morphological and molecular level. Experimental material for diversity studies comprised of 56 genetically diverse wheat genotypes; including some high yielding, drought tolerant lines, synthetics, local collections, recombinant inbred lines of a drought tolerant cultivar C 306. Experimental lines were evaluated for different traits in alpha-RBD design with three replications under irrigated (E1) and moisture-stress (E2) field conditions during Rabi 2017-18. A modified TTC analysis comprising 48 progenies; 16 lines and 3 testers was conducted under controlled irrigated (E1) and moisture-stress (E2) conditions during Rabi 2018-19. Significant genetic variability was observed for days to 50% flowering, flag leaf area (FLA), specific leaf area (SLA), specific leaf weight (SLW), relative water content (RWC), grain growth rate I (GGR-I), grain growth rate II (GGR-II), stem reserve mobilisation (SRM), tillers/ plant, grains/ spike, 1000-grain weight, biological yield/ plant, dry matter accumulation (DMA), grain yield/ plant, harvest index and proline content. High phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) along with high heritability and moderate genetic advance were recorded for proline content under E1 and E2. Grain yield/plant showed significant positive correlation with tillers/plant, 1000-grain weight, biological yield/plant, DMA and harvest index. Biological yield/ plant and harvest index appeared to be the best selection indices for increasing grain yield owing to high direct and indirect effects of these traits in path analysis. Under E1 first six principal components revealed 72.40 % and under E2 first five components explained 71.6 % of total variability. Variation for proline content contributed the maximum to the observed genetic divergence under both conditions. Congruence between morpho-phyiological and SSR data was observed under both the environments. Forty-six out of 56 test genotypes were common among molecular and morphological clusters under moisture-stress, whereas 39 genotypes were common under irrigated conditions. Genotypes SYN 105, IC 36737, HS 562, IC 594376 and VL 907 under irrigated conditions and genotypes viz. IC 322025, HS 490, VHC 6081, VHC 6127, SYN 103, VL 892, VHC 6413, C 306, VL 907, HPW 236 and SYN 117 under moisture-stress conditions were most diverse. STRUCTURE divided the experimental lines into two major populations. Modified TTC analysis was used to detect epistasis and estimates of additive and dominance components of variance for observed phenotypes, which indicated that mean squares due to epistasis were significant for all the traits except SLW and relative water content under irrigated conditions (E1) and FLA under (E2). Additive × Additive (i) type interactions were significant for GGR-I and tillers/ plant under E1 and E2 conditions while j+l type interactions were significant for all the traits except SLW and RWC under irrigated conditions (E1) and RWC under E2. The average degree of dominance (H/D)1/2 revealed similar gene action for 1000-grain weight and GGR-II under both E1 and E2. The comparison of estimates of genetic parameters using Line × Tester and Triple test cross indicated the role of overdominance in genetic control of traits namely, grains/spike, grain growth rate I and proline content under both the environments E1 and E2. Combining ability analysis revealed VHC 6413, HS 562, NIAW 1415, WH 1105 as good general combiners for FLA, GGR- II, grains/ spike, 1000-grain weight; Syntehtic 107 and NIAW 1415 for SRM; VHC 6081 and VHC 6127 for tillers/plant; HS 490,VHC 6127 and HS 507 for DMA; VHC 6127, HS 490, NIAW 1415 and NI 5439 for grain yield/plant; HS 562 and Synthetic 107 for harvest index; HS 507, Synthetic 107, Synthetic 112 and NIAW 1415 for proline content under both E1 and E2. HPW 89 x VL 907 recorded positive significant SCA effects for GGR- II; HPW 349 × VL 907 and HS 562 × HPW 368 for stem reserve mobilisation and VHC 6127 × HPW 368 for grains/spike and dry matter accumulation. These crosses were found promising and could be utilized for developing high yielding drought tolerant lines.
Open Access
Stability analysis for yield traits and association mapping of quality traits in oat (Avena sativa L.)
(CSK HPKV, Palampur, 2023-03-09) Sanadya, Sanjay Kumar; Sood, V.K.
Population growth, hunger and climate change are the major problems in the world. Therefore, a paradigm shift in agriculture is required to explore neglected and underutilized crop species that possess agronomic, nutritional and climate-resilient traits. Harnessing diverse oat genetic resources and development of stable cultivars are the sustainable solution to overcome these problems to some extent. Therefore, experiment was carried out to identify yield stable oat genotypes in organically and conventionally managed fields in the North Western Himalayas using AMMI and GGE biplot analysis and facilitate genetic dissection of quality traits employing ddRAD based GWAS approach. Ninety-six diverse oat genotypes were tested in five environments (year-production system combinations) using 12×8 alpha lattice design with three replications. Pooled ANOVA showed significant genotypic, environmental and GEI effects, suggesting GEI can be assessed in this population. Conventional system had higher yield over organic system across years. Environment and GEI were the major source of variation for all traits except dry matter percentage. Seed yield per plant showed positive significant association with biological yield per plant and harvest index whereas green fodder yield per plant exhibited positive significant association with number of leaves per plant and dry matter yield per plant. Genotypes SKO-190, UPO-119, OS-92, HJ-8, Choripatti and EC-523890 for seed yield per plant and HFO-878, HFO-502 and PLP-14 for green fodder yield per plant were found to be widely adapted. On the basis of polygon view of the GGE biplot, two mega-environments (MEs) were identified with winning genotypes ADG-96 and IG-03-205 in ME-1 and SKO-190, EC-605837, PO-1 and KUE in ME-2 for seed yield per plant whereas JPO-38, IG-03-205 and UPO-119 in ME-1 and SKO 28, RO-19, UPO-102 and JHO-99-2 in ME-2 for green fodder yield per plant. Genome-wide 35,262 SNP markers were used for the identification of genomic loci associated with five grain and forage quality traits phenotyped in different production systems across years. Distribution of SNPs ranging from 998 (chromosome 6D) to 2945 (chromosome 1A) with SNP density ranged from 1.94 per Mb to 5.60 per Mb window size. Population structure and kinship matrix analysis divided population into three groups with some admixtures indicating sufficient genetic variation. Total 31 significant marker-trait associations were detected across twenty one chromosomes for five quality traits. Out of which 6, 3, 9, 9 and 4 were identified for ADF, NDF, β-glucan content, crude protein content and crude protein yield per plant, respectively and explained 0.18 to 17.87% of total phenotypic variation. Twenty putative genes were found to be associated with QTLs linked with quality traits (100 Kb either side). Out of 31 QTLs, 10 QTLs explained more than 10% of total phenotypic variation thus these can be considered as major QTLs indicating a potential for using these markers in genomic assisted oat breeding programme.
Open Access
Genetic analysis of hybrid fertility and yield contributing traits in indica, japonica and wide compatibility genotypes of rice (Oryza sativa L.)
(CSK HPKV, Palampur, 2023-01-26) Kaur, Jeevanjot; Bhardwaj, Neelam
The present investigation entitled “Genetic analysis of hybrid fertility and yield contributing traits in indica, japonica and wide compatibility genotypes of rice (Oryza sativa L.)” was undertaken to get the information on nature and magnitude of gene action, combining ability and heterosis and thereby indentifying potential parents and cross combinations for yield, cold tolerance and disease restistance that could support further improvements of rice productivity using indica japonica hybrids. Eight parents viz; SKUA 500, SKUA 538, SKUA 536-2, HPR 3106, HPR 2143, Bhrigudhan, Naggardhan and Varundhan were crossed following Griffing’s method 2, model I in a half diallel fashion. Experimental material comprising of eight rice parents and twenty-eight hybrids were evaluated in RBD with three replications during kharif 2021 and 2022 at Rice and Wheat Research Centre, Malan and for the cold tolerance in rabi 2020-21at the experimental farm of the Department of Vegetable Science and Floriculture, CSK HPKV, Palampur. Under cold conditions spikelet fertility was observed in the order of japonica x japonica lines > japonica x wide compatible lines > indica x japonica lines > indica x wide compatible lines > indica x indica lines.The analysis of variance revealed significant differences among the genotypes for all the traits studied in all the environments, suggesting prevalence of wide range of genetic variability. Genotype x Environment (G × E) interaction was significant for most of the traits except days to 75% maturity, plant height, flag leaf length, flag leaf width, spikelet fertility, length:breadth ratio and amylose content indicating a definite role of environment on the performance of genotypes. SCA variances were higher than the GCA Variances and average degree of dominance was more than unity, thus showing preponderance of non-additive gene action for all the traits except amylose content. Based on GCA effects, SKUA 500, HPR 2143 and HPR 3106 were the most promising general combiners for grain yield/plant and most of the yield components. On the basis of SCA effect and heterosis, the cross combinations SKUA 500 x Naggardhan, SKUA 536-2 x HPR 2143, HPR 2143 x Bhrigudhan, SKUA 536-2 x Naggardhan and HPR 2143 x Varundhan were found best in pooled environment. Positive correlation of grains/panicle, grain length, and harvest index with grain yield/plant in parents and hybrids along with positive direct effect in path analysis revealed importance of these traits for selection of high yielding genotypes.
Open 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.
Open 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.
Open 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
Open Access
Genetic studies in Lolium-Festuca species and development of Lolium-Festuca hybrids
(palampur, 2023-02-23) Kumari, Anjali; Sood, V.K.
The present investigation entitled “Genetic studies in Lolium-Festuca species and development of Lolium-Festuca hybrids” was undertaken to assess genetic variation among four Lolium and 10 Festuca genotypes for various morphological and quality traits viz., plant height, leaf length, leaf width, tillers per plant, leaf area, green forage yield per plant, dry matter yield per plant, acid detergent fiber, neutral detergent fiber, crude protein content, and crude protein yield per plant, to develop intergeneric hybrids between Lolium and Festuca species and to identify good general combiners using polycross breeding in 10 fescue grass genotypes under field and polyhouse conditions at CSKHPKV, Palampur. A drought stress of 10 days was given to 45 days old plants to evaluate for various physiological traits such as root length, shoot length, root weight, shoot weight, root: shoot, leaf relative water content, chlorophyll a, b, a/b, total chlorophyll, proline content under well watered and drought stress conditions. On the basis of mean performance during drought stress conditions, among Festuca genotypes, Hima-3, Sel-63, Hima-15, Sel-88 and EC178182 were observed as drought tolerant genotypes whereas among Lolium genotypes, Palam ryegrass was observed as drought tolerant one. Pooled analysis of variance over cuts revealed significant differences among genotypes for all the traits studied viz., plant height, leaf length, leaf width, tillers per plant, leaf area, GFY, DMY, ADF, NDF, CP content and CPY. PCV and GCV were found to be high to moderate for most of the traits. High heritability coupled with high genetic advance, correlation studies and path analysis showed that selection for plant height, leaf length, tillers per plant, GFY and DMY would be effective. On the basis of polycross analysis, genotype Hima-3, Hima-1, Sel-71, Hima-15, EC-178182 and EC178184 were found to be the good general combiners for tillers per plant, GFY, DMY, ADF, NDF, CP%, CPY, leaf length, leaf width, plant height, leaf area and various physiological parameters that could further be used for the development of synthetics in fescue grass. Out of 12 crosses between four Lolium and three Festuca genotypes, only two intergeneric hybrids have been successfully developed which could further be used for analysis in Lolium- Festuca breeeding programmes.
Open 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.
Open Access
Combining ability and gene action studies for economic traits and disease resistance in linseed (Linum usitatissimum L.)
(palampur, 2019-05-02) Sran, Ranjeet Singh; Satish Paul
The present investigation entitled “Combining ability and gene action studies for economic traits and disease resistance in linseed (Linum usitatissimum L.)” was undertaken to get the information on nature and magnitude of gene action, combining ability and heterosis and thereby identifying potential parents and cross combinations for seed yield, fibre yield and associated traits under variable environments that could support further improvements of linseed productivity using appropriate breeding methodology. Eight linseed varieties viz., Surbhi, Bhagsu, Nagarkot, T-397, Himani, Baner, JRF-4 and JRF-1 were hybridized following Griffing’s Method 2, Model 1 in a half diallel fashion. Experimental materials comprising of eight linseed varieties and 28 F1 progenies were evaluated in RBD with three replications during the year 2016-17 and 2017-18 at Experimental Farm of the Department of Crop Improvement, CSK HPKV, Palampur. Various cross combinations were also examined to study the genetics of resistance to powdery mildew and rust in linseed at Palampur and research station SAREC Kangra, respectively during the year 2017-18. The analysis of variance revealed significant differences among the genotypes for all the traits studied during 2016-17, 2017- 18 and pooled over environments, suggesting prevalence of wide range of genetic variability. Variance due to environment in pooled analysis revealed significant differences for all the traits studied except seeds per capsule. Genotype × environment (G × E) interaction was significant for most of the traits except plant height and technical height indicated a definite role of environment on the performance of genotypes. Variances due to GCA, SCA and their interaction with environment were significant for most of the traits. For most of the traits, there was preponderance of non-additive gene action, under such situation diallel selective mating or biparental mating in early segregating generations followed by recurrent selection might be appropriate approach toward genetic improvement of these traits. Based on GCA, Nagarkot and Surbhi were found to be good general combiner for seed yield whereas, JRF-1 and JRF-4 for fibre yield. On the basis of SCA effect and heterosis, the cross combinations Surbhi × Baner, Himani × JRF-4 and Bhagsu × Nagarkot for seed yield and Nagarkot × Himani for fibre yield were found best in pooled over the environments. The segregation pattern of powdery mildew and rust disease indicated that resistance was governed by a single dominant gene in cross combination T-397 × Nagarkot.

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