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  • ThesisItemOpen Access
    Studies on alloplasmic and euplasmic heterosis in Brassica juncea L.
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-11) Rashmi; Ram Bhajan
    The present investigation was aimed to estimate heterosis and combining ability in Ogu alloplasmic hybrids as well as euplasmic hybrids, determine specific cyto-nuclear interactions and influence of ogu cytoplasm on hybrid performance. Experimental material consisted of 30 euplasmic hybrids generated by crossing 10 lines viz. PRL-2008-5, PBR-357, Maya, PRKS-28, Rohini, Sej-2, Vaibhav, EJ-22, PYR-2009-5 and PYR-2009-13 and three testers viz. IC-414317, IC-414322 and PR-2006- 14. Besides, same set of lines converted into ogu CMS background was used to develop 30 alloplasmic hybrids by crossing with three restorers (same set of testers carrying restorer gene). The parents, euplasmic and alloplasmic hybrids were evaluated in Compact Family Block Design with three replications during rabi 2016-17 at N.E.B.C.R.C., G.B. Pant University of Agriculture and Technology, Pantnagar. The data recorded on 13 characters was subjected to combining ability analysis (Kempthorne 1957), heterosis over mid parent as well as better parent (Hayes et al., 1955) and difference of mean values of two set of F1’s to determine extent of biological penalty. ANOVA revealed that mean squares due to families were significant for all characters while within family variance were found non-significant only for siliqua density. ANOVA for line × tester performed separately for both sets showed that treatment variance was significant for all characters in both the sets. Further partitioning of total variance into parents, crosses and parents vs crosses revealed that variance due to parents was significant for all characters except 50 % flowering and days to maturity in euplasmic set; and number of primary branches in alloplasmic set. Partitioning of variances due to crosses into lines, testers and line × tester in both sets showed significance mean squares for most of the characters. Mean squares due to testers were significant for number of primary branches, number of secondary branches, yield per plant and 1000 seed weight in alloplasmic set and for number of secondary branches and yield per plant in euplasmic set. For lines in euplasmic set, characters like plant height, length of main raceme, siliqua length and yield per plant showed significant differences while in alloplasmic set only yield per plant exhibited significant mean square. Variances due to line × tester interactions were significant for all characters in alloplasmic as well as in euplasmic set except siliqua length and number of seeds/siliqua in the latter. Based on desirable GCA effects, PBR-357, PYR-2009-5 and EJ-22 were identified as promising lines in euplasmic set while PBR-357A and PRL-2008-5A were high GCA lines in alloplasmic set for seed yield per plant. Among testers, IC-414317 and it’s A-line were found to be good general combiner in euplasmic and alloplasmic sets. The lines PBR-357, Maya, PR-20 in euplasmic and PBR-357A, PR-20A and RohiniA in alloplasmic set were identified as promising donors for oil content. Among testers IC-414322 was found to be good donor for oil content in both sets. Of these PBR-357, was found to have high GCA for seed yield per plant as well as oil content converged with key components. In euplasmic set, two crosses PBR-357 × PR-2006-14 & PR-20 × PR-2006-14 showed significant SCA for seed yield per plant and oil content. On the same analogy, three crosses MayaA × IC-414317, RohiniA × IC-414317 and EJ-22A × IC-414322 in alloplasmic set manifested significant SCA effects for these end products in desirable direction. The heterosis of high magnitude was manifested by large number of crosses for seed yield per plant in euplasmic as well as alloplasmic sets. Maya × IC-414317 manifested highest heterosis followed by Maya × IC-414322 and PBR-357 × PR-2006-14 in both of the sets while PBR-357 × IC-414322 and PBR-357 × PR-2006-14 for oil content were two promising combinations in both sets, respectively. The results revealed considerable amount of biological penalty which varied with cross combination and the characters. All crosses exhibited biological penalty for one or more characters under study. However, five alloplasmic cross combinations viz. PBR-357A × IC414317, PBR-357A × IC-414322, EJ-22A × IC-414322, PYR-2009-5A × IC414317 and PYR-2009-13A × PR-2006-14 performed better than corresponding euplasmic cross combinations for seed yield per plant indicating a positive cytoplasmic effect i.e. effect of cytoplasm was negated by restorer. Such combinations appear promising for commercial hybrid crop production. In the present study, influence of cyto-nuclear interaction was studied by comparing the estimates of GCA, SCA and manifestation of heterosis in euplasmic vis-à-vis in alloplasmic set of crosses. Comparison of GCA, SCA and heterosis estimates for different characters showed that it may or may not be affected by the cyto-nuclear interactions. There was complete change in the GCA status (Good to Poor or Poor to Good) of different lines for 3 or more characters. For example, PBR-357 exhibited changed GCA status for 9 characters, Maya for five characters; and PR-20 for only three characters i.e. siliquae on main raceme, number of secondary branches and siliqua length. GCA status nine lines were consistent in euplasmic as well as in alloplasmic sets for seed yield and six lines for plant height. Similarly visible influence of cyto-nuclear interaction was observed on SCA and heterosis in large number of crosses for different characters.
  • ThesisItemOpen Access
    Genotype × environment interaction for yield and related traits in some advance lines of pigeonpea (Cajanus cajan (L.) Millsp)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-12) Pal, Deepak; Verma, S.K.
  • ThesisItemOpen Access
    Genetic analysis of brown planthopper resistance and assessment of relative efficiency of different emasculation methods in rice (Oryza sativa L.)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-12) Rather, Shoukat Ahmad; Indra Deo
    Brown planthopper (BPH) is one of the destructive insect pests causing significant yield losses in rice. BPH causes direct damage to the rice plants by sucking the sap from phloem, causing hopper burn and transmitting viral diseases like grassy and ragged stunt viruses. Several resistant donors have been identified from time to time, but the new biotypes of the pest arise to defeat the extended use of resistance genes in a single variety. This necessitates the regular identification of new resistant donors along with their characterization at genetic and molecular level. Such characterization facilitates their easy and efficient utilization in crop improvement programmes. Keeping this in view, the present investigation was carried out at G.B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India to identify and genetically analyze the new BPH resistance sources using classical and molecular tools. In addition, some other objectives like characterization of advanced breeding lines of rice and assessment of relative efficiency of different emasculation methods were also undertaken. The phenotypic evaluation of advanced and stable lines of rice using standard seed box screening technique revealed that genotypes PHS 29, MRST 3 and RP 2068-18-3-5 were resistant to BPH whereas, all the advanced lines were susceptible except for UPR 3943-8-1-1, UPR 3947-23-2-2, UPR 3871-8-1-2-2, UPRI 2013-10, UPR 3906-18-2-1, UPR 3951-1-1-2-1, UPR 3957-5-2-2 and UPR 3960-2-1-1, which were moderately susceptible. The molecular analysis of mapping populations (F2:3) derived from TN 1 x PHS 29 and Pusa Basmati 1 x MRST 3 crosses revealed that putative SSR markers RM3355 and RM50 were associated with BPH resistance. Primer RM50 was also confirmed to be associated with the trait using a representative pool of advanced breeding and stable lines for molecular analysis. The inheritance studies carried out on the basis of goodness of fit of segregation ratios of BPH resistant and susceptible plants in F2 generation revealed that the resistance in PHS 29 and MRST 3 genotypes is conditioned by one and two recessive genes, respectively. The gene action of BPH resistance in PHS 29 was found to be additive in nature. Whereas, in MRST 3 genotype, it was found to be dominance in nature. As far as analysis of yield and yield contributing traits is concerned, genotypes reflected significant differences and superior grain yield per plant was recorded in genotypes UPR 3906-18-2- 1, UPR 3837-7-2-1-1, UPRI 2013-4 and UPR 3819-9-1-1-1 over the years. Among various emasculation methods, hand emasculation was found to be the most efficient with pooled mean efficiency of 84.05%. Suction method was identified as the second most efficient emasculation technique after hand emasculation with pooled mean efficiency of 75.74%. The results also indicated that emasculation efficiency is genotype- independent. Concluding the results of the present endeavour, the new resistance donors can be very useful in tackling BPH attacks on rice, especially in this part of the world. However, there is a need to conduct allelic tests of the identified resistant lines by crossing them with already characterized BPH resistant sources in order to know whether the identified BPH resistant sources in the investigation are different from previous sources. Furthermore, fine mapping analysis of these possibly new genes of resistance can be carried out using the linked markers identified during the present study.
  • ThesisItemOpen Access
    Studies on genetic diversity based on morphology, SSR markers and reproductive biological parameters in Bamboo species
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-11) Mohammed Talha; Tewari, Salil K.
    The present investigation entitled “Studies on Genetic Diversity Based on Morphology, SSR Markers and Reproductive Biological Parameters in Bamboo Species” was carried out during 2014-17 at G.B.P.U.A & T, Pantnagar, Uttarakhand. The research materials consisted of 10 species of bamboo for quantitative and qualitative parameter studies and 20 species for molecular diversity analysis based on rice SSR markers. The experiment was laid out in RBD with four replications. The data recorded on 21 quantitative characters were statistically analyzed through appropriate statistical procedures for means and variances, heritability, genetic advance and inter-character association. Genetic divergence was estimated using quantitative, qualitative parameters and rice SSR markers. Reproductive biology of Dendrocalamus giganteus, Bambusa bambos and Bambusa balcooa was studied. Seed characteristics, germination and seedling characteristics of Dendrocalamus giganteus were also investigated. Wide range of variation was observed for characters like bud length, culm diameter, leaf area, culm to culm distance, clump circumference, number of clums per clump and number of young shoots per clump. The culm sheath parameters varied immensely among the species and hence constitute important diagnostic feature for taxonomic characterization. High values of economic traits shows the commercial utility of these species for special requirement like thick culms (D. giganteus), total number of clums (D. hamiltonii) and total culm length (B. nutans). Other species like B. bamboos can be used for fodder purpose as it showed highest number of leaves per node and B. tulda produced maximum number of young shoots per year. High estimates of heritability with high genetic advance were recorded for culm to culm distance, culm diameter, culm height and leaf area which indicated that these characters are controlled by additive gene action and suggest the importance of employing direct selection for the improvement of such characters. The genotypic and phenotypic correlations were in same direction. The genotypic correlations were higher than phenotypic correlations for most of the character combinations which ensures the effectiveness of selection for these characters in order to maximize yield. D2-analysis showed maximum divergence between the species of cluster II and cluster III indicating these to be genetically different. Character inter-nodal length contributed maximum towards divergence. Hierarchical clustering of ten accessions on the basis of quantitative parameters, 30 qualitative characters and SSR markers revealed genetic dissimilarity between bamboo species. Resolving power of qualitative characters was better in species discrimination than quantitative characters. On the other hand, SSR based dendrogram was more accurate than the above two approaches in species delineation with exception in only one cluster. This study reveals superiority of molecular based phylogenetic studies in bamboos over traditional methods centred on morphological traits. Present investigation shows that rice SSR markers are transferable to bamboo species which can be used to distinguish different genotypes including albino seedlings, flowering and non-flowering clumps within species. Isolated flowering of two D. giganteus clumps was preceded by death of culms though reversion to vegetative state was also reported. B. bambos flowered gregariously followed by heavy seed set and dried completely. Partial flowering with no seed set was reported in B. balcooa. In all the three species flowering occurred only in some of the populations indicating that there are different flowering cohorts for the same species. Observations on floral morphology of all three species showed differences in the reproductive structures. Seeds of D. giganteus showed variation for various seed characters. Low germination percentage and drastic reduction in seed viability on short term storage demands further research in defining optimum storage conditions for seeds to promote its use as propagating material and fresh regeneration of bamboo plantations. Albino seedlings were frequently detected in D. giganteus which can be used in further genetic analysis on albinism and can be useful as marker in population genetic studies.
  • ThesisItemOpen Access
    Studies on seed longevity with packaging materials, genetic variability and molecular diversity of soybean (Glycine max (L.) Merrill)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-08) Bhakuni, Vandana; Shukla, P.S.
    The present study was taken up to study seed longevity of soybean seeds stored in different packaging materials, effect of priming on seed quality parameters, analysis of genetic variability and molecular marker diversity analysis using sixteen different SSR primers for effective selection and improvement of crop plant. For field experiment 12 varieties were planted in randomized complete block design with three replications during Kharif 2013 and 2014 at N. E. Borlaug Crop Research Centre. All the lab experiments were conducted in the seed testing laboratory at Breeder Seed Production Centre and department of Genetics and Plant Breeding, G. B. Pant University of Agriculture and Technology, Pantnagar. The analysis of variance for different field characters indicated highly significant differences among varieties for all the ten characters studied in both the years. This indicated that the experimental material contained sufficient amount of variability. In both the years estimated values of phenotypic coefficient of variation were higher than genotypic coefficient of variation for all the characters studied. Plant height exhibited highest phenotypic coefficient of variation followed by yield per plant in both the years. Most of the traits included in this investigation were considered highly heritable as they have shown to be associated with moderate to high estimate of broad sense heritability. In 2013 as well as 2014 highest heritability in broad sense was obtained for plant height i.e., 97 and 98% respectively. The expected genetic advance in 2013 varied between 0.26% for number of seeds per pod to 35.61% for plant height. Similarly, in 2014 expected genetic advance varied from 0.09% (number of seeds per pod) to 37.44% (plant height). High heritability coupled with high genetic advance was observed for plant height and number of pods per plant in both the years. Analysis of variance revealed that storage periods, packaging materials and the variety to be stored had a significant effect on all the thirteen seed quality parameters studied in both the years. During both the years it was observed that there was a decrease in germination per cent and vigour with time. Highest values for germination and vigour were observed at P1 (after 45 days of storage) while it decreased at P3 (after 135 days of storage). The present study revealed that after 135 days of storage varieties like PS 1024, PK 327, Bhatt and Bragg had germination per cent below 70% while all the remaining varieties, Ankur, PS 1225, PK 472, PS 1092, Kalitur, JS 335, PS 1347 and PK 1029 maintained their germination upto 70%. With respect to containers, it is apparent from the results that tin container maintained seed quality the most; followed by jute bag, paper bag and cotton bag. Seeds stored in earthen pot lost their vigour and quality the most. All the varieties exhibited decrease in oil per cent with time while the effect of packaging material was not significant on oil per cent. Mean value for oil content reduced from 15.72 (after 60 days of storage) to 12.99% (after 120 days of storage). It was observed that packaging material, priming agents and varieties to be treated had a significant effect on seed quality parameters. Highest germination was recorded in seeds primed with CaCl2.2H2O (62.51), followed by GA3 (61.83) and nSiO2 (57.18%) while unprimed seeds had the lowest germination per cent (44.12%). Highest germination per cent was recorded for seeds stored in jute bag when primed with GA3 (70.75) which was at par with the seeds stored in tin container primed with CaCl2.2H2O (69.44%). The assessing of SSR diversity of twenty soybean genotypes revealed that the Jaccard’s similarity coefficient estimates between pair of different varieties varied from 0.59 [between Kalitur and JS 335, Ankur and Bhatt] to 0.92 [between PK 472 and Ankur]. The average number of alleles per primer was 4.125, while percentage of all bands that showed polymorphism was 100%. The UPGMA ordered the population of twelve varieties into two main groups namely Group A and Group B and five clusters. Based on dendrogram PS 1347 and Ankur were found to be most distant.
  • ThesisItemOpen Access
    Genetic analysis of quantitative traits in aromatic rice ( Oryza sativa L.)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Singh, Mithilesh Kumar; Singh, Surendra
    The present investigation was conducted with 28 F1 hybrids, 8 parents and one check variety (Improved Pusa Basmati-1) during kharif, 2016 at Norman E. Borlaug Crop Research Centre, Pantnagar to study the combining abilities, gene action and their genetic parameters for yield and quality traits. Analysis of variance revealed significant differences among genotypes for all the traits indicating the presence of ample amount of variability. The magnitude of the phenotypic coefficient of variation (PCV) was higher than the genotypic coefficient of variation (GCV) for all the traits. The highest estimates of broad sense heritability were observed for plant height. High heritability estimates coupled with high genetic advance as percent of mean was recorded for alkali digestion value and number of panicles per plant. The standard heterosis for grain yield per plant varied from 17.10% (Pusa Basmati-1×Pusa Sugandh-4) to 193.87% (Pusa Sugandh-6×PSD-15). The top three promising hybrids for grain yield per plant were Pusa Sugandh-6×PSD-15, Pusa Basmati-1×PSD-15 and Pusa Sugandh-6×Basmati-370. For superfine aromatic rice quality traits; top three promising hybrids for kernel length were PSD-15×Pant Basmati-1, Pusa Sugandh-6×Tarori Basmati-1 and Pusa Basmati-1×Tarori Basmati-1 whereas, Pusa Sugandh-6×Tarori Basmati-1, PSD-15×Pant Basmati-1 and Pusa Basmati-1×Tarori Basmati-1 were top three hybrids for kernel length/breadth ratio. Top three promising hybrids, Pusa Sugandh-4×Tarori Basmati1, Pusa Sugandh-4×Pant Basmati-1 and Basmati-370×Tarori Basmati-1 expressed highest estimates of positive heterosis over standard check for kernel elongation ratio. Combining ability analysis revealed that the GCA and SCA variance were significant for all the traits indicating importance of both additive and nonadditive genetic variance in trait expression. The GCA effects of the parents indicated Pusa Basmati-1 as best general combiner for 13 traits followed by Pusa Sugandh-6 for 11 traits. The top 3 specific combiners for grain yield/plant were Pusa Sugandh-6×PSD-15, Pusa Basmati-1×PSD-15 and Pusa Sugandh4×Basmati-370. The hybrids Pusa Sugandh-6×Tarori Basmati-1, PSD-15×Pant Basmati-1 and Pusa Basmati1×Tarori Basmati-1 were top three per se performer for super fine aroma rice quality traits like kernel length, kernel length/breadth ratio and kernel elongation ratio, among which the cross Pusa Sugandh-6×Tarori Basmati-1 also had high SCA effect for all these three traits. The graphical analysis revealed partial dominance for days to 50% flowering while overdominance of rest of the traits. A significant deviation of regression line from unity indicated the presence of epistasis to be involved in expression of all the traits except test weight and number of filled grains per panicle. Array of parental points scattered in Wr-Vr graph for most of the traits indicated that the parents were genetically diverse. The estimates of genetic component of variance indicated preponderance of non-additive gene action for some traits while preponderance of both additive as well as non additive gene action for rest of the traits. The proportion of dominant to recessive genes was not in equal proportion for most of traits in parents. The genes showing positive and negative were asymmetrically distributed among parents for all the traits. Grain yield per plant showed positive and significant correlation with plant height, flag leaf length, panicle length, number of panicles per plant, number of filled grains per panicle, spikelet fertility and test at both, genotypic and phenotypic level. Most of the genotypes were strong in aroma as suggested by aroma index.
  • ThesisItemOpen Access
    Genetic studies on agro-morphology, quality traits, blast resistance and QTL detection for iron and zinc contents in rice (Oryza sativa L.)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Harsha; Indra Deo
    The present investigation entitled “Genetic studies on agro-morphology, quality traits, blast resistance and QTL detection for Iron and Zinc contents in rice (Oryza sativa L.)” was carried out during kharif, 2014-15 and 2015-16 at G.B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand and V.P.K.A.S. Almora, Hawalbag, during kharif, 2015-16. The research material consisted of twenty-nine lines of rice genotypes, F2 segregating population of cross Basmati-370 and Taraori Basmati and two cross were taken for inheritance study of rice leaf blast at field and molecular level. Analysis of variance explained highly significant differences among the rice genotypes for all the ten yield and yield component traits. High heritability coupled with high genetic advance and high to moderate PCV and GCV were observed for number of effective tillers per plant, flag leaf area, grain yield per plant and test weight. At phenotypic and genotypic level grain yield per plant showed the significant positive correlation with number of effective tillers per plant and test weight. The path coefficient analysis revealed at the phenotypic level, number of effective tillers per plant had a highest positive direct effect on grain yield per plant followed by flag leaf area, days to maturity, panicle length and leaf length. Analysis of variance exhibited highly significant and usable variability among the genotypes for all the quality parameters. High to moderate values of PCV and GCV, high heritability pair with high genetic advance were observed for most of the characters, i.e. cooked kernel length, kernel length breadth ratio, cooked kernel length breadth ratio, milling recovery (%) and head rice recovery (%). Dunken Multiple Range Test (DMRT) revealed the presence of significant difference among the rice genotypes for micronutrient concentrations. In brown rice iron concentration ranged from 23.13 - 53.38 mg kg-1 whereas, zinc concentration ranged from 23.27 - 54.49 mg kg-1. In white rice iron concentration ranged from 9.04 - 25.11 mg kg-1 whereas, zinc concentration varied from 9.04-25.25 mg kg-1. Per cent loss for the iron and zinc concentration in rice grain ranged from 23.67 - 80.43 and 19.35 - 71.66 per cent respectively. The loss in micronutrient content after milling changed with the grain type as long slender grain type showed more percent loss for micronutrient the short bold grain type. SSR markers were used to estimate molecular diversity among the genotypes for the micronutrients content. Using eighteen SSR markers 53 alleles were detected among the rice genotypes range of 80 to 1000 bp with five rare alleles. PIC value ranged from RM 340 (0.339) to OsNRAMP 7 (0.803) similarity coefficients between the pair of genotypes varied from maximum of 0.67 to a minimum of 0.04. Based on Jaccards similarity coefficients, UPGMA ordered the twenty-nine rice genotypes in to four clusters. Cluster III and IV had a similarity coefficient of 0.31 and genotypes found in those clusters were show diversity. In F2 population, Basmati-370 and Taraori Basmati were taken as parents and showed a range of grain iron and zinc content in brown rice 34.22 ppm, 43.31 ppm and 53.38 ppm, 54.49 ppm, respectively. The F2 population was varied for iron content from 9.56 to 80.73 ppm whereas, for zinc content from 5.37 to 53.96 ppm. Seven polymorphic primers subjected to single marker analysis and discovered 14 QTLs associated with morphological traits. RM 21 marker located on chromosome no. 11, explained the maximum phenotypic variation for zinc content which was 17.87 percent and for iron content it showed 6.02 percent phenotypic variation. Inheritance study for rice leaf blast the cross PB-1 X IR-64 only show the genotypic as well as phenotypic ratio in 3:1 for susceptible to resistant reaction.
  • ThesisItemOpen Access
    Parental diversity, heterosis and gene action for yield and yield contributing traits in maize (Zea mays L.)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Tripathi, Anurag; Verma, S.S.
    The present investigation was carried out with half diallel mating design involving ten parents under two different plant densities (high plant density and optimum plant density) in kharif 2015, at N. E. Borlaug Crop Research Center, Pantnagar. Experimental material consisted of 10 parents, their 45 F1s and two checks, PSM1 and Vivek 43 were evaluated under RBD with three replications in two different plant density environment. Observations on grain yield and yield attributing traits were recorded and analyzed with analysis of variance. The analysis of variance for combining ability over two different plant density environments (OPD and HPD) indicated that mean sum of squares due to GCA was significant for all the characters in OPD and HPD environments. However, the mean sum squares due to SCA was found significant for all the characters in both the environments, except for ear diameter in OPD environment. This suggested that both additive and non additive gene action responsible for expression of traits. For all the traits ratio of variance GCA to SCA was lesser than unity that indicate the presence of non additive gene action. The GCA effects of parents in OPD, P1 for days to 50% tasselling, days to 50 % silking, ear height and in HPD P2 and P8 to be best general combiner for five traits as P2 for days to 50% tasselling, days to 50% silking, ear diameter, 100 kernel weight, grain yield and P8 for ear diameter, no of kernel rows per ear, grain yield. The promising cross combination for grain yield P1 X P10. For grain yield some promising crosses showing superiority over both mid parent and better parent. Crosses, P1 X P10, P4 X P9, P4 X P10, P5 X P7, P5 X P6, P2 X P9, P3 X P6, P3 X P8,, P4 X P10 showed high estimates of heterosis for grain yield. In the present investigation, the estimates of phenotypic coefficient of variation (PCV) were higher than that of genotypic coefficient of variation (GCV) and environmental coefficient of variation (ECV) for all the characters in both the environments. High level of broad sense heritability (h2) estimates (%) were observed for number of kernel rows/ear followed by days to 50% tasselling, days to 50% silking and plant height whereas moderate heritability estimates were recorded for anthesis- silking interval, ear length, grain yield ear height and ear length showed heritability in HPD. Molecular polymorphism indicated that average number of alleles were 7.24 per marker with a range from 4 to 10 alleles, in which, marker, K2T2 was least informative and marker, K1T5 was highest informative. The most similar parental lines were P2 and P3 (0.80) while least similar parents were P1 and P3 (0.13). Cluster diagram based on Jaccard’s similarity coefficients and UPGMA algorithm showed that major cluster B was having the nine parents while cluster A had only one parent. Clustering of parental lines indicate the presence of enough genetic diversity among the parents.
  • ThesisItemOpen Access
    Study of variability induced through mutagenesis in chickpea (Cicer arietinum L.)
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2015-07) Dinkar, Vishal; Arora, Anju
    Chickpea (Cicer arietinum L.) is a self-pollinated diploid (2n=16) annual grain legume that belongs to the family Fabaceae. Due to self-pollinated nature of crop and small flower size, conventional methods of plant breeding have a limited scope in improvement of chickpea. Mutation breeding is an effective tool for a plant breeder to generate variability especially in crops like chickpea with narrow genetic base. The present investigation was carried out in three desi chickpea varieties - Pant Gram 114, Pant Gram 186 and Pant Gram 3 released from Pantnagar. The seeds were mutagenized with gamma ray (300 Gy & 400 Gy doses), ethyl-methane sulphonate (EMS 0.5%) and their combination treatments (300 Gy gamma ray + 0.5% EMS & 400 Gy gamma ray + 0.5% EMS). M1 generation showed gradual decrease in germination with increase in the mutagen strength in all the three varieties which indicated that combination treatments caused more biological damage than individual mutagen treatment. Morphological mutants such as chlorophyll mutants, high anthocyanin pigmented type, narrow leaves with entire margin types, variegated leaf type, tall type and fasciated stem type were observed. In M2 generation, chlorophyll mutations were most frequent in Pant Gram 186 followed by Pant Gram 3 and Pant Gram 114. The interaction effects were found significant with significant effects of varieties for characters viz., plant height, days to first flower, height of first pod bearing node from base, days to maturity, number of secondary branches /plant, leaf length and yield/plant. This indicated that varietal differences were significantly affected by different mutagenic treatments. In M2 generation, individual plant progenies showed segregation for different characters. Among all the three varieties, PG3 M1 plant progenies were found more frequently segregating i.e., 11%, followed by PG186 (9%) and PG114 (7%). In all the three varieties, frequency of viable mutants increased with increase in dose of gamma ray, whereas EMS alone gave comparatively higher frequency than combined treatments. Viable mutants were more frequent in PG3 variety i.e., 1.04% followed by PG186 (0.69%) and PG114 (0.54%).In PG114, significant change of mean from control was observed only for plant height, days to maturity, internode length, cumulative length of petiole and rachis, leaf length, leaf width, pod length. In PG186, for most of the characters change in mean was significant except for plant height, no. of secondary branches/plant, cumulative length of petiole and rachis, average no. of seeds/pod and yield/plant. In PG3, mean for most of the characters decreased except days to flowering and no. of secondary branches/plant. In all three varieties, variance for yield and most of the yield contributing characters significantly increased in all kind of mutagenic treatments except for plant height and height of first pod bearing node (in PG114), average no. of seeds/pod (in PG186) and cumulative length of petiole and rachis; average no. of seeds/pod and yield/plant (in PG3). In general, combined treatments 300 Gy + 0.5% EMS and 400 Gy + 0.5% EMS were observed to be most effective in inducing variability (high variance and CV) for most of the characters under study. In a nutshell, it can be concluded that combined treatments 300 Gy + 0.5% EMS and 400 Gy + 0.5% EMS were observed to be most effective in inducing variability (high variance and CV) for most of the characters under study. Different viable mutants identified in individual plant progeny rows in M2 generation like fasciated stem type, long internode type, leaf mutants, growth habit mutants like primary branching mutant, secondary branching mutant, compact type, tall types, bushy types and erect types, late maturity type, flowering mutant, and double mutants (i.e., light green plant colour type, tall + erect types, tall + early flowering type and early flowering + leaf mutant type) can be used as genetic stocks for useful traits and can be utilized in future crop improvement programs.