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ThesisItem Open Access HETEROSIS, COMBINING ABILITY AND GENETIC ARCHITECTURE IN COWPEA {Vigna unguiculata (L.) Walp.]2036(JAU, JUNAGADH, 2015-07) BABARIYA CHIRAC ASHOKBHAI; L. K. DHADUKAn experiment was conducted in a randomized block design with three replications at Instructional Farm, Junagadh Agricultural University, Junagadh during summer, 2014 with a view to estimate heterosis, inbreeding depression, combining ability and nature of gene action involved in the inheritance of seed yield and its components traits in cowpea [Vigna unguiculata (L.) Walp.]. For this purpose using diallel mating design (excluding reciprocals) involving ten different genotypes in Fj and F2 generations. The analysis of variance revealed that significant difference among the parents except for harvest index in both Fi's and Fa's generations indicating substantial amount of genetic variability among the parents for the characters studied. For parents versus Fi's were also found significant for seed yield and its components traits, except for days to maturity and protein content. This indicated substantial amount of heterosis in cross combinations and Fi's vs Fa's revealed that the Ffs differed significantly from their Fa's for all the characters, except for number of pods per cluster and pod length suggesting presence of considerable amount of inbreeding depression in Fa generation. The cross combination GC 2 x GC 5 exhibited highest significant and positive heterobeltiosis and high standard heterosis along with low magnitude of inbreeding depression followed by GC 4 x Pant Lobia 2, RC 101 x GC 1, KM 5 x GC 1, IT 38956 1 x KM 5 and IT 38956 1 x GC 5 indicated that these crosses may be exploited for development of high yielding stable lines. The cross Pusa Phalguni x GC 2 exhibited high significant and positive heterobeltiosis and standard heterosis along with high magnitude of inbreeding depression followed by GC 2 x Pant Lobia 1, GC 4 x Pant Lobia 1, Pusa Phalguni x Pant Lobia 1, Pusa Phalguni x Pant Lobia 2, RC 101 x Pant Lobia 2, RC 101 x Pant Lobia 1 and GC 1 x GC 4 suggested that these crosses could be suitable to get better transgressive segregants in segregating generations. The estimate of variance components due to general and specific combining ability indicated that non-additive gene action played an important role in the expression of all the characters. Estimates of gca effects indicated that the parents, IT 38956 1 and RC 101 were observed to be the best general combiners for seed yield per plant along with branches per plant and number of pods per plant in both generations. Likewise other parents were also good general combiner for particular yield attributing traits.ThesisItem Open Access GENETICS OF QUANTITATIVE TRAITS IN BREAD WHEAT (Triticum aestivum L.) OVER ENVIRONMENTS 2529(JAU,JUNAGADH, 2018-03) SHAH SIDDHI HITENDRAKUMAR; Dr. J. B. PATELThe present investigation entitled “Genetics of quantitative traits in bread wheat (Triticum aestivum L.) over environments” was carried out with a view to estimate heterosis, combining ability and gene action, genetic components of variance, genotype x environment interaction and stability parameters for grain yield per plant and 13 different quantitative traits in bread wheat. The experimental materials comprised of nine parents (NW 5013, DBW 90, PHSC 5, GW 2010-287, BW 5872, QLD 65, QLD 46, RAJ 4238 and GW 496), their thirty-six F1 hybrids and one standard check variety GW 366 were evaluated in three different environments [Early (25th October), timely (15th November) and late sowing (5th December)] designated as environment I (E1), environment II (E2) and environment III (E3), respectively, in randomized block design with three replications during rabi 2016-17 at Sagadividi Farm, Department of Seed Science and Technology, College of Agriculture, Junagadh Agricultural University, Junagadh. Five competitive plants per genotype in each replication in each environment were selected randomly for recording observations on different characters viz., plant height (cm), number of effective tillers per plant, length of main spike (cm), peduncle length of main spike (cm), number of spikelets per main spike, number of grains per main spike, grain weight per main spike (g), 1000 grain weight (g), grain yield per plant (g), biological yield per plant (g) and harvest index (%), while observations on days to heading, grain filling period and days to maturity were recorded on plot basis. The data were analyzed for heterosis and combining ability (Method-II, Model-I of Griffing, 1956), while the genetic components of variation were estimated according to Hayman (1954) and G x E interactions and stability parameters were calculated following the model of Eberhart and Russell (1966). The analysis of variance for genotypes, parents and hybrids indicated the existence of considerable amount of genetic variability amongst genotypes, parents and hybrids for seed yield per plant and most of the characters under study. The comparison of parents vs. hybrids across the environments, in general, revealed the existence of heterosis. The interaction of genotypes with the environments indicates the non-linear response of the genotypes to the change in the environment. No specific consistency was observed with regards to heterosis for grain yield and yield component in different crosses. On pooled basis, four hybrids over better parent and one hybrid over standard check variety exhibited significant and positive heterosis. NW 5013 × BW 5872 in E1, PHSC 5 × GW 2010-287, DBW 90 × BW 5872 and NW 5013 × QLD 65 in E2, NW 5013 × QLD 65, DBW 90 × GW 2010-287, PHSC 5 × GW 2010-287 and DBW 90 × BW 5872 in E3 and PHSC 5 × GW 2010-287 in pooled results were the best significant and positive cross combinations with respect to standard heterosis for grain yield per plant. Abstract ii The significant difference of GCA and SCA indicated that both additive and non-additive gene effects played an important role in the genetic control of the traits studied. The ratio of σ2gca / σ2sca was lesser than unity indicates the preponderance of non-additive gene action for all the characters studied in individual environments as well as across the environments. On pooled basis, the parents PHSC 5, QLD 46 and Raj 4238 were found to be good general combiners for grain yield per plant and possessed high concentration of favourable genes as indicated by significant and positive GCA effects for these parents. Considering the overall performance of hybrids across the environments for grain yield per plant, eight hybrids viz., PHSC 5 × GW 2010-287, DBW 90 × GW 2010-287, DBW 90 × BW 5872, Raj 4238 × GW 496, DBW 90 × GW 496, NW 5013 × DBW 90, NW 5013 × QLD 65 and GW 2010-287 × QLD 65 manifested significant positive sca effects. The three best specific crosses involved good x poor and average x poor general combiners. Relative magnitude of dominance component was found to be higher than additive component for most of the traits in all three environments, indicates that studied characters were mostly under the control of dominance variance. The average degree of dominance (H1/D)1/2 indicated over dominance type of gene action in individual environments for all the traits studied except in E2 for number of effective tillers per plant. The distribution of genes with positive and negative effects (H2/4H1) in the parents was observed nearly symmetrical for grain yield per plant and all the characters studied. The estimates of KD/KR ratio was more than unity indicated the excess of dominant alleles in parents for all the characters studied except for number of effective tillers per plant in E1, for peduncle length of main spike in E1 and E2, for number of spikelets per main spike in all three environments, and for number of grains per spike and biological yield per plant in E2. The ratio of h2/H2 indicated that there was one group of genes responsible for controlling all the traits studied. The low to moderate estimates of narrow sense heritability was depicted for most of the traits in individual environments indicated that the characters studied were much influenced by the environments. Two parents (NW 5013 and QLD 46) and twelve hybrids (PHSC 5 × GW 2010-287, DBW 90 × GW 2010-287, DBW 90 × BW 5872, NW 5013 × QLD 65, BW 5872 × QLD 65, GW 2010-287 × BW 5872, Raj 4238 × GW 496, QLD 65 × QLD 46, GW 2010-287 × QLD 46, BW 5872 × QLD 46, BW 5872 × Raj 4238 and GW 2010-287 × Raj 4238) expressed their stability across the environments for grain yield per plant due to their high per se for grain yield per plant, non-significant regression coefficient (bi) and deviation from linear regression (S2di). On the basis of per se performance, stability and general combining ability estimates of the parents for grain yield and its components in individual environments as well as across the environments, parents PHSC 5, QLD 46, NW 5013 and Raj 4238 may be used in heterosis breeding for isolating desirable types in bread wheat. On the basis of per se performance, stability, heterotic response, specific combining ability estimates and gene action involved in the expression of grain yield and its components in individual environments as well as across the environments, cross combination PHSC 5 × GW 2010-287 appeared to be the most suitable for exploitation in practical plant breeding programme in wheat, as this hybrid across the environments ranked first with respect to grain yield per plant (18.88 g) with significant standards heterosis (18.00 %) and significant sca effects for grain yield per plant, and was found to be stable for grain yield per plant, grain filling period, length of main spike, peduncle length of main spike, number of spikelets per main spike and harvest index. Therefore, this cross could be exploited for the improvement of grain yield and specific yield contributing characters in wheat.ThesisItem Open Access “IDENTIFICATION OF SELECTION CRITERIA IN F4 AND F5 GENERATIONS IN MUNGBEAN [Vigna radiata (L.) R. Wilczek]” 2448(JAU,JUNAGADH, 2017-10) MalakiyaNarseebhaiJerambhai; Dr. B. A. MonparaKey words: Genetic variability,heritability, genetic advance, correlation, path analysis, selection indices. The present investigation was carried out in Randomized Block Design with three replications at Instructional Farm, Department of Agronomy, College of Agriculture, JAU, Junagadh during Summer and kharif 2016. A set of 20 F4 and its subsequent F5 populations along with 8 parents of mungbean were utilized to estimate genetic variability, character association, path analysis and selection indices. The segregating F4 generation was obtained from Research Scientist (Chickpea), Pulses Research Station,Junagadh Agricultural University, Junagadh. The observations were recorded on 20 randomly selected plants from each population per replication and their mean values were used separately for statistical analysis. The characters considered under study were days to flowering, days to maturity, plant height, number of branches per plant, number of clusters per plant, number of pods per plant, pod length, number of seeds per pod, seed yield per plant and 100-seed weight. The analysis of variance revealed highly significant difference among the segregating populations for all the ten characters,suggesting sufficient amount of variability among the F4 and its subsequent F5 segregating material. In the present experimental material, wide range of variation was observed for number of branches per plant, number of clusters per plant, seed yield per plant and number of pods per plantin case of F4. While, in case of F5 it was observed for number of branches per plant, seed yield per plant, number of clusters per plant, number of pods per plantand plant height. In F4, the high value of GCV was observed for number of branches per plant and number of clusters per plant. The moderate value for GCV was observed for seed yield per plant, number of pods per plant and number of seeds per pod.While in case of F5, highest value for GCV was observed for number of branches per plant and seed yield per plant. It was observed moderate for number of clusters per plant, plant height and number of pods per plant. In F4, the high heritability (in broad sense) values were observed for days to flowering followed by number of clusters per plant, number of branches per plant, number of seeds per pod and 100-seed weight. While in case of F5, the high values for heritability was recorded for plant height followed by number of branches per plant, number of clusters per plant, number of seeds per pod and seed yield per plant. In F4, the genetic advance at 5% selection (k = 2.06) was found maximum for days to maturity followed by number of branches per plant. The genetic advance expressed as per cent of mean were found high for number of branches per plant, number of clusters per plant and seed yield per plant and. In F5, high genetic advance was recorded for the trait plant height. Genetic advance expressed as per cent of mean was high for number of branches per plant and seed yield per plant. High heritability coupled with high / moderate genetic advance was noted for days to maturity, number of clusters per plant and number of branches per plant in F4’s and plant height and number of branches per plant in F5’s. The values of genotypic correlation coefficient were higher than the phenotypic correlation coefficients. In F4, the character number of clusters per plant, number of pods per plant, pod length and number of seeds per pod had positive and significant correlation with seed yield per plant at phenotypic level. Genotypic correlations between above said traits were also positive and strong. Days to maturity and number of branches per plant also exhibited positive and significant genotypic association with seed yield per plant.Plant height had also recorded positive and significant associationwith number of branches per plant and number of pods per plant at phenotypic and genotypic levels.Number of clusters per plant exhibited positive and significant phenotypic and genotypic association with seed yield per plant. Number of pods per plant and pod length also had positive and significant association with seed yield per plant.In case of F5,the character number of branches per plant, number of clusters per plant, number of pods per plant and number of seeds per pod had positive and significant association with seed yield per plant at phenotypic as well as genotypic level.Number of branches per plant and number of clusters per plant had positive and significant association with number of clusters per plant and number of pods per plant, respectively at both phenotypic and genotypic levels. The number of clusters per plant had also positive and significant correlation with number of pods per plant at the both levels. High to moderate positive direct effects (genotypic and phenotypic) on seed yield per plant was recorded by plant height, number of clusters per plant, pod length and number of seed yield per plant in F4 population. The traits number of clusters per plant, number of pods per plant, pod length and number of seeds per pod was positively and significantly correlation with seed yield per plant at both the levels. In F4segregating populations, the best selection index was observed in five characters viz., seed yield per plant, number of pods per plant, pod length and number of seeds per pod. The next best index was made up by four characters viz., seed yield per plant, number of clusters per plant, number of pods per plant and plant height.While, in F5 segregating populations, the best selection index was observed in five characters viz., seed yield per plant, number of branches per plant, number of clusters per plant, number of pods per plant and number of seeds per pod. The next best index was made up by four characters viz., seed yield per plant, number of branches per plant, number of clusters per plant and number of pods per plant.ThesisItem Open Access GENETIC DIVERSITY AND SELECTION INDICES IN CASTOR (Ricinus communisL.) 2425(JAU,JUNAGADH, 2017-09) Umesh Chauhan; Dr. R. B. MadariyaKey words:Castor, Diversity, Selection indices, Variability A trial was conducted to assess variability, diversity and selection indices for seed yield and its attributes with a set of 64 genotypes of castor (Ricinus communis L.) at Main Oilseeds Research Station, Junagadh Agricultural University, Junagadh during Kharif 2016-17. Total12 quantitative characters were studied viz., days to 50% flowering of main raceme, days to maturity of main raceme, number of nodes up to main raceme, plant height up to main raceme, total length of main raceme, effective length of main raceme, number of capsules on main raceme, number of effective branches per plant, seed yield per plant, 100-seed weight, oil content and shelling out turn. The analysis of variance revealed highly significant differences among the mean square due to genotypes for all the twelve characters studied. A wide range of variation was observed for important yield components. High genotypic and phenotypic coefficient of variations, high heritability coupled with high genetic advance as per cent of mean was observed for all the characters except days to 50% flowering of main raceme, days to maturity of main raceme, oil content and shelling out turn. The genetic diversity analysis grouped the genotypes in ten clusters suggested the presence of considerable genetic diversity among the 64 genotypes studied. The clustering pattern indicated that geographic diversity was not associated with genetic diversity. The analysis of per cent contribution of various characters towards the expression of total genetic divergence indicated that seed yield per plantcontributed the maximum towards total genetic divergence followed by 100-seed weight, plant height up to main raceme, number of capsules on main raceme, total length of main raceme, number of effective branches per plant, oil content, days to 50% flowering of main raceme, effective length of main raceme. Based on the maximum genetic distance, it is advisable to attempt crossing of the genotypes from cluster X with the genotypes of cluster VIII, II and VII, which may lead to the generation of broad spectrum of favourable genetic variability for yield improvement in castor. The discriminant function indicated that selection based on multiple characters had higher genetic gain and relative efficiency over straight selection for seed yield per plant alone. There was an increase in genetic gain and relative efficiency with inclusion of an additional trait in the character combination. Selection index involving seed yield per plant, effective length of main raceme, number of capsules on main raceme, number of effective branches per plant and shelling out turn could be advantageously exploited in the castor breeding programmes. On the basis of overall studies, it can be concluded that due weightage should be given to seed yield per plant,number of capsules on main raceme, effective length of main raceme, shelling out turn and number of effective branches per plant while imposing selection for genetic improvement of seed yield in castor.Hybridization among diverse genotypes followed by pedigree method of selection would be beneficial to isolate transgressive segregants with high seed yield.ThesisItem Open Access GENETIC VARIABILITY, CORRELATION AND PATH COEFFICIENT ANALYSIS IN GARLIC (Allium sativum L.) 2419(JAU,JUNAGADH, 2017-08) CHOTALIYA POOJABEN SAVJIBHAI; Dr. G.U.KulkarniKey words: Garlic, traits, analysis of variance, variability, heritability, correlation, path analysis The present study was carried out to assess genetic variability, correlation coefficients and path coefficient analysis in 156 genotypes and 4 checks of garlic grown in Augmented Randomized Block Design at Vegetable Research Station, Junagadh Agricultural University, Junagadh during rabi season of 2015-2016. The observations were recorded on 21 characters viz., plant height (cm), number of leaves per plant, leaf length (cm), leaf width at middle portion (cm), days to maturity (days), pseudostem height (cm), collar thickness (cm), bulb collar diameter (cm), bulb equatorial diameter (cm), bulb polar diameter (cm), bulb weight (g), number of cloves per bulb, clove weight (g), clove length (cm), clove polar diameter (cm), clove equatorial diameter (cm), total soluble solids (%) and bulb yield (kg/ha), anthocyanin pigmentation, bulb shape, bulb colour. The analysis of variance revealed that mean squares due to genotypes were significant for all the traits except plant height, days to maturity indicating the presence of sufficient amount of genetic variability among the genotypes. Based on mean values with respect to characters, the genotype RGP-447 was the higher yielder followed by RGP-108, RGP-56, JGP-183 and RGP-384. The genotype RGP-447 was the top genotypes for the economic trait such as bulb weight. These genotypes might be utilized in further breeding programme for improvement in bulb yield. The value of the phenotypic coefficient of variation was higher than the corresponding genotypic coefficient of variation for all the characters which indicated effect of environment on the character expression. The GCV and PCV were higher for clove weight, bulb weight and bulb yield. Moderated GCV and PCV were observed for pseudostem height, clove equatorial diameter, number of cloves per bulb, bulb collar diameter, number of leaves per plant, leaf width at middle portion, collar thickness, leaf length, bulb polar diameter, clove polar diameter, clove length, bulb equatorial diameter, plant height. While bulb polar diameter, clove polar diameter, leaf length, clove length, bulb equatorial diameter, plant height, total soluble solids, days to maturity showed low GCV and PCV. High estimates of heritability was recorded for total soluble solids, clove weight, pseudostem height. Moderate heritability was obtained for clove equatorial diameter, bulb yield, bulb weight, number of leaves per plant, clove polar diameter, bulb polar diameter, leaf width at middle portion. Low value of heritability was recorded for bulb equatorial diameter, clove length, number of cloves per bulb, leaf length, bulb collar diameter, collar thickness, plant height and days to maturity. These characters would be effective in selection for garlic improvement. The genetic advance at 5% selection intensity (k=2.06) was found high for bulb yield followed by total soluble solids, bulb weight. Moderate genetic advance was observed for leaf length, pseudostem height, plant height, number of leaves per plant, number of cloves per bulb, while remaining all the traits, days to maturity, bulb polar diameter, clove weight, bulb equatorial diameter, clove polar diameter, clove equatorial diameter, leaf width at middle portion, clove length, bulb collar diameter and collar thickness exhibited the low genetic advance. A wide range of expected genetic advance as per cent of mean was observed for different characters. High estimates of genetic advance as per cent of mean was reported for the characters viz. clove weight, bulb weight, bulb yield, pseudostem height, clove equatorial diameter, number of leaves per plant, number of cloves per bulb, leaf width at middle portion, bulb collar diameter. High heritability along with high genetic advance as per cent of mean was observed for clove weight and pseudostem height. In this condition selection will be more effective for these characters might be under the control of additive gene effects. On the other hand low heritability with low genetic advance as per cent of mean was observed for bulb equatorial diameter, clove length, plant height and days to maturity. In general, the estimates of genotypic correlation were higher than the corresponding phenotypic correlation coefficient. It may result from the modifying effect of environment on the association of characters at genotypic level. The bulb yield was significant and positive correlation with characters like with plant height, number of leaves per plant, leaf width at middle portion, pseudostem length, bulb collar diameter, bulb equatorial diameter, bulb polar diameter, bulb weight and clove length, clove polar diameter and clove equatorial diameter. From these associations, it appears that higher bulb yield can be obtained by improving these characters. Path coefficient analysis revealed that the characters like plant height and clove polar diameter had high direct effect on bulb yield. These above characters also had positive indirect effect on each other. Plant height, number of leaves per plant, leaf width at middle portion, pseudostem height exhibited positive and indirect effects on bulb yield via plant height, leaf length, leaf width at middle portion, days to maturity, pseudostem height, bulb equatorial diameter, bulb polar diameter, bulb weight, number of cloves per bulb, clove weight and clove polar diameter, clove equatorial diameter and total soluble solids. Bulb collar diameter, bulb equatorial diameter, bulb polar diameter, bulb weight, clove length, clove polar diameter and clove equatorial diameter contributed indirectly by giving positive indirect effects on bulb yield through plant height, leaf width at middle portion, bulb equatorial diameter, bulb polar diameter, bulb weight, number of cloves per bulb, clove polar diameter, clove equatorial diameter and total soluble solids. The final conclusion that can be reached from variability, correlations and path coefficient analysis, it can be concluded that for yield improvement in garlic; plant height, number of leaves per plant, leaf length, pseudostem height, bulb collar diameter, bulb equatorial diameter, bulb polar diameter, bulb weight, number of cloves per bulb, clove weight, clove length, clove polar diameter, clove equatorial diameter were most important component characters. Hence, these traits should be considered as selection criteria for yield improvement in garlic.ThesisItem Open Access HETEROSIS AND COMBINING ABILITY ANALYSIS USING MALE STERILE LINES IN PEARL MILLET (Pennisetum glaucum (L.) R. Br.) 2401(JAU,JUNAGADH, 2017-07) ACHARYA ZEAL R.; Dr. M. D. KhanaparaKey Words: line x tester, pearl millet, heterosis, gene action and combining ability. The present investigation was undertaken in order to estimate the per se performance, extent of heterosis, general combining ability of parents and specific combining ability of hybrids in pearl millet for 13 characters. The crosses were attempted by using line x tester mating design among five male sterile lines and nine diverse testers during summer 2016. The resultant 45 hybrids alongwith 14 parents were tested using randomized block design with three replications at Sagadividi Farm, Junagadh Agricultural University,Junagadhduring kharif 2016. The analysis of experimental variance revealed that values of mean square due to genotypes were highly significant for all the characters indicating presence of sufficient amount of variability in the material studied. The parents differed significantly for all the characters except ear head lengthandear head girth.Further partitioning of parents into females, males and females vs males indicated that the mean square values due to males as well as females were significant for the characters, viz., grain yield per plant, days to 50% flowering, ear head weight, test weight, panicle index and total biomass per plant quantified the considerable amount of genetic diversity exit for these traits among the lines and testers. The mean squares due to femalesvs males were significant for grain yield per plant, days to 50% flowering, days to maturity, plant height, ear head girth, ear head weight, test weight, panicle index, total biomass per plant and harvest index indicating the significant difference between male and female parents for these traits. The hybrids differed completely from the parents for all the traits except days to 50% flowering, days to maturity and number of effective tillers per plantowing to significant mean squares due to parentsvs hybrids. This suggested the existence of overall heterosis and the significant difference between the parents and hybrids with respect to these characters. The study of per se performance of parents revealed thatthe male parentsJ-2508, J-2503 and J-2433 were the top performers for grain yield per plant among the all parents. The former two males also rank top for harvest index. Among the female parents,JMSA 20102 also ranked first for grain yield per plant, plant height and total biomass per plant. The male parent J-2507 and female parent JMSA 101 ware noticed for the lowest value for days to 50% flowering and days to maturity.The crosses JMSA 20102 x J-2496, JMSA 20102 x J-2479 and JMSA 20102 x J-2500 were found the superior among forty five hybrids.Moreover, at least one of the parents involved in the above superior crosses found high yielder and better for other yield attributes. This suggested that the parents involved in these hybrids had a strong tendency to transmit the higher gain to the off springs.The hybrids JMSA 101 x J-2500 was found the earliest among others for days to 50% flowering and days to maturity. A perusal of per se performance and heterosis indicated that hybrids JMSA 20102 x J-2496, JMSA 20102 x J-2479 and JMSA 20102 x J-2500 found the most promising for grain yield per plant and other desirable traits, hence could be further evaluated over environments to exploit the heterosis or utilized in future breeding programme to obtain desirable segregants for the development of superior genotypes. The hybrids JMSA 101 x J-2500 and JMSA 101 x J-2433 were observed significant and the highest negative heterosis over better parent for days to 50% flowering and days to maturity. Analysis of variance for combining ability revealed that the mean squares due to lines x testers were significant for number of nodes on main stem, number of effective tillers per plant, plant height, ear head length, ear head girth, ear head weight, test weight, panicle index, total biomass per plant, harvest index indicated the significant contribution of SCA variance. The variance for SCA component were higher than respective GCA variances component for grain yield per plant, number of nodes on main stem, number of effective tillers per plant, ear head length, ear head weight, test weight, panicle index, total biomass per plant, harvest indexsuggested relatively greater role of non-additive gene effects in the inheritance of all these traits. The estimates of general combining ability suggested that one female parent JMSA 20102 and three male parents J-2479, J-2496 and J-2503were found good general combiner for grain yield per plant. Moreover, these parents were also good combiners for other yield attributing characters. The parent JMSA 20102 found good general combiner not only for grain yield per plant but, also good combiners for days to maturity, number of nodes on main stem, number of effective tillers per plant, plant height, ear head girth, total biomass per plant, harvest index. Whereas, parents JMSA 101 was appeared to be good general combiner for other traits such as days to 50% flowering, plant height, test weight, panicle index, total biomass per plant. While, the parent J-2479 was good combiner for plant height, ear head weight, test weight, harvest index. The parents JMSA 101, JMSA 20102, J-2500 and J-2507 were found good general combiner for days to 50% flowering and days to maturity. The three superior crosses namely JMSA 20102 x J-2496, JMSA 20102 x J-2479 and JMSA 20102 x J-2500exhibited higher per se performance, positively significant and high magnitude of heterobeltiosis as well as standard heterosis and significant sca effects for grain yield per plant. These hybrids also registered significantly higher heterosis and sca effects in desired direction for other yield attributing components. Therefore, these hybrids could be further evaluated over years and locations in diverse environments to exploit for commercial cultivation.ThesisItem Open Access HETEROSIS AND COMBINING ABILITY ANALYSIS FOR SEED YIELD AND ITS COMPONENTS IN SESAME (SesamumindicumL.) 2386(JAU,JUNAGADH, 2017-07) Mungala Rahul A.; Dr. V. J. BhatiyaKey Words: Combining ability, Gene action, Heterobeltiosis, Sesame, Standard heterosis The present investigation on “Heterosis and combining ability analysis for seed yield and its components in sesame (Sesamum indicum L.)” was carried out at Sagadividi Farm, Department of Seed Science and Technology, College of Agriculture, Junagadh Agricultural University, Junagadh during Summer 2016. The experimental material comprising by 8 lines, 5 testers, their resulting 40 hybrids and standard check Guj.Til-2 were grown in order to estimate heterosis, combining ability and nature of gene action involved in the inheritance of seed yield per plant (g) and its components viz., days to 50 per cent flowering, days to maturity, plant height (cm), height to first capsule (cm), number of branches per plant, number of internodes per plant, length of capsule (cm), width of capsule (cm), number of capsules per plant, number of capsules per leaf axil, number of seeds per capsule, 1000-seed weight (g) and oil content (%). The experiment was conducted in Randomized Block Design with three replications. Observations were recorded on five competitive randomly selected plants per replication per treatment for all the characters except days to 50 per cent flowering and days to maturity, which were recorded on plot basis and the mean values were subjected to analysis of variance, estimation of heterosis and combining ability analysis. The analysis of variance for experimental design revealed highly significant differences among genotypes and hybrids for all the characters indicating the presence of sufficient amount of genetic variability for all the fourteen traits studied. While, differences among parents were also found highly significant for all traits. Mean squares due to parents vs hybrids were also found highly significant for all the characters except for length of capsule, width of capsule, 1000-seed weight and oil content. High magnitude of heterosis was observed for days to 50 per cent flowering, number of branches per plant, number of internodes per plant, number of capsules per plant, number of seeds per capsule, 1000-seed weight and seed yield per plant. Whereas, the magnitude of heterosis was moderate for plant height, height to first capsule, length of capsule, and low for days to maturity, width of capsule and oil content. The heterobeltiosis for seed yield per plant ranged from -46.82 per cent to 50.00 per cent, while the standard heterosis ranged from -25.96 per cent to 77.81 per cent. The cross RT 33 x Guj.Til-10 recorded the highest standard heterosis for seed yield per plant followed by DPI 1484 x Guj.Til-2, TC 66 x Guj.Til-2 and DPI 1484 x Guj.Til-1. These crosses also exhibited desirable heterosis for important yield attributes suggesting that the heterosis for seed yield was associated with heterosis for component characters. Analysis of variance for combining ability revealed that the mean squares due to lines, testers and lines x testers were significant for all the characters except for mean squares due to testers for number of seeds per capsule and due to lines x testers interaction, except for plant height and oil content, which indicated the importance of both additive and non-additive genetic variances in the expression of these characters. Higher magnitude of σ2gca as compared to σ2sca for characters i.e. plant height, number of internodes per plant and oil content indicated the involvement of additive gene action. Higher magnitude of σ2sca than σ2gca observed for all the remaining eleven characters including seed yield per plant, indicated that the predominance of non-additive gene effects in the inheritance of these characters. The lines IC 96128, TC 66 and DPI 1484 and the testers Guj.Til-4 and Guj.Til-3 displayed high gca effects and good per se performance for seed yield per plant and some desirable traits. These parents possessed high concentration of favourable genes for more number of traits and should be utilized in multiple crossing programmes. The sca effect of the crosses indicated that eleven hybrids manifested significant and positive sca effects for seed yield per plant. Among these, the best three specific combiners were RT 33 x Guj.Til-10, LIMDI 9 x Guj.Til-1 and TC 66 x Guj.Til-2. These crosses also showed desirable sca effects for important yield traits. The crosses exhibiting high sca effects involved either average x good, good x poor, average x poor, poor x average, poor x poor or good x good general combiners for majority of characters indicating the presence of additive x dominance, dominance x dominance and additive x additive type of gene interactions. The use of recurrent selection or biparental mating followed by pedigree selection may proved to be effective in simultaneous exploitation of both the type of gene actions for improvement of seed yield and its attributes in sesame.ThesisItem Open Access GENETIC VARIATION AND INTERRELATIONSHIP STUDIES IN F2 GENERATIONS OF GROUNDNUT (Arachis hypogaea L.) 2385(JAU,JUNAGADH, 2017-07) C. K. Patel; Dr. J. H. VachhaniKey Words: Variability, Correlation and Path analysis Groundnut is one of the most important oilseed crop. To know the extent of variability for yield related traits and their associations with other traits particularly in segregating population of groundnut, this study was undertaken. The experimental material consisted of six F2s and their twelve parents of groundnut. The experiment was laid-out in Randomized Block Design with three replications. The required quantity of seeds of F2s and parents of six crosses were obtained from the Research Scientist (Groundnut), Main Oilseeds Research Station, Junagadh Agricultural University, Junagadh and was sown in the summer, 2016 at the Main Oilseeds Research Station, Junagadh Agricultural University, Junagadh. A set of 12 parents and their 6 F2s of groundnut (Arachis hypogaea L.) were utilized to estimate genetic variability, correlation and path analysis. The observations on randomly selected five plants of parents and fifty plants of F2s from individual plot were recorded for nine characters, viz., days to appearance of first flower, days to maturity, number of primary branches per plant, plant height, number of matured pods per plant, number immature pods per plant, kernel yield per plant, shelling outturn and pod yield per plant. The mean sums of squares due to genotypes, parents as well as F2s were highly significant for all the characters indicating thereby sufficient variability in the materials studied. The mean sums of squares due to parents versus crosses in all the characters indicated significant deviation of F2 population from the parents. The results indicated that differences among the genotypes found significant across the crosses for all the characters. Crosses under study were exceeded the range of their respective parents either in negative or positive directions indicating transgressive segregation in all the characters, should be exploited to select for individual superior to the parents. The estimates of genotypic coefficient and phenotypic coefficient of variances were found moderate to high in magnitude in most of the crosses for all the characters except in days to appearance of first flower and days to maturity. Moderate heritability values were noticed for most of the characters. Genetic advance expressed as percentage of mean was also moderate to high in most of the characters. High heritability along with high genetic advance and high value of GCV and PCV for pod yield per plant in Cross 2 and Cross 6 in kernel yield per plant were exhibited by the F2 population. Thus, it can be concluded that this Cross 6 for kernel yield per plant and Cross 2 for pod yield per plant was mainly under the influence of additive gene actions and selection would be effective for improving these traits. Pod yield per plant had significant and positive association with number of matured pods per plant, kernel yield per plant and shelling outturn. These characters can be considered as selection criteria for higher yield as they were mutually and directly associated with pod yield per plant. Out of nine characters studied, kernel yield per plant exerted maximum positive direct effect on pod yield per plant. Indirect effect of number of matured pods per plant and shelling outturn through kernel yield per plant were high. When both direct and indirect contribution were considered for number of matured pods per plant, kernel yield per plant and shelling outturn were proved to be an outstanding characters influencing pod yield per plant in groundnut.ThesisItem Open Access VARIABILITY, CORRELATION AND PATH ANALYSIS IN CASTOR (Ricinuscommunis L.) 2383(JAU,JUNAGADH, 2017-07) Mr. H. M. Movaliya; Dr. V. P. ChovatiaKey words: Variability, Correlation, Path analysis and castor A trial was conducted to assess variability, correlation and path analysis for seed yield and its attributes with a set of 64 genotypes of castor (RicinuscommunisL.) at Main Oilseeds Research Station, Junagadh Agricultural University, Junagadh during Kharif2016-17. The characters studied were 12 quantitative characters viz., days to 50% flowering of main raceme, days to maturity of main raceme, number of nodes up to main raceme, plant height up to main raceme, total length of main raceme, effective length of main raceme, number of capsules on main raceme, number of effective branches per plant, seed yield per plant, 100-seed weight, oil content and shelling out turn. The analysis of variance revealed highly significant differences among the mean square due to genotypes for all the twelve characters studied. A wide range of variation was observed for important yield components. High genotypic and phenotypic coefficient of variations, high heritability coupled with high genetic advance as per cent of mean was observed for all the characters except number of nodes up to main raceme and number of effective branches per plant. Seed yield per plant had significant and positive correlation with total length of main raceme, effective length of main raceme, number of capsules on main raceme and oil content. While days to maturity of main raceme had significant and desirable correlation with seed yield per plant. Days to 50% flowering of main raceme, number of nodes up to main raceme, number of capsules on main raceme, 100-seed weight, oil content and shelling out turn exhibited positive and high direct effects on seed yield per plant while number of effective branches per plant exerted positive but moderate direct effect towards seed yield per plant at genotypic level. Number of effective branches per plant, effective length of main raceme, number of capsules on main raceme, plant height up to main raceme and oil content exhibited positive and high direct effects on seed yield per plant while total length of main raceme, 100-seed weight, shelling out turn and days to maturity of main raceme exerted positive and moderate direct effects towards seed yield per plant at phenotypic level. On the basis of all the studies, it can be concluded that due to weightage should be given to total length of main raceme, effective length of main raceme, number of capsules on main raceme, 100- seed weight, oil content while imposing selection for genetic improvement of seed yield in castor.