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Birsa Agricultural University, Ranchi

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1989 - 198911990 - 19961
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Subject: Plant Breeding × End date: 2022 × Thesis Type: M.V.Sc. ×
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    ThesisItemOpen Access
    Combining Ability And Heterosis Studies In Linseed (Linum sitatissimum L.)
    (Birsa Agricultural University, Ranchi, 1996) Sohan Ram; H.B.P.Trivedi
    Linseed is predominantly a autogamous crop of industrial significance. Inspite of considerable increase in area and production under linseed, the productivity which is of foremost importance, is still stagnant in India. The prime objective of the present investigation was to evaluate some well recognised varieties and explore the combining ability variances of oil yield and seed yield components and their combining ability effects together with the studies on variability, heterosis and correlation through dialled analysis. Eight well recognised varieties of major linseed growing states were obtained from Project Co-ordinator (Linseed), Chandra Shekhar Azad University of Agriculture and Technology, Kanpur. These varieties were crossed in 8 x 8 diallel fashion to obtain 28 direct and 28 reciprocal F1 hybrids. These hybrids were generation advanced in off season nursery to procure F2 seeds. These F1 and F2 hybrids were evaluated separately along with the parents for variability, heterosis, inbreeding depression, combining ability and correlation co-efficient. The analysis of variance was highly significant for oil yield and its components. Variability in the parents and reciprocals, though was non-significant yet was significant in Parents Vs Crosses and F₁ Vs Reciprocals. Manifestation of heterosis was variable in magnitude and nature among corresponding characters in F₁ and F2 hybrids of direct and reciprocal cross. Heterosis as high as 230.90 percent over superior parent was obtained for oil yield in R-7 x Garima, 69,01 percent for oil content in T 397 x R-7 and 202.34 percent for seed yield in Jawahar-23/10 x Garima.Cross Mukta x R-7 was identified as highest heterotic cross for oil yield, seed yield and oil content. CONT Use of parent as pollen or seed parent had a significant difference in heterotic behaviour of the cross. Parents Neelum, Garima and R-17 were identified as best seed parents against R-7 and Jawahar-23/10 as pollen parents. Estimates of GCA and SCA variances obtained were highly significant for oil yield and its components, Non-additive components played major role in expression of oil yield, oil content and seed yield where as other characters exhibited importance of additive component in their expression. The general combining ability effects corresponded fairly with that of per se performance of the parents for all characters except oil content, number of capsules and number of secondary branches per plant. For oil yield, oil content and seed yield though none of the parent was best / good general combiner, yet best / good specific combinations for these traits were obtained from poor x poor combiners. It was noticed that high specific combinations for oil yield were also high specific combinations for seed yield but all high specific combinations for oil content and seed yield components were not necessarily high specific combinations for oil yield. Genotypic correlation co-efficient was higher than phenotypic. Correlation Oil yield was favorably associated with oil content, seed yield, number of capsules and number of secondary branches. Selection of these characters was suggested to increase oil yield.
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    ThesisItemOpen Access
    Studies On Variability In Gram Under Late Sown Condition
    (Birsa Agricultural University, Ranchi, 1989) Mukherjee, Ajit Kumar; Fazlul Haque
    The phenotypic and genotypic variability, the phenotypic and genotypic correlations and path coefficient studies were made in a collection of forty two varieties of gram (Cicer arietinum L.) of diverse origin in nine quantitative plant characters under late sown condition in typical medium paddy fallows. Highly significant differences were observed in those varieties for all the plant characters studied, except for one character i.e. harvest index. Days to 50% flowering. plant height, number of pods per plant, 100-sead weight, seed yield par plant, days to maturity and harvest index showed a wide range in their phenotypic variability. Number of seeds par pod and number of branches per plant expressed very narrow range of phenotypic variability. The estimate of phenotypic as well as genotypic coefficient of variation were maximum for seed yield per plant, followed by number of pods par plant, 100-seed weight and plant height. Low level of genetic coefficient of variation was observed in days to maturity, harvest index and days to 50% flowering. Days to 50% flowering and days to maturity gave the highest value of heritability expressed in broad sense, while harvest index had the lowest estimate. The three parameters i.e. genetic coefficient of variation, heritability estimates and genetic advance in percentage of mean, considering together revealed that seed yield per plant, number of pods par plant and 100-seed weight might be under control of additive gene effect. Seed yield per plant exhibited highly significant genotypic and phenotypic association with number of poda per plant, days to maturity and harvest index. Plant height and 100-seed weight showed negative association with seed yield per plant, both phenotypically and genotypically. The harvest index had the maximum direct effect on seed yield per plant. For the grain yield improvement in these varieties of gram number of pods per plant, days to maturity and harvest index are the three important yield contributing characters for selection under late sown rainfed condition.