GENETIC DIVERGENCE ANALYSIS IN RICE (Oryza sativa L.)
KrishiKosh
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Title |
GENETIC DIVERGENCE ANALYSIS IN RICE (Oryza sativa L.)
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Creator |
VENKATA LAKSHMI, M
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Contributor |
SUNEETHA, Y
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Subject |
grain, yields, planting, genetics, genotypes, developmental stages, rice, biological phenomena, heritability, phenotypes
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Description |
The present investigation entitled “Genetic divergence analysis in rice (Oryza sativa L.) was undertaken at College Farm, Agricultural College, Naira, Srikakulam during Kharif 2012. The experimental material comprised of 70 genotypes and were evaluated in a randomized block design with three replications. Observations were recorded on days to 50 per cent flowering, days to maturity, number of effective tillers per plant, plant height, panicle length, number of grains per panicle, 1000-grain weight, grain yield per plant, kernel length, kernel breadth and L/B ratio. The main objectives of the investigation were to study the genetic diversity present in the material for selection of diverse parents, to estimate the genetic parameters among the genotypes for yield and quality traits and the extent of association between yield, its components and quality characters including the direct and indirect effects. The analysis of variance revealed significant variation among the genotypes for all the traits studied, indicating the existence of sufficient variability in the material under study. High GCV and PCV values were observed for grain yield per plant while moderate values were noticed for number of effective tillers per plant, plant height, number of grains per panicle, 1000-grain weight, kernel breadth and L/B ratio. High heritability coupled with high genetic advance as per cent of mean was observed for number of productive tillers per plant, plant height, number of grains per panicle, 1000- grain weight, grain yield per plant, kernel breadth and L/B ratio, which indicated the pre-dominance of additive gene action in the inheritance of these traits. The high estimates of heritability coupled with low genetic advance as per cent of mean were noticed for days to maturity indicating the presence of non-additive gene effects, in addition to environmental influence. The genotypes studied were grouped into nine clusters based on the genetic divergence studies. Among the nine clusters, cluster IV was the largest comprising of 14 genotypes, representing collections from different centres of the country. The distribution pattern of genotypes into different clusters revealed no parallelism between genetic and geographic diversity. Maximum intra cluster D2 values were recorded for Cluster IX indicating the genotypes in the cluster to be more divergent. Further, highest inter-cluster divergence was noticed between cluster II and IX, indicating that genotypes from these clusters were highly divergent meriting due consideration in selection of parents from these clusters for hybridization. Further, L/B ratio was noticed to contribute maximum, followed by number of grains per panicle, kernel length and plant height towards the total divergence indicating the need to emphasis on these traits in the selection of parents for hybridization. A perusal of the results on character associations for grain yield, yield components and quality characters revealed grain yield per plant to be positively and significantly associated with days to maturity, number of productive tillers per plant, plant height and kernel length indicating importance of these traits as selection criteria in yield improvement programmes. An analysis of the path coefficient results also revealed high direct effect of kernel length, number of ear bearing tiller per plant, plant height and days to maturity on grain yield indicating the effectiveness of direct selection for these traits. The study also revealed the potential of CR 2986-2-3-1-1-1 and CR 2942-112 genotypes for grain yield per plant in addition to panicle length, number of grains per panicle and 1000-grain weight indicating their scope for use in different hybridization programmes and the genotypes RP BIO 4919-194, R 1521-880-1-37-1, CN 1476-817- 8-19-8 and OM 5637 are identified as promising genotypes for improving the yield |
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Date |
2016-06-23T10:24:31Z
2016-06-23T10:24:31Z 2013 |
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Type |
Thesis
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Identifier |
http://krishikosh.egranth.ac.in/handle/1/67799
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Language |
en
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Relation |
D9456;
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Format |
application/pdf
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Publisher |
ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY
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