Assessment of genetic variability in exotic germplasm of rice (Oryza sativa L.)
| dc.contributor.advisor | Indra Deo | |
| dc.contributor.author | Amit Kumar | |
| dc.date.accessioned | 2022-01-24T06:57:18Z | |
| dc.date.available | 2022-01-24T06:57:18Z | |
| dc.date.issued | 2021-12 | |
| dc.description.abstract | The present investigation entitled Assessment of Genetic Variability in Exotic Germplasm of Rice (Oryza sativa L.) was undertaken to: (i) evaluate the rice germplasm lines for yield and yield components, (ii) estimate correlation coefficients between different characters, (iii) study direct and indirect effects of yield components on grain yield by path coefficient analysis, and (iv) examine genetic divergence existing in the germplasm collections of the present study. In the present investigation, 299 genotypes of rice germplasm collections, including three checks, showing wide spectrum of variation for various characters, were evaluated in under timely sown and irrigated conditions during Kharif, 2019. The experiment was conducted in augmented design having two blocks at the Norman E. Borlaug Crop Research Centre, Pantnagar. The characters studied were days to 50% flowering, yield/plot, yield kg/h, Plant height (cm), number of tiller/plant, number of filled grain, number of unfilled grain, spikelet fertility (%), 1000 grains weight (g), seed length (mm), seed breadth (mm), L/B ratio. The mean, range, and least significant differences, correlations, path-coefficients and genetic divergence were all calculated using the data from these thirteen characters. The genotype, EC19-100 (8209.32 kg) produced highest grain yield per plant followed by EC19-50 (7403.76 kg), EC19-107 (5948.19 kg), EC19-102 (4987.07 kg) and EC19-19 (5014.85 kg). These five genotypes showed good mean performance for these genotypes. These genotypes could be utilised as parents in a rice hybridization effort aiming at creating high-yielding cultivars. Grain yield per hectare exhibited highly significant and positive correlations with yield per plot and 1000 grain weight and seed length. Path analysis identified Grain yield per plot, followed by spikelet fertility and number of filled grains employed very high order positive direct effects on grain yield per hectare while seed breadth, number of effective tillers per plant, days to 50% flowering and panicle length showed as most important indirect yield components. The Non-hierarchical Euclidean cluster analysis grouped 299 genotypes in to eight clusters. The highest inter-cluster distance was observed between cluster III and VII (6.125) indicating very high degree of genetic diversity between these two clusters. The lowest inter-cluster distance was observed between cluster VI and VIII (1.556), followed by cluster III and VI (1.898) and cluster I and II (1.938). The highest inter-cluster distance was recorded between cluster III and VII (6.125) indicating very high degree of genetic diversity between these two clusters. Thus, crossing of single genotype of cluster III, namely, EC19-19, EC19-65, EC19-107, EC19-108 and EC19-187 with EC19-171, EC19-259, and EC19-283 of cluster VIII is recommended obtaining transgressive segregants for developing high yielding lines of rice. Similarly, crossing of EC19-287 and EC19-271 belonging to cluster VIII with promising genotypes of clusters having very high inter cluster distances from it, namely, EC19-43, EC19-50, EC19-55, EC19-74, EC19-100, EC19-153, EC19-158 and EC19-199 of cluster II is also recommended for isolating desirable segregants. | en_US |
| dc.identifier.uri | https://krishikosh.egranth.ac.in/handle/1/5810181170 | |
| dc.keywords | genetic variation, exotics, germplasm, improved varieties, rice | en_US |
| dc.language.iso | English | en_US |
| dc.pages | 116 | en_US |
| dc.publisher | G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand) | en_US |
| dc.research.problem | Rice | en_US |
| dc.sub | Genetics and Plant Breeding | en_US |
| dc.theme | Genetic Parameters | en_US |
| dc.these.type | M.Sc | en_US |
| dc.title | Assessment of genetic variability in exotic germplasm of rice (Oryza sativa L.) | en_US |
| dc.type | Thesis | en_US |