Molecular marker based bulk segregant analysis for blast resistance in aromatic rice
| dc.contributor.advisor | Kumar, J. | |
| dc.contributor.author | Singh, Balwant | |
| dc.date.accessioned | 2016-07-12T11:53:23Z | |
| dc.date.available | 2016-07-12T11:53:23Z | |
| dc.date.issued | 2010-08 | |
| dc.description | Thesis-PhD | en_US |
| dc.description.abstract | Basmati is considered as the best quality rice in world market and fetches highest premium. But some of the non-Basmati scented rices, which include some Kalanamak accessions, are much superior to Basmati-types with respect to all other traits except grain length. Many of the traditional small and medium grained scented rices fetch higher price than Basmati in their native areas of cultivation. There is, however, an urgent need to properly characterize and improve these rices for useful traits such as aroma, quality and resistance to biotic (blast) and abiotic (salinity) stresses. Vast diversity in these rices strengthens the necessity to develop designer’s varieties of scented rices with desired traits as per consumers’ requirements, which in turn should offer a great advantage in both national and international market. In the present investigation, thus an effort was made for the improvement of the Kalanamak accessions against rice blast and quality and agro morphological traits. A set of 50 rice accessions, including 24 Kalanamak accessions, was characterized on the basis of agro-morphological characters, quality traits and SSR molecular markers. The mean values of the traits were found to be significant, indicating that there were significant differences in different morphological and grain quality characteristics of the scented rice genotypes selected for the study. The mean value of morphological trait, plant height varied from 100.83 to 177.4, number of panicles varied from 6 to 12, panicle length varied from 24 to 34, 50% flowering varied from 93 to 147.67 and days to maturity ranged from 123 to 183.67. The mean value of quality trait, L/B ratio ranged between 2.5-3.0, alkali spread value between 4-5, elongation ratio between 1.8-2.2 and strong aroma were found among most of the genotypes studied. With collective score of all the morphological and quality traits, genotype PB-1 was found to be most suitable genotype for improvement of Kalanamak accessions. Five Kalanamak accessions viz., 3216, 3327, 3119, 3131 and 3122 were also found suitable and selected for breeding programme. Cluster analysis clearly differentiated all the accessions into different subgroups. Molecular marker analysis clustered blast resistant genotypes in the same group with more than 80% similarity and rest of the genotypes showed about 50% similarity. The parents selected on the basis of their resistance against blast under controlled conditions, wherein isolates from different geographical regions were used for challenge inoculation, also showed similar resistant pattern at the blast hot spot at Hawalbagh (Almora). The pattern of blast resistance found in the parents 3131SN, 3327 and 3131SN was found to be similar to the IRRI differential lines, IRBLks-F5 (gene Pik-s), IRBLz-Fu (gene pi-z), and IRBLz5-CA (piz-5). Molecular marker analysis confirmed the presence of above mentioned genes in the parents. Chi-square values for disease resistance were good fit to the Mendalian ratio of 3:1 among all the F2 populations. Significant correlation was found between most of the markers and resistance phenotype, however PVE ranged from 9.52% for marker lc-19 in population B to 37% for lc-22 for population C. Bulk segregant analysis proved close association of the resistance gene(s) with their respective makers. All the segregants showed discrete pattern of segregation for blast resistance. Screened morphological traits showed continuous segregation among all the progenies. All the F2 populations viz: A, B, C, D, E and F showed resistance to blast to a good extent. Along with blast resistance, population E showed reduction in plant height and population C and E showed early maturation. The segregants found promising for the desired traits would be advanced to the next generation. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/68638 | |
| dc.language.iso | en | en_US |
| dc.publisher | G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand) | en_US |
| dc.sub | Molecular Biology and Biotechnology | |
| dc.subject | molecular markers, rice, segregation, blast, disease resistance, characterization, biotic factors, abiotic factors, soil salinity, cluster analysis | en_US |
| dc.these.type | Ph.D | |
| dc.title | Molecular marker based bulk segregant analysis for blast resistance in aromatic rice | en_US |
| dc.type | Thesis | en_US |