Discovery of QTL for root traits and water use efficiency in rice (Oryza sativa L.) and their validation - A combined approach of association analysis and linkage mapping
| dc.contributor.advisor | M. S, Sheshshayee | |
| dc.contributor.author | B. R, Raju | |
| dc.date.accessioned | 2016-05-20T13:55:13Z | |
| dc.date.available | 2016-05-20T13:55:13Z | |
| dc.date.issued | 2013-08-24 | |
| dc.description.abstract | Introgression of water mining and water use efficiency (WUE) traits on to a single elite genetic background is needed while developing aerobic worthy rice cultivars. Considering the complexity of inheritance of these traits, a focused molecular breeding is a promising approach. A set of 173 diverse indica rice accessions were phenotyped for these traits and significant variability was noticed which was consistent across seasons, indicating a strong genetic control. Assessment of molecular diversity using 291 SSR markers detected a total of 2,615 alleles with an average of 8.95 allele per locus and an average PIC value of 0.6. Population structure analysis identified six main subgroups which corresponded to the diversity analysis derived from neighbour joining method. Of the 108 significant marker-trait associations (MTAs) identified using mixed linear model, 51 were highly significant (P<0.01). There were 24 associations for Root traits and 1 for 13C and 16 for other physiological traits. Many of these markers were found to be located in QTL regions previously reported for similar traits. A trait specific mapping population was characterized for root traits and WUE under aerobic conditions validating the associated markers. Significant phenotypic variations with transgressive segregants were found for all the traits and 30 QTLs were detected. The combined approach of association and linkage mapping lead to the identification of several common markers viz., RM1235, RM8020, RM4477, RM163 and RM307 linked with the traits of interest. These markers can significantly enhance breeding efficiency in introgressing complex traits. This novel two pronged strategy lead to the discovery of 13 robust QTLs which on in-silico analysis revealed the presence of genes that govern variability in cellular metabolism, transport and signal transduction, transcription and hormonal regulation under abiotic stress adaptation and yield improvement in rice. | en_US |
| dc.identifier.other | Th-10606 | |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/66171 | |
| dc.language.iso | en | en_US |
| dc.publisher | University of Agricultural Sciences, Bengaluru | en_US |
| dc.sub | Crop Physiology | |
| dc.subject | vegetative propagation, grain, rice, yields, irrigation, developmental stages, biological phenomena, planting, genetics, weather hazards | en_US |
| dc.these.type | Ph.D | |
| dc.title | Discovery of QTL for root traits and water use efficiency in rice (Oryza sativa L.) and their validation - A combined approach of association analysis and linkage mapping | en_US |
| dc.type | Thesis | en_US |