Exploiting the multiparent advanced generation intercross (Magic) indica populations of rice (Oryza sativa L.) for seedling salinity tolerance and establishing the genetic correlations of the selected genotypes.

Date

4-2012

Degree

Bachelor of Science in Biology

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Neilyn O Villa

Co-adviser

Glenn B. Gregorio

Abstract

Seedling salinity tolerance characteristic of MAGIC Indica population of rice (Oryza saliva L.) was investigated through phenotypic screening, measuring morpho-physiological parameters and SSR analysis. From the original 970 MAGIC rice genotypes. 205 genotypes were initially selected. After a second screening, 36 lines were subjected to a final replicate screening along with eight founder lines of MAGIC Indica. and the two checks. Thirteen genotypes (30%) scored as tolerant, 29 (64%) scored as moderately tolerant, one (2%) line scored as sensitive, IR 29 (2%) scored as highly sensitive while two founder lines failed to germinate. Relatively, the percent reduction in fresh weight content for shoot biomass was observed to be higher among the genotypes than percent reduction in dry weight content. A reverse trend was observed for percent reduction in root biomass. Genotypes under normal treatment were observed to have longer roots (14.250 to 35.000) and shoots (41.000 to 63.000) than treatments under salt stress. Relatively, the Na/K ratios of selected lines under salt stress were higher than FL 478. A total of 32 SSR markers were used revealing 93 alleles. Twenty markers exhibited locus heterozygosity while five markers were monomorphic. RM 490 exhibited the highest PIC (0.5869) while RM 178 exhibited the lowest (0). Haplotype analysis generated 44 haplotypes with respect to FL 478. No consistent clustering relationship based on SES scores and Na/K ratio was observed which can be attributed to the inherent genetic diversity in the population which may have created a novel salinity tolerance mechanism.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

Thesis

Document Type

Thesis

This document is currently not available here.

Share

COinS