Identification of molecular markers associated with tolerance of rice (Oryza sativa L.) to submergence during germination

Date

4-2008

Degree

Bachelor of Science in Biology

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Celia B. Dela Viña

Abstract

In order to identify molecular markers associated with tolerance of rice to submergence during germination, BC2F1 populations from the cross between Samba Mahsuri (a susceptible megavariety) and Khaiyan (a tolerant variety) were genotyped and their BC2F2 were phenotyped. Two of the BC2F1 populations (IR83774-SP-1 and 1R83774-1G-2) were genotyped using 99 simple sequence repeat (SSR) markers covering the 12 chromosomes. Polyacrylamide gel electrophoresis was performed and the allelic bands of the plants were scored. BC2F1 seeds from the same populations were subjected to anaerobic germination screening. Percent germination of seeds submerged in 5-7 cm of water for 21 days was observed. Genotypic and phenotypic data sets from BC2F1 and BC2F1, respectively. were entered into QGene to find putative QTLs. Based on one replication showing the most normal distribution, five putative QTLs were revealed. namely qAG-2-1 with the highest LOD score (6.47), and qAG-2-2, qAG-4, qAG-5 and qAG-6 with lower LOD scores. The peak markers identified were RM13570, RM424, RM471, RM274 and RM400. The first two were located on chromosome 2 and the last three on chromosomes 4, 5 and 6, respectively. Using genotypic data, Graphical GenoTyping (GGT) was used to identify regions of introgression in the BC2F1 plants. The introgression of the QTLs identified using QGene appeared to effectively confer tolerance. Fine-mapping of these regions and improved anaerobic germination screening methods might facilitate better identification of QTLs.

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