Analysis of introgression from a tetraploid wild species, Oryza minuta, into cultivated rice, O. sativa

Chee, Fong Tyng (2002) Analysis of introgression from a tetraploid wild species, Oryza minuta, into cultivated rice, O. sativa. Masters thesis, Universiti Malaysia Sabah.

Analysis of introgression from a tetraploid.pdf

Download (710kB) | Preview


Oryza minuta, a tetraploid wild relative of cultivated rice, is an important source of resistance genes to bacterial blight (BB). Advanced backcross progenies (monosomic alien additional lines, MAALs and introgression lines) have been derived from interspecific cross, O. sativa x O. minuta using O. sativa as recurrent parent. Fifty-nine putative MAALs and 158 introgression lines have been examined for the presence of resistance gene(s) from O. minuta. Chromosome analysis, screening for BB resistance, isozyme analysis and microsatellite or simple sequence repeat (SSR) analysis were carried out to detect alien introgression. Seventeen plants were detected with an extra chromosome through cytogenetic analysis and have been identified as MAALs. Of 158 introgression lines, 17 were found to be resistant to race 1 (PX061) of BS of Philippines, but none of the putative MAALs were resistant. Isozyme analysis of 110 backcross derivatives did not reveal introgression from O. minuta in all isozymes studied (AMP, SOH, ADH, lCD, GOT, MAL and PGD). However, 11 progenies showed allele 2 of Adh1 and four progenies showed allele 2 of Pgd1, while another 17 progenies showed allele 2 in both Adh1 and Pgd1. All these alleles were not found in both parents. Unfortunately, none of these progenies were resistant to race 1 of BS of Philippines. Introgression was detected using SSR marker. SSR markers showed about 28% polymorphism between O. sativa and O. minuta. Of the 76 polymorphic SSR markers used, 28 markers detected introgression from O. minuta. SSR analysis of the putative MAALs and introgression lines indicated that small segments from O. minuta had been transferred into O. sativa. The results from this study showed SSR markers are efficient markers for detecting introgression.

Item Type: Thesis (Masters)
Keyword: Oryza minuta, cultivated rice, bacterial blight, O. sativa
Subjects: T Technology > TP Chemical technology
Department: FACULTY > Faculty of Science and Natural Resources
Date Deposited: 04 Apr 2018 16:17
Last Modified: 04 Apr 2018 16:17

Actions (login required)

View Item View Item