Genetic and Molecular Analysis of the Rj(7) Gene in Soybean Using Pcr-Based Technologies

The Williams-derived hypernodulating NOD mutants and the Enrei-derived En6500 mutant are genetically controlled by single recessive genes. However, from our previous studies it was unclear whether there exists an additional mutant gene independent of rj7 conferring mutations in the NOD2-4 and NOD3-7 mutants. For molecular genetics, no research work has been done in attempts to investigate molecular biology of rj 7 in the NOD mutants. The purposes of the present studies were to determine if there exists an additional mutant gene independent of rj 7 and to identify DNA molecular markers associated with rj 7. Genetic study of NOD3-7 revealed that a single recessive mutant gene was responsible for hypernodulating mutation in this line. Using hypernodulating pure lines exhibiting purple colored hypocotyl as a phenotypic marker for allelism analysis, it was concluded that the NOD2-4 and NOD3-7 mutants carried the same mutant allele at the rj7 locus. There was not an independent mutant locus in NOD2-4 as speculated previously. Simple sequence repeat (SSR), random amplified polymorphism DNA (RAPD), and amplified restriction length polymorphism (AFLP) technologies were used for molecular genetic studies. The bulked segregant analysis and segregation analysis were performed for the detection of DNA markers. The results indicated that among the marker systems used there was no SSR marker found, whereas four RAPD and six AFLP DNA markers were identified to be linked to this mutant allele, mostly in coupling phase linkage. These markers were also found to be highly he ritable in backcrosses and descendent generations. Genetic linkage maps of the chromosomal region around the rj7 locus were constructed using the MAPMAKER program. It is concluded that PCR-based DNA polymorphism technologies provided powerful and effective tools to detect DNA markers linked to the rj7 gene. Although no SSR markers were found, several RAPD and AFLP DNA markers were identified to be associated with rj 7 and mapped in a range of linkage distances in the vicinity of the locus. These markers can be used for a DNA diagnostic approach or for marker-assisted selection in soybean.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Agronomy

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Vuong, Tri Dinh

Contributors dc:contributor

• Harper, James E.

• Biology, Molecular

Language dc:language

eng

Identifier

(MiAaPQ)AAI9912414

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/87678