Molecular, Genetic, and Agronomic Evaluation of Wp and Wp-M in Soybean

In soybean (Glycine max (L.) Merr.) the W1, W3, W4, Wm, and Wp loci act epistatically to modify floral pigmentation. The wp allele was speculated to influence both anthocyanin production, and protein biosyntheses. Chimeric (purple and pink sectored) flowers were hypothesized to result from the genetic action of a wp-m transposable element. The objectives of this research were to (1) clone a 3'5' flavonoid hydroxylase enzyme from the soybean genome and characterize its cosegregation with flower color alleles, (2) construct a molecular marker linkage map for wp , (3) develop a theoretical model to explain the genetics of the wp-m transposable element, (4) determine the inheritance of wp-m when crossed to pink and purple flowered revertant lines, and (5) report the effect of wp upon agronomic traits in stable flowered lines derived from wp-m. The cloned 3'5 ' flavonoid hydroxylase enzyme fragments from soybean did not show restriction fragment length polymorphism (RFLP) between flower color or pubescence isolines. A molecular marker linkage group for wp was constructed using two RFLP and thirteen simple sequence repeat (SSR) molecular markers. The genetic model for wp-m hypothesized that the pink flower phenotype is the result of insertion of a defective wp-m element into Wp. Purple flowered revertants are proposed to occur due to the excision wp- m, restoring Wp. The chimeric flower phenotype is thought to arise due to random excision of wp-m during development of the somatic tissues. Unusual segregation ratios were observed when wp-m was crossed to pink and purple flowered revertant lines, providing additional evidence that wp-m is a transposable element. Stable pink and purple flowered revertant lines derived from LN89-5320-8 (wp- m) had an unusual amount of variability for several agronomic characteristics. Pink flowered revertant lines were later in maturity, 4 g/kg higher in seed protein content, and 3 g/kg lower in oil content compared to purple flowered revertant lines. The wp allele was speculated to be pleiotropic to quantitative trait loci (QTL) responsible for plant morphology. The influence of anthocyanin, protein biosynthesis, and morphological traits by wp and wp-m is a unique occurrence that has not been reported in other plant species.

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

• Hegstad, Jeffrey Marshall

Contributors dc:contributor

• Nickell, Cecil D.

• Biology, Plant Physiology

Language dc:language

eng

Identifier

(MiAaPQ)AAI9944878

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/87682