Dissertation Research: A Genetic Analysis of Seed Coat Polymorphism Within Arabidopsis thaliana

University Of Texas At Austin, Austin TX

Investigators

Abstract

To understand the genetic and developmental bases of naturally-occurring organismal variation is to understand the raw material of evolution itself. Natural variation in seed coat morphology will be genetically and developmentally dissected in the model plant Arabidopsis thaliana. A thorough description of seed coat development for a reference strain (this is the most commonly-used among many available strains) of Arabidopsis will be completed and will serve as the standard to which the development and underlying genetics of both chemically-induced and naturally-occurring (field-collected) mutants will be compared. Both artificial and natural mutants will be developmentally characterized and genetically mapped. These data, in addition to traditional complementation tests (crossing individuals and analyzing their progeny), will be utilized to identify the number of loci affecting variation in this developmental pathway and the frequency and origins of natural seed coat variation. The seed coat serves as the interface between the plant embryo and its environment and its roles are many and varied. This relatively simple, yet highly differentiated structure provides a unique opportunity to investigate evolutionarily important issues and the potential to identify genes responsible for the development of a commercially important organ responsible for such crops as cotton fiber and mucilage, (e.g., Metamucil).