Abstract: Provided herein are methods for evaluating associations between candidate markers and a trait of interest in a plant population. In various embodiments, the plant population is a breeding population, particularly early stage breeding populations. The methods include obtaining a genotypic value for candidate markers and correlating the marker with the trait. Various association models can be used to evaluate the association, and include statistical methods relevant to the structure of plant breeding populations. Population structure may be accounted for in the association models by using Principle Component Analysis. Further provided is a novel statistical approach for association mapping in early stage breeding materials using a transmission disequilibrium based methodology.