Date of Award

Fall 2006

Project Type


Program or Major

Plant Biology

Degree Name

Master of Science

First Advisor

Rosanna Freyre


One of the main goals for plant breeders in the floriculture industry is to develop plants with new attributes. Characteristics such as flower size, growth habit, resistance to pests and diseases, flower size, and particularly flower color are among the most important traits to breed and improve. One of the best ways to make a plant popular in the market is to offer a wide variety of flower colors. A. monelli is an ornamental plant used for hanging baskets and as a bedding plant, and until recently, cultivars available were only blue- or orange-flowered. Recent breeding research on this species at the University of New Hampshire developed plants with a new red flower color. Through biochemical analyses it was found that only three anthocyanidins (pelargonidin, delphinidin and malvidin) were responsible for the three flower colors. A model for the anthocyanin pathway for flower color was proposed for A. monelli, which differs from pathways in species such as Petunia and snapdragon in that cyaniding is not synthesized (Freyre & Griesbach, 2004).

The objective of our research was to increase our knowledge about flower color determination in A. monelli. The three main objectives of this study were: (1) to identify anatomical and biochemical differences between upper and lower petal surfaces that contribute to differences in perceived flower color in this species; (2) to test the proposed model for anthocyanin synthesis in several diploid populations segregating for flower color; (3) to isolate and clone one of the genes involved in the anthocyanin pathway in A. monelli. (Abstract shortened by UMI.).