|Mcgrath, J Mitchell - Mitch|
Submitted to: Experiment Station Bulletins
Publication Type: Other
Publication Acceptance Date: 5/9/2001
Publication Date: N/A
Technical Abstract: The efficiency of breeding programs depends on early selection of suitable genotypes. Marker assisted selection can be used in early generations to screen large populations prior to field evaluation of advanced generations. Research was conducted to develop Amplified Fragments Length Polymorphisms (AFLP) markers from an F2 population segregating for sucrose content, root color, and genetic male sterility. Carbohydrate analyses were performed vi HPLC on two parents (a sugar beet and a red beet), the F1 hybrid and 119 F2 plants. In the F2 population sucrose content ranged between 355 and 588 mg per g of root dry-weight and only traces of other carbohydrates, such as glucose, were detected. Transgressive segregation was observed for high sucrose contents, reaching 115% of the sugarbeet parent. Root color segregated in the expected Mendelian proportion. Marker analyses were performed with AFLPs, but the dataset is not yet complete. Continuously distributed sucrose contents of the F2 roots indicated that this trait is quantitative in nature and main dominance effects were absent. Root color is explained by the presence of a single dominant gene for the red phenotype. Interestingly, 17 out of 20 plants that had the highest sucrose content were a red phenotype, suggesting high sucrose and high root color are not negatively associated yield components.