2008 Annual Report
1a.Objectives (from AD-416)
Evaluate the progress that can be achieved in developing soybean germplasm with improved meal value utilizing perfect molecular markers.
1b.Approach (from AD-416)
1. Make crosses and develop initial populations segregating for tractable meal traits. 2. Use molecular markers to select desired genotypes. 3. Backcross selected genotypes and develop segregating populations. 4. Advance material identified with desired genotypes. 5. Evaluate meal trait phenotypes and agronimic characteristics of lines.
Objective: Evaluate the progress that can be achieved in developing soybean germplasm with improved meal value utilizing perfect molecular markers (absolutely specific for the target gene), specifically combining reduced allergen, low indigestible sugars e.g. raffinos saccarides, and low phytate (reduced in phytic acid, a non-desireable nutrient).
Since initial crosses were made last summer, we were able to begin two parallel breeding and genotyping approaches (meal genes and oil genes) using a low phytate Tennessee line (TNlowP, TN05-5109). For the meal traits, low raffinosaccharides (RFO) and low P34 allergen were chosen as traits to be selected with perfect molecular markers. The low phytate trait will be incorporated as part of the parent genome unless perfect markers become available.
Because the two meal traits come from independent sources, crosses were made last summer to make independent hybrids using the TNlowP parent. The two sets of hybrids (low-RFO and low p34) were then crossed in Costa Rica, and the resulting double hybrid seeds were selected for the 25% that were heterozygous for both the RFO and P34 genes. Those selected plants are now growing in the field.
The oil traits (mid-level oleic acid and low-linolenic acid) were available last summer in a single line, so a cross was made between TNlowP and the mid oleic/low lin line. Hybrid plants are now growing in the field.
Both the meal lines and the oil lines theoretically contain half their genes from the 50% TNlowP parent, but we have not yet assessed the status of the low phytate trait in any of the lines.
(NP 302 - Component 2A)