| Title: | Validation of Low-Phytate QTLs and Evaluation of Seedling Emergence of Low-Phytate Soybeans |
| Authors: | Gao, Y., Biyashev, R., Saghai Maroof, M., Glover, N., Tucker, D., Buss, G. |
| Source: | Crop Sci. 2008, 48(4):1355-1364 |
| Abstract: | M153-1-4 is a low-phytate (LP) soybean [Glycine max (L.) Merr.] mutant derived from chemical mutagenesis, possibly from a single gene mutation. However, the inheritance of LP in CX1834, as descended from M153-1-4, has been shown to involve two independent loci which were subsequently mapped to linkage groups (LGs) L and N. The objectives of this study were to (i) validate the two previously identifi ed LP QTLs in CX1834 using 208 F2:5 lines of CX1834-1-6 Å~ V99-3337, (ii) characterize associations of LP QTLs with phytate content in a set of F2:5 and backcross (BC) lines as derived from phenotypic or genotypic selections, and (iii) evaluate the impact of LP on seedling emergence. Overall, the previously reported LP QTLs were validated in this study. However, observations of natural genetic variation and transgressive segregants suggest that additional LP QTLs could exist, potentially contributed by V99-3337, the other parent of the validation population. A perfect correlation was found between phenotypic (phytate-based) and genotypic (marker-based) selections for LP lines in this study. However, fi ndings of LP marker genotypes in the high phytate (HP) phenotypic selections suggest a potential linkage between HP and LP genes on LG L in CX1834. LP lines did not have uniformly low emergence in this study. Under some environments, HP and LP lines had little difference in seedling emergence in the fi eld. |