Submitted to: Integrated Crop Management Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/15/1998
Publication Date: N/A
Citation: Interpretive Summary: Reduced vigor due to iron deficiency is a serious problem in soybean, especially on soils with high pH. Leaf yellowing and subsequent poor plant health due to iron deficiency causes millions of dollars in lost revenue to soybean growers every year. Breeders have bred more iron efficient soybeans for years with some success. A better understanding of the genetics controlling this trait would help us to develop more efficient beans. In this study the authors discovered that one gene can make a very large contribution to the trait, but that the gene has different effects in different cultivars. They also 'tagged' the gene with markers that can help breeders select better cultivars. This work is a breakthrough in understanding the genetic control of this complex physiological trait and will help breeders in designing strategies for developing iron efficient soybeans.
Technical Abstract: Iron deficiency chlorosis (IDC) of soybean occurs on calcareous soils when a cultivar is unable to utilize the available iron (Fe). In this study 90 RFLP and 10 SSR markers in the Pride B216 x A15 population, and 82 RFLP, 14 SSR and 1 morphological I (hilum color) markers in the Anoka x A7 population were used to map quantitative trait loci (QTL) affecting IDC. In the Pride population, 120 random F2 plants were used, 92 were used in the Anoka population. In the Pride population, QTL with minor effects were detected in five linkage groups indicating a polygene mechanism for IDC. In the Anoka population, two QTL were each mapped for visual scores and chlorophyll concentrations. One of the QTL had a major effect and was mapped in the same interval of linkage group N using both visual scores and chlorophyll concentrations, verifying that one major gene is involved in segregation for IDC in this population. Two QTL on linkage groups I and N were common to the Pride of Anoka populations and were considered for use in marker-assisted selection.