ARS | Publication request: Expression of Genes in Soybean (Glycine max) Roots Associated with Flooding Tolerance

Submitted to: Soybean Biotechnology Meeting
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2009
Publication Date: April 21, 2009
Citation: Alves, J.D., Vantoai, T.T., Valliyodan, B., Goulart, P., Lee, J., Fritschi, F., Aldrich, D., Rahman, M., Shannon, G., Nguyen, H. 2009. Expression of Genes in Soybean (Glycine max) Roots Associated with Flooding Tolerance. Soybean Biotechnology Meeting. p. 12.

Technical Abstract: A recombinant inbred population that segregates for flooding tolerance was developed from a cross of the plant introduction, PI408105A and the breeding line S99-2281. A greenhouse study was conducted to determine the mechanisms of the tolerant PI408105A compared to the flood-sensitive genotype, S99-2281. PI408105A plants developed aerenchyma and adventitious roots more rapidly and were able to resume root growth after three days of flooding in comparison to S99-2281 plants. Roots of PI408105A plants also contained more ATP and showed less membrane damage than roots of S99-2281 plants. To understand the molecular mechanisms underlying the tolerance response, root samples were collected from PI408105A and S99-2281 plants at 1, 3, 7 and 10 days after flooding initiation and from control, non-flooded plants. High-throughput qRT-PCR was conducted with mRNA extracted from these samples using primers of 157 root-related transcription factors (TFs), eighteen known anaerobic genes, and three housekeeping genes. Analysis of variance showed that the difference in expression was highly significant among the TFs, treatment, and flooding duration as well as their interactions. While the difference in expression between the genotypes was not significant, the interactions between genotype x TFs, genotype x treatment, and genotype x flooding duration were significant. Information on TFs which expressed differently between the genotypes under flooding stress and their possible role in the flooding tolerance response of the PI408105A will be discussed. Understanding the molecular mechanisms and functions of these TFs will enhance development of cultivars that have the ability to overcome flooding stress for the benefit of soybean producers, especially in regions where soil drainage is either impractical or impossible.