Submitted to: Annual International Plant & Animal Genome Conference
Publication Type: Abstract only
Publication Acceptance Date: 5/1/2006
Publication Date: 5/1/2006
Citation: Cregan, P.B., Hyten, D.L., Zhu, Y., Song, Q., Choi, I., Nelson, R.L., Costa, J., Specht, J.E., Shoemaker, R.C. 2006. Domestication, founding effects and artificial selection - genetic bottlenecks and soybean genetic variability [abstract]. Annual International Plant & Animal Genome Conference. January 13-17, 2006, San Diego, CA. W148. Interpretive Summary:
Technical Abstract: Genetic vulnerability is the condition of being broadly susceptible to attack by pests and is assumed to be proportional to genetic uniformity. Genetic variability of North American soybean at the DNA sequence level was assessed in fragments from 102 genes in each of 26 accessions of G. soja, 52 Asian Landraces, 17 Ancestors of North American cultivars and 25 “Elite Cultivars”. Aligned sequence included 22 kb of coding sequence, 11 kb of UTR, 18 kb of introns, and 2 kb of genomic sequence totaling 53 kb. These data indicated that the low diversity amongst the Elite Cultivars arose not only from diversity loss during domestication of its progenitor G. soja, but also because G. soja itself has low diversity. Indeed, the diversity in G. soja when expressed as nucleotide diversity (' =0.00235) is lower than in other crop progenitors. Domestication further reduced diversity. The Landraces (' =0.00115) retained only 49% of the variability present in G. soja. Thus, the low diversity of North American soybean is not due to the introduction of a few individuals followed by further elimination of variability via selection. The 17 Ancestors (' =0.00100) retained 87% of the diversity of the Landraces and the Elite Cultivars (' =0.00083) retained 83% of the diversity of the Ancestors. Thus, while genetic variability in North American soybean is low, suggesting genetic vulnerability, this is not a result of recent human intervention but rather the intrinsically low variation in cultivated soybean.