Journal Article

Artificial selection for determinate growth habit in soybean

Li, Yinghui, Qiu, Lijuan, Ma, Jianxin, Specht, James E, McClean, Phillip E, Lee, Rian, Wang, Xiaobo, Nelson, Randall L, Tian, Zhixi

2010

Overview

Determinacy is an agronomically important trait associated with the domestication in soybean (Glycine max). Most soybean cultivars are classifiable into indeterminate and determinate growth habit, whereas Glycine soja, the wild progenitor of soybean, is indeterminate. Indeterminate (Dt1/Dt1) and determinate (dt1/dt1) genotypes, when mated, produce progeny that segregate in a monogenic pattern. Here, we show evidence that Dt1 is a homolog (designated as GmTfl1) of Arabidopsis terminal flower 1 (TFL1), a regulatory gene encoding a signaling protein of shoot meristems. The transition from indeterminate to determinate phenotypes in soybean is associated with independent human selections of four distinct single-nucleotide substitutions in the GmTfl1 gene, each of which led to a single amino acid change. Genetic diversity of a minicore collection of Chinese soybean landraces assessed by simple sequence repeat (SSR) markers and allelic variation at the GmTfl1 locus suggest that human selection for determinacy took place at early stages of landrace radiation. The GmTfl1 allele introduced into a determinate-type (tfl1/tfl1) Arabidopsis mutants fully restored the wild-type (TFL1/TFL1) phenotype, but the Gmtfl1 allele in tfl1/tfl1 mutants did not result in apparent phenotypic change. These observations indicate that GmTfl1 complements the functions of TFL1 in ARABIDOPSIS: However, the GmTfl1 homeolog, despite its more recent divergence from GmTfl1 than from Arabidopsis TFL1, appears to be sub- or neo-functionalized, as revealed by the differential expression of the two genes at multiple plant developmental stages and by allelic analysis at both loci.

• Publisher: National Academy of Sciences,National Acad Sciences
• Subject: Alleles / amino acid substitution / Amino acids / Arabidopsis - genetics / Arabidopsis Proteins - genetics / Arabidopsis thaliana / artificial selection / Base Sequence / Biological Sciences / China / Crop science / Crops, Agricultural - genetics / Crops, Agricultural - growth & development / Cultivars / Determinacy / determinate growth / Developmental stages / Domestication / Evolution, Molecular / Gene expression / Gene Expression Profiling / Gene Expression Regulation, Plant / gene transfer / genes / Genes, Plant - genetics / Genetic Complementation Test / Genetic diversity / Genetic loci / Genetic Markers / Genetic mutation / Genetic Variation / Genotype & phenotype / Genotypes / Glycine max / Glycine max - genetics / Glycine max - growth & development / Glycine soja / GmTfl1 gene / Growth habit / Molecular Sequence Data / mutants / Mutation - genetics / Phenotypes / plant breeding / Plant growth / Plants / point mutation / Polymerase chain reaction / Proteins / regulator genes / Selection, Genetic / Sequence Homology, Nucleic Acid / Soybeans / Time Factors / transgenic plants / wild relatives