Natural variation in the genes responsible for maturity loci E1, E2, E3 and E4 in soybean

Area of Science:

• Plant genetics
• Molecular biology
• Agricultural science

Background:

• Flowering time is crucial for soybean (Glycine max) seed production.
• Genes E1, E2, E3, and E4 control soybean flowering, but natural variations require further study.

Purpose of the Study:

• Identify novel alleles for soybean flowering loci.
• Develop diagnostic tools for these alleles.
• Analyze allele combinations for plant adaptability.
• Assess the cumulative impact of E1-E4 loci on flowering time.

Main Methods:

• Sequenced genes and flanking regions of 39 soybean accessions using primer walking.
• Employed DNA markers for systematic allele discrimination.
• Determined genotypes at E1-E4 loci for 63 accessions.
• Recorded flowering times across three sowing dates.

Main Results:

• Discovered a new E1 allele (e1-re) with a LINE insertion in the promoter.
• Observed insertion/deletion of 36 bases in the E2 locus intron (E2-in, E2-dl).
• Established PCR-based markers for E1-E3 allele discrimination.
• Linked E1-E4 allelic combinations to ecological types, explaining 62-66% of flowering time variation.

Conclusions:

• Advanced understanding of E1-E4 loci in soybean flowering and geographic adaptation.
• Indicated the potential involvement of additional, yet unidentified, genes in soybean flowering control.