Germplasm Detection for titi Genotype Using SSR Marker in Soybean

Soybean Kunitz trypsin inhibitor(SKTI) protein is a small, monomeric and non-glycosylated protein containing 181 amino acid residues and is responsible for the inferior nutritional quality of unheated or incompletely heated soybean meal. The objective of this research is to confirm SSR marker(Satt228) tightly linked to the Ti locus using several germplasm accessions with TiTi or titi genotypes for MAS in soybean breeding programs. TiTi genotypes('Jinpumkong2', 'Clark', and 'William') had allele1 and titi genotypes(PI196168, C242, W60, and PI157440) had allele2 in Satt228 marker analysis. 'Jinpumkong2', 'Clark', and 'William'(TiTi genotype) had a Kunitz trypsin inhibitor protein of 21.5 kDa size, and PI196168, C242, W60, and PI157440(titi genotype) did not have the band in protein gel electrophoresis from the mature seed. Cosegregation between the SKTI protein(21.5 kDa size) and allele of Satt228 marker was observed in seven germplasm accessions with different genetic backgrounds. Any recombination between the SKTI protein and allele of the Satt228 marker was not observed. This result indicates that Satt228 marker may effectively utilized to select the plants with the titi genotype.