The development of new soybean strain with ti and cgy1 recessive allele

Abstract

Soybean [Glycine max (L.) Merr.] seed is an important dietary source of protein, oil, carbohydrate, isoflavone and other various nutrients for humans and animals. However, there are anti-nutritional factors in the raw mature soybeans. Kunitz trypsin inhibitor (KTI) protein and stachyose are the main anti-nutritional factors in soybean seed. The α′-subunit of β-conglycinin protein exhibit poor nutritional and food processing properties. The genetic removal of the KTI and α′-subunit proteins will improve the nutritional value of the soybean seed. The objective of this research was to develop a new soybean strain with KTI and α′-subunit protein free (titicgy1cgy1 genotype) and proper agronomic traits. A breeding population was developed from the cross of the Bl-1 and 15G1 parents. A total of 168 F2 seeds from the cross of the BL-1 and 15G1 parents were obtained. The segregation ratios of 9: 3: 3: 1 (104 Ti_Cgy1_: 30 Ti_cgy1cgy1: 21 cgy1cgy1Ti_: 13 titicgy1cgy1) between the Ti and Cgy1 genes in the F2 seeds were observed (χ 2= 5.12, P=0.5-0.10). Two F4 plant strains with proper agronomical traits and titicgy1cgy1 genotype (free of both KTI and α′ -subunit protein) were selected and harvested. 2 strains (S1 and S2) had yellow seed coats and hilum. The plant height of the S1 strain was 65 centimeters. The 100-seed weight was 29.2 g. The plant height of the S2 strain was 66 centimeters and 100-seed weight was 26.2 g. The two strains selected in this research will be used to improve the new cultivar that will be free of the KTI and α′-subunit proteins.