Soybean [Glycine max (L.) Merr.] protein is excellent nutritional factors and is widely used for human and animal feed in the world. Glycinin(11S globulin) and ß-conglycinin(7S globulin) account for storage protein from 70% to 80% in soybean seed. ß-conglycinin is composed of α’, α and ß subunits, encoded by the genes Cgy1, Cgy2, and Cgy3, respectively. β-conglycinin protein exhibits poor nutritional and food processing properties. Lipoxygenase is responsible for the beany flavor and is responsible for the inferior nutritional quality of unheated or incompletely heated soybean meal. The objective of this research was to select F2 seeds with lipoxygenase-free and low content of ß-conglycinin for breeding of high quality soybean cultivar. A total of 582 F2 seeds were obtained from the cross of 10F1(lipoxygenase-free, normal content of 7S protein) and T311(lipoxygenase-present, low content of 7S protein). Lipoxygenase and 7S proteins in mature seeds were detected by SDS-PAGE. The segregation ratio of 3 : 1 for Shr locus (418 Shr_ : 164 shrshr) were observed. This result shows that the Shr locus is controlled by a single gene. Among 164 shriveled seeds, 6 F2 seeds with lipoxygenase-free, α’ subunit-free, and low content of α and ß subunit were selected. Among 418 normal seeds, 6 F2 seeds with lipoxygenase-free, α’ subunit-free, and low content of α and ß subunit were selected. These results will be used in breeding program for improving high quality soybean cultivar.

Soybean [Glycine max (L.) Merr.] proteins are widely used for human and animal feed in the world. Glycinin (11S globulin) and β-conglycinin (7S globulin) account for storage protein from 70% to 80% in soybean seed. 7S globulin protein exhibits poorer nutritional and food processing properties. β-conglycinin is composed of α’, α, and β-subunits. α′-subunit of 7S globulin are main antinutritional factors in soybean seed. The absence of α′-subunit were controlled by single recessive alleles, cgy1. Leaf chlorophyll-deficient mutants controlled by y9 locus have been observed frequently and are useful in genetic studies in soybean. So far, 19 single recessive gene yellow leaf mutants and one duplicate recessive gene mutant have been described. The y9 type found in T135 is yellow at emergence, becoming greenish-yellow by maturity. The objective of this research was to confirm the linkage or independent assortment between cgy1 gene and y9 gene. The F1 seeds from C-142 (α′-subunit of 7S globulin present, leaf chlorophyll -deficient: Cgy1Cgy1y9y9 genotype) x PI line (α′-subunit of 7S globulin absent, normal leaf type: cgy1cgy1Y9Y9 genotype) were obtained. F1 seeds obtained were planted in a greenhouse and F1 hybridity was checked on morphological traits. All F2 seeds were planted at field in May 2012. Leaf chlorophyll-deficient trait of F2 individual plants will be recorded at growth stage from field. Presence and absence of α′-subunit of 7S globulin protein will be checked by SDS-PAGE based on each F₂single plant. Chi-square analysis was used to test the goodness-of-fit of observed ratios with expected ratios for independent assortment or linkage.

Leaf chlorophyll-deficient mutants controlled by y9 locus have been observed frequently and are useful in genetic studies in soybean. So far, 19 single recessive gene yellow leaf mutants and one duplicate recessive gene mutant have been described. The y9 type found in T135 is yellow at emergence, becoming greenish-yellow by maturity. Soybean Kunitz trypsin inhibitor protein has been proposed as one of the major antinutritional factor. The absence of Kunitz trypsin inhibitor protein in mature seed is inherited as a recessive allele designated ti. The objective of this research was to confirm independent inheritance between ti gene and y9 gene. The F1 seeds from Gaechuck#1 (Kunitz trypsin inhibitor protein absent, normal leaf type) x C-142 (Kunitz trypsin inhibitor protein present, leaf chlorophyll -deficient) were obtained. F1 seeds obtained were planted in a greenhouse and F1 hybridity was checked on morphological traits. All F2 seeds were planted at field in May 2012. Leaf chlorophyll-deficient trait of F2 individual plants will be recorded at growth stage from field. Presence and absence of Kunitz trypsin inhibitor protein will be checked by SDS-PAGE based on each F₂single plant. Chi-square analysis was used to test the goodness-of-fit of observed ratios with expected ratios for independent assortment or linkage.