Inheritance of dlm and ti genes in Soybean

Abstract

dlm mutant newly identified displays necrotic spots with chlorotic halo despite the absence of any detectable pathogens in soybean. Kunitz trypsin inhibitor (KTI) protein of mature soybean seed is a main anti-nutritional factor and is controlled by Ti allele in soybean seed. The objective of this research was to determine the linkage or independent assortment between dlm allele and ti allele. F2 population was made by crossing between Gaechuck2ho (DlmDlmtiti) and T363 (dlmdlmTiTi) parents. The normal leaf or disease lesion mimic leaf trait of parents and F2 individual plants was recorded at R2 and R3 growth stage from field. The random seeds from individual F2 plants harvested were analysed electrophoretically to determine the presence of the KTI protein. The disease lesion mimic trait was matched to 3 : 1 ratio at the 0.01 levels of probability. The absence of the KTI protein was controlled by a single recessive gene. In F2 generation, the ratios of 102 Ti_Dlm_: 21 Ti_dlmdlm : 24 titiDlm_ : 4 titidlmdlm were observed. Segregation ratio gave a good fit to the 9 : 3 : 3 : 1 ratio based on F2 generation at the 0.01 levels of probability. The data confirmed that dlm allele controlling disease lesion mimic trait was inherited independently with the ti allele controlling absence of KTI protein in soybean.