title: Marker assisted accelerated introgression of null allele of kunitz trypsin inhibitor in soybean.
abstract: Development of kunitz trypsin inhibitor (KTI)-free soybean is crucial for soy-food industry as the heat inactivation employed to inactivate the anti-nutritional factor in regular soybean incurs extra cost and affects protein solubility. In the presented work, a null allele of KTI from PI542044 was introgressed into cultivar 'JS97-52' (recurrent parent) through marker assisted backcrossing. Foreground selection in BC1F2, BC2F2 and BC3F2 was carried out using the null allele-specific marker in tandem with SSR marker Satt228, tightly linked with a trypsin inhibitor Ti locus. Background selection in null allele-carrying plants through 106 polymorphic SSR markers across the genome led to the identification of 9 KTI-free lines exhibiting 98.6% average recurrent parent genome content (RPGC) after three backcrosses, which otherwise had required 5-6 backcrosses through conventional method. Introgressed lines (ILs) were free from KTI and yielded at par with recurrent parent. Reduction of 68.8-83.5% in trypsin inhibitor content (TIC) in ILs compared to the recurrent parent ('JS97-52') was attributed to the elimination of KTI.
authors.affiliation: ICAR-Directorate of Soybean Research , Khandwa Road, Madhya Pradesh , India , 452001.
authors.forename: Vineet
authors.initials: V
authors.lastname: Kumar
authors.affiliation: ICAR-Directorate of Soybean Research , Khandwa Road, Madhya Pradesh , India , 452001.
authors.forename: Anita
authors.initials: A
authors.lastname: Rani
authors.affiliation: ICAR-Directorate of Soybean Research , Khandwa Road, Madhya Pradesh , India , 452001.
authors.forename: Reena
authors.initials: R
authors.lastname: Rawal
authors.affiliation: ICAR-Directorate of Soybean Research , Khandwa Road, Madhya Pradesh , India , 452001.
authors.forename: Vaishali
authors.initials: V
authors.lastname: Mourya
keywords: introgression; kunitz trypsin inhibitor; simple sequence repeat marker; soybean