**2.1 Plant genotypes**

Soybean genotype C242 (clark derived near isogenic line) has the *ti* allele and lacks a soybean kunitz trypsin inhibitor. C242 was a generous gift from J. Specht, professor of Agronomy, University of Nebraska-Lincoln, USA. Cultivar Jinpumkong2 and Clark has kunitz trypsin inhibitor protein band (*TiTi*). Two mapping populations were developed. Population 1 was derived from a cross between cultivar Jinpumkong2 and C242. Population 2 was made from a mating between cultivar Clark and C242. The F1 plants from two populations were grown in the greenhouse to produce F2 seeds.
