The phenomenon of fasciation in soybean as a consequence of spontaneous mutation has been known for a long time under the name of 'Keito-marne' or 'Shakujo-rnarne'. Fasciated soybean has a peculiar character in which the stern is flattened, with a few number of branches. The flowers develop as a cluster at the top of the stem and most pods accumulate at that part (Takahashi and Fukuyama, 1919; Takagi, 1929). It has been reported that stem fasciation is controlled by a single recessive gene, f (Takagi, 1929).
Wongyai, W.; Furuya, T.; and Matsumoto, S.
"Research Notes : Japan : Effect of temperature on fasciation characters in fasciated
Soybean Genetics Newsletter: Vol. 11
, Article 19.
Available at: https://lib.dr.iastate.edu/soybeangenetics/vol11/iss1/19