Genetic Analysis of a Null‐Allele for Lipoxygenase‐3 in Soybean Seeds¹

Abstract

This study describes a major gene which controls lipoxygenase‐3 (L‐3) activity in soybean [ Glycine max (L.) Merr.]. Cultlvars ‘Wasenatsu’ (PI 417 458) and ‘Ichigowase’ (PI 205 085) were found to L‐3 by both immunological and electrophoretic methods. The inheritance of this trait was determined from progeny of crosses between Wasenatsu and either ‘Century’ or ‘Raiden’, two cultlvars that contain high levels of L‐3. Segregation ratios in F 2 and F 3 seeds from selfed plants indicated that absence of L‐3 was due to a single allele that was recessive to the one controlling the presence of the enzyme. Comparable results have been obtained using progeny from the cross Ichigowase ✕ PI 408 251. The latter parent contains L‐3 but lacks L‐1. We propose that the dominant allele be called Lx 3 , whereas the recessive one be designated lx 3 .