RESUMO
We have started a breeding program to genetically eliminate the lipoxygenase isozymes (LOX) from soybean seeds. These enzymes are believed to be the main cause of off-flavors in soybean products. LOX are present in the seed as three isozymes encoded by three different genes, which are inherited in a simple mendelian fashion. Mutants lacking each one of these isozymes have been identified in the world germplasm. To introduce these null alleles into the Brazilian variety Cristalina, three mutant progenitors were chosen: PI 408.251 (LOX1 minus), PI 86.023 (LOX2 minus), and Ichigowase (LOX3 minus). The random amplified polymorphic DNA (RAPD) technique was used to charactetize these progenitors, as well as lines lacking LOX1 (CR1), LOX3 (CR3), LOX1 and 3 (CR1,3), and LOX2 and 3 (UFV 91-263, UFV 91-401 and UFV 91-717). The results enabled us to establish the fingerprint of each genotype and the genetic distances among them.