USE OF THE RANDOM AMPLIFIED POLYMORPHIC DNA TECHNIQUE TO CHARACTERIZESOYBEAN (GLYCINE-MAX (L) MERRILL) GENOTYPES

We have started a breeding program to genetically eliminate the lipoxy genase isozymes (LOX) from soybean seeds. These enzymes are believed t o be the main cause of off-flavors in soybean products. LOX are presen t in the seed as three isozymes encoded by three different genes, whic h are inherited in a simple mendelian fashion. Mutants lacking each on e of these isozymes have been identified in the world germplasm. To in troduce these null alleles into the Brazilian variety Cristalina, thre e mutant progenitors were chosen: PI 408.251 (LOX1 minus), PI 86.023 ( LOX2 minus), and Ichigowase (LOX3 minus). The random amplified polymor phic DNA (RAPD) technique was used to characterize these progenitors, as well as lines lacking LOX1 (CR(1)), LOX3 (CR(3)), LOX1 and 3 (CR(1, 3)), and LOX2 and 3 (UFV 91-263, UFV 91-401 and UFV 91-717). The resul ts enabled us to establish the fingerprint of each genotype and the ge netic distances among them.