Lipoxygenase activities in developing and germinating soybean seeds with and without lipoxygenase. 1. [Glycine max]

Dry-matter accumulation, extracted protein, lipoxygenase-1 (L-1), and lipoxygenase-2 plus -3 (L-2 plus -3) were investigated in two "normal" genotypes and two genotypes lacking L-1 activity in mature seeds. Dry-matter accumulation patterns during seed development were similar in all four genotypes. Protein extracted during seed development or the first week of germination also showed similar profiles for the four genotypes. Changes in L-2 plus -3 activity per milligram extracted protein and total L-2 plus -3 activity per seed again showed similar profiles for all four genotypes during seed development and germination. L-2 plus -3 activity was maximal between days 5 and 20 before physiological maturity and again maximal between days 4 and 7 of germination. The two soybean genotypes that did not have L-1 activity in mature seeds also lacked detectable L-1 activity throughout seed development and the first week of germination. The two normal soybean genotypes displayed similar profiles of L-1 activity. L-1 activity per milligram extracted protein was maximal just before maturity; however, total L-1 activity per seed increased to maturity and then decreased as germination proceeded. The lack of L-1 activity had no obvious effect on the metabolism of the seeds.