This work was carried out to evaluate the effect of seed lipoxygenases genetic
elimination on the sanitary quality and aldehyde production of the seeds of four soybean varieties,
harvested at different periods. Seeds of CAC-1, Doko-RC, UFV-16 and Cristalina varieties and
their respective lines with absence of the three lipoxygenases, called triple-null, were multiplied in
the field and harvested at the R8 stage and 15, 30 and 45 days later. The seeds were submitted to
the blotter test and to the evaluation of total aldehyde content by the MBTH method. It was
concluded that the most frequent fungi were Fusarium spp., Phomopsis spp. and Cercospora
kikuchii. The frequency of total fungi increased with harvest delaying. The harvest delaying
increased the production of aldehyde in the seeds of Cristalina with and without lipoxygenases, of
CAC-1 with lipoxygenases and of Doko RC without lipoxygenases, while in the seeds of the
remaining genotypes, the aldehyde production was minimum in all harvesting times. The genetic
elimination of lipoxygenases from the seeds did not affect the fungi incidence or the aldehyde
production.