EN
The nuclear replication stages in dry and germinating seeds of two sugar-beet cultivars were determined by flow cytometry. For each cultivar two seed lots of similar, high germination capacity, but different in seedling length vigour index (SLVI; applied as quality marker) were studied. Analyses were performed every 12 hours during 72 hours of germination and early seedling growth at 20oC and 15oC. Before start of germination, in all seed lots, about 90% of cells were arrested in the G1 phase of the cell cycle. The proportion of G1 cells decreased with time of germination, faster in higher quality seed lots than in those of lower quality. The G2/G1 ratio in dry seeds was slightly higher for the seeds of higher SLVI, and it increased during germination in all seed lots. However, the difference between higher and lower quality seeds of the same cultivar did not become more distinct during germination.