When the seed germinates in well-drained and well-aerated soil, the coleorhiza, a covering enclosing the radicle or primary root, protrudes first.
Fig. 1 - The coleorhiza protrudes first.
Shortly after the coleorhiza appears, the radicle or primary root breaks through the covering.
Two or more sparsely branched seminal roots follow. These roots eventually die and are replaced by many secondary adventitious roots.
Fig. 3 - Seminal roots
If the seed germinates in water, the coleoptile, a covering enclosing the young shoot, emerges ahead of the coleorhiza. The coleoptile emerges as a tapered cylinder.