Ultrastructural changes in the embryo, and separately in the endosperm, before and after the radicle protrusion of the silver fir seeds (Abies alba Mill.) were studied. Lipid bodies and protein bodies are the main storage structure in the cells of the seeds after the imbibition for 24 hrs. Rare microbodies were also visible. The cellular organization and degradation of the storage material were more rapid in the embryonic than those in the endosperm cells. After the radicle protrusion, numerous mitochondria, dictyosomes and microbodies were visible in the endosperm cells, indicating high metabolic activity. Chloroplasts with many thylakoids and large starch granules developed in the growing embryo.
Kovač et al. (Sat,) studied this question.