Die Submikroskopische Entwicklung der Chromoplasten in den Blüten von Ranunculus Repens L

Summary

Electron microscopic studies of the development of yellow chromoplasts in the perianth ofRanunculus repens L. show, that the structures characteristic of these yellow plastids are homogeneous osmophilic globuli up to 1500 Å in diameter which first appear in young chloroplasts or leucoplasts. They are formed between the lamellae and, while increasing in size and number, they destroy the lamellar structure until at maturity only these droplets remain lining the inner surface of the plastid membrane. It is most likely that they are formed as a result of lipophanerosis of the lamellar structures and that they represent the final stage in a monotropic plastid metamorphosis and can not revert to chloro-, or leucoplasts. This is supporting evidence for the theory of monotropic plastid transformation.

Transition forms have been found, having structures characteristic of both leuco-, chloro-, and chromoplasts at the same time, thus making the usual classification into these categories no longer tenable on the basis of submicroscopic morphology.