Plastid Form Research Articles

The biology of plant mitochondria.

existence of mitochondria in plant cells was first described by Meves (1904) who observed them in the pollen nurse cells of the Nymphaeceae. The presence of mitochondria in plant cells was subsequently confirmed by a number of investigators. The life history of mitochondria remained obscure however because of the cytologists’ inability to distinguish between these bodies and the cytoplasmic particles of similar size which are destined to develop into the various types of plastids characteristic of the plant cell. Sorokin first (1938, 1941) achieved such a differentiation when she found that it is possible to differentiate mitochondria from morphologically similar forms of plastids by vital staining of the mitochondria with the dye Janus green B.

CHLOROPHYLL DEFICIENCIES IN <i>ORYZA SATIVA</i> INDUCED BY X-RAYS

Oryza sativa subjected to X-ray treatment resulted in chlorophyll deficiencies to the extent of about 14 times more than in the series untreated. The occurrence of cream and chlorina seedlings is more frequent than those of white, xanthic, and others.Chlorophyll deficiencies that have been reported previously in this plant are reviewed and classified into genic and plastid mutations, the latter including sporadic and mutable cases. There are two forms of auto-mutable plastids, the one changing from inconstant green to constant white and green, and the other to constant white, but not to constant green.

Handbuch der Pflanzenanatomie

THE volume under notice is one of a series on plant anatomy and cytology. Plastids are probably the most characteristic bodies in plant, as contrasted with animal, cells. As a compilation of nearly all that is known concerning the structure and physiology of plastids, this work will fill a useful place. The extent of the literature bearing on the subject may be judged from the literature list of more than 700 titles. The great range of plastid form and structure is considered for the different groups of plants, including leucoplasts and elaioplasts as well as the various forms of chromato-phores. Under the heading “Constituents of Plastids” the chemical composition of chlorophyll and other pigments, such as fucoxanthin and the carotinoids, is briefly considered. The physiology of chloroplast movement and of greening are discussed, as well as such subjects as “complementary chromatic adaptation.” Carbon assimilation, which has its seat in the chloroplasts, is considered at length as a process, and also in relation to the internal physiology and the external environment (light, temperature, and carbon dioxide content) of the plant. Handbuch der Pflanzenanatomie. Herausgegeben von Prof. K. Linsbauer. Allgemeiner Teil: Cytologie. Band 1: Die Plastiden. Von Dr. Paul N. Schürhoff. Pp. iv + 224. (Berlin: Gebrüder Borntraeger, 1924.) 14s. 9d.