Structural transformation and modulation of succinic dehydrogenase activity in the mitochondria of germinating seeds.

Ultrastructural transformation of mitochondria in the cotyledons of dry and germinating seeds of Vigna sinensis from the 'orthodox' to 'condensed' forms is coupled with an increasing rise in the specific activity of succinic dehydrogenase (SDH). Apparently, the transformation of mitochondria to the 'condensed' form associated with the utilization of substrate which is reflected in the rise in enzyme activity. During the process of germination, the mitochondria of the cotyledonary cells undergo three different phases namely, (1) activation phase, (2) preparatory phase, and (3) multiplication phase.