Mungbean - Rhizomum in Association with Wheat Calli

Aseptically grown embryo calli of Triticum aestivum (L.) were inoculated with Vigna-Rhizobium (Strain 11a, 17bt and Os2). The calli and bacteria were allowed to interact for about ten days at an ambient temperature. Ultrathin sections of such inoculated calli were examined under a Transmission Electron Microscope (TEM). Large number of rhizobial cells were present in intercellular spaces of wheat callus. Metabolic exchanges between the plant and bacterium were inferred from the morphological changes in the latter which were pleiomorphic and presence of acetylene reduction activity. Presence of capsular material around the bacterial cells coould also be seen.i>.