DIFFERENT CELL COMPOSITIONS IN MUNGBEAN (VIGNA-RADIATA (L) WILCZEK) COTYLEDON CALLI

Two types of cell masses namely, green and compact (GC) and white and friable (WF) were initiated from a single, identical callus mass of th e mature cotyledon of mungbean strain IPB 22-117 upon subculture. Cryo -SEM examination of these two types of cell masses revealed distinct c ell compositions. The GC mass was composed mainly of small, round, clo sely-packed cells while the WF mass was of the elongated, loosely-pack ed cells. Occasionally, a few big round cells were found among elongat ed cells. Differential response of the two types of masses in suspensi on culture was also observed. Of the two, the WF mass gave a fine cell suspension in L6 medium (Kumar et al., 1988). Light microscopic obser vations of the WF cell suspension under varying periods of culture sho wed different cell types. When plated, big, round cells generally unde rgo cell division. Colony formation was not profuse among elongated ce lls and most of them remained in their original state.