Bulb Histogenesis in Hordeum bulbosum L.

The histological and associated histochemical phenomena occurringin the developing bud of Hordeum bulbosum were investigated.Naturally the bulb is formed by swelling of the lowest internodeof the spike-bearing stern. Bulb initiation began by a rapidcell division followed by cell elongation. The bulb form wasachieved by forming cell files directed diagonally outward inthe upper part and by a periphery meristern contributing cellsto the middle and the lower parts of the bulb internode. Starchaccumulated in the cells before bulb initiation and was utilizedcompletely only in the elongating cells when bulb elongationoccurred. High content of nucleic acids and total protein, demonstratedby specific stainings, was observed in the cytoplasm of cellsof the intercalary meristem at each internode. In the bulb,these stainings became progressively less as the bulb elongated.