The effect of 2,4-D and kinetin on dedifferentiation of petiole cells in Arabidopsis thaliana

Phytohormones are indispensable factors regulating plant cell dedifferentiation. In this paper, different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin (KIN) were incorporated in the culture medium and the anatomy of dedifferentiated cells prior to callus formation from Arabidopsis thaliana petiole explants was examined. The results indicated that the cytoplasm of parenchyma cells in the vascular bundle gradually became denser with time of culture only if 2,4-D was included in the medium. The WUSCHEL (WUS) gene was expressed in derivative cells of the vascular bundle after culture for 24 h in the presence of 2,4-D and there was no obvious signal in these cells of cultured petioles with KIN alone. These results suggest that 2,4-D plays an important role in the process of dedifferentiation of vascular bundle cells in Arabidopsis petioles and KIN has no obvious effect on it.