FIGURE 1.

Exogenous hormone-induced production of green calli from Arabidopsis seedlings. (A) Surface-sterilized seeds were plated on a cytokynin- and auxin-enriched agarized solid medium containing sucrose (MS, 0.8% agar, 3% sucrose, 0.25 μg/ml BAP, 0.5 μg/ml 2,4-D) that had a delaying effect on seedling growth and development. Insert: magnification of a well-developed callus originating from the dedifferentiation and proliferation of hypocotyl cells after 3 weeks of germination. (B,C) Observations at the fluorescence stereomicroscope of green calli (B), displaying red autofluorescence of chlorophyll when excited with blue light (C).