Figure 2. Fresh mass, or increases in fresh mass, of in vitro cultures from petiole segments of Pelargonium x domesticum cv. Madame Layal after primary culture and following subcultures dependent on the concentration of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP) in the medium (data were smoothed using distance weighted least squares; mean initial fresh mass: 9.4 mg).