The Effect of Growth-regulating Substances and Light on Olive Callus Growth in vitro

In vitro olive callus cultures were established; auxin was notobligatory for the early development of the callus. However,after a number of subcultures, both an auxin and a cytokininwere needed for growth. IAA was the most efficient auxin ininducing growth, although 2,4-D was also very active. Very shortperiods of red-light illumination were sufficient to effectgreening of the tissue. A particularly high ratio of chlorophyllb/a was found under all light conditions tested. All light treatmentsstimulating chlorophyll synthesis caused a reduction in growthafter four subcultures.