EREZ, A., The Volcani Institute of Agricultural Research, Bet Dagan, Israel
KADMAN‐ZAHAVI, A., The Volcani Institute of Agricultural Research, Bet Dagan, Israel

Young peach plants (Prunus persica) were grown outdoors under different colored filters, to examine the effect of light quality on plant behavior. It was found that under blue light growth rate, leaf size and number, rate of spring bud opening and secondary branching were very similar to control plants grown under neutral shade. Blue + far‐red light showed an overall strong inhibitory effect on all these characteristics. Red + far‐red light produced the strongest growth activity with best results in growth rate and leaf size and number. The phytochrome pigment system was suggested to be the only pigment regulating growth under high light intensities. Blue and blue + far‐red light acted antagonistically on apical dominance features of the tree. The former produced a wider tree with nearly horizontal shoots, while the latter produced a more erect narrow tree. Copyright © 1972, Wiley Blackwell. All rights reserved