Effect of Light of Several Spectral Bands on the Metabolism of Radioactive IAA in Bean Seedlings.

In a study oln the effect of light quality on plant growth we found a direct relationship between IAA content and plant height (1). Of the several spectral regions used the red produced plants which were the shortest andl had the least IAA. Using low intensity radiation MIeijer (3) also obtained inhibition of elongation in red light but was able to obtain some reversal by the addition of IAA and related compounds. Although we did not obtain reversal, a marked difference in the metabolism of exogenously applied IAA in plants exposed to blue and red light was observed. Therefore, this study to compare the metabolism of labeled IAA by plants grown in (lifferent regions of the spectrum was undertaken.