Interaction of stock plant irradiance and auxin in the propagation of apple rootstocks by cuttings

The purpose of the investigation was to examine the effects of different irradiances (light intensities: 8, 16, 38, 54 W/m²) to stock plants on the subsequent rooting of cuttings taken from these stock plants.If the cuttings were rooted without treatment with auxin (indole butyric acid), there was no difference in rooting attributable to the irradiance pretreatments. Auxin treatment of the cuttings was most effective in increasing root numbers and rooting-percentage in cuttings taken from stock plants grown under 8 W/m².