Seasonal Changes in the Effects of Auxin on Rooting in Stem Cuttings of Ficus infectoria

Ficus infectoria stem cuttings were treated with 10 and 100 μg/ml each of IAA, IBA, 2,4, -D and NAA at monthly intervals and planted to study their rooting response after recording morphophysiological status and cambial activty of the parent branches. Attempts were also made to surgically expose the cambium before auxin treatment to determine the relationship of seasonal variation in auxin effectivity to cambial activity. The results show that: (1) there are two distinct phases in the sensitivity of Ficus infectoria stem cuttings to auxin-induced rooting; (2) the high rooting phase coincides with renovation of growth and high cambial activity starting in March and lasting through August and the low rooting phase coincides with winter dormancy and low cambial activity; (3) roots emerge in longitudinal rows in slitted auxin-treated cuttings; (4) slitted auxin-treated cuttings root profusely in June when cambial activity is high but not in October when cambial activity is low suggesting a close correspondence of seasonal variation between the rooting activity of auxin and cambial activity.