Induction of root formation in cuttings by the application of plant hormones

Abstract

The results of an investigation of the effect of IAA, IBA, and NAA and some other growth regulators, food factors, and vitamins alone and in combination with hormone solutions, on root formation of certain stem cuttings, were presented, in order to study their rooting responses. Among the three root forming substances, IBA proved superiority over other two hormones in inducing root induction. Next in order, came NAA and the last IAA. Rooting response of different plant cuttings were found to vary widely. The efficiency of different hormones in rooting response, was found to be different in different plant cuttings and the same cutting showed differences in its response to different concentrations of the same substances. It was also found that mixtures of auxins were more beneficial to root production, in comparison to the hormone when applied singly. Though IAA was found less effective in rooting response, it was observed that IAA in combination with IBA showed excellent stimulation in most of the cuttings. Presence of leaf in cuttings proved beneficial in root forma-tion. The rooting capacity on leafy cuttings was found more respon-sive in production of greater number of roots than leafless cuttings. It was also found that delicate stems, as well as more mature cuttings rooted less. Again, the age effect, also varied widely according to the types of cuttings taken and the different categories of hormones used at different concentrations. Rooting response was also found to vary widely during different seasons. This rooting response was generally found to be high during the months between May - August, in comparison with that in between November - February, every year. Again, the best rooting period also showed wide differences from plant to plant. Certain cuttings rooted more during May - June, while some others exhibited more rootings during August - September. Light was found to play a major role in root formation. Direct sunlight showed some inhibition in the rate of rooting, while greater number of root...