Root Initiation in Aerial Offshoots of Date Palm (Phoenix dactylifera) by Exogenous Application of Auxins

Abstract

Date palm(Phoenix dactylifera)is commercially propagated through offshoots. Alongwith thisrooted offshootthe tree also produces aerial offshoots,which arerootlessand die after plantation. In this study attempts have been made to evaluate the effect of auxins on the root initiation of the aerial offshootsof date palm cv. Hillawi.Therefore, an experiment was conducted to evaluate theeffect of IAA (500 ppm), NAA(500 ppm), alone and in combination on root initiation in aerial offshoots of date palm cv. Hillawi. The auxins were applied to the aerial shoots by injection method. The experiment was laid out according to Randomized Complete Block Design (RCBD) with four treatments(Control, 500pmm IAA, 500ppm NAA and 500ppm IAA+NAA) andeach treatment was replicatedthrice.Injection method was used to apply the hormones and after the applicationof auxinsthe base of each offshoot was wrapped carefully with gunny bags having pinewood shaving as rooting media.After 40 days of supplication,offshootswere detached,and parameters were collected. Dataindicated that NAA @ 500ppm gave highest rooting percentage (24.5%), total number of roots per offshoot (82.33) and total weight of roots per offshoots (607.4g) as compared to other treatments. Similarly, a greaternumber of smaller roots (dia<0.5cm) was also achieved in offshoots treated with 500ppm NAA. Hence, it may be concluded that root initiation was remarkablein NAA alone and in combination with IAA at 500ppm concentration in comparison to other treatments.