Effects of offshoot sizes and indole-3-butyric acid on rooting of date palm (phoeniz dactylifera L.).

To study the rooting response of date palm offshoots Research Center fro September 2008 to April 2009 to evaluate the effects of various Indole-butyric acid (IBA) concentrations and offshoot sizes on rooting abiligy of dte palm.The experiment comprised of factorial combinations of 3 types of date palm offshoot sizes (10 =+ 2.5, 15=+2.5 and 20 =+ 2.5 cm) and 4 concentrations (0, 1000,2000 and 3000ppm) of the rooting hormone IBA, in a Randomized Complete Block design, with three replications.Generally, most of ht eparameters considered varied significantly due to differences in offshoot size and concentration of IBA compared with the control.The larger the diameter of date palm offshoots and the higher the concentration of IBA, the higher were the number (47.87) (128.87) and length of roots (46.37cm) (35.42cn) with both large and small diameter respectively.Increasing the concentration of IBA up to 2000 ppm had no significance (p0.05) increased when larger (20=+ 2.5cm) sized offshoots were treated with higher concentrations of IBA compared with the control.percentage of rooting ability of offshoots with small (10=+ 2.5 cm) or medium (15 =+ 2.5cm) diameter.While those large sized offshoots highly responded to the IBA treatment.The number of buds developed on larger sized offshoots significently (P0.05) increased in response to 1000,2000 and 3000ppm of IBA.compared with the control.Percentageof rooted offshoots (P0.01),percentage of non-callusing offshoots (P0.05), length of buds (P0.01) and survival percentage (P0.001) were significantly increased when the maximum concertation of IBA was used.Neither increasing the concentration of IBA nor the size of offshoots significantly (P0.05) affected the number of non-rooted but callusing offshoots. Increasing the concentration of IBA from 0 to 3000 ppm significantly (P0.05) increased both fresh (145.63g) (15.62g) and dry weight (55.7g) (4.82g) of roots with large and small diameter respectively.Treating offshoots with 3000 ppm IBA was the most effective treatment in increasing the fresh and dry weight of roots that develop from offshoots with application of IBA to the basal portion of offshoots with 20 No. 2.5 cm diameter to be effective in promoting rooting and subsequent survival of date palm offshoots.Therefore, date palm offshots obtained rom local landraces could be propagated vegetatively by using IBA as a root inducing hormone.However, further investigation might be needed to find the optimum concerntration of IBA and size of date palm offshoots for improving cultivation of date palm in Afambo and its surroundings.