Improvement of rooting in cuttings of two varieties of Nerium oleander L.

Abstract

Research experiments were performed in the Lath and laboratories of Faculty of Science / University of Babylon, to improve rooting response of White and pink oleander . Eighteen treatments were used depending on the best positive results that have been obtained from previous studies.The percentage of rooted cuttings of white oleander (7.41%) and pink oleander (22.59%) . Results also indicated that absolute difficulty in rooting of white oleander in the absence of supplied IBA ( 0.00%) ,while a limited difficulty rooting in pink oleander (6.76% ) .However the highest percentage of rooting for the two varieties white and pink with combination ( IBA + O-coumaric acid) were 33.33% and 60.00% respectively. The bioassay of white and pink oleander exudates proved that , the exudate of white oleander contain inhibitors by reducing rooting response of mung bean to half ( 8.40 )roots compared to control (15.50) root . Whereas, the mung bean cuttings treatment with pink oleander exudate was developed( 16.80) roots which equal statistically to control .Moreover, to reduce or prevent inhibitors effects that present in cuttings exudate the later has been supplied with IBA within combination with exudate of pink and white oleander. The cuttings of mung bean that treated with (white oleander exudate + IBA) developed almost half the number of roots (37.50) compared to control with auxin alone (71.10) root,whereas with a combination (pink oleander exudate + IBA) developed( 58.50) roots which was somewhat equivalent to ( 82.2%) of the control.