IN VITRO PROPAGATION OF THREE ALMOND CULTIVARS AND THE ALMOND – PEACH HYBRID ROOT-STOCK“HANSEN”

Stem node explants of three almond (Prunus dulcis Mill) cultivars (Om – Elfahm, M-Dalt and Ne Plus Ultra) and the hybrid rootstock “Hansen” cv. were suc-cessfully established and proliferated on Murashige and Skoog medium (MS) sup-plemented with benzyl adenine (BA) at 0.0 - 2.0 mgl -1 and indol butyric acid (IBA) at 0.0 - 0.1 mgl-1 .The highest bud development percentage of stem node explant was obtained with medium contained BA at 2 mgl-1 with or without IBA at 0.1 mgl-1 for M – Dalet and Ne Plus Ultra almond cultivars compared with other treatments. The longest shoot during establishment stage was recorded by “Hansen” rootstock cultured in MS with BA at 2.0 mgl-1 plus IBA at 0.01 mgl-1.Using BA at 1.0 mgl-1 plus IBA at 0.1 mgl-1 and BA at 2.0 mgl -1 plus 0.05 or 0.1 mgl -1gave the highest number of proliferated shoots for Om – Elfahm, M-Dalt and Ne Puls Ultra cvs. and “Hansen”, respectively in the 3rd subculture. The best average proliferated shoot length was achieved with medium supplemented with BA at 1.0 mgl-1 plus IBA at 0.05 mgl-1 or 0.1 mgl-1 for M-Dalt, Ne Puls Ultra and “Hansen” respectively, where-as, using BA at 2.0 mgl -1 plus IBA at 0.1 mgl -1 recorded the longest average prolif-erated shoot for Om- Elfahm cultivar. Microshoots were rooted in modified Bourgin and Nitsch medium supplemented with IBA or NAA at 1.0 mgl-1 only or combination (0.2 IBA mgl-1 + NAA 0.4 mgl-1, IBA 0.4 mgl-1 + NAA 0.8 mgl-1 and IBA 0.5 mgl-1 + NAA 1.0 mgl-1). The large callus (more than 10 mm diameter) was recorded with “Hansen” rootstock and Om – Elfahm treated by IBA at 0.4 mgl -1 plus NAA at 0.8 mgl -1. The greatest rooting percentage (66.67%) was obtained with medium contained IBA at 0.2 or 0.4 mgl-1 plus NAA at 0.4 or 0.8 mgl-1 for “Hansen” rootstock and Ne Plus Ultra shoots.