Printed in the Philippines ASIA LIFE SCIENCES 24(2): 809-822, 2015 The Asian International Journal of Life Sciences Received 15 January 2015; Accepted 19 February 2015 ©Rushing Water Publishers Ltd. 2015 Characterization and analysis of date palm (Phoenix dactylifera L.) karyotypes OSMAN ALI HAGELAMIN 1,* and ABDULLAH MOSSA M. ALZAHRANI 1 The karyotypes of Khalas (KH), Sukkary (SK), Sheeshi (SS), Shibeebi (SB) and Sillije (SJ) date palm cultivars were investigated. Data showed no variation in chromosome number, 2n = 36, 34 autosomes in addition to XX in females and XY in males. Mean autosomes length ranged from 3.85-9.93 µm and 3.71-2.73 µm for X and Y chromosomes, respectively. The formula of female date palm karyotype was 8m + 4sm +2st + 4t, and submedian Y chromosome. Relative chromosome length ranged from 3.3- 9.38 µm. SS cultivar showed high asymmetry levels by scoring low values of Syi (45.51), TF (42.8) and high values for A1 (0.53), A (0.41) and AI (0.29). Syi developed an inverse relation with A1 and A while A exhibited a direct correlation with A1. Cultivars SK, SB and SJ score medium values of Syi, A1, AI and A. KH cultivar exhibited high symmetry by scoring highest values of Syi (53.68), TF (51.81) and lowest values of A1 (0.44), A (0.34) and AI (0.18). Higher DI value was obtained in SB cultivar (1.34) followed by SJ (1.15) and low DI scores of 0.99, 0.86 and 0.71 were detected in KH, SS and SK, respectively. Stebbins classiication assorted SS as 3B and the other cultivars as 2B, insuring the evolution and asymmetry of SS compared to the other karyotypes. Scatter diagram of Syi-A1 couple has the advantage of revealing high degree of sensitivity to present karyotype interrelationships, followed by AI-A and CVCL-CVCI couples. Keywords: Date palm, Phoenix dactylifera, karyotype, asymmetrical, chromosome, symmetry 1 Biological Sciences, College of Science, King Faisal University, P.O. Box 5324, Hofuf, 31982, Saudi Arabia Kingdom Fax: +966 13 5899557 * Corresponding author: Mobile: +966 597929850 e- mail: oelamin@kfu.edu.sa