Olive (Olea europaea L.) is one of the most important crops in the Mediterranean area and known by high genetic variation. A comparative account of the polymorphic expression of two antioxidative enzymes (Peroxidase and Super oxide dismutase), one hydrolyzing enzyme (Esterase) and protein electrophoresis was detected from the leaves of four olive cultivars irrigated with different concentrations of saline water. Gel electrophoresis experiments revealed that in most of the cases there were extra numbers of protein bands expressed with relatively low molecular weight in trees irrigated with saline water (2 and 3 bands in Manzanillo, 2 and 1 bands in Picual and 2 bands in case of Dolce cultivar). In all salinity imposed trees, there were sharp increases in band intensity and the number of isoforms of investigated enzyme. Peroxidase increment in trees irrigated with saline water ranged from 2 to 3 polymorphic. Similarly, SOD was shown one band only in all the studied cultivars irrigated or no irrigated with saline water. Increments of Esterase revealed that only one polymorphic band appeared in Eggizi cultivar when irrigated with high concentration of saline water. Genetic variability among four common olive cultivars grown in Sinai, Egypt was assessed 78 fragments of which 29 were polymorphic. The number of polymorphic bands per primer varied from 1 to 6. Genetic similarities were calculated using the Jaccard similarity coefficient. The resulting similarity matrix was subjected to the UPGMA clustering method for dendrogram construction and cultivar differentiation. Our results indicate that ISSR can be useful for genetic diversity studies, to provide practical information for parental selection and to assist breeding and conservation strategies Also, the present results along with those of other researchers show that ISSRs can be used for cultivar differentiation in Olea europaea L. |