GENETIC POLYMORPHISM IN THREE POPULATIONS OF THE GREY-LEAVED CORDIA (CORDIA SINENSIS LAM.) FROM KHARGA OASIS, SOUTHWEST EGYPT

The present study aimed at determining the level of genetic polymorphism within and among three grey-leaved cordia (Cordia sinensis) populations in southwest Egypt.It also aimed at giving a preliminary genetic relationship between populations widely distributed across the different localities in the study area.Twenty-four genotypes representing three populations (Kharga, Dabadib, and Paris areas) were collected from Kharga Oasis to evaluate their genetic variability using 15 random amplified polymorphic-DNA (RAPD) primers.Twelve genotypes from Kharga area were moderately polymorphic (66.4%), while the desert habitats of north and south of Kharga area (Dabadib and Paris oasis), showed lower polymorphism (44.3 and 49.5% respectively).Jaccard's similarity index indicated that Dabadib and Paris populations were related to each other with the highest similarity index (0.69).The dendrogram generated by the agglomerative clustering technique produced three main clusters: two of them for Kharga genotypes and the 3 rd for Dabadib and Paris genotypes indicating the close relations between these populations.The genetic diversity indicated that Paris populations had the highest Shannon and Simpson indices (5.3 and 242.4,respectively), while Kharga had the lowest (4.8 and 198.4).The higher polymorphism in Kharga area than in Dabadib and Paris may suggest the species confinements into more favorable and very stable habitats.The current findings may help in the conservation of such medicinally and economically important species for future use by local people in such harsh and remote habitats.However, the study showed the need for in-and ex-situ conservation of C. sinensis for plant breeding programs and the future use in medicine, fodder and wood industry.The polymorphic primers identified here will be useful in identifying evolutionary relationship and taxonomic position to understand the phylogeny of the genus Cordia belonging to family Boraginaceae.